ELECTROS LAG CASTING OF VALVE BODIES by DEEPAK B.Tech., Indian Institute A THESIS THE of SUBMITTED Technology, IN REQUIREMENTS MASTER OF GUPTA Kanpur, PARTIAL FULFILMENT FOR D E G R E E OF THE APPLIED India, OF SCIENCE in THE FACULTY Department We accept to THE of OF Metallurgical this the GRADUATE thesis required UNIVERSITY OF Deepak Engineering conforming standard BRITISH January (c) as STUDIES COLUMBIA 1982 Gupta, 1982 3E-6 In p r e s e n t i n g t h i s t h e s i s i n p a r t i a l f u l f i l m e n t of requirements f o r an advanced degree a t the the University o f B r i t i s h Columbia, I agree t h a t the L i b r a r y s h a l l make it and f r e e l y a v a i l a b l e for reference study. I further agree t h a t p e r m i s s i o n f o r e x t e n s i v e copying of t h i s t h e s i s f o r s c h o l a r l y purposes may be department o r by h i s or her granted by the head o f representatives. my It is understood t h a t c o p y i n g or p u b l i c a t i o n of t h i s t h e s i s f o r f i n a n c i a l gain s h a l l not be allowed without my permission. Department o f The U n i v e r s i t y of B r i t i s h 2075 Wesbrook P l a c e Vancouver, Canada V6T 1W5 Da (2/79) t e OOW- f8- , t^S2~- Columbia written ii ABSTRACT The used in steel Electroslag the castings. tion of valve the alloy and tested by concluded required valent This that advantages or better method for the steel with and (AISI valve the there present may be code the been widely of high quality results 316 and of and bodies offers of were conventional difficulties qualification shaped at and U.B.C. methods. easily Therefore examina- CF-8M) made distinct properties an simple ACI destructive specifications. the has production production technique than process presents 4340) this ASME/ASTM to work the non-destructive i n g s H o w e v e r , the (AISI (ESC) for Stainless steel production Union ESC p r o c e s s bodies. low is Soviet Casting It quality meet and the they are equi- castings and forc- in reconciling requirements. TABLE OF CONTENTS Abstract Table of Contents L i s t of Tables L i s t of Figures Acknowledgements — • Chapter 1 INTRODUCTION 2 PROCESS DESCRIPTION AND CHARACTERISTICS 2.1 E l e c t r o s l a g R e m e l t i n g P r o c e s s C h a r a c t e r i s t i c s .. Which A f f e c t the P r o p e r t i e s o f the M a t e r i a l s ... 2.1.1 2.1.2 3 Related to Related to Chemical Solidification PRESENT WORK 3.1 3.2 3.3 3.4 4 Characteristics Refining Characteristics structure Furnace Design V a l v e Mold Design Melting Procedure Selection of Slags for ESC P r o c e s s EVALUATION OF ESC VALVE CASTINGS A . S T A I N L E S S STEEL VALVE CASTINGS 4.1 4.2 R e m e l t i n g Log f o r S t a i n l e s s S t e e l N o n - D e s t r u c t i v e T e s t i n g (NDT) 4.2.1 4.2.2 4.2.,3 4.3 Dye P e n e t r a n t T e s t U l t r a s o n i c Test Radiography Test Destructive 4.3.1 4.3.2 4.3.3 Testing (DT) Macrostructures Microstructures D e l t a F e r r i t e Measurements ESC V a l v e s ... 4.3.4 4.3.5 4.3.6 4.3.7 4.4 Interdendritic Microsegregation C o m p o s i t i o n A n a l y s i s and M a c r o s e g r e g a t i o n . . . P r o b l e m s W i t h A l l o y i n g D u r i n g t h e ESC Operation P r o b l e m s W i t h U s i n g C a s t E l e c t r o d e s i n ESC Operation Mechanical Properties 4.4.1 Tensile Testing B . LOW ALLOY STEEL VALVE CASTINGS 4.5 4.6 R e m e l . t i n g L o g f o r A I S I 4340 ESC V a l v e s N o n - D e s t r u c t i v e T e s t i n g (NDT) 4.6.1 4.6.2 4.6.3 4.7 Destructive 4.7.1 4.7.2 4.7.3 4.7.4 4.7.5 4.7.6 4.8 Dye P e n e t r a n t T e s t Ultrasonic Test Radiography Test Testing (DT) Macrostructures Sulphur Prints Interdendritic Microsegregation C o m p o s i t i o n A n a l y s i s and M a c r o s e g r e g a t i o n Heat T r e a t m e n t and M i c r o s t r u c t u r e s Dimensional Measurements Mechanical Properties 4.8.1 Tensile Testing 4.8.2 Impact T e s t i n g 5 OTHER T R I A L S AND FUTURE WORK 6 SUMMARY AND CONCLUSIONS REFERENCES TABLES^ FIGURES APPENDIX 1 - ASME/ASTM S p e c i f i c a t i o n s ... V L I S T OF TABLES Tables Page I Remelting Log f o r S t a i n l e s s II Ferrite Numbers of Stainless III Average Ferrite Numbers o f S t a i n l e s s Determined Steel Steel ESC V a l v e s 83 Castings Steel by Magne-Gage and S c h o e f e r ' s Castings Diagram 85 IV Interdendtitic Microsegregation V Chemical Composition o f V a l v e No. 5 (CF-8M) 87 VI Chemical Composition o f Valve No. 6 (316) 87 VII Chemical Composition o f V a l v e N o . 7 (316+Cr) 88 VIII Chemical Composition o f V a l v e No. 9 (CF-8M) 88 IX Chemical Composition o f V a l v e N o . 10 (316+Cr+Mo) 89 X Chemical Composition of Conventional 89 XI Percent Parent Composition Ratios 84 o f CF-8M C a s t i n g s Casting .. (CF-8M) o f C r a n d Mo i n A r e a s 1 a n d 2 a n d t h e V a l v e C a s t i n g N o . 10 90 XII Tensile XIII T e n s i l e P r o p e r t i e s o f Valve No. 9 , Conventional Casting and ASME/ASTM S t a n d a r d s f o r A I S I 316 a n d A C I C F - 8 M T e n s i l e P r o p e r t i e s o f l a r g e specimens from V a l v e N o s . 6 and 91 9 and s m a l l 92 XIV Properties 86 o f V a l v e N o s . 5 , 6 and 7 specimens XV Remelting XVI Interdendritic from a l a r g e 90 specimen L o g f o r A I S I 4 3 4 0 ESC V a l v e s Microsegregation at the Centre ESC V a l v e s 93 o f AISI 4340 94 XVII Chemical Composition o f V a l v e N o . 3 (4340) 95 XVIII Chemical Composition o f V a l v e No. 8 (4340) 96 XIX Chemical Composition o f V a l v e No. 13 (4340) 97 XX Chemical Composition o f V a l v e N o . 14 (4340.) 9 7 vi Page Tables XXI Sulphur Contents of XXII Dimensional XXIII Tensile XXIV Tensile Properties Bar XXV XXVI XXVII XXVIIIa t h e A I S I 4 3 4 0 E l e c t r o d e a n d ESC V a l v e s . M e a s u r e m e n t s o n V a l v e N o s . 1 1 , 12 a n d 13 Properties of AISI of A I S I 4340 Hot ... 99 Rolled 100 Transverse Tensile Properties M e l t e d A I S I 4340 S t e e l s 7 5 of Air-melted Longitudinal Mechanical Properties R e m e l t e d A I S I 4340 S t e e l 7 5 and Vacuum-arc 100 of B a r S t o c k Made From 100 l M e c h a n i c a l P r o p e r t i e s o f ESR 4340 M a t e r i a l i n t h e T r a n s verse D i r e c t i o n Heat T r e a t e d t o D i f f e r e n t S t r e n g t h Levels^ ... 101 Tensile Properties ( A I S I 4340) 101 of L a r g e S p e c i m e n s f r o m ESC V a l v e X X V I l i b T e n s i l e P r o p e r t i e s o f Small Specimens from Large S p e c i m e n f r o m ESC V a l v e N o . 8 ( A I S I 4 3 4 0 ) XXIX 98 4340 E l e c t r o s l a g C a s t V a l v e s Conventional 98 FATT V a l u e s E s t i m a t e d f r o m Ductile-Brittle-Transition C h a r a c t e r i s t i c s o f t h e ESC and E l e c t r o d e M a t e r i a l :i No.8 101 102 VI 1 L I S T OF FIGURES Figure Page 8 1 E l e c t r o s l a g cast products 2 'YOZO' 3. Schematic of 4 5 F r a c t u r e t o u g h n e s s o f ESC A I S I 4 3 4 0 s t e e l c o n t a i n i n g v a r y i n g amounts o f s u l p h u r ^ E l e c t r o s l a g casting i n s t a l l a t i o n at U.B.C 106 107 6 Orthogonal 108 7a Plan views of 7b Sections through 8 Assembled v a l v e mold Ill 9 Slag melting HI 10 103 process of Mitsubishi Solidified the Heavy I n d u s t r i e s Ltd. 1 1 ' 1 2 ESC p r o c e s s views of the the v a l v e mold segments 109 v a l v e mold segments 110 furnace s l a g s k i n on t h e 104 105 v a l v e mold segments the ... casting CaF^AjZ^-CaO system 112 no IT Phase diagram f o r 113 12 Stainless steel 13 Longitudinal holes in the 14 Schematic of the 15 Macrostructure of V a l v e No. 5 (CF-8M) 16 Macrostructure of V a l v e No. 6 (316) H7 17 Macrostructure of V a l v e No. 9 (CF-8M) 118 1.8 Macrostructure of V a l v e N o . 10 (316+Cr+Mo) 119 19 Macrostructure of conventional 120 20a M i i c r o s t r u c t u r e o f CF-8M ESC v a l v e s b e f o r e ment ( e t c h a n t - o x a l i c a c i d ) ESC v a l v e H4 c a s t i n g s due t o m o i s t u r e sectioning procedure of casting the valves (CF-8M) heat H5 H6 treat121 20b Microstructure ments ( e t c h a n t 21 M i c r o s t r u c t u r e o f a s - c a s t ESC V a l v e N o . 5 , 6 a n d 7 (etchant - o x a l i c acid) 22 Microstructure of heat-treated 7 (etchant - o x a l i c acid) 23 Microstructure of ( e t c h a n t - KOH) 24 M i c r o s t r u c t u r e of heat t r e a t e d c a s t i n g ( e t c h a n t - KOH) 25 Microstructure of ( e c h a n t - KOH) V a l v e No. 9 i n 26 Microstructure of ( e t c h a n t - KOH) V a l v e No. 9 i n h e a t - t r e a t e d 27 Microhardness indentations 28 S c h o e f e r ' s diagram f o r determination of s t a i n l e s s steel castings66 29a V a r i a t i o n o f C r , Ni and:Mo a c r o s s t h e d e n d r i t i c d i r e c t i o n i n V a l v e No. 9 a t t h e edge 29b V a r i a t i o n o f C r , N i and Mo a c r o s s t h e d e n d r i t i c d i r e c t i o n i n V a l v e No. 9 a t the c e n t r e . . 30a V a r i a t i o n o f Cr'v.;Nf and ;Mo a c r o s s t h e ' d e n d r i t i c : '"' v: ; d i r e c t i o n i n c o n v e n t i o n a l c a s t i n g a t t h e edge 30b V a r i a t i o n o f C r , N i , and Mo a c r o s s t h e d e n d r i t i c d i r e c t i o n i n conventinal c a s t i n g at the m i d - r a d i u s 30c Variation of direction o f C F - 8 M ESG v a l v e s a f t e r - oxalic acid) heat ESC V a l v e N o . 5 , 6 a n d CF-8M s p e c i m e n h e a t e d t o CF-8M 850°C conventional as-cast condition condition on s i g m a and a u s t e n i t e p h a s e s . . of C r , N i , and Mo a c r o s s t h e in conventional treat- casting at ferrite dendritic the centre.. 31 Composition v a r i a t i o n i n V a l v e No. 5 (CF-8M) 32 Composition v a r i a t i o n i n V a l v e No. 6 (316) 33 Composition v a r i a t i o n i n V a l v e No. 7 (316+Cr) numbers . '',*; Figure 34 Composition v a r i a t i o n in V a l v e No. 9 (CF-8M) 35 Composition v a r i a t i o n i n V a l v e N o . 10 (316+Cr+Mo) 36 Composition v a r i a t i o n in 37 SEM p h o t o g r a p h s o f a g g l o m e r a t e d f e r r o a r e a 1 i n V a l v e N o . 10 alloy powder in 38 SEM p h o t o g r a p h s o f a g g l o m e r a t e d f e r r o a l l o y a r e a 2 i n V a l v e N o . 10 powder in 39 EDXA p l o t s o f a g g l o m e r a t e d f e r r o a l l o y p o w d e r i n 1 and 2 and t h e p a r e n t m e t a l ( V a l v e N o . 1 0 ) 7. conventional casting (CF-8M) areas '. 40a EDXA p l o t s powder of inclusions i n a r e a s 1 and 2 and Fe-Cr 40b EDXA p l o t s of inclusions i n a r e a s 1 a n d 2 and Fe-Cr of inclusions in powder 40c EDXA p l o t s 41 Macroporosity 42 Macrostructure V a l v e No. 9 of the electrode 43 Macrostructure of the CF-8M e l e c t r o d e dropped 44 Inclusions in the and e l e c t r o d e t i p 45 I n c l u s i o n s i n the e l e c t r o d e p i e c e dropped i n V a l v e No. e l e c t r o d e t i p and t h e p a r e n t c a s t i n g ( V a l v e No. 9) 46a EDXA p l o t s o f i n c l u s i o n s i n t h e e l e c t r o d e i n V a l v e No. 9 and t h e e l e c t r o d e t i p 46b EDXA p l o t s o f ( V a l v e N o . 9) 47 Schematic to e x p l a i n the i n V a l v e No. 9 48 Macrostructure of i n V a l v e No. 9 in the centre F e - M o powder of the CF-8M e l e c t r o d e piece t h a t dropped in e l e c t r o d e p i e c e dropped i n V a l v e No. 9 ( o p t i c a l photographs) inclusions the in the piece parent casting p e c u l i a r pool profile peculiar pool profile dropped observed observed 9, Figure 49 Schematic of the tensile specimens used 50 Variation stainless 51 Photograph of small t e n s i l e t h e deformed and f r a c t u r e d specimen from V a l v e No. 6 areas of 52 Photograph of large tensile t h e d e f o r m e d and f r a c t u r e d specimen from V a l v e No. 6 areas of 53 A I S I 4 3 4 0 ESC v a l v e 54 Cracks 55 Radiographs of V a l v e No. 3 56 Macrostructure of of t e n s i l e properties steel castings .. with f e r r i t e i n V a l v e N o . 14 r e v e a l e d b y d y e - p e n e t r a n t V a l v e N o . 3 Top - HC£ e t c h Bottom ( N H ) S 0 4 2 57 Macrostructure of V a l v e N o . 8 (HC£ e t c h ) 58 Macrostructure of V a l v e N o . 13 ( H C P . e t c h . ) ' - . , . 59 M a c r o s t r u c t u r e o f V a l v e N o . 14 (HC£ e t c h ) etched f o r a longer time) 60 Macrostructure steel number ESC v a l v e of the 4 (top transverse section of a test etch part mild (HC£ e t c h ) structure of 61 Dendritic V a l v e No. 3 62 Sulphur prints of V a l v e No. 3 63 Sulphur prints of V a l v e No. 8 64 Variation direction o f C r , N i , a n d Mo a c r o s s t h e i n V a l v e No. 8 65 Variation direction o f C r , N i and Mo a c r o s s t h e i n V a l v e N o . 13 dendritic . — 66 Variation direction o f C r , N i a n d Mo a c r o s s t h e i n V a l v e N o . 14 dendritic 67 Composition v a r i a t i o n i n V a l v e No. 3 of dendritic Figure 68 Composition v a r i a t i o n i n V a l v e No. 8 69 Composition v a r i a t i o n i n V a l v e N o . 13 70 Composition v a r i a t i o n i n V a l v e N o . 14 71 Machined AISI 72 Separated surfaces along a crack 73 Hardness v a r i a t i o n in heat-treated V a l v e N o . 13 74 Hardness v a r i a t i o n in heat-treated V a l v e N o . 14 75 M i c r o s t r u c t u r e s A I S I 4340 v a l v e i n a s - c a s t and h e a t treated conditions; electrode in heat-treated condition 76 M i c r o s t r u c t u r e of AISI treated condition 77 Fractographs of large t e n s i l e f r o m ESC v a l v e N o . 8 78 O r i e n t a t i o n of the V a l v e No. 8 79 Ductile b r i t t l e transition characteristics V a l v e No. 3 and t h e e l e c t r o d e of 80 Ductile b r i t t l e V a l v e No. 8 transition characteristics of 81 Ductile b r i t t l e Valve No.13 transition characteristics of 82 O p t i c a l f r a c t o g r a p h s o f charpy specimens from v a l v e No. 8 t e s t e d a t d i f f e r e n t t e m p e r a t u r e s and o r i e n t a t i o n s a - TT b - TL c ~ E d - E ..... 83 Optical fractographs A I S I 4340 e l e c t r o d e 84 SEM f r a c t o g r a p h s 85 4 3 4 0 ESC v a l v e SEM f r a c t o g r a p h s charpy specimen of i n V a l v e N o . 14 4 3 4 0 ESC V a l v e N o . 13 i n specimens of AISI c h a r p y s p e c i m e n s and t h e , of heat- 4340 notch charpy specimens from in the charpy specimen a - r i d g e area b - micro-cracks of different regions of a .. xi i Figure Page 86 Soviet electroslag cast valve 87 Schematic of 88 Electroslag casting of a flange 89 ESC v a l v e w i t h t h e w e l d e d i n s e r t 90 Macrostructure 193 t h e methods used f o r of the making h o l l o w for ESC v a l v e s use i n v a l v e bodies ESC v a l v e w i t h t h e w e l d e d i n s e r t .. 194 195 1 ... 9 5 196 xi i i ACKNOWLEDGEMENTS I would Professor guidance Alec The the are assistance And the Canada Mr. and of the of of course my technical am Sciences the to Sidla, I his Metallurgy the Gus sincerely for extended finally, Natural thank Mitchell, Department particular of to throughout Thanks of like is and American research friendly of this fellow for research their students helpful of this suggestions. department, in appreciated. financial Engineering Research and and project. the Iron for supervisor, assistance graduate staff greatly thankful my Steel assistance Council Institute. of 1 Chapter 1 INTRODUCTION With nuclear the industry, ceptionally creased are products a and Remelting other process wide process years. ESR h a s for is been the trolled overall by the service. was has only The been high common remelting material The processes' very by has in- components result i s , as might conventionally used Over prior the early (ESR) the be made to instal- Vacuum Arc as mid- the extensively in the process, last on. fifteen industrially-viable quality material.in objective behind processes was chemical possible high advantages of low ex- the as an with for Remelting as and r e l i a b i l i t y Although new. of metals testing conceived established components, of rigorous relatively quality the yield. pass these aerospace and The rejection range. both quality Electroslag s o l i d i f i c a t i o n . offset of high it the specialty; rigid. production composition of in of of specifications more to when hand, producing life fail century, development is rate (VAR) thirty years, high for of The and fail nineteenth the standards more which expansion demand tremendously. expected,^..- last and the high becoming lation growth rejection the that refining cost of of and con- remelting increased rates, a service and high 2 I n i t i a l l y , for of upgrading ESR was gained years the the air-melted extended prominence it ESR p r o c e s s became or to in evident better applications the cast ihgs. This led to speculation as ESR process can be extended produce the final step in this slag Casting or logical (ESC) Generally, ated with metallic produce scale only the increase cost process with the most of as as involve heavy defects it same the and equi- and forg- the very close shapes). to The next the Electro- components are associ- porosity, and hence of these can a the better unattractive. not only possible defects the small mentioned to ones, above The to they are castto a hot small working eliminate material, properties produce and to However, but and possible quality mechanical non- recent limited applied step as is are this ease it poor with expense. be large have Although capital produce anisotropy is was of squeeze-casting, castings, makes recent not emergence cast properties. quality in net shrinkage, ( f o r g img :and r o l 1 i n g ) casting shapes the segregation such and the ESC such mechanical better was or use process castings whether (near conventionally inclusions, processes extra sequence the techniques, to the the During conventional product Then process. defects anisotropic ing forged U.S.S.R. ESR m a t e r i a l to to in and also. valent cast the used material. countries; that than widely quality forging other was with large are but and the castings free manufactured from 3 at a comparatively used of low The E.O. Paton the ESC p r o c e s s applications. grams to very cost. Institute to in produce These range Kiev, U.S.S.R. components from large valve bodies, gears, etc. weighing for dentures r o l l s , has a extensively wide weighing pressure variety a few vessels, 1-2 crankshafts:, ; Figure Numerous 1). examples of several these are tonnes (see published in the 3-23 literature. like The valves, reactor pumps, nuclear has been ESC tubes manufactured have HK used by sections, been produced. diesel the for of header tubes 9 ' duty for diameter to area boiling several produce with some of components industry of J a p a n . reformer varying 'I' industry 3-9 occasions. beam rolls and gears. up 160 tonnes have 1 0 - sections is The in 1 been They 2 tubes section, ESC a p p l i c a t i o n to water petrochemical Corporation and crankshafts been r e p o r t e d Union. Heavy on Tubes crankshafts, engine the for petrochemical (YOZO) Another 1 1 and the 2). fuel-hand!ing fittings Mitsubishi Figure of Soviets ESC m e t h o d oval of the (see manufacture by steam plants fittings the alloys, and power reported and production in elbows, have in the production weight has 4-7 6-7 meter Raton a l s o reports' the rolling Other of and t h e y a r e p r e s e n t l y i n use i n the Soviet kiln-ring g e a r s i n s i z e s up t o 1 5 0 t o n n e s 1 8 13 of the s t e e l . reported kilns 5 _ are reported manufacture 8 > 1 of to be in ESC r o l l s service. for use 4 ESC a p p l i c a t i o n s include die blocks in ' in ' 4 alloys similar to shape, ' cast ESC to by cision cast a hobbing pressure It is or most no Hence of work it cutters from is or of for cold reports has been the done in of determine if properties ing codes, constraints. from Tl shape, above available aspect ASME/ASTM close stainless working promising the made the l i s t producing considerable the cast to the and M2 17 gun finished tool tubes, o steel, and steels 18 pre- nozzles vessels. prospect hot H13, austenitic evident any and semi-finished in on promising that the dentures without Hll finished operation. are this of ESC i n d e e d shape It Soviet is also origin North importance to investigate of the North American l i t t l e America. process ESC p r o d u c t s obvious and in Remelting offers components field Electroslag given that this and qualify economic to under manufactur- 5 Chapter PROCESS The vacuum electroslag arc consumable ature process in is through of a Detailed electrode into heating an liquid process region the arc, slag CHARACTERISTICS process in that and it the the operation use the a high-temperHowever, the they heating resistance and of a the WAR, w h e r e uti1izes electrode to processes mold. Unlike ESR p r o c e s s similar through a water-cooled between of is both melt mechanism. the accounts AND remelting remelting solid differ DESCRIPTION 2 ingot heating surface. ESR p r o c e s s are avail- 24-29 able the in literature. same shaped in as as copper heat ESR p r o c e s s water-cooled Figure made the The 3. one or mold. of a aluminum:- generated in high shaped the slag is water-cooled mold in directional, formation of the metal pool, in the liquid and uses illustrated of through metal the the inclusions drop, metal as the it pool. a slag to Joule tip and the in the manner. sulphur, place traverses The into solidifies respect is water-cooled pole. progressive takes composition electrode liquid casting with and other a schematically desired melts which non-metallic ESC p r o c e s s pool from and the the pool phorus that is metal the is mold molten of ESC p r o c e s s source drops refining the current metal a of electrode molten fective fall except This A consumable pole concept during through A continuous Efphosthe the shell slag of 6 solid and slag this casting ,i s gation; built smooth up pattern. brings the the progressively by a All this Remelting Almost all the broadly 2.1.1 another, ones which large of under sound s o l i d i - macrosegreremoves related poro- to con- virtues the the chemical those related to solidification quantities of low in the starting can be obtained that by one reasonably of the to earned its name even when isotropic most be Refining from sulphur, the can categories: Chemical important the the is inherent the level re- removal of this of is 31 ' highly Of structure. most using process. one refining. The material. at properties two to has ESR, has, mechanical related ESR p r o c e s s on of following Related Which Materials 1iterature 30 and and defects those characteristics. blished eliminates Characteristics the the affect Characteristics fining other A vertical a minimum; Process existing extolled classified The and casting. casting castings. Properties the to solidifying nearly effectively cracks the these the to Affect or and surfaces hot Electroslag point mold mierosegregation shrinkage, ventional 2.1 between provides fication sity, forms Very basic effective mechanical low sulphur slags. ways It of properties is levels well obtaining is through estagood 7 32-35 sulphur control. results of a amounts of sulphur. series fracture in sults uniform in many directions. in low ladle control deciding steel for clusions the of and is properties. literature which of actual mechanism deal inclusions from casting is the by exogenous is very low. be in obtaining type, the are size, content few de- the the in- also mechanical in and refer to inclusions metal and level controlling available very Hence other optimum inclusions oxygen of are in achieve important inclusions water-cooled indigenous to and electroslag present advances improvement, non-metallic during primary sulphur impurities, the d i s t r i the are remelting. mold, the remelted of for re- control. an Removal sulphide dissolved shape overall of being possible to step. size recent the ESR m a t e r i a l , a is sites three the significant f i r s t the in process. the material by of varying and ESR with inclusions (formed the references which However, it many in shape with toughness initiation inclusion residual in solidified of the importance Although removed most distribution bution oxidation the detrimental considerable are considered against only containing their that lowering provides and shape longer or fracture characteristics sulphide although sulphurisation of technologies, no the steels control and is shows sulphides noteworthy levels However, the cases, is 4 ESR 4 3 4 0 Since steelmaking sulphur of of fracture It sulphur factor Figure either As the chance material de- deoxidants) 8 and/or s o l i d i f i c a t i o n cation) are present (formed by p r e c i p i t a t i o n i n ESR m a t e r i a l . shows t h a t t h e e l e c t r o d e i n c l u s i o n elusion content of the i n g o t , during solidifi- Some o f t h e e a r l y content affects but i t i s well work the in- accepted now, 37 as are Mitchell points out, that identifiable metal pool there deoxidation oxygen the r a t e s a r e used. metal present, The l i q u i d content inclusions In t h e l i q u i d unless high the s l a g . characteristic of the l i q u i d O C very has o n l y d i s s o l v e d i n near e q u i l i b r i u m with freezes, inclusions and d e o x i d a n t no i n g o t electrode r e l i c s . ' a r e few i n c l u s i o n s and d e o x i d a n t s liquid oxygen as u n r e a c t e d virtually Of) of the a r e n u c l e a t e d and O ~l grown i n the ingot l i q u i d - s o l i d zone. gives rise o f s m a l l , g l o b u l a r and d i s - persed lower to a f i n e inclusions. than deformation formation inclusions (percent shape importance 2.1.2 process i n ESR i s much inclusion Characteristics their Related upon sulphide u n i f o r m de- of remelted mechanical in rol- Therefore, the steels i s o f prime behaviour. to S o l i d i f i c a t i o n to the conventional have an inclusions be a n i s o t r o p i c . content on n o n - u n i f o r m I f the i n c l u s i o n s (e.g. elongated will effect i n a r e a ) than elongation). i n determining Contrary This fraction have a g r e a t e r reduction material), ductility non-metallic volume ' air-melting practice. (percent anisotropic led The t o t a l the best Generally, background ' When Structure c a s t i n g processes i n which 9 melting tional heat and casting steps, during gradients blish a the the and slow rates melt character thin of slag dification free of f i r s t l y which due levels the structure or microsegregation to low mvcrosegregation a leads rates lead pronounced Also with to the the spot to esta- condition rates). Such thermal gra- formation of metal. which etc. is These the s o l i - practically This also such as segregation, efbanded and brings minimum. s o l i d i f i c a t i o n . structure and of insulating inhomogenities macroscopic melt is to hot-cracks, macroscopic freckles, due growth off to shrinkage, addition controlled the wall a be opera- temperature to mold lead by the low the structure rate and between conditions different solidification secondly eliminates melt can and porosity, equiaxed rate pool fectively librium pool and Hence gradients possible slag the Although step. directional thermal are the skin and separate characterized solidification high across is solidification progressive by two ESR p r o c e s s the (obtained dients represent as a the very increased least to fine dendritic system high deviates melt rates and from lead microsegregation. microsegregation structure, hence An good to equian optimum mechani- 38 cal properties. In conclusion, properties to good and it can isotropic., chemical refining be said behaviour and that of the the enhanced mechanical ESR m a t e r i a l solidification structure. are due 10 Chapter. PRESENT In Dr. the Alec latter part of Director of U.S.S.R. Division ESR T e c h n i c a l A 10-inch and non-destructive ' 4 The 0 chemically nally and viability was in up alloy to the at to in-depth U.B.C. tonne. stainless The The at Medovar, Institute, in the valve the ASME body casting Kiev, U.S.S.R. Evaluations the that Boris made among Westi nghouse Paton WEMD. of initiated of are destruca v a i l - quality requirements and as failed origi- workers. the a Dr. was meet Soviet ESC p r o d u c t s , one and by study installed ings indicate mechanically to of testing results predicted Hence U.B.C. was U . B . C , and Development and tive 9 (WEMD) at evaluation program Metal lurgy body for 3 a ESC v a l v e sent a b l e . WORK 1974, Mi t c h e l l , P r o f e s s o r of Electro-mechanical 3 properties simple and furnace furnace steels from is has both and the process inexpensive capable made of ESC making valve-body wrought furnace and cast- castings cast elec- trodes . 3.1 Furnace Detailed has been Design account reported of the previously. d e s i g n and 4 1 operation of this furnace 11 The cooled mechanical electrode aluminium of a rail part holder I-beam from a chain this in electrode The The f i r s t also voltage 2.5 one The is at variable which guides from having a speed 0-163 part rated 250 250 a fixed to water- the is suspended controller gives a (see of Figure two single input 25V - down V 60V of in of transformers. input phase voltage range and 5). step 12500 using inside reductor is of vertically carriage KVA w i t h range can move a speed consists at of variable mm/min KVA w i t h over a consists are The second transformer rated dry 600 and 600 type and V and steps of V output about V. The panel operating which not parameters only shows secondary voltage but the electrode travel. Also, the mold cooling Valve Mold Smooth vertical discussed directly water also be monitored primary has a and from the secondary digital a multichannel counter control current to thermometer measure shows temperatures. Design surface f i n i s h , solidification unique can the and 3.2 design framework. with electrical output. is speeds These drive conjunction the carriage guides. vertical single of and features of flat tops shaped and bottoms, products ESR i n g o t s . a t t r i b u t a b l e to or are s t r o n g l y are All of i nfl uenced controlled some of these by mold the are design 12 and operating ted with heat the parameters. manner primarily ingot from casting. of its the high overall also for into and to-shape viable and layer, design Cremesio ESR m o l d s et used are the a the mold with the shape. make less of adds to some ex- to because substantially of be Since molds aluminum the solidified copper a copper formed particularly sections. copper costly out has is and discussed made metal associa- dissipates pool Fabrication This contoured fabrication of as is 42 This product. problem been al . design assembly molten has cost of mold mold mold and d i f f i c u l t the inventory unattractive, was to considered a to castbe a alternative. in the slag the conductivity. mold Gear fully the optimum thermal ESC m o l d s costs 25 the presents welded in of which ESR m o l d tent-.by Mi t c h e l 1 Most in The castings U.B.C. gear using The mold a water were cast aluminum channel roughly mold positions calculated to were and made success- dimensions give a maximum hot- 43 face temperature this, an aluminum of 300°C mold for during the casting ESC p r o c e s s . of valve bodies Following was manu- factured . The pattern. Figure valve The 6. mold was orthogonal Accordingly cast views the out of of the complete aluminum valve valve using body mold are was a steel given divided in into 13 four segments valve the and two of shows the 3. 3 were the The is any at is There the In CaF^, furnace a in applied ing of poured CaF the into given in The Figure Besides this, one top the on and the accommodate 7a-b. mold. a 2 and slag. the base of One is draw- Figure two other 8 round at the molds and as the melting crucible all CaF 2 an to a arcing employed Both the main slag plate. with starter 'molten-slag' furnace and is the block to i n i - start and processes were arc the slag mold employs to which is a the forms through (CaF ) and 2 the component, (see added heating water-cooled due base the well. start the copper process, start. initiate When round practices known equally then plate the different slag two a water-cooled system. to between two graphite power molten sectional the 'molten-slag' electrode of valve. the 'dry-slag' graphite is of on to worked melted has of to initiation are the they the is the is and sides depressions placed placed process. other tried is damage electrode tiate flat mold. mold assembly used. - the Procedure valve prevent used for cupped are valve valve Melting whole sections assembled of molds with segments molds bottom plate molds these section the two inlet/outlet ings To - has Figure i.e. 9). This single-phase 'furnace a and small pool resistance heat- melted, is electroslag it furnace 14 is energized. added After the 'dry-slag' similar to and electrode. the of these ses is is mold applied is CaF the and is 2 the continues f i l l e d mold, tinuous are the The is the up components are t i l l a Either of one that it the the energized, CaF is established by melting enough volume of of the molten After components dry power causes slag pres- electrode This heating. plate mix- Then path metal compressed between is a starter such plate. current resistance remaining is with casting solidifying lowered furnace large of used. annulus electrode. lowered metal and being have solid as it resolidified terminated of is be of the pellet starter the turnings all (CaO, slag the Ai^O^* added. castings shell the a short-circuit sustain electrode power utes. to melted, etc.) slowly run, slag between can electrode When of placed surrounding walls. generated bed turnings against the across The the metal t u r n i n g s .under the L^O.^ the into is a Alternatively and turnings the slag remaining start, electrode and used poured the the CaF2 the and the slowly. In ture this a slag (see the taken smooth which Figure melts and the mold metal. At the end is withdrawn electrode out after surface forms 10). about due to between is of the from thirty min- thin, con- a the mold and 15 The main duction of operating valve castings operating primary 3.4 melt the a slag source, finer.' of of 44 The 3000-4000 for simultaneous importance choice process. It - metal correct for generation most functions the and the kg/min. important is it choice ESR component required must act container successful upon A Process the medium, rests (electrical ESC perhaps remelting Therefore heat - is pro> A 0.8-1.0 heat-transfer prime a) current pool the 36-39V 200-260 Slags during follows: current of electroslag number as rate Selection The were established voltage secondary - parameters of as and slag to in ' f i l l a heat metal re- . . composition operation. following: transfer characteristics conductivity, thermal capacity of the and slag thermal conductivity). b) slag phase perature, c) The with metal more properties viscosity, refining important reference to - (vapour surface slag the above pressure, tension characteristics of . is (chemical points selection. and are liquidus tem- density). composition). discussed below 16 tant The ternary and universally ESR. Fluoride CaF and t i v i t y 2 small CaF CaO - + additions system slag decreases the solidus and A«-2 3- It has been to pure decrease in conductivity Mitchell and Cameron fluoride ion contribution 45 of showed to CaF the liquid. that the this a The occurs total ionic of liquidus conduc- that produces impor- field electrical observed 2 most the increases A ^ O g the in and U is system viscosity, of the M^O^ applicable generally temperatures of - 2 relatively substantial work of because mobility the is re- 3duced by through complexing the 2 effect rare earth fluoride ing in A&OF,, and A£0 F 2 2 . This would be reaction A* .0 This it + 3 is 4F" > A£0 F " 2 also seen oxides. part of fluoride + A£0F~ + 2 2 A£0F~ addition ions charge 0 ~ + addition complex as A£0 F " the However, the ions in 2 of of by silicates and CaO r e p l a c e s the oxide carriers, ions thus of releas- e . g . , 2 > AJIO3" + 2F~ 0 " > AJ>0~ + 2F" and This produces an 2 increase in electrical conductivity but this 44 increase the is addition efficiency. not of substantial. A2- 0 2 3 leads Low to electrical higher melt conductivity rates and higher by 17 It has Aj^Og in cause A £ 3 2°3 £ also the expecially the in of of CaO. an of by the dissolution This acid/base is of be- reaction: a slag containing overall melting CaO time and efficiency. temperatures attained directly the .slag components by faster decreases region stability slag much the high the rate 2AiO" This increases the presence essentially dissolved thus that the 2 CaF^ alone. to in ° ~ than Due higher + is 46 noted dissolves n 2 hence thermal been CaF^ is A and also should below the components have a low during the melting, electrode, should vapour be the high pressure. i.e. Also 44 it has been of CaF^ through A£ 0 2 can cause Si0^ and An melting noted the + 3 that 2 3CaF will = = 2 shift have 2A£F in similar essential requirement medium is that it must that of the least 100°C below solid phase on that of the face quality freezing m e t a l . of of CaO d u e to volatility reaction significant H 0 production 4 the 4 ' 4 ' ' which These castings. + 3 3CaO AJ^O^/CaO ratio. Presence of effects. for the have metal, has a a slag to liquidus but must melting conditions be suitable temperature also point lead a to form higher good at a than sur- 18 The 11. 48 From tures CaO of the diagram this the should The of phase it can slag, be for 2 be seen in the refining power conditions, deoxidation, and CaO i s that for equal primarily of as (a.c. a Figure liquidus tempera- of A& 0 2 and 3 system. are course used in proportions slag mode shown low characteristics composition, is 3 ternary slag refined. 2 approximately present metal CaF -A£ 0 -CaO a or the complex d . c ) , metal function melting that desulphurising is being agent. 44 It has been suggested that (RE 0 ) to the ternary regions in the phase 2 3 compatible 20 with diagram of a rare-earth-oxide CaF +CaO+A& 0 2 where ESR p r o c e s s i n g . of 2 the leads 3 physical Besides to wide properties strongly are complexing and presence basic F~ of Taking slag (hence are with steel for content above CaF low alloy 50% 2 CaF 0 , to leads sulphur in selected (AISI , for 15% 4340) strongly Both these stainless steel we two different steel and low had A s ^ where a very low sulphur had 15% CaO , the ESR. stainless 15% CaO a reactions. consideration, For we also points steel required r e s i s t i v i t y ) , for were , to electrical desirable castings. 70% is respect highly the the complexes n compositions alloy increasing (RE-0-S) ~ behaviour conditions and system addition 15% A £ 0 o o , 20% La 0 9 q 19 As the the castings hydrogen main basic slag, and the one is low electrode so hydrate the + 2 is the to to basic 2 low [0]+ partial condition) hydrogen liquid metal pool, would Of slags are ions these the last sufficiently by (e.g. today's slags pick-up used con- from because the such - the transferred + which obtained slags (at hygroscopic, from hydrogen OH" residual to [2H](at slag the the pressure promote of surface) metal. slag-metal 0^ in transfer Fe of interface) (as in hydrogen metal Careful molten ^=^-0 " a Also of be that importance. because basic ^ — 2 0 H " 2 two can Highly formation H 0 this deoxidised the contents if the fact of the electrode. f i r s t the prime ESR a r e into the easily. of atmosphere slag the subsequently 20H" According as in and control was the of increased promote this content practice. 0 ~ and of basic careful castings the hydrogen is highly hydrogen serious CaO) atmosphere of through melting taining the humidity hydrogen not slags in the were deoxidised, sources transported steel used were content Three is slags slag storage, start preheating, technique are a prefusing, few ways to and using avoid the hydrogen 20 in the slag. creating a the by on slag a.c. Hydrogen dry from atmosphere a shielding melting has the by atmosphere simply hood. also Application been during ambiguous electroslag series Utilizing lems were slag-start was severe bottom claimed to ternary remelting, molten-slag in technique of slag to the in diagram was create dry start used, 2 2 70%CaF /15%Ca0/15%cU 0 tate some 2 2 the but of d.c. hydrogen these were an not slag 3 the did prefused of solve or the in this not holes even in the double The 11) could showed precipi- easily eliminate the hydrogen Figure could prob- when problem. composition and slag However, problem (shown 3 hydrogen longitudinal Using solidified prefusing surface 50 technique, the several did that Therefore by superimposed reduce castings. CaF -A& 0 -Ca0 CaO w h e n the of ' start the castings. of reduced experiments. encountered enough half prefused the not dry of be protecting 49 content can rehydrate. hydrogen in the casting. To in the avoid dry-slag ficiently so hydrogen high susceptible CaO was start, used ture related the to directly moisture, and in porosity due to components temperatures. preheated were problems CaF were 2 and moisture were La (C0 ) 3 the condition. 2 were 3 hot was observed. heated Aj^O^, preheated in to calcined No the to slag suf- which are 500°C while at 800°C. traces of not These mois- 21 Although it castings were taken avoid made to of sponge) due was tion of hole, argon and subjected two was cast ings the next and has steel the had a more small and and been divided steel (AISI valve 4340) precaution was A saffil shielding holes at the side one additions the melting made in (CF-8M). testing - through the for addi- the other operation. low alloy All the (NDT), steel valves (AISI were macroexamination, testing. with into and hood ( A ^ O ^ > f i brous for were the two castings valve the middle steel deals with in the mechanical section slag, holes in during stainless the the hole alloying castings that atmosphere. This non-destructive stainless alloy from in lined passed microexamination The moisture and valve to the indication steel deoxidant Several clear hydrogen used. and a to stainless electrode 4340) was evaluation parts. while castings. Part part of valve A deals B deals castwith with low 22 Chapter EVALUATION A. STAINLESS Five two were 1.5% STEEL stainless made from OF ESC VALVE VALVE steel CF-8M max. S i , 0.04% max. 9.0-12.0% Ni, 2.0-3.0% 4 CASTINGS CASTINGS valves (0.08% S, Mo) were max. 0.04% made. C, max. electrode, Out 1.5% P, of max. these Mn, 18.0-21.0% one from 316 Cr, (0.08% max. C , 2.0% max. Mn, 0.03% max. S , 0.04% max. P , 1 .0% maxsi,' 10.0-14.0% from 316 chips the additions of was duce bar who CF-8M bar last done to This does was with 316 and have rolled addition rolled 316 bar bar keeping in electrode the Mo) of view controlled powder. that to even 316 The CF-8M f a c i l i t y available one chromium chemistry casting readily bar, from ferro-molybdenum the done with 2.0-3.0% controlled change not a manu- can pro- rolled composition. this, ventionally cast given double with one castings Besides The with Cr, ferro-chrome composition. facturer 16.0-18.0% rolled and alloying Ni, was a properties of ESC v a l v e s . a CF-8M after block refining quenching this (12" in x 16%" A0D. The treatment conventional from casting x 17") heat con- treatment 1094°C were was (2000°F). compared 23 A typical stainless 4.1 electroslag steel is Remelting Table I shown casting in Figure Log for Stainless gives the melting valves made by istics noticed the the a valve ESC conditions Some melt or body made in 12. Steel ESC p r o c e s s . during of in Valves for of 5 the the stainless special castings steel character- are as fol- 1ows : Valve (hence heard no hot towards section slag and crushed large tudinally They could its run. avoid any porosity in However, the the bottom Figure moisture also 1.3). being be for due to As of a of due a slag was for moisture in was was about prefused sectioned, running longi- 8 inches prefused, the monoxide in slag casting of discussed the pencil) abrubtly explosion be to the the responsible carbon minor will distance the interrupted a CaO), when diameter be This (particularly (about were the holes were evolution due low. to in- deoxidation. electrode added end use. Valve the to of for sufficient had the from of Melting because To observed.(see - cycle) components holes chances 5 topping 4.3.7. the No. the No. was 6 not the mold over the slag. was The long beginning Also - of covered The casting was enough. the from run the incomplete Extra to aluminum avoid top ;sectioned : casting and CO powder was evolution argon again because was passed showed 24 longitudinal holes were holes. due to Valve to increase prefused were had the holes - point content the was certain However, to chromium of the moisture the considerably. due it Electrolytic avoid holes. were 7 chromium to decreased this that the moisture. No. twice some At size As rehydration casting. problem and but in were The of added slag again density mentioned of chips was there these holes section 3.4 the CaO i n the fused precipitated slag. Valve temperature in the The No was Valve added to feeding The porosity 4. 2 the feeding was powder appropriate does the and - slag avoided moisture problem porosity 70% Fe-Cr and Fe-Mo and rate uneven was probably segregated this Testing not the related chromium in components to of high moisture was observed. complete. which observed U.B.C. of 10 Non-Destructive As the No. Heating before) sound arrangement ferroalloy - trace increase casting. 9 (mentioned slag. casting No. have ultrasonic in 65% molybdenum contents because resulted pockets in powder of in an was of inadequate clusters the the of casting. No casting. (NDT) the f a c i l i t y testing for for heavy radiography sections, two and 25 CF-8M and valves one 4.2.1 were for ultrasonic Dye The externally Penetrant stainless valves were the surface Ultrasonic Ultrasonic then ing on to a section steel ultrasonic The ASME half valve steel sonically than degree attenuation the noise too most instances grained this was a to three tested inch with It and showed the full testing a that the note that are more d i f f i c u l t attentuation these section 1 MH,- 3/4 the increases in detection of of low-alloy or to one for heavy 'no useable (CF-8M) austenitic ultra- forgings. section areas, The size; may be- indications. inherent alloys: machine diameter accord- penetrate steel from and i n c h e s . . . : ' 'heavy with austenitic inch 7-3/4 discrete results with that isolated of done austenitic also generally was indicate from or ESC v a l v e specification depths normally thick a at carbon microstructure The 388-71) received permit this on results casting similar great A Test forgings level, come longitudinally used. performed (ASTM was stainless and was casting. specifications of radiography sound. forgings. steel sectioned system was SA-388 resppnse stainless was testing ASME for Test sectioned the one Test dye-penetrant 4.2.2 - testing. conventional internal evaluated 1 cut In coarse Following surface transducer. The 26 penetration It was direction s t i l l was questionable transverse to whether not fine defects could have been three inch section, or the grain orientation. could be detected. Although in the a better direction results of indicate austenitic the that 4.2.3 ..Radiography Radiography could be 4.3 in a ESC testing is not accomplished these suitable for valves. Test was performed a in cobalt-6'0 accordance source. with No ASTM apparent E 94-77 defects detected. The Testing conventional longitudinally cut 4.3.1 steel using Destructive were grain ultrasonic stainless specification penetration out and through (see (DT) ESC v a l v e the Figure middle 14) for castings and half were inch destructive sectioned thick plates tests. Macrostructures The etched about half vin 1 an 65-70°C are shown in the chilling inch thick acid solution for 1-2 Figures effect plates (38% hours. 15-19. of the were The The surface HC£, ground 12% H S 0 , 2 4 macrostructures grain water-cooled structure mold and and macro- 50% H 0 ) at 2 obtained clearly almost shows 27 vertical solidification essentially free of pattern. Figure the This of topping change the casting. cycle of and pool can be profile structure in piece electrode which Figure This 18 shows casting was ferro-molybdenum are believed two eases The tudinal will se.c.tiion o f 19. though there casting. between the feeder be due the top or The the of is some columnar riser and of the area columnar This placed other is at plates tests. the of equiaxed thought this were these zones to casting. be and inclusions of casting a These the is equiaxed the and due given at to cut up for in grains edge banded longi- of the structure an angle either position. then a subsequently. near shows the part by structure be operation. additions. quarter CF-8M to a a ferro-chrome and covered also in shows and melting discussed top is corner at hot- 17 believed ferro-alloy and the Figure is melt some inclusion scattered the are interrupted hand during conventional and slag an addition the macrostructure macro-etched examination This during to the surface. a centre.. identified Most This structures easily. right the a to top with macrostructure Figure to be due inclusions powders to shows dropped big made was the the some 16 corrected in peculiar of the s o l i d i f i c a t i o n d e f e c t s. a l t h o u g h p e c u l i a r i . t i es:'do e x i s t . top Also, micro- a 28 4.3.2 Mi c r o s t r u c t u r e s The by ACI austenitic closely stainless cast wrought they are The higher alloy. are not stainless corresponds steel. alloy cast The and considerable and optimum the wrought silicon and chromium and nickel - the they ductility castability composition, but also on on ranging in perceptibly amounts in 316) of CF-8M) to ferrite can Besides ferrite be for hot the other. lower and cold be magnetic a to 316 of the than in small on the but one hand principally lesser (fully (due the type working to CF-8M forgeability Depending non-magnetic in may optimum history present AISI contents chemistry for as on extent, austenitic as substantial austenitic matrix, as produced. production improves grade content provide from phase in thermal microstructures Type designated to variations trivial steel of sound weldability castings, and improves presence the of delta- resistance to 51 hot cracking resistance during to casting corrosive operation. :media. such It as• also improves sulphurous and acetic 52 acids, to intergranular attack, and to chloride stress 53 corrosion stress and cracking. tensile Delta strength ferrite values by also a increases the proof dispersion-strengthen- 54 ing effect. reason for From CF-8M (this higher the castings will chromium above is be we see essential discussed content that to in later). is the real CF-8M. presence obtain This of good delta-ferrite corrosion in 29 resistance and mechanical of delta-ferrite to accelerate in properties. austenitic However, stainless steels the presence has been shown 55 Sigma phase the was formation f i r s t of an intermetal1ic detected in Fe-Cr-Ni sigma alloys phase. and reported 56 in 1927. It has been magnetic, intermediate occurring in elements The many and has formation of r i t e - s t a b i l i z e r s Although also this form been such sigma of by a formation the 18-8 than with forms of ferrite being sigma ferrite to chromium formation maximum The about percent and a range molybdenum and and transforming to sigma austenite relatively comparatively diffusion where sigma surrounding austenite. short from chromium time by adjacent This is The a in in alloys about in less delta- content, concentration chromium-rich depletion eventually shown at that high nucleated. ferrite ' of retained occurs region tem- transformation 600°C to 950°C reported can and formation been ' fer- it time- temperature and 59 s i l i c o n . ferrite, is ' of of of the literature. rate a a on structure theitransition 47 58 addition formation has areas of 3 by from described 61 as of the non- crystal molybdenum It through in to in readily curve. regarded 2 alloys enhanced Sigma be hard,brittle, tetragonal hour. in chromium most 60 can ' C with the one-half ferrite is type delta-ferrite, 850°C is austenite. typical a documented chromium, forms and a ternary phase as as with and well sigma perature-dependent diagram phase binary phase from identified results Figure 23. of in the 30 The tic effects stainless of sigma steels are on the most corrosion serious in behaviour highly of austeni- oxidising en- 59 vironments creases such the decreases in CF-8 type or specimens itic of and at low room particularly severe network with in- strength, around the the but and ductility when above discussion, ferrite and sigma phases to eliminate condition by a alloys o i l . identify The 1120°C ferrite pools. Many suitable used heating heat for at heat at and sigma austenite have differentiate was been sigma austenitic polishing and and stainless etching sigma phases in important stainless phase present was treated and was quenching The con- quenching heating in the water. essentially thematrix in austen- dis- eliminated. cited in phase steels. procedures 1150°C adopted throughout is treatment. solution treatment phase sigma to and it the heat the 1100 hours distributed Sigma in treatment 1-2 after techniques and are in any were the from 63 ferrite phase temperature the microstructure in tensile of involves to continuous ring sigma temperature and cast which water The both continuous castings as-cast dition in the valve the nearly consequence identify steel strength, Loss is general 2 In to a In strength, resistance forms grains.^ impact acid. yield temperatures. corrosion phase nitric hardness, the elevated as literature other to phases occur- 65 ' Two used to ESC v a l v e s . different identify the 31 In to the f i r s t 5 microns, (133 ml 8-10 minutes. acid solution found etch the then acetic to attacks outlined present within only of and is a left the microstructures cast and heat-treated 1 the micron second and H 0) several were etched 2 100 nu solution in (56 from to gms the to the to is 3 specimens KOH, 100 sigma conventional oxalic in and shows the as-cast it is severely. is The eliminated F i g u r e s 2.1 a n d valves in were solution the 22 as- polished (HNO^ disturbed metal. (5 1 m£HC£, sigma were phase. gm 2.5 a reddish-brown Austenite is not attacked. was kept at acid, faintly 10N few in they is in to casting HC£ pjicric Ferrite V for to Then electro-etched at and yellow CF-8M acid predominantly phase specimens m£ w a t e r ) phase sigma was respectively. acid the is Similarly the the relief for oxalic 20a-b valve attacked different reagent outline in V wt.% the Figure which the behind. remove 28-30 10 and CF-8M up phase a mixed bluish-grey. the from that This rapidly. conditions in at 3 clearly shows procedure, Cr0 ) procedure very from V i l e l l a ' s Then stains ferrite men times ethanol) outlined. this etched gms polished solution seconds. phase show chromic-acetic in sigma ferrite mechanically electro-etched phase phase were in 25 specimen the show In were phase specimens ferrite water, ferrite sigma the specimens 20-30 ferrite clearly and the the The they 6 V for microstructure treated 7 ml Then at the electro-polished acid, outline condition. heat one, KOH seconds, and the One 850°C specifor 32 14 hours the to above promote sigma procedure. Figure this specimen. grey regions are the grey area the austenite. formed was is from received CF-8M within shows in the given austenite are in the treated specimens condition. Microhardness ried sigma out to confirm phase from metallic sigma diamond pyramid phases. The what DPH. also than Figure 9 This 24 the As as-cast Sigma tests phase on that Figure has is DPH v a l u e s phase phase but the DPH obtained be in for and phase .26 solution- eliminated. were hard and also to car- be and inter- of the austenite from sigma the of Figure identation literature because trans- Sigma the the calculated 255.0 could in sigma - light micro- distinguished DPH the microstructure actually on dark casting ferrite austenite been the been the detected. 643.3 quoted has condition. - value value and and with of conventional completely shows indentor which the valve is 27 phase, only easily sigma what hardness shows same etched sigma-phase, that in the was condition, 25 is it microstructure the Figure from difference the austenite shows the then ferrite seen. boundaries phase. the are solution-treated microhardness lower shows The metallography austenite The is relative sigma and untransformed No. ferrite 23 regions present. ESC v a l v e the black ferrite structures a The formation these phase which are is is indentation - some750 taken 33 here is value over is a within Delta 4.3.3 The steel network a large Ferrite It becomes of the alloys ferent of has Quantimet. - Ferrite sigma delta ferrite while the literature particle. ferrite a in discussed therefore, The instruments particles isolated been essential, castings. sigma Measurements importance cast of content briefly in to determine content Ferrite austenitic was Indicator, was also stainless the the last ferrite measured by a Gage, ;Magne estimated from section. content three and difa the 66 Schoefer's The ferrite piece diagram. Ferrite numbers between been adopted rite content. to two as ferrite number does results numbers As content, The due obtained the were Ferrite done was oxidation. from related at low different Indicator a i M a g n e - G a g e was used on content ferrite which correspond surface to The index closely calibrated ferrite numbers. accepted not magnets the particularly Measurements examination. eous ferrite Although content, uses 'bracket' the ferrite rite. Indicator to Table II to to in out has the fer- percentage used the the the fer- for avoid the 'brackets' find test percent to shows locations only the contents, specimens polished known number actual precisely rough of quantifies ferrite the to microerron- ferrite castings. the ferrite specific 34 ferrite content magnetically pointer and which were similar tents obtained II. the than would it the be ferrite can be enough ing. in as was Hence the stainless bags particular duplex and in the as-cast from bags to and is the were quenched cycle to heat in that strongly the in residual influenced subsequent cooling by rate. and result within anomaly were heat- oxidation. not fast before some seems From are 1 ower quench- sigma phase. agaiin wi t h o u t that ferrite ferrite the of heat-treated was bags lower given 6 This valves the It 5, phase excessive treated are opposite the showed water. resulted an of con- number numbers specimens s t i l l even, condition three open an castings sigma avoid the cut microstructure specimens these numbers. ferrite condition. history a conditions. valve of The ferrite heat-treated thermal d i f f i c u l t for presence of provide the Normally, the steel indicated*^ alloys the in average that the quenching thermal been perature to specimens that the has due stainless it in to to indicates ferrite heat-treated condition. by found and in works attached specimens. the also reading grit locations noticed bounda r i e s Therefore It be 320 all gives contents The to dial specimen to as-cast as-cast specimens. was can explained treated III The test various the expected the It in d i a l . surfaces from ferrite in spring polished Table table coil the and this calibrated of clean casting instrument content specimens each a This a The 7, has castings. on ferrite Table the moves the in of the this content. content solutioning of tem- 35 ments the Another point is the that casting is probably of the hot is slag tor for forms and it normal a to mode to this accuracy to variable cut 'snow' and lower the technique the casting. rate of the has been terminated as thermal acts a This top run is part a brief the insula- freeze. also done using by the using was found in the Quantimet. at higher the be reduced resolution, values use that it or by but this to differrite contents using in any considered was noise which of de- The ferrite 'snow' the technique It not of there The was of part run, threshold results. topmost measure- the to out can ferrite of done section. set in the mode makes turn other be the more necessary study. Theoretical was was the bulk and were particularly The sophisticated in the metal the cooling end slowly etch d i f f i c u l t cut' the of good the slow after part work d i f f i c u l t leads very and last mode. 'ground it the net than measurements get is lower A stain in a of Towards last Quantimet. to content solidifies Ferrite f i c u l t ferrite the cycle the scribed from to casting. blanket emerges much due topping which also estimation carried out using of the the ferrite Schoefer's content diagram. 66 Schoefer cast has Fe-Cr-Ni developed alloys with a one-line which the constitution ferrite diagram content of for the 36 alloy can be position. metal. estimated It The was derived Schoefer's ferrite-promoting all austenite through the of in Figure 28. using numbers elements use austenitising power by also Schoefer's estimated obtained each Magne from the alloy requires conversion the 'chromium into 'nickel element. gives the diagram. can diagram particularly at of all and ferritising diagram calculated It weld equivalents' the The com- for equivalents' representing Schoefer's Gage only diagram elements of knowing Schaeffler's into coefficients Table M i l the from diagram promoting or tents accurately be are is ferrite seen con- the higher higher shown ferrite than ferrite those contents. 62 Tensile that the data strength generated levels content. Comparison ventional CF-8M casting tained Magne Gage Also, by Schoefer's heat-treated rite as the is diagram are 4.3.4 It has been microsegregation the to mentioned affected results to the in C.F-8M:; s h o w s the obtained by as-cast on the as conob- those rather workers. than residual solutioning twice ferrite content found earlier by to ferrite that As much fer- temperaferrite Mi c r o s e g r e g a t i on frequently in levels applicable 1300°C fi 7 1150°C. Interdendritic that on related is greatly from workers strength similar Q u e n c h i n g f/runr quenching other directly showed condition. contents ture. of are by c l a i m e d ^ ' ^ electroslag 9 remelted that interdendritic material is greatly 37 reduced from casting. lead an that In to the general, low optimum in equivalent low melt rates microsegregation. melt rate is section needed and in conventional small As mentioned to achieve cross in sections Section least 2.1.2 microsegrega- t i on . Microsegregation analysis cast of samples condition) heat-treated areas and samples with across etched they were ratio' minimum and line scan concentration ratios Out of all of the of the the along such three ratio obtained elements from the the of along while they and analysis. with Table The molybdenum is the in selected analysis were apart!. marked The (Cr, b and con- 'segre- gives of was show solute segrega- show most to Mo) a-c the results the Ni, 30 the marked 5 mm variation IV as- composition elements 29a, the (in were maximum analyses. analysed, traversed etched Figures microprobe line, the casting Before that alloying samples. the in before the be (in performed direction. samples as were to microprobe castings CF-8M scans lines repolished (defined in Line electron valve conventional indentations the by CF-8M dendritic composition) determined a) the photographing gation tion the studied two condition). were dition, the from and microhardness After was t h a t - highly 38 segregated b) c) the from the conventional castings the edge. of This has a is a Austenite grows i n i t i a l l y is dendritic cludes into as ferrite the shows a the and So phases line due scans from it at and the does seen In the of alloy ferrite been by of delta ferrite. of melt ferrite in the between a directly inter- phase in- austenite true picture from the one an here the enrichment as which solidification determined present chromium the solidification end an stages r e p o r t e d . ^ the that in forming Three dendrites solidification be the represent the elements from element. interrupted of value not not of residual alloying depletion phase. at segregation can is in segregation does have precipitation most the .process. end than distance delta steels the then castings. because with ratio segregating here, ferrite consumes hence to corresponding austenite of and to from the partioning microsegregation and ferrite areas. defined delta back precipitated the From of the equivalent heavily stainless austenite transition ESC v a l v e s the solidification 18-8 segregation in structure during chromium. of depicted a then centre an is and the microsegregation precipitation of for as duplex in lower which ratio, or the clearly interdendritic f i r s t ferrite is segregation solidification there much molybdenum precipitation in to is interdendritical1y and edge Microsegregation consideration form nickel increases true The by microsegregation The of followed Interdentritic ratio the element of liquid. of nickel would expect opposite effect 39 is noticed. mined from 4.3.5 the to valves optical a and the emission electrode is bottom and composition of tion advantage However, volume of which at the This casting regions of was V-X the comparison. deter- or f e r r i t e . analysis carried show can between average seen the the using along be of out the castings It difference longitudinal in the slag in determined above. The results segregation are the by with the in is in of low might this is with that the there electrode top chromium, in 31-36. the s o l i d i f i c a relatively macrosegregation. because of the the - conventional analysis bottom mentioned and side molybdenum, definite castings the during small. nickel, No rather same potential and to the these also composition to in occur oxygen is the radial ESC v a l v e s Figures observed gives surface and respect variation given trend and Generally was carbon centre segregation 1 material approximately composition operation.^ composition as-cast results casting and be austenite composition Tables ESR f o r Macrosegregation side side conventional for within should Macrosegregation spectrograph, sections. melting to side composition conditions change and ratio casting. pool small occurring and composition The small segregation Analysis different negligible the the segregation Composition Top ESC Therefore, and macroithe to 40 variation be of noticed chromium tive elements is that from From 33) it can obtained be by operation. nickel from the of chromium seen composition chromium during a and the melt variation resulted (see is in due unstable the feeding a to the ESC m o l d . During noticed that the funnel small and powder be the dislodged probably the resulted could but also not pockets in frequently manually. powders. tion was melt the This was in This sudden not only agglomerated completely solid of used the to to to casting. vice versa. (see Figure easily the be melting in Valve powder with No. 10. was the in was appeared as latter volume and it flow had rate quantities composition of used. operation feeding large a were the funnel uneven magnetic powders.from in the Two rate the of mechanism powders. feeding clusters The feeding melting an resulted into nega- composition handle additions and in feed the jammed led 7 can observed predetermined was No. during inadequate with tube of 35). A vnbrators a and ferro-molybdenum feeders long at Valve can deviation content was which corresponding variation vibrator funnel set a chromium Figure to point uniformity of and is in molybdenum ferro-chrome only positive mean variation that a there reasonable valve which content, The is However, In The there addition to added small. controlled respect this mean of the very wherever the deviation is powders to and of varia- which large inclusions point is in discussed 41 in detail later The come can use this be in of section a better problem produced chips). and (as feeding a in sound Valve It is firmly composition to ACI CF-8M will not and molybdenum 4.3.6. arrangement casting No. believed 7 with that the by any easily uniform of of AISI addition of insuperable over- composition addition converting composition present with would chromium 316 chromium production prob- lems. 4.3.6 Problems As bdenum With outlined was above made Nos. while ferro-chrome Although could be could not be that the they that in the the were of casting addition with easy be of seen and Electron clusters areas 1 alloy of were and and powder with 2 at did not No. melt 10 been (SEM) From Valve 7 No. the same ferro-molybdenum Observing different No. composition chips, have ferro alloy 38(a-d). in moly- of Valve uniform Valve these in added and and operation added were Microscope the chromium casting ferro-chrome of Operation of chromium identification. F i g u r e s 37.(a-d) ferro chips macrostructure can Scanning photographs shown the solid ESC addition and f e r r o - m o l y b d e n u m sound, inclusions the electroslag Chromium achieved for the 10. with In photograph under a made additions. large and During controlled during Valve 10. 7 Alloying (Figure marked these it on The obvious SEM magnifications these it can completely the areas became powder. 18), be but are seen instead 42 were loosely cast material. as a dendritic in Figure der, The areas both and show powder To areas very 1 shows nounced as ones the 1 and 2 be 2 are shown peaks for from of in Mo 1 2000X Fe-Cr EDXA peaks, 2. in 'or Fe-Mo the they and pow- 'parent Areas 1 Although From Cr molten magnification 39. Cr. the Dispersive on Figure in partially Energy and and richer at is with. Mo and areas much it pockets' been observed results Cr 'small have analysed both are to whether The distinct metal' areas were and 'parent that can (EDXA). forming seems identify shown Analyser metal' together structure 38(d). the X-ray sintered are this Mo than 2 the not it and as is pro- obvious the parent metal. To Cr or areas were determine Fe-Mo powder, 1 2 and in shown similar Fe-Mo in to are expected ferent of of as the 1 in the 2, in 40. Fe-Cr with Mg. Fe-Cr different Fe-Mo Fe-Cr basic in is are on Fe-Cr graphs it for areas in 1 and powder. by lining other and powder that is the very inclusions could entirely in hence is inclusions This two hand 2 The generally powder Fe-Mo seen Fe- in Fe-Mo the be is present and and can produced the 'pockets' composition. produced dolomite Fe-Mo, in the inclusions powder these present present and EDXA Fe-Cr From in original The inclusions ones material non-metallic completely and the SEM. and processes. Ca the also Figure the furnace contain in area composition arc and analysed present are whether an the in be dif- electricinclusions produced by 43 aluminothermic reduction morphology and composition shows the material that consists . To of Cr the in and the 1 Mo a r e certain and that metal completely One tion as (m.p. also 2 is, the would powder did it not the the inclusion different. pockets to melt in Table also had about Cr 2 This basically = because 1900°C, heavier. and that m.p. So formed The Cr 2 and Mo much contents more valve I n i t i a l l y , ferro- show From which Fe-Mo the results 13% M o . that this Cr did were obtained and it than not Mo melt casting. would of its higher of 70% Fe-Cr the and results The powder the 1 The 70% C r and in areas comparison. contain expect Fe-Cr for 65% M o . 54% and XI. given pockets normally is microprobe. about 1 method, ferro-chrome formed 65% F e - M o because in another about areas compared of had have and are powder that it by shown powder and hence completely present electron ferro-chrome areas is and powder. this the parent molybdenum is Fe-Cr confirm analysed for of process question agglomerates as in not go in melting = point 1650°C) to why solu- and Fe-Cr preference to 44 Fe-Mo of can the that only Fe-Cr the be answered powder feeding used rate F e - M o . ' ( 3 0 . 5.-. g m s / m i n . red because earlier 4.3.7 in of Problems there was immediately could have mold ever, the no and in porosity have been of the as inside a leak were cleaned trace any could the was have was of ESR o p e r a t i o n , Another this the particle powder Fe-Cr These of the size and than powders also for inclusions been a as occur- described the the does slag not however, which layer a does process and is more much source to 41). should electip the gases the to be must explo- the certain serious of the When threat How- secondary causing cause the near pressurised present it Another due was casting leaks. in 5, mold for sectioned Figure No. melting the porosity probably entrapped Valve The removing found. (see of Operation water-cooled inspected was ESC mold. the a macro porosity melting problem and in operation After electrode under Although in for the in were electrode exposed, released s t a b i l i t i e s leaks the cast the Fe-Mo Electrodes melting surfaces sion. the Cast effect. there than higher feeding this Therefore that gms/min). caused indeed piping 4.5 explosion of fact larger much Using terminated explosion trode. the 4.3.5. end a minor was vs. With the was unstable Section Towards the the by safety in- avoided. was encountered 45 when a cast etching top Valve right cture electrode part was a into the the this shown and structure the parent has a the The to the the different ones tip. of cast therefore by piece a inclusions than the present in the parent the the this 43), went through alone method, electroslag electrode, to rehas the thermal enough to grains. or less cannot similar distinguish However the piece casting of that electrode is casting. electrode structure casting' Figure more and different (see the area To photograph 'parent is dropped composed polygonal 17). thought had This cast into is this the stru- operation. the chemistry the is in Figure it entirely piece conventional in from is electrode and (see piece) from Although piece different structure. while structure electrode was non-metallic rode dendritic cut seen electrode electrode and be structure a melting piece grains dendritic this can the structure. composition electrode the The the was reveal noticed casting electrode macro- was having the and consideration, an electrode polygonal casting between the dendritic which into piece It profile of during a to casting. coarse convert pool sectioning body centre (possibly 42. pool foreign point etched of crystallised normal a the metal Figure the cycle body After unusual also in used. speculation in the an latter liquid repolished is and foreign confirm 9, observed Taking that No. was the morphology would but particularly as at be much similar the of to elect- 46 So parent the casting, optical from inclusions microscope the electrode through optical (multi-phase) of the EDXA. The electrode The b) the tip from type and the of The shape tic the entirely tip the to are because the a composite average examined was size in under determined electrode given given observed larger. the are an inclusions have also figures very in piece,the Figure Figure by 46. 45. . : The fol- - from much the electrode alike except piece that and observed the nucleated they size in is the much parent casting smaller. and grown in the intersect delta ferrite Also interdendriwhich forms interdendritical1y. c) However, the piece electrode of casting is point the • latter. inclusions have in observed the is in the as inclusions casting these tip were found are different appear region above of shows although tip piece, examined inclusions electrode inclusions of 44 the compositions in Figure All parent bigger were electrode inclusions electrode tip) morphology from (electrode the mentioned the of are they and the deduced they is SEM. composition and be The the piece areas kind can and areas electrode similar corresponding lowing a) and three SEM a n d the three microscope. inclusions The the and from which confirms that sitting in the composition of these it middle is of actually the inclusions. a valve Figure 46 47 shows that both inclusions In fact tion hand, which their of the is has from is points in and the the is very from the peculiar pool profile and similar. on have manganese. The basically speculation electroslag tip the composiother alumina-type absent. the dropped silicon casting, are completely electrode in parent They confirm the rich composition different. Silicon these piece significantly inclusions observed which are entirely All electrode overall inclusions; body the casting electrode is that the actually during the foreign a piece melting opera- tion. The to be an piece. the event The which occurred probable dropping events as a which th electrode piece F i g u r e 4-7.(a-.c.). T h e electrode was during process poor are the melting profile common served 59). in At as if shown the such a valve time qui te invariably piping) electrode being a and is a centre this detached to the is fallen thought electrode before are shown schematically in the in resulted cast in of an This 4340 after the in mold asymmetric Asymmetric AISI the and centre off-centre. pool was steel profiles also (see obFigure electrode fell off. This electrodes. The cast elect- porosity might due of casting place not from with the took 47(4). casting piece in result this Figure common have secondary in and electrode another i s apparently rodes of observed have (perhaps resulted melting by the in representing a slag piece of entering 48 the porosity. temperature 47(b). side zone As was After a was result suddenly rapidly. this The shifted of cooled pool dritic structure. The and it made or dus on the file area oriented a band is of fine side shown and and the pool profile Figure Figure position change dendritic the can structure right advanced the den- the left and affected pro- the and there the event. s o l i - pool that growing is the and to notice the Figure oriented represents through on off high (see liquidus The stopped which cut shifted to the solidus randomly was One have structure and 47(c)). 48. pool was and off, centre metal growth fine fell the liquidus a crystals random liquid with (see unresolved front the no " d i f f e r e n c e in dendritic fication a solidified electrode towards dendritic liquid l i t t l e of more this oriented left piece is s o l i d i Above observed. It this, has been 72 pointed ture out Jackson refinement changes in pattern. 300 by primary Metals series flow due be 0). d i f f i c u l t small with changes and the sudden low due steels) to having However to detect due after small the to in a growth strucrate change in of growth direction renucleate the change growth rate segregation as is the segregation CF-8M there increase will sudden in that anisotropy immediately case of elements C,S,P Mitchell direction stainless direction position to and they in in the the heat occur heat these are heat- flow. only in Comthe (e.g. elements present flow (e.g. new coefficients of and in would very quantities. It would be worthwhile to mention here that the presence 49 of the electrode detected which by are nuclear the it would when not if be such subjected to a it fatigue crack and parent 'defect' might valves the and ASTM gauge the diameter verse directions. 6 7 a (e.g. a site be the of would it is the which landing for very if of component for piece even properties properties would were carried (ASTM gear valve. How- would be of air- an nucleation the present of electrode a piece different. given for 49) both The results Table for in XII are f e r r i t i c and (given out casting A351-72 on A370-376). Figure in out casting. condition carried conventional SA-351/ASTM fatigue (see were requirements in potential conventional Tests the the castings test), Testing standards are to be Ultrasonic electrode but not Properties tests the an would and valve machined, occurs casting solution-treated and a the such stressing be as Tensile Tensile is casting Radiography fact valve valve qualify detrimental Mechanical 4.4.1 to In fatigue craft), the the the (e.g. used applications. removed 4.4 inside NDT t e s t s generally be ever piece the of and CF-8M) The The before in in Table for for for forged 0.25"in the the trans- Valve Valve Nos. No. The castings or to 4.3.2). and XIII. steel ESC in section tests those were tested longitudinal these the conformed samples were austenitic and from tests they while given samples rolled 9 5, and tensile (ASME alloy 50 steel valves ASTM A182-74 plete that all the the and in noted given given in in except for valve The strength. bodies The following ASTM/ASME specifications 316 (low The this and worked cast counterpart the of values and to non-worked the These cluded two tensile ASME/ASTM are in met. and the has it can seen (Valve ASTM No. code parts short be for forg- in high- used by 6) about 2000 two points should valve bodies and be are for rolled strengths not for a parts or are forged for cast a fine material rolled been in or forged altered to give order to ihcrease for loss the in 316 is a the CF-8M large strength strength due condition. adequately the 316 is also explain ESC v a l v e . properties specification This steel compensate points observed that of delta-ferrite thus com- content). composition amount for specified material delta-ferrite where strength the in The - stainless Hence and falls SA-182/ XIII. valve their valve The of and 316 to out 316 ASME (ASME 1. tables, the of reference Table Appendix for requirements service in these in sized ments also given service. condition. the are ESC v a l v e s tensile temperature are results castings made 2) high 316) tensile temperature 1) for the satisfy ings for specifications From psi etc. of the provided evident the So lower it can tensile be con- ESC v a l v e s 1 i e w e l l the if composition we consider within requirethe 51 properties creased the of from delta (CF-8M) and be that seen by about of on 9 conventional the in cantly has This be rest due only casting less to is be much reduction This in area can cleaner is area from the while no such edge (i.e. by has seen more decrease a by the is compared, of 9 it can is higher by things. Firstly casting The grain electroinclusions), solidification considering to decrease of observed of content, the non-metallic better percent part ferrite that the s i g n i f i - although fact ac- hand and is size point other casting the higher latter the and is the elongation centre No. strength delta the Valve is sensitive sharp to 9 are latter On in (w.r.t. be tion 9. No. of secondly percent and Therensa No. two strength. explained which in- the smaller. difference content. casting is by clusion in to casting are strength 24% a n d ESC V a l v e also was specification results casting conventional microsegregation structure. the conventional about the CF-8M yield due the the the the be yield of If CF-8M casting content conventional tensile demonstrated than can by to the while of higher area) lower can of the can content reduction slag average No. chromium increased). conventional (as the properties psi. for was the ductility this content specifications. ESC v a l v e counts the specification a b o u t 20QO p s i 4000 the 7 where the delta-ferrite than No. 316 tensile within higher the ferrite The also Valve the percent non-metallic in percent the in the in- reduc- conventional ESC V a l v e 52 From the delta-ferrite tensile content results of the it also castings became evident greatly that influences the the 73 proof stress clude that and delta-ferrite sile strength rite has a by gives to a a higher concentration harden tensile a in strength, about increases is austenite, yield the softer the than than the value. increasing phase the of carbon the stress work a l . case of fer- the it 0.2%, ten- The and causes con- and effect. nominal In et austenite strengthening due to p a r t i t i Q h i n g thereby proof the austenite stress 80% o f the Irvine strengthening stress greater proof values. increases dispersion strain higher strength strain to work and therefore the tensile due to delta-ferrite and nitrogen hardening to the rate. 62 Beck, Schoefer et al . c o n c l uded from t h e r e s u l ts from 62 C F - 8 M a n d 277 C F - 8 h e a t s t h a t t h e t e n s i l e a n d y i e l d directly of for related to the f e r r i t e longitudinal the tensile ESC v a l v e s . function of mined percent to by the ferrite strengths graph, the the latter the line. quite the of It ferrite and yield can be elongation) content. the When the conventional lies show positive a This significant about higher and casting has not 1000 psi deviation be a much of with the any the yield explained smaller the about by is a (as and plotted below on deter- the while psi fact size relation the line 4000 direct yield strength grain number definite tensile are of strength are variation ferrite ductility show average casting value could that However, does strengths F i g u r e 50 s h o w s t h e strengths seen content. former conventional content. about from is that than the the 53 electroslag This is the casting also obvious samples 2-1.5% from higher The tensile sized and the this results from the edge of fact the than the samples fractured and deformed samples exhibited material (see a that higher the from areas of Coarse stress. strength of c a s t i n g is about : the edge. the 0.25 characteristics 51). yield yield conventional away the Figure in of grain inch a . diameter large grain materials approach 64 more closely valid of the of result, the near a the tin, grains of 1 to the the also done on grain grained speciments, It found 7 4 in number very concluded rather work harden is similar, and limit is particularly in to of the is the absolute substantially the general the effect 75 marked. particularly In from the strength the case of rolled number by number grain of further of grains size which relationship. shows that the coarse less than the finer form of grains appreciably strength also a section free increased tensile aluminum in present cross grains. tensile it the affect increase that To relatively slightly than although obvious, the the 60-100% with and grains that that curves became of aggregate polycrystal 1ine specimens elastic few crystals. so size/ultimate grained strain number whole by cross-section controls too 20-30, He single required are increases refinement. the are Pel 1-Walpole for of sufficient surface properties Work behaviour specimen material in the of grain the 316 the stress- size on tensile the 54 samples, there that were diameter small To few specimens from gauge solution the did 6 final These sectional area have about results of formed sence 16 of clearly line. Figure and average value that of To both the of area both the larger speci- 49)„were machined No. as and 16 9 (CF-8M). were specimen and in the slip on surface broken the ends of was XIV. an the preare irregular samples area the.sample taken de- grains tensile a The shows the shows by cross- The projected measured the MTS section. s t i l l lines the should Table surface in prior therefore cross in in inch were before) tested larger 1 These mentioned times given ends properties. Figure the was test the (see measure the to of of fractured one tensile inch diameter fractured the 0.25 -gauge grains and of and a Valve are large properties bulk decided with were was were of is the photo- planimeter. as. t h e out- fractured The area sample. Comparison specimens 52. then was smaller the of surface, graphed for up the operation more The tensile same way the grains visible. fractured and specimens near the inches specimens times large in 4 the than A close shown (in these region it ESC v a l v e s cross-section represent machining machine. the specimens of the result (316) treated of in problem, size No. a not length Valve size grains As this Large a grain samples. mens.. to very overcome and the (see of the Tables tensile XII, XIII results and of XIV) the shows large and small that the yield 55 as well lower as the tensile strength than the smaller specimens percent elongation smaller specimens of CF-8M, both while sized expected. of ment which the in the the the is possible samples, could was and in the mechanical properties were machined section In all the of the three centre) that the tion in This shows from a occurred that to area this had than investigate the much undeformed in large tensile specimens from tensile samples (two the were yield area and large cal properties only the specimen The ultimate are- that and tested. results tensile marginally difference is rather in responsible than the higher for number of the samples and (CF-8M). one from XIV) percent the in samples the difference small in the show reduc- large of grains grip 9 Table treatment the in No. and in the quenching threaded edge than in small Valve (given was treat- grains the strength heat of for influence possibility region from or greater number what heat heating case similar to the the the difference in a much The to in was opposite the this lower the were CF-8M. similar CF-8M of the and was variation during specimens 316 for because specimens, So in and that the section. 316 completely of cross both is there have larger specimens c a s e "of' This the for larger reduction specimens. It size of of mechanicross section. In conclusion of the ESC v a l v e s if the chemical range. it can can be said that easily meet the composition is the tensile required controlled properties ASME/ASTM within the codes required 56 B. LOW A L L O Y Six valves 0.6-0.8% Mn, 0.70-0.90% 4.5 STEEL and Remelting Table Towards nected This and was the top so most of cables were not they were were connected) this problem 3. made the to A rare Nos. was moisture. these valves. A steel typical is shown to Only 12 electrode. up ESC 3, the cables started with by such the No. and carried for the high currents all further joining the base {La^Q^) oxide had composition and to Nos. the be 13 was rejected and 14 were of a valve These so cables and of starter after Valve No. was sound. could also plate castings, plate because measurements the Valve was con- and changed used. casting casting 53. (where was base cables. In by mold valves. smoking. the damaged. slag Figure as Ni , Valves contact carry C, 1.65-2.00% the electroslag in bar Valve lost dimensional Valve S i , of problems and (0.38-0.43% conditions heated was overcome The ESC in inside not earth any 11 were designed rolled 4340 melting 4340 0.20-0.35% Mo) casting The AISI melting current heated. without Valve the mold pi ate w i t h s c r e w s . No. S, AISI the the was using 0.04% for of because CASTINGS 0.20-0.30% Log end made P, XV g i v e s the to were 0.04% Cr VALVE 8 However, porosity be done due on sound. body in AISI 4340 57 4.6 Non-Destructive 4.6.1 Dye As the Nos. 14 3, 8 showed valve were Penetrant Valve other was due Nos. were and 13 did not cracks all over to improper 4.6.2 Ultrasonic,; Unlike present sonic 4.6.3 in any testing Radiography detected. 4.7 could two The crack. section one whole for to moisture, cracks. However, (see and This No.;. 54). these point Valve Valve Figure piece treatment. castings, in be This cracks will be dis- was ultrasonic 4340 showed valve testing. penetrated. performed were Testing sectioning AISI The that castings The results they were did full of ultra- sound. Test radiographs Destructive any tested the castings obtained The and due chapter. problems on porosity Test Radiography radiographs as valve thickness showed show heat this CF-8M 12 sectioned treated later section and valves heat (NPT) Test 11 cussed not Testing using the satisfactory of Valve No. cobalt-60 and 3 source. no flaws could are shown in The be Figure 55. (D.T.) procedure has been mentioned in Section 4.3. 58 4.7.1 Macrostructures The ()50% AISI HC£, 4340 50% H 0 ) of and shown from are Valve tion. No. in 60 the one shows a All the from The top part the cracks. the the was Also slag hot-topping pool indications Valve of the near being of No. (shown transverse the edge are longer on The with noticed Figure section it of the be seen casting) to can Cracks be seen. clearly shows also the be inshows due mold. to Some macrostructure the that is defects 59. must the From solu- indicates this from 13 mild of time) respect a Figure top and 57). can the 8, section free macrostructure assymmetric also in (surface a entrapment was the inter-dendritic) for off-centre this 8 in etched macro- 3, through No. shown The persulphate are cycle. profile electrode of a section as solution Nos. of macrostructures (probably (which Valve 10% a n i m o n i u m 14 acid hours. One-half transverse Valve an 1-2 from 56-59. in in for sections etched longitudinally that 65-70°C Figures running sufficient macroetched about 3 was ESC v a l v e . except was longitudinal Figure steel at 2 structures 14 steel macrostructure the grain smaller than size in centre. Specimens No. 3 were CuC£ , 2 0.5 distilled shown and in from etched gms in become mid-radius, centre 2 nu reveal 61(and). coarser and ; Oberhoffer's SnC£ ,350 water).to Figure edge, towards HC£, the The the solution 500 nu dendritic dendrites centre, (30 ethyl top gms but Valve F e C ^ * 2 alcohol, structure. are of fine they 500 These at the are all gm nu are edge 59 oriented directionally. men the from forming 4.7.2 top Sulphur ingots were shows equiaxed Sulphur as grains printing as from do any than those tent of to are the valve or very the in of random slow the speci- orientation cooling distribution forged Nos. 3 shown sulphur from the photograph dendrites reveals Valve These show (due rolled electrode. not coarse the at the top.) Prints well taken However, and in 8 is in Sulphur prints along a of segregation castings sulphur products. Figures electrode of with 62 and and the piece 63. The prints are indicating that the much than that lower valves lighter sulphur of con- the electrode. 4.7.3 Interdendritic Using the same technique microsegregation at was The determined. variation in of Figures obtained tion Mo 64-66. from ratio in Valve count. solute is Valve No. 14 The the Microsegregation the as low centre line Also the of scans Table analyses. 13 described of concentration maximum No. as is XVI From for Mo. low while the Cr, this count was segregation ratio of 4340 Ni, the we the value minimum Section ESC microprobe gives Also, no AISI the of in and valves along Mo are segregation see that the segregation could similar Mo in 4.3.4, be with shown ratios segrega- ratio given of for to the background Valve No. 13 could 60 be due was to the located 4.7.4 heat-treatment away from C om p o s - i - t i o n Composition and carbon variation the XX was of give the electrode due to Besides using tent the mined The by the 4.7.5 of Heat The by All the the dition. castings Treatment the and tests that the specimen machined nickel, hole. height 67-70, and while of appreciable in molybdenum ESC v a l v e s . analyses the The width Tables the XVII in of chemistry sulphur. the sulphur the was also electrode con- deter- using Leco Sulphur Analyser. XXI. From this can by material, was about even to starting change case of spectroscopy, material and the decreased we 70% when see through the sulphur low. Microstructures properties treatment Unmachined is of starting mechanical and Table content mechanical heat in the 4340 except analysis" processing the No emission shown sulphur electroslag content optical valve AISI Figures observed to chromium, along castings. is are in fact M a c r o s e g r e g a t i on composition "combustion results that the the the due and of elements complete and in shown remelting of variation studied are centre Ana 1 y s i s these castings the and/or of hence were individual steel the done are greatly resulting in the specimens affected microstructure. heat-treated from Valve con- Nos. 3 61 and 8 were austenitised were tempered at ment done each for property diameter 2 and and No. the tised in a tempered the Valve test given done that the cracks square quenched. exact in the The (see were They heat treat- mechanical much heat the machined casting Instead in Figure of of heat valves quenched. this treat- from treated treatment, inch protrusions) testing) heat 3 section Valve as a whole were austeni- They were the longitudinally, showed Figure 54) 59), than cut dendritic side of valves were tests. cut force. hole shown these oil on and also they valve separated not was show very fine when a when the also were surface. this structure did clearly and the from The up Macroetching interdendritic section and and the Figure cross is were Both cracks rather the mechanical 845°C (see vertical longitudinal valves was a valve a step. casting without shiny 14 with machined. destructive No. macroetched 72). oil The (through (for After These was the not these at 560°C. were and are shows was bath observed. crack 14 sectioning for When a and 550°C. machined 71(b) both salt at sectioned inch tests hole specimens 14, to inside 845°C and machined The Figure prior trant was diameter. Valve 13 were of horizontal individual Nos. 480°C set 13 a while valve. ing No. inch 71(a), about about section. Valve of at plates with separated such pene- concentrated surfaces any dye revealed A bar revealed cracks along were (see 0.5 smooth Figure cracks. 62 From the cracks above in results Valve No. it 14 can were be said caused conclusively due to improper that the heat treat- ment. Hardness tion of hardness valves. These shows a large width of the than not the as about to the 8 should two above be that it condition Figures No. due to 73 and out of the heat-treated Valve particularly a had inches in hardness cross section Valve 14 the variation in a No. along higher hardness 14 varia- the 74. difference No. 2% width the the to find shows 13 Valve compared is section thickness No. 13 (due hole). strongly machined Beside treating and surface Valve is to hardness, The points rough in valves. inches treatment. and This done height in casting. machined The shown In were the variation centre. the of along are large. between heat measurements these, cycle would to due be because it their other to to softer that final cross machine than valve shape advantages smaller easier is suggest castings prior include section the valve to heat reduced and in weight, the in the heat-treated examination, the specimens as-cast con- dition. For and cast microstructural etched and in 2% n i t a l . heat-treated The microstructures conditions are shown were obtained in Figure in polished as- 75(a-d). 63 The as-cast the quenched entirely and a of and tempered 76.shows it from that is structure site. seen while Some material (see improper ment of an mented in valve 4.7.6 not the inner the casting were again step in during present 12 and made, taken. At the test higher was treatment any of bainitic marten- done is on this largely process. on has might Heat treat- mechanical etc.) that due segregation 'normalising' effects believe a microstructure microstructure normalising, we have mixed area magnifica- presence that of is heat well docu- treatment of problems. Measurements dimensions was and quenched interdendritic This (homogenising the structure.Figure (dendrites) suggests composed microstructure interdendritic heat measurements 11, the tensile but for different shows This This steel in areas when literature, Dimensional Nos. The present. it. overheating would electrode. a while structure true areas also a dendrites. XXIII) - to 4340 the Same structure is light treatment, Dimensional casting is shows showed the darker important properties, the 13 in the Table heat AISI No. ductility contributed become ESC that bainitic condition from that the low coarse microstructure ferrite is also the a martensite. Valve than resulted to tempered specimen different tion has tempered specimen is condition 13. between were After the the certain measurements Also done slag on mold points between thickness the mold has been were the at and valve assembled, taken. same these After points points was 64 determined. 'pseudo below From percent and real are these data, shrinkage' listed percent in 'real were Table percent shrinkage' obtained. These are and defined XXII. Di shrinkage - Df - 100 2Ts Di pseudo percent shrinkage =. D i - Df 100 1 L where Di - inner dimension of the mold Df - final dimension of the casting T s - s l a g t h i c k n e s s . The 'pseudo percent shrinkage', practical significance mum value for mum 'shrinkage' this This is slag thickness 4.8 Mechanical 4.8.1 because Tensile As out on around is at the of the at tudinal tempered and 4.6%. corners very these determined importance is high to It and heat here, is foundrymen. was found edges that of The maxi- the maxi- of the castings. transfer and hence large points. Properties Testing mentioned AISI and as 4340 in Section ESC V a l v e transverse condition. 4.4, Nos. samples The tensile 3, were details of 8 and tests 13. tested the in heat were Both the the carried longi- quenched treatment have and 65 been mentioned Tests are were also given quoted in in at be a are not achieved certain transverse sented by by longitudinal the transverse tion rolled are values 150% at is vacuum is specimens. area less However if we level. plastic levels ductility Obviously deformation repre- elongation) to of that the the the and for (as of conven- o f % RA a n d than and in However, similar values been tensile strength consider respectively strength and percent or 90% h i g h e r have remelted ductility more longitudinal results particularly the and XXIII. included yield important, the which been treatments. ESC v a l v e s , in and are different heat is bar Table % Elonga- transverse bar hence had the been ductility a n i s o t r o p i c . ' .:. The mechanical drastically if treatment. When tested, lower the they AISI showed the (particularly 4340 , s t e e l is tensile exhibited strength treated properties the (Table microstructure. heat it as in results The In subjected to extensive tensile comparison. specimens same rolled also level the given have reduction and the 4340 suitable bar, are melted, important specimens. the tional for strength percent air AISI so 4340 Some for XXVII results AISI XXIV. remelted XXV t o The on literature strengths can done Table electroslag Tables before. as one very specimens poor XXIII). As of and from ductility » .'The mentioned piece presence subjected due bainite, drop to is Valve tempered No. Valve were at much related No. drop heat 13 even directly inadequate can improper values earlier, to ductility) 13 to was heat-treatment martensite and 66 some ferrite mens were pered) (see re-heat the structure showed sile in XXVI) 4340 and to that steel specimens tudinal verse show For tensile the specimens the small optical improvement eliminate tion cut The etc. from on the the AISI steel can be of seen values as obtain. reasons as of inch 0.75 9 stated times of larger these forged in gauge also large in possible effect the mechanical region the 4.4, are ESC longi- tensile steel are larger Figure area 49) than shown do small heat-treatment, large the NITS m a c h i n e . the small ESR trans- 4340 XXVIII(a)) over properties, of the (see specimens Table of the ten- the cross-sectional properties any AISI Section in ESC Table transverse diameter tested (given tensile for the in that ductility that tem- micro- forged similar noteworthy the 4340 (given properties it then longitudinal than can threaded the speci- present. values results in was ductility s p e c i m e n s , were 77. tensile XXVII fractographs to ESR 4 3 4 0 Table having them XXVII), because martensite of and lower is one same therefore Figure in best and To but It given the Table slightly specimens. perhaps hot-rolled tensile quenched recovered properties comparing transverse specimens were tempered tensile in individual (austenitised, only and of (given properties any the the When properties general, properties 76). treated tensile Considering valves Figure in not show specimens. orienta- specimens tensile The were specimens. 67 The results to the are rest. section given This does not in Table shows have that XXVII(b) , number significant and of they grains effect on in the are similar the cross- tensile pro- perties. 4.8.2 Impact Testing Standard Charpy V-Notch E23-72 specifications and and 13 also on AISI were done in from both longitudinal in Valve rode the Nos. while verse in tests are and thus ture and to tempered transverse and in 8 the the at Figure charpy in 3 surface plot percent determine the from electrode. The It very the Specimens were rolled tested longitudinal, trans- notch) and specimen results Each point broken fracture from and of notch all these represents d i f f i c u l t irregular. brittle tests elect- The was 8 bar the 79-81. from Fracture 3, 4340 shows tests. was Nos. directions specimens. fracture ESC V a l v e transverse 78 Figures least brittle and ASTM condition. AISI specimens to to charpy Hence versus estimate specimens it was also temperature Appearance Transition Tempera- the results Valve (FATT). From 3 of and conforming on bar' and No. tested. out rolled longitudinal fracture d i f f i c u l t 13 presented percent the a of average as and tests carried 4340 quenched Valve were orientation the 3 (having edge an the were impact the Figure 79 electrode, which it shows can be seen charpy that at the of same No. hardness 68 level, the better toughness the longitudinal values ESC v a l v e . rode are much lower for seems higher the be ESC from than longitudinal However, temperature to specimen than the the 80 longitudinal values the ESC v a l v e . Also for the shows the specimens Charpy seem to results the the from elect- transition the electrode specimens have of specimens with a the transverse specimens with transverse toughness tudinal notch difference (TL), could ness. However, istics of shows the than nothing from the be to from due to notch. Although with longi- can be said as this difference in hard- transition are at very low small than specimens edge the values show the toughness The (TT) the ductile-brittle specimens again due 8. notch conclusive be No. energy longitudinal transverse entirely reasonable could the Valve higher transverse This of from longitudinal the it specimens transverse specimens exhibit valve. Figure better electrode the longitudinal than the grain character- much superior as temperatures. size at the edge. The ductile-brittle No. 13 are shown No. 8, but the Table XXIX in transition Figure curves gives seem the 81 and to have FATT characteristics they are shifted valves similar to the estimated of to Valve Valve right. from the 69 ductile-brittle-transition the FATT is The No. 8 with electrode the are smooth istic of the notch shown in energy electrode, on the and the 83. ESC v a l v e with fracture. The other hand s h e a r 1','i-ps a r e absent mens the ESC v a l v e , the different very irregular present shown at The low the and the Figure are surface is smooth 84(a). These speci- show lips an character- samples from irregular"laminated at The 100°C. The exhibit fracture where ridges the difference electrode shear hand, and from electrode an Valve Figures great transverse other areas a the large characteristics. there is even in ESC are entirely surface vertical shiny. speci- is ridges This is are clearly predominantly present temperatures. distinguish same apparent. in Areas Figure Four mode the appearance 84(a). shown the specimen, general Figure are and in To of fracture that specimens the show and on show from shown and from structure from are There surface the specimens transverse specimens fractured high of Figure between They material. orientations longitudinal even, ESC longitudinal fractography The the fractographs various and mens. for optical 82(a-d) in lower characteristics. of where 84(b). different of failure specimens a broken were charpy 'cracks' The areas in or examined specimen very cleavage with different small fracture different regions u n d e r the SEM. is shown ridges is appear quite fracture in 70 characteristics them as were identified. ductile/brittle 'low', 'intermediate' ferent areas Area ridge and 1 - area. faceted areas where Area The are 2 This is 'intermediate Area the ridge due s t i l l to areas. 3 and 4 mens due cast from to the area can be - This is are the the are very as sides the flat some round dimples). of the coarse the below:- of as also large base dif- identified fracture' general areas) the is of ridge dimples area. with 'transition much This is area shows here energy the very finer. and but 'high comprises much The as zone' fracture'. lip fracture termed vertical (probably termed represents shear and There shows been fractures. energy at characterising have the seen. region this This The dimples These 'low is of 85(a-d) on microvoid-coalescence specimen. fracture' region energy the energy' observed This This coarse. Area the - the is they Figures mode fractograph..from with in is This flat 'high represents tearing some is or fracture - fractures, shown This Instead (all except that also the fracture' fracture dimples are area. shear lips area like Area 3, also the on but 'high the i here energy area. areas are ESC v a l v e s . f i r s t l y structure the of representative This large the ESC kind grain of size material. of all the fracture and charpy is secondly speci- probably due to the 71 Chapter OTHER Although ing of the valve needed in improved TRIALS two is major f i r s t of cast valves Much work done origin the and Paton and 3-5 of the made tion. The with the mandrel in the with Figure 87. ingots (not cussed to provide mentioned perties of useful in with of workers 86 lower the is costs ESC i s have of and hollow centre hole). again shown the shows the hollow U.S.S.R., and sent by in the an the upright and be as better. solid are of Soviet feasibility ESC here the position position. associated different 78 79 Bhat ' by Soviets inverted information would hollow aspect cast extent above to work manufacture this problems valves) some the with used valve The some is valves Institute, being the lead more cast- process. Figure methods valve electroslag some (i.e. other ' Paton two on the 77 process. in might interest electroslag of the that process, which of WORK shows viable areas area FUTURE work a capabilities The AND present bodies 5 with valve for evalua- fixed mandrel and the These casting of are moving shown hollow techniques have been dis80 Hoyle, and t h e s e might and to which of A comparative ESC i n g o t s of the the two study same methods of size prohas been 81 done by Paton ingots have a hollow valves et a l . , better would and their structure lower the and results show mechanical machining cost. that the hollow properties. Comparative Also, 72 studies valves should therefore taking into be account conducted the on hollow economics of and both solid the ESC process routes. The other area technique whereby joined fusion or process. outlet By shapes The to used in the ESC p r o c e s s . Then segment the replaced side. An in section can be been the this it made body. during is possible by the of to 480 is parts body the the are casting to join inlet/ ESC p r o c e s s more product technique diameter required auxiliary Hence final to a of with and the Figure of seen this that work was A flange a electrode insert shown main technique to pin preliminary joined an a the are complicated could produce mm.) or for be made. very large diesel engines ships.** castings was used prepared valve close have to have main (with Some of this (which are Soviets crankshaft welded the which investigations separately using flanges otherwise) where thick the similar valve 89. The casting the mold plate. valve piece done here was was placed casting was fusion shown of in the to shown had in the aspect flange Figure cupped with a in this hole made. this make but hole in to the act as casting of the longitudinal Figure 90. insert to the From main 88. side This macrostructure is is which segment study used This mold to is this valve it' 73 body is bably possible. be corrected. instead of work needed is the properties Both if they perties the The of A flange insert and this area the weld region appear techniques to be ESC p r o c e s s and and warrant they make the it more to the be the can main and pro- be placed valve. More mechanical studied. further the top therefore soundness from would at could joined should acceptable economics, fusion casting hence in these and incomplete investigation point certainly versatile. of widen view the and of pro- scope of 74 Chapter SUMMARY The results electroslag bodies. sonic testing valves, steel the The ally free sity in same used. to thus of which their corrosion clearly a viable tests the to inherent of that low alloy to produce although grain tool the to austenitic large important that technique show case applied an indicate ultra- steel ESC stainless size. Radio- qualify the castings. required show desired to avoid to the when becomes microstructure affects the secondly also Chemical essential that defects. f i r s t l y and treatment greatly is in be become properties. ings used castings the is solidification are Heat achieve be cannot due steel the above process macrostructures cautions cal can would stainless CONCLUSIONS Non-destructive valves graphy reported casting valve AND 6 an obtain good However cast content, pre- electrodes in step the poroare to optimum stainless mechanical essenti-; related important of are special moisture resulting composition ferrite castings mechani- steel presence properties castof and resistance. Although the interdendritic microsegregation increases 75 from the duced edge from castings. tion in This It in casting determined noteworthy in the (Cr, Ni, castings achieved by melting The easily tion for in Mo the CF-8M while the in re- stainless valve steel casting conventional condition. castings, however, occuring is conventional treated segregation it within was CF-8M The segrega- should be austenite or phases. elements the steel castings, section that solution Macrosegregation valve valve true condition stainless from the equivalent as-cast in of particularly tested ratio centre the is is the was ferrite the that casting. tested to Mo, is the values that of were significantly found to be a about the verse ductility same with a the CF-8M strength of AISI were Strength of level, 4340 the the the of if steel during ductility these lower the than values valves content. longitudinal can composi- Although slightly was be valves chemical range. ferrite ESC v a l v e s can the arrangement. s t a i nl ess codes of of elements feeding casting., function width uniformity required ESC v a l v e s variation and alloying of. t h e higher. direct of proper the the height ASME/ASTM within conventional the addition required of that Composition properties controlled show along small. controlled tensile strength C) operation meet is studies and was At trans- significantly 76 higher led than bar and forged equivalent a the did number significant perties in to d u c t i l i t y the these not of alter samples. better strength verse of surface the the impact estimated grain than FATT The rolled lower for the ESC m a t e r i a l size and as-cast casting operation the process and of code Although quality this need point and applications is a are where to of of the material. higher very not the material The than impact the Also due transthe The irregular pro- that ESC the show- does show material. fractured to large for the it should codes valves and joining of main valve body during the promising potential applications of investigation. problems casting, therefore area tensile ESC m a t e r i a l . hollow further two qualification it of components the At was the structure. casting cast much the of results rolled was of cross-section impact r o l - properties measurement of the individually ductility characteristics of Electroslag conventional measured the the ESC m a t e r i a l was the conventional strength the cross-sectional in on ductile-brittle-transition are the grains effect of transverse Increasing specimens that have transverse ESR s t e e l . tensile ing the need attention: ESC m a t e r i a l has be been shown permitted presently must require to to be The be be problem resolved. of used forgings. a high in Also, 77 if fabrication casting and of in the process be be on alloying cause tion cannot cess and by will the less be generic be that test made alloy of are therefore and forgings we to may on from cast ESC v a l v e s equivalent and can be to the heat or if product the can rather d i f f i c u l t if operation between a might ESC stock the beelect- code qualifica- become economi- costs. electroslag easily in electrodes. meet than for casting shapes treatment. better this. casting be such wrought substituted can casting valve-body can - is differences or the might testing steel proper This high simple in electrode process cast with lie the to the the that simultaneous electroslag However, say with accommodate not the appreciable due done question during established, used does castings? are feasible specifications penalty. such is should The ESC a n a l y s e s . be properties codes control. conclusion, can low a shape problem individual there In real additions and the controlled the rode cally the process qualified than final welding, However, but the the The stainless The required ESC commercial them pro- without valves castings any 78 REFERENCES 1. A. Mitchell: •'Modern 2. A. M i t c h e l l and A. A k h t a r : ASME M P C - 6 , ' E f f e c t s of M e l t i n g a n d P r o c e s s i n g V a r i a b l e s on t h e Mechanical Properties of S t e e l : e d . , G . V . S m i t h , 1977 , p.l. 3. V . I. 1972, 4. B.E. 5. B . E . . P a t o n et a l . : P r o c . 3rd I n t e r n a t i o n a l on E S R , P i t t s b u r g h , 1971, p.135. 6. B . E . Paton et a l . : Welding I n s t i t u t e , 7. B . E . Paton et a l . : on E S R , P i t t s b u r g h , 1974, p.239. P r o c . 5th eds. G.K. 8. B.E. Paton et a l . : on E S R , J a p a n , J u n e Proc. 1973, 4th International p.209. 9. E.F. p.62 a l . : 17 i n 'Vest Mashinost Ref.2). 10. A. U j i i e et al . : ' E l e c t r o s l a g R e f i n i n g ' , I n s t i t u t e , London, 1973, p.113. 11. A. U j i i e et ESR, Japan, 12. A. U j i i e et a l . : ESR, P i t t s b u r g h , p.251 13. M. Na Rabinovich et Kiev. p.231. Paton et al . : P. Braun et kova Dumka, B.E. Paton p.435. et 15. Demidov et Davleniem, Ref. 2). a l . : 1969, a l . : 'Special ibid, p.169. Proc. 1943, 197.8, p.86. Electrometallurgy', Paton Symposium Electric International Symposium Bhat and A. Simkovitch, Symposium !, Iron 4th International p.168. 1975, and IV, Steel Symposium on P r o c . 5 t h I n t e r n a t i o n a l S y m p o s i u m on e d s . G . K . Bhat and A. S i m k o v i t c h , 1974, a l . : 1 976 , 14. Nov. Report of E.O. Kiev, U.S.S.R. Dubrovskaya et ( c i t e d as R e f . al . : June Casting', al'. : 'Electroslag Casting', p.44 ( c i t e d a s R e f . 21 'Fonderie', 1974, vol. I s s l e d Protsessov Obrabch vol. I l l , p.173 ( c i t e d as Kiev, in Ref. 29, no. Metall R e f . 23 2). 340, in 79 16. G.A. Boiko vol. I, et a l : ! 'Rafinivuynshchie 17. I. Petram: Pittsburgh, P r o c . 3rd I n t e r n a t i o n a l 1971, p.108. 18. H.J. and Wagner 1979, Pereplary', 1974, p. 1 3 8 . K. BarAvi: 'Metals Symposium on Technology', ESR, Nov. p.420. 19. A. Mitchell et al . : Conf. Engineers, London, 1980, 20. A. U j i i e et #3,892,271: 21. B.I. Medovar et a l . : U.S. #3,892,271: #3,894,574. 22. D.M. 23. A. 24. W.E. Duckworth and G. Hoy1e : Chapman and H a l l L t d . , 1969. 25. A Mitchell: ' E l e c t r o s l a g and Vacuum A r c Remelting P r o c e s s e s ' , t o be p u b l i s h e d in E l e c t r i c Furnace S t e e l m a k i n g , AIME publication. 26. National Materials Advisory Board: 'Electroslag i n g a n d P l a s m a A r c R e m e l t i n g ' , NMAB P u b l . , 3 2 4 , Academy of S c i e n c e s , Wash. D . C . 1975. 27. R . H . N a f z i g e r and o t h e r s : 'The E l e c t r o s l a g Remelting Process', Bulletin 669, U.S. Bureau of M i n e s , 1976. 28. B.I. Medovar et a l . : 'Electroslag Remelting R e p o r t 2221 7 , J P R S , W a s h . D . C , 1 9 6 3 . 29. U. Y u . L a t a s h e t a l . : Translation AD 7 3 0 3 7 1 , f i e l d , Virginia, 1971. 30. D.A.R. a l . : U.S. Pats. #3,894,574. Longbottom: Schneidholfer: Kay: P r o c , p.87. U.S. U.S. 'Special #3 , 6 8 3 , 9 9 7 : Pats. Pats. Institute #3, Pats. of Mechanical #3 , 8 7 8 , 8 8 2 : #3,896,878: #3,878,882: 902,543. #3,804,148. 'Electros1ag Refining', 1 RemeltNational JPRS 'Electroslag Remelting', NTIS U . S . Dept. of Commerce, Spring- Electrometallurgy', 1972, Kiev, p. 6 3 . 31. A. vol. Mitchell: 7, no. 'Journal 6, p.563. of Vacuum Science and Technology', 80 32. A.D. Wilson: 33. A.D. Wilson: 106th Annual 34. R.S. Cremisio et a l . : Proc. on E S R , P i t t s b u r g h , 1971. 35. R.H. Elwell et a l . : ASME-MPC-6, ' E f f e c t s of M e l t i n g P r o c e s s i n g V a r i a b l e s on t h e M e c h a n i c a l P r o p e r t i e s of S t e e l ' , e d . G . V . S m i t h , 1 977 , p . 4 1 . 36. V.L. Myzetsky K i e w , p . 11 9 . 37. A. M i t c h e l l : 1974, no. 3, 38. W. H o l z g r u b e r : Proc. Pittsburgh, eds. G.K. 39. Westinghouse c a t i o n o f an 40. L.M. 41. G. S i d l a and A. M i t c h e l l : 'The D e s i g n , C o n s t r u c t i o n O p e r a t i o n o f an ESC I n s t a l l a t i o n ' , S p e c i a l R e p o r t to DREP/DSS, June 1980. 42. R . S . C r e m i s i o and E . D . Z a k : Proc. 4th International S y m p o s i u m on E S R , J a p a n , J u n e 1 9 7 3 , p.137. 43. A. M i t c h e l l et England, Sept. 44. A. M i t c h e l l : v o l . 20, no. 45. A. M i t c h e l l and J . v o l . 2 , D e c . 1971 , 46. A. M i t c h e l l and R . M . R e v i e w s ' , n o s . 5 and 47. A. M i t c h e l l a n d M. E t i e n n e : Society of AIME', v o l . 242, Trans, of July 1968, 48. K . C . M i l l s and B . J . n o . 1 , 1981 , p . 2 1 . 1 49. W. H o t z g r u b e r Kiev, p.161. Jose: ASM T e c h n i c a l Report System No. 76-02. P r o c . Conf. TMS-AIME Ferrous Met. M e e t i n g , G e o r g i a , March 1977. et a l . : 3rd 'Special Ironmaking p.172. and International Steelmaking Met. 499 Report Project 1972, (Quarterly), presented Cameron: p. 3361 . at 'The Qualifi- 1980. Warwick and Conference, Quarterly', 'Metallurgical Smailer: 6, 1979, Keene: on Report, 'Canadian Metallurgical 1 , 1981 , p . 1 0 1 . a l . : and 5th I n t e r n a t i o n a l S y m p o s i u m on E S R , Bhat and A . S i m k o v i t c h , 1 9 7 4 , p.70. a l : Paper 1980. et Symposium Electrometallurgy', Electric Corporation ESC V a l v e ' 1980. U.B.C. Committee, 'International p.231. Transactions', Metals the Metallurgical p.1462. I n t e r n a t i on a 1 Met:a.Is R e v i ews , 'Special Electrometallurgy', 1972, 81 50. H. J a e g e r e t a l . : P r o c . 5th International S y m p o s i u m on ESR, P i t t s b u r g h , e d s . G . K . Bhat and A. S i m k o v i t c h , 1974, p.306. 51. R.F. Steigerwald: 1977, p.338. 52. ASM M e t a l s 53. J.W. Flowers 54. F.B. less Pickering: 'The M e t a l l u r g i c a l Evolution S t e e l s ' , ASM M e t a l s S c i e n c e S o u r c e B o o k , 55. F.R. Beckitt: 'Journals May 1 9 6 9 , p.632. 56. E . C . B a i n s and 1 927 , p.166. 57. E.O. vol. 58. L. S m i t h and K . W . J . Bowen: Journal I n s t i t u t e , March 1984, p.295. 59. A . J . 60. C.E. Spaeder, Technology of 'Corrosion', Handbook, et 8th a l . : W.E. Edition, of 'Metal The no. 1, vol. Iron Griffiths: 33, vol . 'Corrosion', H a l l and S . H . A l g i e : 1 1 , 1 966 , p.61 . Lena: vol. July The 1 954 , vol. Iron and and G . J . C o x : Journal Aug. 1970, p.769. of F . H . Beck et a l . : 'Advances in Technology S t e e l s ' , ASTM - STP 3 6 9 , 1 9 6 5 , p.159. 63. E . J . D u l i s and and E f f e c t s o f Iron and 64. ASM M e t a l s 65. R.J. 66. 'Handbook of S t a i n l e s s S t e e l s ' , eds. B e r n s t e i n , p u b l i s h e d by M c G r a w - H i l l , of Steel p.143. In- Stainless G.V. Smith: 'The N a t u r e , Occurrence, S i g m a P h a s e ' , ASTM STP 1 10 , 1 9 5 0 , p.3. Handbook, a l . : 8th Edition, 'Journal of ' L. C o l o m b i e r and J . H o c h n i a u n : R e s i s t i n g S t e e l s ' , p u b l i s h e d by 1965, p.109. vol. Metals', 75, Steel J r . and K . G . B r i c k n e r : Advances in S t a i n l e s s S t e e l s ' , ASTM-STP369 , 1965 , 62. 67. AIME, p.86. R. B l o w e r stitute' , et Institute', Reviews', 61. Gray p.!86t. of Stainp.l. Steel 'Metallurgical Progress', 1963, Transactions of Sept. p.433. 19, and 9, 1, p.419-422. Nov. 1978, D. P e c k n e r p.10-10. and ' S t a i n l e s s and Heat Edward A r n o l d Ltd., p.18. I.M. 82 68. W. H o l z g r u b e r : Proc. Pittsburgh, eds. G.K. 69. R.P. DeVries: Proc Pittsburgh, 1969. 70. H. F r e d r i k s s o n : 'Metallurgical N o v . 1942 , p. 2 9 8 9 . . 71. H. F r e d r i k s s o n and S e p t . 1971 , p.32. 72. R.O. J a c k s o n and and T e c h n o l o g y , 1 5th I n t e r n a t i o n a l S y m p o s i u m on E S R , Bhat and A. S i m k o v i t c h , 1 9 7 4 , p.70. 2nd 0. International Symposium Transactions', Jarleborg: Journal of on ESR, vol. 3, Metals, A. M i t c h e l l : ' J o u r n a l of Vacuum S c i e n c e V o l . 9, no. 6, Nov.-Dec. 1972, p.1301. 73. K . J . I r v i n e et al . : 'The M e t a l l u r g i c a l Evolution of S t a i n l e s s S t e e l s ' , ASM M e t a l s S c i e n c e S o u r c e B o o k , p.379. 74. W.T. vol. 75. ASM M e t a l s 76. ESR 4 3 4 0 77. B . E . Paton et a l . : on E S R ; , P i t t s b u r g h , 78. G.K. Bhat: Pittsburgh, Proc. 1971, 3rd I n t e r n a t i o n a l p.241. Symposium on ESR, 79. G.K. Bhat: Japan, June Proc. 1973, 4th International p.196. Symposium on ESR, 80. G. H o y l e : Institute, 81. B . E . Paton et Kiev, p.174. Pell-Walpole: 'Journal, 69, 1943, p.131. Handbook, steel data 9th from Institute Edition, Cabot Proc. 1969. 2nd 'Special 1, Metals', p.427-428. Corporation, Texas, International 'Electroslag Refining', London, 1973, p.136. a l . : vol. of Iron and 1977. Symposium Steel Electrometallurgy', 1972, 82a TABLES TA8i_E_I_ Rene'iting Log for Stainless Steel ESC Valves Valve No. 5 Valve Mo. 6 Valve No. 7 Valve No. 9 .Valve No. 10 Electrode Material CF-8M Rolled 316 Rolled 316 CF-8M Rolled 316 Electrode Diameter 3.5" (88.9 m m ) 3.0" (76.2 m m ). 3.0" (76.2 m m )3.5" (88.9 m m ) 3.0" (76.2 m m ) Slag Composition 702CaF/15%Al0/15%Ca0 70SCa/ F15%A!.„0,/15XCa070«CaF /l 5%A)i,/ 015XCaO70«CaF /15XAi 0 /"i 5SCa0702CaF /15ftU,u /153!CaO Slag Weight 6.8 kgs 6.8 kgs 6.6 kgs 6.8 kgs 6.8 kgs laegrageCondSietcioonndary Hot, dry, prefusedHot, dry, prefused.Hot, dry, prefused. Hot and dry Hot and dry ASv 3.72 KA 2.41 KA 3.50 KA 4.04 KA 3.71 KA Current Average Voltage 37.1V 38.0 V 38.0 V 33.4 V 37.0 V Average Melt RateC.942 kg/min 0.833 kg/min 0.868 kg/min 0.866 kg/min 0.888 kg/min 8 mins 101 mins 33 mins 117 mins 97 mins ToottalToMpaplitngTiCr.yecle8 H None 6.8 mins at 2.36. K 9 A mins at 2.16. K 1 A mins at 2.25KAmins at 2.2 KA Deoxidant A? powder Aa powder As. powder A2 powder Al powder Rate of Deoxidation1.2 grns/min 1.5 gms/min 1.6 gms/min 1.2 gms/min 1.3 gms/min Heltino Atmosphere Air Partial Argon Partial Argon Partial Argon PFaerCtri-a3l0;4Argo n g Al Joying Additions J None None Cr chips at 22.3 Ngo mn se /mir FeMo-<4.5 gm ms s/ /m mi in n 2 23 o 2 3 2 23 2 3 — CO OJ 84 -TABLE II Ferrite Valve No. 5 - Numbers CF-8M Ferrite As C a s t Location 10<F.N.<15 15<F.N.<20 15<F.N.<20 Top Centre Edge Valve No. - 6 - 316 Castings Magne-Gage Indicator Heat Treated 10<F.N.<15 7.5<F.N.<-10 10<F.N.< 15 (ii Ferri te Location As C a s t Top Centre Mid-Radius Edge 7 Steel As C a s t (F.N.)* Heat Treated 1.56 10.6 11.5 9.1 16.51 17.18 F e r r i t e No. Specimen No. Stainless (i) Specimen *F.N. of - 316 Specimen Location Top Centre Bottom Mid-Radius Edge ) Magne-Gage Indicator Heat Treated < F.N.<2 Everywhere + Cr F.N.<>2 Everywhere As C a s t (F.N.) Heat Treated 0.55 0.16 0.43 0.47 0.91 0.161 0.94 0.40 (iii) Ferrite As C a s t 2<F.N.<5 2<F.N.<5 5<F.N.<7.5 5<F.N.<7.5 5<F.N.<7.5 Indicator Heat Magne-Gage Treated F.N<2 5<F.N.<7.5 5<F.N.<7.5 5<F.N.<7.5 2<F.N.<5 As C a s t 3.34 5.56 4.31 4.72 5.68 (F.N.) Heat Treated 1.37 5.29 5.75 5.05 3.28 85 TABLE II Ferrite Valve No Numbers Ferrite As Conventional Castings Casting - Heat Cast Treated CF-8M As Ferrite Determined by 5.00 15.35 12.62 19.46 15.81 Magne-Gage ( F . N . ) Heat I r e a t e d Indicator Ireated 20.57 20.67 20.45 18.99 26.78 16.99 28.70 Numbers of Magne-Gage. Cast Stainless and Heat Steel Schoefer's Treated* Castings Diagram Schoefer's 16.85 10.80 16.8 (316) 0.65 0.35 <-!0 Valve No.7 - (316+Cr) 5.07 4.84 4.5 Valve No.9 - (CF-8M) 15.10 15.81 22 Conv.Cast (CF-8M) - 19.53 32 Valve No.5 - (CF-8M) Valve No.6 - - *From Magne-Gage Treated (v) As Casting Heat Cast 20'<F.N.<25 20<F.N.<25 20<F.N.<25 20<F.N.<25 F<N.<25 15<F.N.<20 20<F.N.<25 Top 3/4 Height Centre 1/4 H e i g h t Bottom Mid-Radius Edge (F.N.) 6.33 14.85 14.71 16.09 14.75 5£F.N<.<7.5 15<F.N.<20 10<F.N.<15 20<F.N.<25 15<F.N.<20 Ferrite Heat Specimen Location Average (Continued) Magne-Gage Indicator 5<F.N.<7.5 15<F.N.<20 15<F.N.<20 15<F.N.<20 15<F.N.<20 Top Centre Bottom Mid-Radius Edge Steel (iv) Location III Stainless CF-8M Specimen TABLE of Diagram 86 TABLE IV Interdentriti c Ratios Casting of Mi CF-8M Castings Segregation and Valve Conv. No. 5* Centre (CF-8M) No. 9* Edge Centre (CF-8M) Casting**(CF-8M) Edge Mi d - R a d i us Centre * in as-cast ** in solution-treated Ratio (C m a x / C min) Ni c k e l Molybdenum 1 .349 2 . 37 2.10 1 .25 1.18 2.19 2.48 1 .74 2.60 1 .167 1 .305 2.337 1 .625 2.178 2.587 3. 568 3.859 3.299 C h r o m i urn Pos i t i on Valve crosegregation condition condition 87 TABLE V Chemical.Composition of Valve No. 5 (CF-8M) (wt.SS) C Mn Si P S Ni Cr Cu Mo Nb Co Ti Zr Electrode 0.066 0.33 1.190.0270.01610.1920.31 0.44 2.51 0.0730.1080.0080.006 Top 0.086 0.34 1.060.0210.01010.0819.480.37 2.55 0.0C50.115 NA* NA* Centre 0.0630.26 0.740.0190.010 9.8019.86 0.15 2.53 - 0.0600.150 Side (L)0.055 0.25 0.730.0190.009 9.8819.39 0.16 2.55 - 0.0600.150 Side (R)0.056 0.26 0.730.2200.010 9.9119.720.16 2.58 0.0610.158 hi - - • - 11 II II II ••• II N.A. - not analysed TABLE VI Chemical Composition of Value No. 6 (316) '(wt'.*) C Mn Si Ni .Cr . CuMo-. . NbCo Ti Zr Electrode 0.049 1.89 0.670.0300.03111.6017.56 0.09 1.98 - 0.0620.4450.0080.006 Top 0.0721.89 0.640.0310.01111.9116.840.13 2.11 - 0.0610.278N.A.* N.A.* Centre 0.073 1.85 0.640.0300.01111.8016.89 0.12 2.09 - 0.0590.266 Bottom 0.075.1.840.640.0330.01111.6517.09 0.12 2.12 - 0.059'0.263 " Side (L) 0.069 1.84 0.630.0340.01111.4216.740.12 2.05 - 0.0610.258 0.650.0310.01111.8017.080.13 2.08 - 0.0600.283 Side.(R) 0.070. 1.86 , P s A£ II » II *N.A. - not analysed II 11 II II 88 TAG l E VII Chemical Composition of Valve No, 7 (316-tCr ) (w t. %) C tin Si P , SK i | CCur Ko . AN ib | CToi Zr Electrode 0.019 1.S9 0.670.0300.031 11.6017.. 56 0.09 1 .S3 0.0520.1950.0080.006 Top 0.074 1.87 0.610.0350.012 11 .11 88.91 0.12 2.01 0.0610.285 ( . ' . A . *N.A.* Centre 0.078 1.80 0.580.029-0.012 n.37'IS.93 O.o2 1.98 0.61 0.261 Bottom 0.072 1.79 0.5-50.0360.011 11.1319.25 0.12 2.00 0.60 0.256 Side (R) 0.062 1.81 0.570.0560.013 11.2619.880.12 2.01 0.61 0.290 - - - II - » - *N.A. - not analysed TABLE VIII Chemical Composition of Valve Ho. 9 (CF-8H) (wt.,%) C Hn Si P S Ni Cr Cu Mo At Nb Co Ti Zr Electrode 0.066 0.33 1.190.0270.01619.1920.31 0.11 2.51 0.0730.1080.0080.006Top 0.0580.35 1.010.0280.00910.3319.87 0.10 2.51 0.0680.0890.0130.005 "Centre 0.036 0.19 0.660.018 0.00910.1519.67 0.13 2.55 0.0600.1590.0050.001 Bottom 0.0370.27 0.670.021 0.009 9.7320.12 0.15 2.11 0.0630.1760.0050.006 Side (L)0.039 0.21 0.720.021 0.009 9.6320.51 0.13 2.19 0.0610.1850.0050.006 Side (R)0.011 0.20 0.700.0200.009 9.9020.19 0.13 2.51 C.0630.1930.0010.006 - - - - - - 89.. TABLE IX Chemical Composition of Valve No. 10 (316+Cr+Mo) C Mn Si P S Ni Cr Cu Mo At Nb Co Ti Zr Electrode 0.049 1.89 0.670.0300.031-11.6017.56 0.09 1.98 - 0.0620.4450.0080.004 Top 0.055 1.69 0.430.0300.01012.1018.470.10 2.32 0.0630.1020.0070.005 Centre 0.046 1.65 0.410.0270.01111.9119.140.07 2.32 - 0.0640.1340.0070.005 Bottom 0.051 1.62 0.280.0270.00912.1118.780.10 2.26 - 0.0640.1270.0070.005 Side (L)0.0481.65 0.400.0280.01111.9619.220.08 2.33 0.0650.1330.0070.005 Side (R)0.0401.61 0.390.0240.01011.9019.05 0.09 2.51 - 0.0650.1350.0070.006 {vit.%) - - TABLE X Chemical Composition of the Conventional Casting (CF-8M) (wt.SS) C Mn Si . PS Ni Cr Cu Mo An Nb Co Ti Zr Top- 0.029 0.61 1.240.0270.010 9.1319.41 0.25 2.02 - 0.0870.0670.0090.003 Centre 0.023 0.62 1.210.0260.010 8.9019.800.22 2.00 - 0.0860.0710.0090.003 Bottom 0.019 0.65 1.240.0310.010 9.3419.670.23 2.06 - 0.0890.0680.0080.003 Mid-radius0.0240.63 1.250.0290.010 9.0519.85 0.23 2.04 - 0.0870.0720.0080.003 Side (R)0.0200.63 1.240.0310.010 9.5719.36 0.23 2.10 - 0.0870.0660.0080.003 TABLE XI Percent c o m p o s i t i o n o f C r a n d Mo i n a r e a s and Parent the Valve No. XII Tensile C a s t i n g No. and Test D i r e c t i o n 1 54.88 12.56 Area 2 54.21 13.12. 22.10 1 .79 Properties of In Elonaation 1 i n c h ( 2 5 . 4 mm) % Valve Valve Nos. 5, 6 and 7 Yield Strength, 2% o f f s e t , Ksi(KPa) Ultimate Tensile Strength Ksi(MPa) 0 No. 5 (CF-8M) Lonaitudinal - 1 45 3 - 2 51 3 3 45 2 Transverse Valve Molybdenum (wt.%) Area Parent TABLE 10 C h r o m i urn (wt.%) Area Analysed 1 and 2 1 46 3 - 2 5 3'. 4 - 3 50 6 - 1 62 1 - 68 8 36 47 3 + (251.7) 35 8 ( 2 4 6 . 8 ) 38 6 ( 2 6 6 . 1 ) 77. 2 (532 ..3) 74 1 ( 5 1 0 . 9 ) 37 0 255 \ f 82 I 36 2 ( 2 4 9 . 6 ) 39 0 ( 2 6 8 . 9 ) 50 35 5 ( 2 4 4 , 8 ) (566.4) 77.8+ 536.4 71 7 ( 4 9 4 . 4 ) 36 9 254 4 1 75 3 ( 5 1 9 . 2 ) 70 7 ( 4 8 7 . 5 ) 72.6 + 500.6 No. 6 ( 3 1 6 ) Longitudinal Transverse - 2 71 1 ( 4 9 4 . 4 ) 34 1 ( 2 3 5 . 1 ) 64 8 + 31 1 ( 2 1 8 . 6 ) 3 63 6 31 1 ( 2 1 4 . 4 ) 1 69 6 32 3 ( 2 2 2 . 7 ) 2 62 4 3 64 1 65 4 + 34 0 (234.4) 31 2 ( 2 1 5 . 1 ) J. 32 5 ' 224 1 69 7 ( 4 8 0 . 6 ) 64 1 ( 4 4 2 . 0 ) 68. 3 470.9 + 68 0 ( 4 6 8 . 9 ) 32 5 224 + 1 69 4 ( 4 7 5 . 8 ) 70 6 ( 4 8 6 . 8 ) 69. 3 477.8 + Valve No. 7 (316+Cr) Longitudinal - 1 51 1 34 9 ( 2 4 0 . 6 ) J. _ •Transverse + Average 2 68.6 3 54 0 1 56 0 - 2 53 4 - 3 74 5 value. 57 9 ' 35. 2 ( 2 4 2 . 7 ) 33 9 ( 2 3 3 . 7 ) 73 6 ( 5 0 7 . 5 ) 34 7 239 3 + + 39 0 34 2 (268.9) (235.8) + 73 2 ( 5 0 4 . 7 ) ' 34 0 ( 2 3 4 . 4 ) 61 3 68 .4 ( 4 7 1 . 6 ) 71.7 494.4 66 3 ( 4 5 7 . 1 ) 35 7 246 2 + 75 3 ( 5 1 9 . 2 ) 70 7 ( 4 8 7 . 5 ) 70.8 488.2 + TABLE XIII Tensile Properties of Valve No. 9, Conventional Casting and ASME/ASTM Standards for AISI 316 and ACI CF-8H Elongation In 1 Inch (25.4 mm) X Reduction In Area, Casting No. and Test Direction % Ultimate Tensile Strength Ks1 (MPa) Yield Strength, 0.2% o f f s e t , Ks1 (MPa) .Valve No. 9 (CF-8M) Lonqltudlnal Transverse Edge - 1 80.0 - 2 82.0 70.7 - 1 82.4 70.0 - 2 78.7 73.0 71.3 Cl.O* - 3 77.9 70.5 - 1 79.4 73.7 - 2 82.0 80.7* . 69.0 71.0 f 71.2* 39.3 (271.0) 42.4 (292.3) 41.8 (288.2) 42.1 (290.3) 42.6 71.4 f (293.7) 44.2 (304.8) 42.8 (Z95.1) 82.4 40.9 282.0 + 42.4 291.0 + 82.3 + (567.5) 81.1 (559.2) 83.2 43.5 315070" (568.1) 82.1 (566.1) (573.7) 86.3 (595.0) 84.5 (582.6) 82.3 567.5 f 82.2 566.8 + 85.4 588.8 + t Average value. Conventional Cast (CF-8M) Lonqltudlnal* 0.25 2.50 Inches from the edge " » - • 74.3 46.6 57.0 (393.0) 82.5 (568.8) 72.6 52.0 45.0 (310.3) 82.0 (565.4) 4.25 " " " " 70.1 58.9 46.7 (322.0) 85.2 (587.5) 6.00 " " " " 62.0 53.Z 46.7 (322.0) 85.8 (591.6) 7.75 " " " " 63.4 56.7 45.9 (316.5) 84.6 (583.3) 1.90 Inches from the edge 3.75 ' Transverse* 5.60 " 72.2 58.3 46.4 (319.9) 84.5 (582.6) « . . 75.2 55.5 46.0 (317.2) 83.2 (573.7) " " " 65.7 55.3 46.6 (321.3) 84.7 (584.0) 30 (207) m1n 70 (483) min 30 (207) m1n 70 (483) m1n * Each value represents an average of 3 t e s t s . ASME SA-182 or ASTM A-18Z-77a(316) 50 (m1n) 30 (min)* ASME SA-351 or ASTM A-351 77(CF-8M) not s p e c i f i e d 30 (min)* r . * Elongation 1n 2 Inches (50.8 nm) 10 TABLE X I V . Tensile Properties of Large Specimens Reduction C a s t i n g No. and Test D i r e c t i o n from V a l v e Nos. 6 and 9 and S m a l l Elongation In 1 i n c h ( 2 5 . 4 mm) In A r e a , % % Specimens from a Large Specimen. Yield Strength 0.2% o f f s e t , K s i (MPa) Ultimate Tensile Strength K s i (MPa) 32.6 (224.8) 66.8 (460.6) 29.0 (200.0) 61.8 (426.1) 31.0 (213.7) 62.6 (431.6) 36.2 (249.6) 73.0 (503.3) 37.1 (255.8) 38.7 (266.8) 38.4 (264.8) 37.0 (255.1) V a l v e No. 6 ( 3 1 6 ) Longitudinal V a l v e No. 9 No. 9 (From l a r g e 78.8 - 2 82.0 - 3 83.0 - 1 85.2 - 80.7 2 69.3 f 66.0 57.8 30.9+ 2 1 3 - \ 1 63.7+ 4 3 9 - 2 47.9 83.0 47.5 + 47.7 + 36.7+ 2 5 3 - 0 74.0 (510.2) 73.5+ 5 0 6 - 8 -1 - 1 87.0 Edge - 2 87.1 t Average 81.3 + (CF-8M) Longitudinal Edge Centre 70.9 (CF-8M) Longitudinal Valve - 1 - 1 value. 24.2 • 86 35.8 73.1 84.5 71.1 + 78.2 38.0+ 2 6 2 -° (539.2) 73.0 (503.3) 73.7 (508.2) 75.0+ 5 1 7 - 1 TABLE XV Remelting Log for AISI 4340 Steel ESC Valves Valve No. 3 Valve No. 8 Valve No. 11 Valve No. 12 Valve No. 13. Valve No. 14 MEalteecrtirao"d!e Rolled 4340 Rolled 4340 Rolled 4340 Soiled 4340 Rolled 4340 Rolled 4340 EDlieacmtertoedre 3.25" (82.6 m m )3.25" (82.6 m m )3.25" (82.6 m m )3.25" (82.6 m m )3.25" (82.6 m m ) 3.25" (82.6 m m ) 4 6 X C a F 2 / m A t 0 / 4 6 2 C a F / 1 7 3 ! A i 0 / 4 6 % C a F / 1 7 2 A t 0 / 4 6 % C a F / 1 7 « A t 0 / 4 6 % C a F / 1 7 » 0 / 1.75%CaF/26.5%M0/17%Ca0/20%La0 17%Ca0/20%La0 17SSCa0/202La Slag 6 0 mCaO/20XLa0 173XaO/20XLa0 11.75%Ca0 Soe lmaipggohstition9.1 kg CW 6.8 kg 6.8 kg 6.8 kg 6.8 kg 6.8 kg Slag Liquid CaF„, Hot and Dry Hot and Dry Hot and Dry .Hot and Dry Hot and Dry A v e rin atdgiaeorny H 3.72 KA 3.59 KA 3.60 KA 3.55 KA 3.60 KA .t 73AK S e c o C o n d «A0 and CaO | Current 2o j1AvVeorlatgaege'36.9 V 37.1 V 36.9 V 36.8 V 35.4 V 36.0 V A Mv eelrtageRate1.022 kg/min 0.938 kg/mins .0.967 kg/min 0.854 kg/min 0.785 kg/min 0.812 kg/min TMoetlatl Time87 mins 98 mins 98 mins • 112 mins 113 mins 110 mins H 7.2KAmins at 2.2 6.7-KAmins at 2.2 8.3KAmins at 2.2 6.7KAmins- at 2. 92 .2KA mins at 2.3 KA . Co yctleTopping3.2 mins at 2.6 Deoxidant At powder At powder At powder At powder At powder At powder R Oeaotxeidatoifon2.4 gms/min 1.2 gms/min 1.2 gms/min 1.2 gms/min 1.4 gms/min 1.4 gms/min Partial Argon Partial Argon' Partial Argon Air Air |MAetlmtoisnpghere Air 2 23 2 23 23 2 23 23 23 23 2 23 23 2 23 23 23 OJ 94 TABLE XVI Interdendritic AISI 4340 ESC Microsegregation No. the Centre Valves Segregation V a l ve at Ratfo (C ma x / C min) Chromium Nickel Molybdenum Valve No. 3* 1 .39 1.13 2.15 Valve No. 8* 1 .34 1.14 2.21 Valve No. 13** 1.12 1 .60 1 .24 1 .30 1 .05 (At mid-radius) Valve No. 14** *In as-cast **The whole condition valve was heat-treated. of TABLE XVII Chemical Composition of Valve No. 3 (4340) (wt.%) C Mn Si P S Ni Cr Cu Mo An Nb Co V B W Ti Zr Electrode0.42 0.770.370.0210.015 1.870.80 0.100.21 0.0130.0530.0290.0120.00060.0180.0110.003 Top 0.42 0.780.410.0210.0041.84 0.83 0.07 0.220.0950.0240.0330.0170.00140.026N.A.N.A. 00 .0190.0041.800.81 0.080.21 0.0820.0230.0310.0160.00110.026 Centre 0.40 0.76' 0.4 Bottom 0.40 0.73 0.370.0180.0041.79 0.80 0.080.21 0.1270.0200.0280.0160.00130.024, Side (L)0.40 0.75 0.380.0180.0031.81 0.81 0.080.21 0.0850.0H0.0280.0160.00090.022 Side (R)0.42 0.78 0.400.0190.003 1.830.82 0.080.220.0730.02;0.0310.016'0.00100.024 II " II « •• i *N.A. - not analysed CO TABLE XV11I Chemical Composition of Valve No. 8 (4340) (wt.%) C Mn Si P S Ni Cr Cu Mo Nb Co V B w Ti Zr Electrode 0.42 0.77 0.370.0210.015 1.87 0.80 0.100.210.031 0.0530.0290.0120.00060.018 0.011 0.003 Top 0.43 0.800.330.0300.004 1.90 0.81 0.11 0.220.0350.0560.0420.0130.00070.024 0.0050.004 Centre 0.41 0.77 0.340.0280.004 1.86 0.800.11 0.220.0480.0560.0390.0120.00070.023 0.0050.004 Bottom 0.40 0.75 0.200.29 0.003 1.74 0.76 0..100.210.051 0.0520.0300.0120.00050.016 0.0040.003 Side (L)0.41 0.75 0.340.29 0.003 1.80 0.78 0.100.210.0430.0530.0320.0120.00070.016 0.0050.004 1.79 0.340.280.002 1.87 0.81 0.11 0.220.0450.0510.0240.0120.00060.019 0.0040.003 Side (R)0 '.-40 M LO CXl TABLE XIX Chemical Composition of Valve No. 13 (1310) (wt.%) C Mn Si P S Ni Cr Cu Mo At Nb Co V B W Ti Zr Electrode0.42 0.77 0.370.0210.015•1.870.80 0.100.210.031 0.0530.0290.0120.006 0.018 0.0110.003 Top 0.43 0.84 0.180.0300.003 1.89 0.86 0.31 0.210.0200.0530.0550.0110.00040.041 0.0030.002 Centre 0.420.86 0.110.0300.001 1.880.86 0.3o 0.210.021 0.0530.0570.0110.00040.044 0.0020.002 Bottom 0.420.76 0.040.0300.001 1.790.83 0.300.210.0170.0520.0590.0100.00040.039 0.0030.003 Side (L)0.40 0.80 0.090.0290.0021.750.82 0.31 0.200.021 0.0520.0620.0110.00040.033 0.0040.003 Side (R)0.41 0.82 0.100.0300.0021.800.84 0.31 0.210.0220.0550.0650.0110.00040.037 0.0040.003 • TABLE XX Chemical Composition of Valve No. 1 4 (4340) (wf.%) C Mn Si P S Ni Cr Cu Mo At Nb Co, V B w Ti Zr Electrode0.42 0.77 0.370.0210.015 1.870.84 0.10 0.210.031 0.0530.0290.0120.00060.018 0.011 0.003 Top 0.44 0.84 0.190.0330.0041.900.86 0.31 0.210.018 0.0580.0710.0120.00060.050 0.0030.004 Centre 0.45 0.88 0.140.0320.0021.980.880.30 0.220.022 0.0570.0660.0120.00060.056 0.001 0.003 Bottom 0.46 0.87 0.050.0330.0022.039.900.30 0.220.013 0.0590.0720.0120.00050.064 0.001 0.004 Side (L)0.45 0.89 0.090.0330.0021.94 0.870.31 0.220.018 0.0590.0880.0130.00060.050 0.0030.004 Side (R)0.45 0.89 0.090.0320.0021.970.880.30 0.220.016 0.0600.0900.0120.00060.055 0.001 0.004 to 98 TABLE XXI Sulphur Contents of AISI 4340 Electrode and ESC Valves Electrode Valve No. 3Valve No. 8 Valve No. 13Valve No. 14 SCuolnptheunrt 0.0146 0.0040 0.0037 0.0055 0.0053 (wt.%) TABLE XXII Dimensional Measurements on V a l v e N o s . 11, 12 and 13 and L o c a t i o n f e 9 h 1.97 3.09 2.55 4.55 1.48 4.34 1.67 4.17 1.92 4.12 1 .29 2.70 2.34 3.26 0.47 1.73 0.97 2.22 1.27 2.52 1.61 2.87 2.36 4.22 2.27 3.30 . 2.18 3.36 2.23 3.30 2.19 3.37 2.99 4.17 % Shrinkage d c V a l ve No. Shrinkage Type a b Valve No.11 Real Pseudo 2.37 3.60 2.68 4.10 2.33 3.75 1.35 3.05 Valve No.12 Real Pseudo 1.87 3.36 1.07 2.31 1.72 2.80 Valve No. 13 Real Pseudo 2.43 4.64 2.01 4.26 2.53 4.25 ; i TACBaL E XXN Io I. I Tan ednsile Properties of AISEIlonga4t3i4 0 EInlectrYoiselladgStCraensgtthValveUsltimate Tensile o n s t i n g Reduction 1n Area,1 inch (25.4 mm Test Direction 0) et, SKtsirengt(hMPa) K., s2i% (oMfPfas) % Valve No. 3 (a) 1 8 5 . 1 ( 1 2 7 6 . 3 1 7 4 . 6 ( 1 1 9 72..01)) 17 17 0. 1 8 . 0 Longitudinal - 4 1 8 7 . 8 ( 1 2 9 2 . 8187.0 + 1 7 6 . 8 ( 1 2 1 6 . 2 + . 2 3 3 . 3 1 8 8 . 0 ( 1 2 9 6 . 3 1 7 9 . 1 ( 1 2 3 4 . 9 ) ' 8 . 6 + 8.5 30.1 37.1 1 289.4 1 8 4 . 1 ( 1 2 6 9 . 4 1 7 4 . 0 ( 1 1 9 9 1 7 ) 9 . 3 3 3 . 9 1 8 3 . 8 + 1 8 4 . 7 ( 1 2 7 3 . 5 1 72 1. .9 8 ((11118874. .3 6) ) 17 2 . 7 + 18 1. .2 3 7 . 8 Transverse 1 2 6 7 . 3 1 8 2 . 7 ( 1 2 5 9 . 7 1 7 9 . 1 + 4 36.4 36.0 Valve No. 8 (b) 1 4 9 . 9 ( 1 0 3 3 . 6 ) 14 64 4. .3 7 (11113320..88164.7+ 1 6 . 5 42 6. .2 0 Longitudinal - 4 1 4 9 . 3 ( 1 0 2 9 . 4 ) 1 0 0 6 ( 1 4 . 7 17.9 16.4+ 150.7 (1039.1) '165.1 (1138.14135.6 47.7 45.3 1 6 6 . 3 ((11114562..58166.4' 1 5 1 . 8 (1 10 05 44 6. .9 7) ) 1 5 . 5 4 1 .2 8 1 6 7 . 2 1 5 3 . 0 ( 1 7 . 0 4 4 . Transverse 65.8 (1143.12147.3 1)52. 1 $ 44.7 43.6 17.816.8 152.6 (1052.2 1 6 0 . 4 (11113096..10162.8 1 4 9 . 1 ( 1 0 2 8 . 0 ) 1 4 . 1 51.3 1 6 5 . 2 ( 150.5 (1037.7) 17.5 46.1 Edge 1122.5 1 4 9 . 8 1 5 . 8 4 8 . 7 ValLovnegituNdo 1032.9142.1(979.8 ( 8 2 8 . 1 ) 3 . 7 7. 1 1 2 0 . 1 i. nal 13- (c) 9 12 280..11 V 1 3 9 . 2 (828.1)8 4 . 2 ( 9 5 7 . 0 3 8 . 8 . 4 1 2 0 . 1 9 5 9 . 10.9 9.1' 5.8 4.6 + 120.1 (828.1) 136.6(941.9 8 ( 9 2 4 . 6 1 3 4 . 1 3 . 5 18 1. .7 13 35 . 4 + ( 9 3 3 . 62 9 1 3 5 . 4 1 2 2 . 4 ( 8 4 3 . 9 ) 4 . 9 7 Transverse 3 . 6 1 2 0 . t f ( 9 4 3 . 1 3 6 . 8 2 0 . 1 ( 8 2 8 . ) 9.4 9.9 + 4.5 4.3 + 1 8 3 1 2 0 . 1 ( 8 2 8 . 1 )3.6 ValLovnegituNdo . 1 3 ( d ) 1 509.. 6 1 4 7 . 7 ( 1 0 1 8 . 4 ) 1 6 . 7 32 9. 9 inal - 4 1 1 0 4 1 4 7 . 5 + 1 5 9 . 8 ( 1 1 0 1 . 8 4 7 . 3 ( 1 0 1 5 . 6 ) 8 . 5 17.6 1 .9 0 41.0 1 1 5 6 . 6 + 1 4 6 . 2 ( 1 0 0 8 . 0 ) 1 7 . 0 3 2 . 1 0 7 9 . 8 5.2 144.3 (994.1 0) 11 7. .80| ( . 31.7to32a.3hardness13o.f31 ee rm speered at 482°C 19 0 0 ((baTj)ransvTT 3 8 R c . 5.3+1 157.9 (1088.7 eh me peredwholaet v5 5 0 ° Cwa ts o aheath-atrredanteesds aonfd 3t5emperRecd. at 560°C. Aver1a4g 1a5r5dh .na3ersdsne(s1s0o7f0.o8fthe33tenRsc ((dc)) T a l v e eah il.e specimens was 31 Rc. T h e s p e c i m e n b a r s w e r e r e h e a t t r e a t e d a n d t e m p e r e d a t 5 6 0 ° C t o t Average value. 1 1214 9 T 1190,8 T 1034 1 1 T 3 105K5 T T T T T T 15g3 1098 4 CD CD TABLE XXIV Tensile Properties of CoEnlovnegnattiioonnalInAISIYie4 340StrenHgotth aRtolleLdoUwletriBmaarte Tensile l d S PoPian)t SKtsirengt(hMPa) m )YKiseild(M Tp ee sc timenDirecNto i. on and Reduction In Area,1 inch (25.4 m 1 64 2. .3 8( (1 11 13 22 2. .8 5) ) 163.6" 1 5 0 . 7 ( 1 0 3 9 . 1 ) 1 9 . 2 7 . 7 Lonqitudinal--21 5 1 6 15 0 . 0 ( 1 0 3 4 . 3 ) 1501. 8.6 (1128.0)'° 9 . 5 57 8. .5 2 57.8 1 6 3 5 1 . 8 ( 1 0 4 6 . 7 ) ' 19 6. .4 2 18.3 1 -3 5 1 61 2. .1 0( 1 1 1 7 . 0 ) 1 5 0. .1 3( 1 0 3 6 . 3 ) 1 . 9 Transverse --21 2 1 6 ( 1 1 1 0 . 8 ) 162.0 1 4 9 ( 1 0 2 8 . 0 ) 1 5 0 . 2 9 . 5 9 J S 2 2 , 7 2 2 . 7 1 6 2 . 8 ( 1 1 2 2 . 5 ) -° 1 5 1 . 3 ( 1 0 4 3 . 2 ) 10.5 - 3 23.5 (a) Tempered at 560°C to a hardness of 33.5 Rc' Diameter of the bar was 3.25 inches (82.6 m m ) t Average value. TABLE XXV Transverse Tensile PropertEileosngatoiofn AiIrn Melt,edYieladndStrV agctuhum ATrecnsileMeltSterdengt4 340 Steels e n h R e d u c t i o n T in Area, 2 inches (50.8 mm),Ksi (MPa) Ksi (MPa) Te em mp peerriantgure Air Melted 480°C 149 8.0 173 (1192.8) 200 (1379) 540°C 220 10.0 163 (1123.9) 180 (1241.1) Vacuum Arc Remelted 480°C 200 9.0 175 (1206.6) 200 (1379) 5 4 0 ° C 2 4 0 1 0 . 5 *werPeropenrottiesavlaiisltaebdle.are averages of several heats from the160same(110p3r.o2d)ucer;180 billet(12s4i1z.e1)and amount of hot redi TABLE XXVI Lonqitudinal Mechanical PropertiesYieldofStrBeanrgthSTteoncskileMa d e From Ree melted 4340 Steel H a r d n s s S t r e n g t h Melting Method Reduction In AreEal,ongation In 4D.Ksi (MPa) Ksi (MPa) (MRc) 3 7 1 71 5( 1 2 0 6 . 6 ) 1 6 3 ( 1 1 2 3 . 9 ) 1 6 . 4 6 1 . 2 V A R < > 3 7 1 7 ( 1 1 7 9 . 0 ) 158 (1089.4) 16.1 59.0 ESR< > (a)AllBarsspeciw e rs e tnaokremnalisefdromatmid9 0 0d°iCu,s. oil quenched from 845°C, and tempered 2 hrs. at 541°C. m e n r a (b) 3.62 inch round. (c) 4.625 inch round. % % b C % 1039 8 1035 6 % 1,28 + + + f 1 + f + lll7 TABLE XXVII Mechanical Properties of ESR 4340 Material in the Transverse Direction HeatTreated to Different Strength Levels.* ra en)gth la d)StrengthTensKisile (SMtP T Reduction in Area, Elongation 0.K2s*i Y(iMeP Te em mp pe er ri antgure 8 0 . 6 ( 1 2 4 5 . 28)) 1 68 9. .3 4 ((11019618..50)) 1 1 2 . 9 4 5 . 1 5 3 8 ° C 1 7 3 . 0 ( 1 1 9 2 . 1 5 1 4 . 6 4 9 . 2 566°C * Data from Cabot Corporation. Notes (1d)iametTeernsilteransdvaetrasewe r e gteankeernatedfromfroma.a24-0i.n3.57diaimne.ter(9mm ) diinagmoetterforgteedstfears matcohined f.romdihaemaett-etrr.eated 1-in. b a r s E S R 3 : 1 1 4 i n (2)(83All 0°C)sampalneds twee mr pe erednoramtalisvedariouast t1e75 m0 p° eF ratur( e9 s5 .4°C) prior to heat-treating, then austenitized at 1525°F (3) Tensile values are average of five tests. Xo X. VIIan1d (a) RedTuecntisoinleInProApreerat,iesElonogfationLargIen SpecYiimeledn Stfrreonmgth,ESC UVltailmvaete ToefnsilAeISI 4340 Steel. CTTaeA ssB ttiLnEgDirN tM hP ,a) 0 2i% (oMfPfa s) et, SKstireng( 3 inches (76.2 m m ection K.s) VaLlovnegituNdo * 1 48.1. 47.9 160 17)) 1. 46 5.5'( 1 .5 7 18.1' 1 i. nal-8. 3 (1 11 10 07 5. .3 3) ) -160.5+ 14 44 6. .9 0 ((1909096.. - 160 19 6. 2 47.6 * TA ev mp + ee rr ae gd e avtalue5 .50°C to a hardness of 34.5 Rc. XXVITTIM Tensile Properties of Small Specimens Cut From Large Tensile Specimens Ym ie. l2d%Storfefnsgetth,, UltSimtarteengthT,ensile S 0 ) Tp ee sc timenDirecNto i. on and Reduction%In Area,1Elongiantcihon(2I5n.4 m Ksi (MPa) Ksi (MPa) Value No. 8 (LFr oo nEmgdigteudLianragle--1) 164.8 (1136.3) 1 4 9 . 7 (( 19 09 37 2. .7 2) 4 5 .6 2 46.5 16.7 1 1 4 4 . 7 ) 1 4 6 .3' 4 8 . E d g e 2 1 7 . 4 1 7 . 4 1 4 4 . 5 ( 9 9 6 . 3 ) ' 4 5 . 7 159.7 (11011 .1 11 )? 9 161.4 + Centre r 1 18.0 159.7 (1101.1) " + Average value. 67 % - % % % 1 1 1 1003 2 1008 7 1106 6 TARIF % f 1 1 U o 102 TABLE XXIX FATT Values Estimated Transition Characteristics Valves Electrode, Type Valve and and O r i e n t a t i o n Specimen No. 3 Electrode Notes: (1) (2) (3) (4) (5) from of -- Long. - Long. Trans. •- Long. . T r a n s . (T) T r a n s . (L) Edge Valve No. 8 Valve No. 1 3 -- Long. Trans. Ductile of Brittle AISI- 4340 ESC Est i mated FATT -40°C 5°C 45°C -25°C -30°C -35°C -32°C 20°C 20°C The FATT v a l u e s h a v e b e e n e s t i m a t e d according t o a s u g g e s t e d m e t h o d i n ASTM E 2 3 - 7 2 . FATT has been d e t e r m i n e d as t h e temperature c o r r e s p o n d i n g t o t h e e n e r g y v a l u e 50% o f the d i f f e r e n c e b e t w e e n v a l u e s o b t a i n e d a t 100% a n d 0% f i b r o u s fracture. T h e s p e c i m e n s h a v e b e e n a s s u m e d t o be 100% f i b r o u s a t 1 0 0 ° C a n d 0% f i b r o u s at -100°C. The l a t t e r i s n o t e x a c t l y t r u e as some a r e a s w e r e f o u n d t o be d u c t i l e e v e n a t -100°C. T h e h i g h FATT f o r V a l v e N o . 13 i s p r o b a b l y d u e the inadequate heat treatment. These a r e j u s t e s t i m a t e d v a l u e s and not exact because of the kind of f r a c t u r e d s u r f a c e (as mentioned in the text). to 100a FIGURES \ (d) Figure 1 . Electroslag Cast Products. (a) Valve Bodies; (d) Crankshaft (b) with pin 8 Rolls; diameter (c) of Dentures 480 mm. 104 1 straight tube, 2 source material, 3 ringtype mould, 4 molten-slag bath, 5 moltenmetal pool, 6 slag film, 7 start piece, 8 feed roller for source material, 9 drawing apparatus, 10 electric power source, 11 cooling water Figure 2. 'Y0Z0' process products p i pe , of Mitsubishi 11 12 tube. ' Heavy Industries Ltd: ELECTRODE ^ . „ „ „ . i , SLAG POOL METAL POOL SOLIDIFIED POWER SUPPLY TRANSFORMER or RECTIFIER SLAG CASTING SKIN COOLING WATER CRUCIBLE BASE PLATE X Figure 3. Schematic of the ESC p r o c e s s o Figure 4. Fracture toughness containing varying of ESC A I S I amounts of 4340 steel sulphur. 2 Figure 5. Electroslag casting installation at U.B.C. 108 Figure 6. Orthogonal views of ESC v a l v e body. 109 Figure 7(a). Plan views of the valve mold segments. 110 Section A-A Section Figure 7(b). Sections through A'-A 1 the v a l v e mold segments. Figure 9. Slag melting furnace. Figure 10. Solidified slag skin on the casting. 113 Figure 12. Stainless steel ESC valve. 115 Figure 13. Longitudinal to moisture. holes in the castings due Figure 14. Schematic the of valves. the sectioning procedure of Figure 15. Macrostructure of Valve No. 5 (CF-8M) Figure 16. Macrostructure of Valve No. 6 (316). 118 Figure 17. Macrostructure of Valve No. 9 (CF-8M). Figure 18. Macrostructure (316+Cr+Mo). of Valve No. 10 120 Figure 19. Macrostructure (CF-8M). of conventional casting 640 Figure 20(a). x Microstructure of heat (etchant treatment CF-8M ESC v a l v e s - oxalic before acid). 122 640 Figure 20(b). x Microstructure of heat (etchant treatment CF-8M ESC v a l v e s - oxalic after acid). 210 Figure x 540 21. Microstructure (etchant of - oxalic as-cast x ESC V a l v e N o s . 5 , x 6 and 7 acid). Top Row - V a l v e N o . 5 ( C F - 8 M ) , M i d d l e B o t t o m Row - 1100 V a l v e No. 7 (316+Cr). Row - V a l v e N o . 6 (316), 124 210 Figure x 540 22. Microstructure of (echant - o x a l i c Top Row - x 1100 h e a t - t r e a t e d ESC V a l v e N o s . 5 , x 6 and 7 acid). V a l v e No. 5 ( C F - 8 M ) , M i d d l e B o t t o m Row - V a l v e N o . 7 (316+Cr). Row - Valve No. 6 (316) 125 640 Figure 23. x 1300 Microstructure of 850°C - (etchant light dark black grey grey area CF-8M specimen heated KOH). area area - austenite phase ferrite phase sigma phase x to Figure 24. Microstructure conventional of heat-treated casting (etchant CF-8M - KOH). 127 Figure 25. Microstructure of cast (etchant condition Valve No. - 9 in KOH). as- 128 Figure 26. Microstructure treated of condition Valve No. (etchant 9 - in heat- KOH). 700 Figure 27. Microhardness and austenite x indentations phases. on sigma Figure 28. Schoefer's ferrite diagram numbers of for determination stainless steel of castings. Figure 29(a). Variation of C r , Ni and Mo a c r o s s direction in V a l v e No. 9 a t the the edge. dendritic 132 • TRAVEL t F i g u r e 29(b) V a r i a t i o n of direction 1-0 mm H C r , N i and Mo a c r o s s t h e i n V a l v e No. 9 a t the dendritic centre. 135 • TRAVEL i 10 mm. direction in conventional 1 c a s t i n g at the centre O.II6| 0.066 0.016 2.65 2.55 2.45 10.41 9.91 9.41 20.04 19.54 19.04 • —© w —8— —9 6 O 8 9 • • • • • 0 0 o o O • • • o o 10 —A II .7 o o 0 12 13 14 C 0 —0— Mo Ni Cr o- 15 195 mm. I 2 3 E 4 in e / 8 10 Microprobe 12 13 14 15 _i_ ^ ^1" O IT) O oicrib — ^. °! ^. o^°^Q _i_ iDiOuD ifilD cJcvJcvj _i_ — lO — ri ° CM Figure 31. Composition variation (The s o l i d line i n V a l v e No. 5 shows t h e o v e r a l l (CF-8M). average composition.) °. OO • • • • • 9 • • • • • • o o o —o o o o O o • • • • 0 0 10 II 12 o • • # W o o o 16 3 17 0 o o 13 14 15 u o • • o 18 o o 19 20 m \j W U 21 • o - 0.089 • 0.069 0.049 o 2.13 2.08 2.03 • 12.19 11.69 11.19 o o - 1732 16.82 - 16.32 22 23 ^ & 0 0 roCOrO 295 mm- ^> ^ t: CD ^ 0 1 m rOCOro <X> 22 r= ™ Q C2 c\i oj 12 13 14 15 Figure 32. 16 17 18 19 20 21 Composition variation (The s o l i d line 22 23 0 i n Valve No. 6 (316) shows t h e o v e r a l l average O Q Q <\i o d d o 10 cn <r> cr> srtoco composition.) 138 0.094 0.069 o 0.044 2.05 ZOO 1.95 _• 11.86 11.36 10.86 19.62 19.12 18.62 • 4 o o o o • • * u CJ • II o • • 12 13 o o • c 6 • Mo Ni o o • • 14 15 • 16 • Cr 17 -155 mm. 12 13 14 Cr 16 Mo Ni C 17 e £ m O CVJ 8 8 9 9 10 10 C\JC\JC\I co ID co L Q C ; in CO CD COrOOO CT) CJ O _ crjcricT) Figure 33. Composition v a r i a t i o n (The s o l i d line i n V a l v e No. 7 shows t h e o v e r a l l o — — — ^ ^ (316+Cr). average composition.) "tf cn <3<X> <X> ooo boo 139 0-061 0041 0021 - 263 o o o 2-51 6 o o 0 o o ^ n n 0 —O— v Mo 239 10-49 9-99 949 20-48 19 98 19-48 Ni • • • ° o n - 0 o o Cr o I9|2C|2I |22|23|24|25ll0|26 27 28 29 30|3I 32 Cr -295 mm. 1 2 3 4 5 6 7 e microprobe j2\|22|23l24|25 10 26|27|28|29l30|3l|32 E E in N ro 9 10 11 Mo Ni o • > 0 • o m 0 o o o < 0 0 o o 0 o ( 0 Composition v a r i a t i o n (The s o l i d line • • • a 0 14 o > o 15 3 • 16 0 • 0 o 0 • I - i n V a l v e No. 9 shows t h e o v e r a l l • 0 . ? oo oo oo cn cn cn ^- cn ? t cn if £ ch w o ch cn o Figure 34. 0 o t i 1 ft X o do o oo (CF-8M). average • • • 0 12 13 17 18 • • • • • • composition.) 140 0-059 0O49 0-039 - • • • o • • - 289 239 o I- 89 12-56 12-06 II- 56 - 1940 18-90 18-40 - o u • • • • 15 n o -o "D 0 0 o 0 -A W w O O u • • • • o o • Q 0 • o u Mo NI Cr o o 1-6 17 18 19 6 20 21 22 23 24 IQR Cr mrr 1 15 16 17 18 19 20 21 22 23 24 E 6 ID o 4 c 5 < 6 o • • 7 o « 8 o 10 o 0 II 1 1 12 13 13 ) 14 0 1 1 OOO Composition v a r i a t i o n (The s o l i d l i n e c i n V a l v e N o . 10 shows t h e o v e r a l l » c • (» 0 1) c « o t o * cb cb Figure 35. » c 12 14 • o • • • • • <> o 9 10 Mo • o 2 3 NI c ( c • • • • c < 0 < o • 0 1 * 1 <£<0<£ "Opip 1< 1 • 1 ©0105 cbroeo — — OJ 1 »1 ( men g> oo o 66 6 (316+Cr+Mo). average composition.) 141 • •• 0027 0022 0 017 O 208 203 O 1-98 o " . u.. ... o 9-65 9-15 8€5 Q O O o o ° o Mo • •• 2019 19-69 1919 o Ni o o o o Cr 17 18 19 2 0 2 1 22 23 2 4 25 26 27 Cr 230mm.- Ni Mo 1 •I 2 o 3 O 4 o 5 6 micro probe o o 8 17 18 19 20 21 2 2 23 2 4 25 2 6 27 9 10 o 10 o 0 II 12 12 o 13 13 o 14 14 o 15 15 16 16 Figure;36. o o 7 • o o Composition v a r i a t i o n (The s o l i d line _l_ _L L S — 58 <p C® NQQ 5ch cb cn ch — CVICVJ in conventional shows t h e o v e r a l l _i_ —$ — o to casting. average composition.) r-CJ r SOU CCO O O 6 Figure 37. SEM p h o t o g r a p h s of alloy area powder in agglomerated 1 in Valve ferro No. 10. Figure 38. SEM p h o t o g r a p h s of alloy area powder in agglomerated 2 in Valve ferro No. 10. hi • t' »• # » r ; : ..* . • J Parent Metal .'I . * • 1 Area I to •E 3 o o o Area 2 • •• • t. •• • • * • • /K Mo /f\ /K /N /N /K Cr Cr Fe Fe Ni 39. EDXA p l o t s the of ( V a l v e No. • • • • Ni agglomerated f e r r o parent metal • • • • 10). • • •• • • • • • • • • #M» • • • • • • • • • * • • ••• • M • • « • • • • • • A - • • *• • • • • • • • »»W . . Mo X-ray Figure •» • • alloy Energy (K eV) powder i n a r e a s 1 a n d 2 and 4^ Areas 18 2 o u Fe-Cr Powder o ** /N / K /N /N Mg Al Si S • • : A • Co X-ray Ca Ti Cr Mn Fe Fe Energy (KeV) cn F i g u r e 40 ( a ) . EDXA p l o t s o f i n c l u s i o n s i n a r e a s 1 and 2 and F e - C r - p o w d e r . Areas I 8 2 • -.v V*.- (A C 3 O o o Fe-Cr v..V.- Powder ••„.••.•. ^ * ^ ^ ^ Mg Al Si Ca Co X-ray Ti Energy /K /ts. /*> Cr Mn Fe • * *M • A • Fe (KeV) CD Figure 40(b). EDXA p l o t s o f i n c l u s i o n s in areas 1 a n d 2 and F e - C r powder. S S Co X-ray Figure 40(c). EDXA p l o t s Co. Energy of Fe (KeV) inclusions in Fe-Mo powder. Figure 41. Macroporosity CF-8M in electrode. the Centre of the 149 Figure 43. M a c r o s t r u c t u r e of the CF-8M electrode. (5.5 x) 150 Figure 44. Inclusions Valve No. graphs). in 9 the and electrode electrode piece tip dropped (optical in photo- Electrode Piece Electrode Tip 2000 x 950 x P a r e n t C a s t i n g 4000 x Figure 45. Electrode P i e c e 4000 Electrode Tip x 1900 x P a r e n t C a s t i n g 8000 I n c l u s i o n s i n t h e e l e c t r o d e p i e c e dropped i n V a l v e No. e l e c t r o d e t i p and t h e p a r e n t c a s t i n g ( V a l v e N o . 9 ) . 9, x Electrode Piece » .* • • *V* •••••• *.* •»... v. c o o Electrode Tip o . .. . * 4s Al A ^ Si P Ti X-ray Energy Cr Mn Fe Fe Ni (KeV) ro Figure 46(a). EDXA p l o t s o f i n c l u s i o n s i n the e l e c t r o d e p i e c e dropped i n Valve No. 9 and t h e e l e c t r o d e t i p . 1 M P tt 4\ S Co X-ray Ti Cr ^ Mn Cr Fe 4* 4> Fe Ni Energy (K eV) co Figure 46(b). EDXA p l o t s o f i n c l u s i o n s i n the parent c a s t i n g (Valve No. 9), 154 Figure 47. Schematic to e x p l a i n V a l v e No. 9 . the peculiar pool p r o f i l e observed in 155 ure 48. Macrostructure observed in of the peculiar Valve No. 9. (5.5X) pool profile 156 I I I Large Specimen (316 a n d C F - 8 M ) Small Specimen (316..CF-8M and 4340) 1.00 inches 0.75 inches D 0.25 6 1.00 " 4.00 " 3.00 " A 1.25 " 5.00 " 3.75 " R 3/16 " 3/4 9/16 " T 3/8 2 2 Figure 49. inches Large Specimen (4340 Schematic of the t e n s i l e specimens used. 600 80h 500 70 £ 60 400 o a. ca 50 3 UJ 300 S| or 40 CO i 200 30 ca UJ or »CO 20 O Tensile Strength • Yield Strength A Elongation 100 10 8 10 _L 12 FERRITE Figure .50. Variation steel of tensile castings. properties 14 16 20 18 NUMBER with ferrite number of stainless Figure 51. Photograph of small of the tensile deformed specimen and from fractured areas Valve 6. No. Figure 52. Photograph of large of the tensile deformed specimen and from fractured areas Valve 6. No. Figure 53. AISI 4340 ESC valve. Figure 55. Radiographs of Valve No. 3. 162 163 F i g u r e 57. M a c r o s t r u c t u r e o f V a l v e N o . 8 (HC& etch). F i g u r e 58. Macrostructure of V a l v e N o . 13 {HCz e t c h ) . Figure 59. Macrostructure of (top part V a l v e N o . 14 (Hc£ etched for a longer time). etch) Figure 61 . Dendritic structure of Valve No. (a) edge (b) mid-radius (c) centre (d) top 3. Figure 62. Sulphur prints of Valve No. 3. 169 Figure 63. Sulphur Prints of Valve No. 8. 170 Figure 64. Variation of C r , Ni and Mo a c r o s s t h e direction i n V a l v e No. 8. dendritic 171 i Figure 65. 1 1-0 mm Variation of C r , N i a n d Mo a c r o s s t h e direction in V a l v e No. 13. dendritic 173 O 2 » 3 1 5 15 16 17 18 19 _7_ 'E 2 d 21 22 23 24 E 6 m rO 7 _8_ 8 _9_ 9 10 10 II 12 12 _I3 13 14 14 • c » o • o 1 67. Composition (The solid variation line composition.] shows in the I 0 i I ( 3 < 3 < 1 ( J < J 1 < i 4 ( » 3 o 3 3 o i tO-r <£>1 00 QO odd Figure o 4 microprobe o » o 1 Valve < 0 < ^ t£>1 — tO fs_ 00 op 1 to — to ^ CM CM — — — odd No. overall 3. average SQQlf) tO rj- odd 046 0-41 0-36 0-27 0- 2 2 u 017 o u u o u 0 0 u 0 0 0 0 0 Mo 0 1- 9 4 1-84 1-74 Ni 0-84 0-79 0-74 O o o 0 u 0 0 ° o r> n O n O Cr 16 17 18 192 0 21 22 4 23 24 25 26 27 28 29 290 mm. 1 2 3 microprobe 16 17 18 19 20 21 22 23 2 4 2 5 26 27 28 29 4 5 6 _7 E E _8 O CD _9 C\J JO II 12 13 14 •5 12 • o • o • 3 < • o • • • • 0 • • C 0 • • o • o • 0 _. 1 . 1 0 O O 0) f> r - co o o o Composition v a r i a t i o n (The s o l i d line in V a l v e No. shows t h e o v e r a l l » <) <f F i g u r e 68. Ni Cr I *t t 't co cn —- - Mo < < > > <) () < > > ( < { ( > ( < ( ) () > ( c c o c 1° r-OJ 1 p- — c\i CVJ °o 6 8. average composition.) 1 * 1 -r CD CO ro * * 6Qo 175 0-47 0-42 0-37 026 0- 21 XS—O—O— 016 9 O 9 —O D—O 9 ©" 1-94 I 84 1-74 Mo Ni 0-90 0-65 _o 0-80 o o -e--e--e- o o o ~o o Cr 19 20 21 2 2 23 12 24 25 26 27 28 -220 Cr mm.- Ni Mo T" D 8 8 0 D 10 o 20 21 2 2 2 3 12 24 25 26 2 7 2 8 13 Figure 12 13 14 14 15 15 16 S 0 10 microprobe I. 6 17 17 18 18 _L _L _L omo tori co NCJ h- §§§ III sSg 8 S S 69. Composition (The variation sol id'1ine composi t i o n .) shows in the Valve No. overall 13. average 176 050 0-45 040 027 0- 2 2 O 017 O O 0 U ° O O L ) 0 U 0 0 0 0 MO 202 Ni 1- 9 7 1-92 0-90 0-88 o 0-86 ho o o o o o o o o Cr 21122123^4125 262712 28 2 9 3 0 31 3233134 1 2 o o 3 4 o 5 o 2112212324 2 5 E 6 27 2J28|29|30|3l|32|33|34| <> < 8 < 1 Figure 70. > 0 < 12 13 0 14 o 16 16 UJ £ o 0 o o 19 20 1 ? Sfi » Q CO CO CO 6 6 6 line * o 18 Composition v a r i a t i o n (The s o l i d ) ) () 15 J9J c c 7 15 18 c < 11 C c • • • <> 10 Mo c 6 9 microprobe • • o Ni i c • • • • • • • • • • i CM r- CM cn c n o — —Cvl < ) q 0 < ) 0 (> () <> < » ci () <> <> i i n Valve No. 14. shows t h e o v e r a l l average i 040 045 0-50 Cr 017 022 0-27 •295 mm. composition.) (a) Figure 71. Machined (b) AISI 4340 ESC valve 178 Figure 72. Separated surfaces Valve 14. No. along a crack in gure 73. Hardness Valve No. variation 13. in heat-treated 180 I i l l i i • BOTTOM I 29 I 30 I I 31 I 32 HARDNESS Figure 74. Hardness Valve No. variation 14. in L_ 33 (Rc) heat-treated 181 (c) Figure 75. 640 x (d) Microstructure and AISI heat-treated 4340 conditions; heat treated condition, (a), (b) (c) (d) - and Electrode valve - ESC V a l v e in 800 as-cast electrode No. 8 in x (a) (c) Figure 76. 95 x 800 x Microstructure in (b) heat-treated - of AISI 4340 (b) 175 x (d) 800 x No. 13 ESC V a l v e condition, w h i t e a r e a ss grey areas black areas - ferrite bainite (shown i n M a r t e n s i t e (shown (c)) in (d)) Figure 77. Fractographs AISI 4340 of from large tensile ESC V a l v e No. specimens 8. of Figure 78. Orientation the notch in of the Valve charpy No. 8. specimens and 185 T—i—r T—r i i i 60 40 50 30 40 ENERGY (Ft. Lbs.) (Joules) 30 20 20 * • o 10 ESC Valve (Long.) Electrode (Long.) Electrode (Trans.) J 1 1 1 L -100-80-60-40-20 0 20 40 60 80 100 1 1 1 TEMPERATURE (°C) Figure 79. Ductile Brittle transition characteristics o f Valve No. 3 and t h e e l e c t r o d e . Meat T r e a t m e n t : 1 h o u r a t 845°C - o i l q u e n c h . Temper a t 482°C t o a h a r d n e s s o f 39 R c . 187 i—i —i—i 1 — l — I — i — i — i — i — i — r i • Trans. i i -100-80-60-40-20 i i i i i i 0 20 40 60 80 100 TEMPERATURE (°C) Figure 81. Ductile brittle transition characteristics o f Valve No. 1 3 . H e a t T r e a t m e n t : 1 h o u r a t 845°C - o i l q u e n c h . Temper a t 560°C t o a h a r d n e s s o f 35 R c . 65°C Figure 82. Optical and c) fractographs orientations. - L d) - E 100°C of 24°C c h a r p y specimens from V a l v e No. 8 t e s t e d 65°C at different 100°C temperatures Figure 83. Optical fractographs from the a) Long. - AISI 4340 b) of charpy electrode, Trans. specimens 191 Figure 84. SEM f r a c t o g r a p h s (a) (b) ridge area micro-cracks. of charpy specimen 192 (c) Figure 85. 2100 x SEM f r a c t o g r a p h s (d) of different (a) Area 1 (Ridge A r e a ) , (b) Area 2 (Base o f the (c) Area 3 (General Area), (d) Area 4 (Shear Lip A r e a ) , regions 'Low Energy of 2000 a charpy specimen. Fracture . 1 R i d g e ) , Intermediate Energy 1 'High Energy 'High x Fracture'. Energy Fracture'. Fracture'. Figure 8 6 . Soviet electroslag cast valve. b a f i x e d (upside down) (a) and moving (b) core d i e 1-Consumable electrode; 2-Watercooled mold ( c r y s t a l l i z e r ) ; 3-Slag bath; 4-Metal bath; 5c a s t i n g ; 6-Die; 7-Seed charge. Figure 87. Schematic hollow ESC of the methods valves. 3 used for making 195 Figure 90. Macrostructure the welded of insert. the ESC v a l v e with DO NOT COPY LEAVES 1 9 7 - 2 1 2 . APPENDIX 1 ASME/ASTM S P E C I F I C A T I O N S 197 4SI [AMERICAN NATIONAL] iSlANDAHDl ANSI/ASTM A 351 - 77 Used in USAEC-RDT Standards Standard Specification for AUSTENITIC STEEL CASTINGS FOR HIGH-TEMPERATURE SERVICE 1 This Standard is issued under the fixed designation A 351; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last.revision. A number in parentheses indicates the year of last rcspproval. 1. Scope 1.1 This specification* covers austenilic steel castings for valves, flanges, fittings, and oiher pressure-containing parts (Note 1) intended for high-temper2ture and corrosive service (Note 2). NOTE 1—Carbon steel castings for pressure-containing parts are covered by Specification A 2 1 6 , and low.alloy steel castings by Specification A 2 1 7 . NOTE 2 — T h e committee formulating this specification has included 1 7 grades of materials extensively used for the present purpose. It is not the intent that this specification should be limited to these grades. Other compositions will be considered for inclusion by the committee as the need arises. Since these grades possess varying degrees of suitability for high-temperature and corrosion-resistant service, it is the responsibility of the purchaser to determine which grade shall be furnished; due consideration being riven to the requirements of the applicable construction codes. 1.2 Eighteen grades of austenitic steel castings are included in this specification. Selection will depend on design and service conditions, mechanical properties, and the high-temperature and corrosion-resistant characteristics. A 703 Specification for General Requirements Applicable to Steel Castings for Pressure-Containing Parts E 109 Dry Powder Magnetic Particle Inspection E 138 Wet Magnetic Particle Inspection E 165 Recommended Practice for Liquid Penetrant Inspection Method 3 5 5 5 2.2 Manufacturers Standardization Society of the Valve and Fittings Industry Standard: SP 55 Quality Standard for Steel Castings for Valves. Flanges and Fittings and Other Components (Visual Method)* 3. General Conditions for Delivery 3.1 Material furnished to this specification shall conform to the applicable requirements of Specification A 703, including the supplementary requirements that are indicated on the purchaser's order. 3.2 The post weld heat treatment requirements of Supplementary Requirement S l l may be specified when austenitic castings other than H K or H T are to be subjected NOTE 3—The values stated in U.S. customary units to severe corrosive service. are to be regarded as the standard. 2. Applicable Documents 2.1 AS^f Standards: A 216 Specification for Carbon-Steel Castings Suitable for Fusion Welding for HighTemperature Service* A 217 Specification for Martensitic Stainless Steel and Alloy Steel Castings for Pressure-Containing Parts Suitable for HighTemperature Service' A 488 Recommended Practice for Qualification of Procedures and Personnel for the Welding of Steel Castings 4 'This specification is under the jurisdiction of A S T M Committee A - l on Steel, Stainless Steel and Related Alloys and is the direct responsibility of Subcommittee A01.1S on Castings. Current edition approved Oct. 28, 1977. Published December 1977. Originally published as A 351 - 52 T. Last previous edition A 351 - 76. ' F o r A S M E Boiler and Pressure Vessel Code applications, see related Specification SA-351 in Section II of that code. ' Annual Book of ASTM Standards. Paris I and 2. 'Annual Book of ASTM Standards, Part 2. ' A nnuol Book of ASTM Standards. Part 11. 'Available from Manufacturers Standardization Society of the Valve and Fillings Industry, 1815 N . Fort Meyer Drive, Arlington. Va. 22209. 1 9 8 A 351 4. Ordering Information 4.1 The inquiry and order shall include or indicaf the following: 4.1.1 A description of the casting by pattern number or drawing. Dimensional tolerances shall be included on the casting drawing. 4.1.2 Grade of steel. 4.1.3 Options in the specification. 4.1.4 The supplementary requirements desired including the standards of acceptance. 5. Process 5.1 Steel shall be made by the electric furnace process. 6. Heat Treatment 6.1 All castings shall receive a heat treatment proper to their design and chemical composition, except the HK and HT grades which shall be furnished in the as-cast condition. 6.2 Grade C D 4 M C u shall be healed to 2050°F (1120 C) for sufficient time to heat casting uniformly to temperature, furnace cooled to 1900°F (1040°C), held for a minimum of 15 min and quenched in water or rapidly cooled by other means so as to develop acceptable corrosion resistance. o 6.3 The austenitic grades, except Grades HK and HT. shall be solution-treated by the manufacturer. 7. Chemical Requirements 7.1 The steel shall conform to the requirements as to chemical composition prescribed in Table 1. 8. Tensile Requirements 8.1 Steel used for the castings shall conform to the requirements as to tensile properties prescribed in Table 2. castings shall not be furnished under this specification. 10. Quality 10.1 The surface of the casting shall be examined visually and shall be free of adhering sand, scale, cracks, and hot tears. Other surface discontinuities shall meet the visual acceptance standards specified in the order. Visual Method SP 55 or other visual standards may be used to define acceptable surface discontinuities and finish. Unacceptable visual surface discontinuities shall be removed and their removal verified by visual examination of the resultant cavities. 10.2 When additional inspection is desired, Supplementary Requirements S5, S6, and S10 may be ordered. 10.3 The castings shall not be peened, plugged, or impregnated to stop leaks. 11. Repair by Welding 11.1 Repairs shall be made using procedures and welders qualified under Recommended Practice A 488. 11.2 Weld repairs shall be inspected to the same quality standards that are used to inspect the castings. When castings are produced with Supplementary Requirement S5 specified, weld repairs on castings that have leaked on hydrostatic test, or on castings in which the depth of any cavity prepared for repair welding exceeds 20 % of the wall thickness or 1 in. (25 mm), whichever is smaller, or on castings in which any cavity prepared for w-elding is greater than approximately 10 in. (65 cm*), shall be radiographed to the same standards that are used to inspect the castings. When castings are produced with Supplementary Requirement S6 specified, weld repairs shall be inspected by liquid penetrant examination to the same standards that are used to inspect the castings. 8 NOTE 4—When austenitic steel castings are to be used in services where ihey will be subject to stress corrosion, the purchaser should so indicate in his 9.1 Flanged castings that have the flanges order and such castings should be solution-heat removed by machining to make welding end treated following all weld repairs. 9. Flanges SUPPLEMENTARY REQUIREMENTS The following supplementary requirements shall not apply unless specified in the purchase order. A list of standardized supplementary requirements for use at the option of the purchaser is included in Specification A 703. Those which are ordinarily considered suitable for use with this specification are given below. Others enumerated in A 703 may be used with this specification upon agreement between the manufacturer and purchaser. 199 A 351 S2. Destruction Tests. 55. Radiographic Inspection. 56. Liquid Penetrant Inspection. S10. Examination of Weld Preparation. S10.1 The method of performing the magnetic particle or liquid penetrant test shall be in accordance with Method E 109, Method E 138, or Recommended Practice E 165. S l l . Post Weld Heat Treatment. SI 1.1 All austenitic castings, except Grades HK and HT. which have been subjected to weld repairs shall be given a post weld solution heat treatment. TAni.K. 1 Chemical Hcqiiircmrnls Klcmcnl. % (max. Hsccpt Where Range is (iiven) Carbon Manganese Silicon Sulfur Phosphorus Chromium Nickel CI-'.', CI MA Cl R. CI RA CI'.'M. CF.1MA 0.03 1.50 2.00 0.040 0.040 17.021.0 8.012.0 0.0R I.JO 2.00 0.040 0.040 18.021.0 8.011.0 0.0.1 1.50 1.50 0.040 0.040 17.021.6 9.013.0 2.03.0 ... ... r Molybdenum Columbium Copper . . . . ... ... ... CI-RM 0.08 1.50 1.50 0.040 0.040 18.021.0 9.012.0 203.0 ... . ... CIRC CI 18 CI 110 CI 120 CK20 0.08 1.50 2.00 0.040 0.040 18.021.0 9.012.0 0.08 1.50 1.50 0.040 0.040 22.026.0 12.015.0 0.10 1.50 2.01) 0.040 0.010 22.026.0 12.0..15.0 (1.20 1.50 2.00 0.040 0.040 22.026.0 12.015.0 0.20 1.50 1.75 0.040 0.040 23.027.0 19.022.0 0.25-0.35 1.50 1.75 0.040 0.O40 23.027.0 19.022.0 0.15-0.45 1.50 1.75 0.040 0.040 23.027.0 19.022.0 0.25-0.35 2.00 2.50 0.040 0.040 ' ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... IIK40 11K .10 irr.m 1.1.017.0 33.037.0 0.50 CI I0MC CN7M C04MC 0.10 1.50 1.50 0.040 0.040 15.018.0 13.016.0 1.752.25 0.07 1.50 1.50 0.040 0.040 19.022.0 27.530.5 2.03.0 0.04 1.00 l.(X) 0.04 0.04 24.526.5 4.756.00 1.752.25 " . . . ... J.04.0 ... 2.753.25 * Grade C F 8 C shall have a columbium contcnl of not less lhan R limes the carbon cnnlcnl but nol over 100 % . " Grade C F I 0 M C shall have a columbium conlenl of no! less lhan 10 limes the carbon content bul nol over 1.20 % . TABI.F. 2 CF3 70 Tensile .strength, min, ksi (4851 (MPa) Yield strength." min, ksi (MPa) 30 (205) 35.0 Elongation in 2 in. or 50 mm. min. % Rcduclion of area. min. % Tensile Requirement CF3A' CFR CF8A' CF3M CT3MA CIRM CIRC CUR CI 110 CI 120 CK20 1IK30 77 (530) 35 (240) 35.0 70 (4R5) 30 (205) 35.0 77 (530) 35 (240) 35.0 70 (485) 30 (205) 30.0 •80 (550) 37 (255) 30.0 70 (485) 30 (205) 30.0 70 (485) 30 (205) 30.0 65 (450) 2R (195) 30 0 70 (4R5) 30 (205) 30.0 65 62 (4 50) (425) 35 35 (240) (240) 10.0 10.0 70 (4R5) 30 (205) 30.0 65 (450) 2K (195) 30.0 IIK40 11130 CI-I0MC CN7M CU 4MCu 65 (450) 28 (195) 15.0 70 (4R5) 30 (205) 20.0 62 (425) 25 (170) 35.0 100 (690) 70 (485) 16.0 * The properties shown are obtained by adjusting the composition within the limits shown in Table t to obtain a fcrritc-ausicnitc ratio that wilt result in the higher ultimate and yield strengths indicated. Because of the thermal instability of Grades C F 3 A , C F 3 M A . and C F K A , they arc not recommended for service at temperatures in excess of 800"F (425"C). * Determine by either 0.2 % offset method or 0.5 % cxlcnsion-undc'r-load mclhod. The American Society for Testing and Materials takes no position respecting the validity of any patent rights asserted in connection with any item mentioned in this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the risk of infringement of such rights, is entirely their own responsibility. 201 (AMERICAN NATIONAL") (STANDARD! ANSI/ASTM A 182-77a .Endorsed by Manufacturers Standardization Society of the Valve and Finings Industry Used in USAEC-RDT standards Standard Specification for FORGED OR R O L L E D FORGED FITTINGS, A N D A L L O Y - S T E E L PIPE VALVES HIGH-TEMPERATURE SERVICE AND FLANGES, PARTS FOR 1 This Standard is issued under the fixed designation A 182; the number immediately following the designation indicates the year of original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of iast reapprovaj. • 1, Scope 1.1 This specification covers forged low alloy and stainless steel piping components for use in pressure systems. Included are flanges, fittings, valves, and similar pans to specified dimensions or to dimensional standards such as the ANSI specifications that are referenced in Section 2. 1.2 Other forgings for other applications may be made to this specification. 1.3 Thirty-three grades are covered including sixteen ferritic or. martensitic steels and seventeen austenitic stainless steels. Selection will depend upon design and service requirements. 1.4 Supplementary requirements are provided for use when additional testing or inspection is desired. These shall apply only when specified individually by the purchaser in the order. N O T E 1—The values staled in U . S . customary units are to be regarded as the standard. 2. Applicable Documents E 165 Recommended Practice for Liquid Penetrant Inspection Method E 353 Chemical Analysis of Stainless, Heat-Resisting, Maraging, and Other Similar, Chromium-Nickel-Iron Alloys E 381 Rating Macroetched Steel 6 5 3 2.2 Manufacturers' Standardization Society of the Valve and Fittings Industry Standard: 7 SP 25 Standard Marking System for Valves, Fittings. Flanges and Unions. 2.3 ASME Boiler and Pressure Vessel Code:* Section IX Welding Qualifications SFA-5.4 Specification for Corrosion-Resisting Chromium and Chromium-Nickel Steel Covered Welding Electrodes SFA-5.5 Specification for Low-Alloy Steel Covered Arc-Welding Electrodes 2.4 American National Standards Institute Standards:' B16.5 Dimensional Standards for Steel Pipe Flanges and Flanged Fittings This specification is under the jurisdiction of A S T M Committee A - l on Steel. Stainless Steel and Related A l loys, and is the direct responsibility of Subcommittee A01.22 on Valves and Finings. Current edition approved Oct. 28. 1977. Published December 1977. Originally published as A 182 - 35 T . Last previous edition A 182 - 77. ' Annual Book of A S T M Standards, Pan 1 . ' Annua! Book of A S T M Standards, Pan 5. ' Annual Book of A S T M Standards, Pans 1 , 2 , 3 , 4 , 5 , and 10. • Annual Book of A S T M Standards, Pan 12. • Annual Book of A S T M Standards, Pan 1 ] . ' Available from Manufacturers' Standardization Society of the Valve and Fittings Industry. 1815 N. F o n Myer Drive, Arlington, V a . 22209. Available from American Societv of Mechanical Engineers, 345 E. 47th St., New York. N.Y. 10017. • Available from American National Standards Institute, 1430 Broadway, New York, N. Y . 10018. 1 2.1 ASTM Standards: A 234 Specification for Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and Elevated Temperatures A 275 Magnetic Particle Examination of Steel Forgings A 370 Mechanical Testing of Steel Products A 509 Definition of a Steel Forging E 30 Chemical Analysis of Steel, Cast Iron. Open-Hearth Iron, and Wrought Iron 5 5 4 3 5 6 1 202 A 162 - ' ; v Vi- (667°C). Grade F6a Class 1 shall be tern-* pered at not less than 132ST (717°C); Grade F6a Class'3 at not less than 1100°F (593°C); and F6a Class 4 at not less than lOOO'F-. (538°C). 3. Basis of Purchase 5.1.1 Grade F 6a (martensitic) Classes 1 3.1 Orders for material under this specifica- and 2 need be tempered only, provided the tempering temperature for Class 1 is not less tion shall include the following information, as necessary, to describe adequately the de-. than 1325T (667°C) and for Class 2, not less than 1250°F(667 C).... sired material: 5.1.2 Grade F 6NM shall be furnished in 3.1.1 Name of forging, 3.1.2 ASTM specification number includ- the normalized and tempered condition; the tempering temperature shallbe not less than • trig grade, 1040°F (560 C) nor greater than 1120°F 3.1.3 Size and pressure class or geometry, (600 C). 3.1.4 Quantity, 5.2 Liquid quenching followed by temper3.1.5 Test report if required, and ing shall be permitted when agreed to by the 3.1.6 Supplementary requirements, if any. purchaser. The same, minimum tempering temperature as specified in 5.1 shall be re4. Manufacture , 4.1 The low-alloy ferritic steels may be quired for each grade. Parts that are liquid made by the open-hearth, electric-furnace, or quenched and tempered shall be marked basic-oxygen process. The basic-oxygen "QT" and shall be inspected for quench process shall be limited to steels containing cracks by the magnetic particle method in accordance with Method A 275. less than 2 % chromium. 5.3 All austenitic material shall be fur4.2 The stainless steels shall be melted by one of the following processes: (a) electric- nished in the heat-treated condition. The heat furnace (with separate degassing and refining treatment shall consist of heating the material optional); (b) vacuum-furnace; or (c) one of to a minimum temperature of 1900'F (1040°C) the former followed by vacuum or electro- and quenching in water or rapidly cooling by slag-consumable remelting. Grade XM-27 may other means, except for grades F 321H. F 347H, and F 348H, which shall be solution be produced by electron-beam melting. 4.3 A sufficient discard shall be made to treated at 1925T (1050°C) min. 5.4 Heat treatment may be performed besecurefreedomfrom injurious piping and unfore machining. " due segregation. . 4.4 The material shall be forged as close as 6. Chemical Requirements practicable to the specified shape and size. 6.1 The steel shall conform to the requireForged or rolled bar may be used without ments as to chemical composition for the additional hot working for small cylindrically grade ordered as listed in Table 1. For referee shaped parts within the limits defined by purposes, Methods E 30 or E 353 shall be Specification A 234. used. 4.5 The finished product shall be a forging 6.2 Grades to which lead, selenium, or as defined by Definition A 509. other elements are added for the purpose of rendering the material free-machining shall 5. Heat Treatment not be used. 5.1 The ferritic grades and the martensitic grade shall be annealed, or normalized and 7. Cast or Heat (formerly Ladle) Analysis tempered, except as permitted in 5.2. If fur7.1 An analysis of each heat of steel shall nished in the normalized and tempered condibe made from samples taken preferably durtion, the tempering temperature for Grades F ing the pouring of the heat and the results 1, F 2, F 11 and F 12 shall be not less than shall conform to Table 1. 1150°F (620°C). The minimum tempering 8. Product Analysis temperature for Grades F5. F5a, F6a Class 2, F7, F9, F21, and F22 shall be 1250°F 8.1 The purchaser may make a product B16.ll Forged Steel Fittings, Socket Weld, and Threaded B16.10 Face-lo-Face and End-to-End Dimensions of Ferrous Valves e e o ; 203 A 182 analysis on forgings supplied to this specification. Samples for analysis shall be taken from midway between the center and surface of solid forgings, midway between the inner and outer surfaces of hollow forgings, midway between the center and surface of full-size prolongations, or from broken mechanical test, specimens. The chemical composition thus determined shall conform to Table 1 with the tolerances as staled in Table 2 or 3. 9. Mechanical Requirements 9.5.2 Austenitic Stainless Steel Grades- One tension test shall be made for each heat. N O T E 2 — "Type" in this case is used to describe the forging shape such as a flange, ell, tee, etc. .9.5.3 Testing shall be performed in accordance with Methods A 370 using the largest feasible of the round specimens. The gage length for measuring elongation shall be four, times the diameter of the test section. 9.6 Hardness Tests: 9.6.1 Sufficient number of hardness measurements shall be made in accordance with 9.1 The material shall conform to the reMethods A 370 to assure that the forgings are quirements as to mechanical properties for within the hardness limits given for each grade the grade ordered as listed in Table 4. in Table 4. The purchaser may verify that the 9.2 Mechanical test specimens shall be obrequirement has been met by testing at any tained from production forgings after heat location on the forging provided such testing treatment, or from separately forged test does not render the forging useless. blanks prepared from the stock used to make 9.6.2 When the reduced number of tension the finished product. Such test blanks shall tests permitted by 9.5.1.1 is applied, addireceive approximately the same working as tional hardness tests shall be made on forgings the finished product. The test blanks shall be or samples as defined in 9.2. scattered heat-treated with the finished product and throughout the load (Note 3). A t least.eight shall approximate the maximum cross section samples shall be checked from each batch load of the forgings they represent. and at least one check per hour shall be made 9.3 For normalized and tempered, or from a continuous run. When the furnace quenched and tempered forgings, the central batch is less than eight forgings, each forging axis of the specimen shall correspond to the shall be checked. If any check falls outside the 'I* t plane or deeper position in the thickest prescribed limits, the entire lot of forgings section, /, of the represented forgings and the shall be reheat treated and the requirements gage length shall be at least t distance from a of 9.5.1 shall apply. second heat-treated surface. When section N O T E 3—The tension test required in 9.5.1 is thickness or geometry interferes, the speciused to determine material capability and conformmen shall be positioned as near as possible to ance in addition to verifying the adequacy of the the prescribed location. heat-treatment cycle. Additional hardness tests in accordance with 9.6.2 are required when 9.5.1.1 is 9.4 For annealed ferritic and martensitic applied to assure the prescribed heat-treating cycle grades and also for austenitic stainless steels, and uniformity throughout the load. . . . the test, specimen may be taken from any 10. Retreatment convenient location, e : : 9.5 Tension Tests:] •• •* - ..• 10.1 If the results of the mechanical tests 9.5.1 Ferritic and Martensitic Grades — do not conform to the requirements specified, One tension test shall be made for each heat in each heat treatment charge. 9.5.1.1 When the heat-treating cycles are the same and the furnaces (either batch or continuous type) are controlled within ± 25°F" (± 14°C) and equipped with recording pyrometers so that complete records of heat treatment are available, then only one tension test from each heat of each forging type (Note 2) and section size is required instead of one test from each heat in each heat-treatment charge. --i;.-. the manufacturer may reheat treat the forgings and repeat the tests specified in Section 9. 11. Finish 11.1 The forgings shall be free of scale, machining burrs which might hinder fit-up, and other injurious imperfections as defined herein. The forgings shall have a workmanlike finish and machined surfaces (other than surfaces having special requirements) shall have a surface finish not to exceed 250 A A 204 A 182 (ariihmetic average) roughness height. 11.2 At the discretion of the inspector representing the purchaser, finished forgings shall be subject to rejection if surface imperfections acceptable under 11.4 are not scattered but appear over a large area in excess of what is considered to be a workmanlike finish. IX of the A S M E Boiler and Pressure Vessel Code. 12.1.2 The weld metal shall be deposited using the electrodes specified in Table 5. The electrodes shall be purchased in accordance with A S M E Specifications SFA-5.4 or SFA5.5. 12.1.3 Defects shall be completely re11.3 Depth of Injurious Imperfections— moved prior to welding by chipping or grindLinear imperfections shall be explored for ing to sound metal as verified by magnetic depth. When the depth encroaches on the particle inspection in accordance with minimum wall thickness of the finished forg- Method A 275 for the ferritic or martensitic ing, such imperfections shall be considered grades, or by liquid penetrant inspection in injurious. accordance with Recommended Practice 11.4 Machining or Grinding ImperfectionsE 165 for ferritic, martensitic, or austenitic Not Classified as Injurious—Surface imper- grades. 12.1.4 After repair welding, the welded fections not classified as injurious shall be area shall be ground smooth to the original treated as follows: contour and shall be completely free of de11.4.1 Seams, laps, tears, or slivers not fects as verified by magnetic-particle or liqdeeper than 5 % of the nominal wall thickness uid-peneirant inspection, as applicable. or Vi« in. (1.6 mm), whichever is less, need 12.1.5 The preheat, interpass temperanot be removed. If these imperfections are ture, and post-weld heat treatment requireremoved, they shall be removed by machinments given in Table 5 shall be met. ing or grinding. 12.1.6 Repair by welding shall not exceed 11.4.2 Mechanical marks or abrasions and 10 % of the surface area of the forging nor pits shall be acceptable without grinding or 33 >h % of the wall thickness of the finished machining provided the depth does not exceed the limitations set forth in 11.4.1. Imper- forging or lt in. (9.5 mm), whichever is less, without prior approval of the purchaser. fections that are deeper than '/it in. (1.6 mm), 12.1.7 When approval of the purchaser is but which do not encroach on the minimum obtained, the limitations set forth in 12.1.6 wall thickness of the forging shall be removed may be exceeded, but all other requirements by grinding to sound metal. of Section 12 shall apply. 11.4.3 When imperfections have been removed by grinding or machining, the outside dimension at the point of grinding or machin13. Marking ing may be reduced by the amount removed. 13.1 Identification marks consisting of the Should it be impracticable to secure a direct manufacturer's symbol or name, designation measurement, the wall thickness at the point of service rating, the specification number, of grinding, or at an imperfection not required the designation, F 1, F 2, etc.. showing the to be removed, shall be determined by deduct- grade of material, and the size shall be legibly ing the amount removed by grinding from the stamped on each forging or the forgings may nominal finished wall thickness of the forgbe marked in accordance with Standard SP 25 ing, and the remainder shall be not less than of the Manufacturers' Standardization Socithe minimum specified or required wall thickety of the Valve and Fittings Industry, and in ness. such position so as not to injure the usefulness of the forging. 12. Repair by Welding 13.1.1 Quenched and tempered ferritic or 12.1 Weld repairs shall be permitted (see martensitic forgings shall be stamped with the Supplementary Requirement S7) at the disletters QT following the A S T M designation. cretion of the manufacturer with the following 13.1.2 Forgings repaired by welding shall limitations and requirements: be marked with the letter "W" following the 12.1.1 The welding procedure and welders A S T M designation. shall be qualified in accordance with Section 13.1.3 When test reports are required, the l 205 0» markings shall consist of the manufacturer's symbol or name, the grade symbol, and such other markings as necessary to identify the part with the test report (13.1.1 and 13.1.2 shall apply). 14. Inspection 14.1 The manufacturer shall afford the purchaser's inspector all reasonable facilities necessary to satisfy him that the material is being furnished in accordance with the purchase order. Inspection by the purchaser shall not interfere unnecessarily with the manufacturer's operations. All tests and inspections shall be made at the place of manufacture unless otherwise agreed upon. A 182 as required in 13.1 shall be the certification that the forgings have been furnished in accordance with the requirements of this specification. 15.2 Test reports, when required, shall include certification that all requirements of this specification have been met, the results of all required tests, and 'the type of heat treatment. 16. Rejection 16.1 Each forging that develops injurious defects during shop working operations or in service shall be rejected and the manufacturer notified. 17. Rehearing 15. Certification 17.1 Samples representing material re15.1 For forgings made to specified dimen- jected by the purchaser shall be preserved sions, when agreed upon by the purchaser, until disposition of the claim has been agreed and for forgings made to dimensional standupon by the manufacturer and the purchaser. ards, the application of identification marks SUPPLEMENTARY REQUIREMENTS The following supplementary requirements shall apply only when specified by the purchaser in the inquiry, contract, and order. » 51. Macroetch Test S l . l A sample forging shall be sectioned and etched to show flow lines and internal imperfections. The test shall be conducted according to Method E 381. Details of the test shall be agreed upon between the manufacturer arid the purchaser. 52. Product Analysis S2.1 A product analysis in accordance with Section 8 shall be made from one randomly selected forging representing each size and type (Note 2) of forging on the order. If the analysis fails to comply, each forging shall be checked or the lot rejected. All results shall be reported to the purchaser. 53. Heat Identification and Tension Tests S3.1 In addition to the requirements of Section 9, the heat identification shall be marked on each forging and one tensile specimen shall be obtained from a representative forging from each heat at a location agreed upon between the manufacturer and the purchaser. The results of the test shall comply with Table 4 and shall be reported to the purchaser. 54. Magnetic Particle Examination S4.1 All accessible surfaces of the finished forging shall be examined by a magnetic-particle method. The method shall be in accordance with Method A 275. Acceptance limits shall be as agreed upon between the manufacturer and purchaser. 55. Liquid Penetrant Examination S5.1 All accessible surfaces shall be examined by a liquid penetrant method in accordance with Recommended Practice E 165. Acceptance limits shall be as agreed upon between the manufacturer and the purchaser. 56. Hydrostatic Testing S6.1 A hydrostatic test at a pressure agreed upon between the manufacturer and the purchaser shall be applied by the manufacturer. 206 • 4SID A 182 S7. Repair Welding S8. Heat Treatment Details S7.1 No repair welding shall be permitted without prior approval of the purchaser. If permitted, the restrictions of Section 12 shall S8.l The manufacturer shall furnish a de-' tailed test report containing the information required in 15.2 and shall include all pertinent details of the heat-treating cycle given the forgings. ; apply- TAM.F, I Chemical Requirement* Composition. % Identification Symbol Grade Carbon Manganese Phosphorus. max 0.28 max 0.21 max 0.60-0.90 0.30-0.80 0.045 0.040 0.045 0.04(1 0.15-0.35 0.10-0.60 0.15 0.25 0.15 0.1S 0.30-0.60 0.60 max 1.00 max 1.00 max 0.030 0.040 0.040 0.02 0.030 0.0.30 0.030 0.02 0.50 max 0.50 max 1.00 max 1.0 max 0.06 max 0.15 max 0.15 max 0.10-0.20 0.50-1.00 0.30-0.60 0.30-0.60 0.30-0.80 0.030 0.030 0.030 0.040 0.030 0.030 0.030 0.040 0.10-0.20 0.30-0.80 0.040 0.15 max 0.15 max 0.010 max 0.30-0.60 0.30-0.60 0.40 max 0.040 0.040 0.020 Sulfur, max Silicon Nickel Chromium Molybdenum Columbium plus Tantalum Tantalum, max Titanium Ferritic Steels F 1 F 2« carbon-molybdenum 0.5 % chromium, 0.5 % molybdenum F3» 4 to 6 % chromium F 5a* 4 to 6 % chromium F6a 13 % chromium F6b 13 % chromium, 0.5 % molybdenum F 6NM 13 % chromium. 4 % nickel F7 6 to 8 % chromium F9 9 % chromium F 11 1.25 % chromium, 0.5 % molybdenum F 12 1 % chromium, 0.5 % molybdenum F 21 chromium-molybdenum F 22 chromium-molybdenum F XM-27* 27 chromium, 1 molybdenum max max max max 0.50-0.81 0.50 max 0.50 max 0.50 max 1.0-2.0 0.44-0.65 0.44-0.65 4.0-6.0 4.0-6.0 11.5-13.5 11.5-13.5 0.44-0.65 0.44-0.65 0.30-0.60 3.50-4.50 0.50-1.00 0.50-1.00 0.50-1.00 12.00-14.00 6.0-8.0 8.0-10.0 1.00-1.50 0.30-0.70 (1.44-0.65 0.90-1.10 0.44-0.65 0.040 0.10-0.60 0.80-1.25 0.44-0.65 0.040 0.040 0.020 0.50 max 0.50 max 0.40 max 2.65-3.35 2.00-2.50 25.00-27.50 0.80-1.06 0.87-1.13 0.75-1.50 F 429 F430 15 chromium 17 chromium 0.12 max 0.12 max F 304 F 30411 F304L 18 chromium, S nickel 18 chromium, 8 nickel 18 chromium, 8 nickel, low carbon 18 chromium, 8 nickel, modiTied with nitrogen 25 chromium, 20 nickel 18 chromium, 8 nickel, modiTied with molybdenum 18 chromium, 8 nickel, modified with molybdenum 18 chromium, 8 nickel, modiTied with molybdenum, low carbon 0.08 max 2.00 max 0.04-0.10 2.00 max 0.035 max 2.00 max 0.040 0.040 0.040 0.030 0.030 0.030 0.08 max 2.00 max 0.030 0.15 max 0.08 max 2.00 max 2.00 max 0.04-0.10 0.50 max 0.40-0.60 0.50 max 0.50 max 14.0-16.0 16.0-IR.O 1.00 max 1.00 max 1.00 max 8.00-11.00 8.00-11.00 8.00-13.00- IR.00-20 00 IR.00-20 00 18.00-20. 00 . .. . .. ... 0.030 0.75 max 8.00-10.50 18.00-20..00 ... 0.040 0.040 0.030 0.030 1.00 max i.OOmax 19.00-22.00 24.00-26 .00 . . . 10.00-14.00 16.00-18, ,00. 2.00-3.00 2.00 max 0.04 0 0.030 I.OOmax 10.00-14.00 16.00-18 0.035 max 2.00 max 0.040 0.030 I.OOmax 10.00-15.00 16.00-18. 1.00 max 1.00 max 0.040 0.040 0.030 0.030 0.75 max 0.75 max Other Elements Cu 0.50 max Other F.lcmcnts N 0.015 max Cu 0.20 max CO to Austenitic Steels F304N' F.1I0 F316 F 31AM F3I6L 00 2.00-3.00 00 2.00-3.00 O <1 TAIiLF. i Continued Composition. % Identification Symbol F316N' F 321 F 32111 F347 F 34711 F348 F 348H FXM-19 F 10 Gnulc 18 chromium, 8 nickel, modified with molybdenum and nitrogen 18 chromium, 8 nickel modified with titanium ]R chromium, 8 nickel, modified with titanium 18 chromium, R nickel modified with columbium 18 chromium, 8 nickel, modified with columbiuni IR chromium, 8 nickel modified with columbium IR chromium, R nickel, modified with columbium 22 chromium, 13 nickel, 5 manganese 20 nickel, 8 chromium t Carbon Manganese Phosphorus, max SulHir. max Silicon 0.08 max 2.00 max 0.030 0.030 0.75 max 11.00-14.00 16.00-18.00 0.08 max 2.00 max 0.030 0.030 1.00 max 9.00-12.00 17.00 min 0.04-0.10 2.00 max 0.030 0.030 1.00 max 9.00-12.00 17.00 min 0.08 max 2.00 max 0.030 0.030 1.00 max 9.00-13.00 17.00-20.00 0.04-0.10 2.00 max 0.030 0.030 1.00 max 9.00-13.00 17.00-20.00 0.08 max 2.00 max 0.030 0.030 1.00 max 9.00-13.00 17.00-20.00 0.04-0.10 2.Of) max 0.030 0.030 1.00 max 9.00-13.00 17.00-20.00 0.06 max 4.00-6.00 0.040 0.030 1.00 max 11.50-13.50 20.50-23.50 0.10-0.20 0.50-0.80 0.030 0.030 1.00-1.40 19.00-22.00 7.00-9.00 Nickel Chromium Molybdenum Colli mbium plus 'Iantalum Tantnlum, max Tilnnium -3.00 -3.00 0.10-0.30 Other Elements N 0.20-0.40 V 0.10-0.30 * Grade F 2 was formerly assigned lo the I % chromium, 0.5 % molybdenum grade which is now Grade F 12. * The present grade F 5a (0.25 max carbon) previous to 1955 was assigned the identificatiop symbol F 5. Identification symbol F 5 in 1955 was assigned lo the 0.15 max carbon grade to be consistent with A S T M specifications for other products such as pipe, lulling, boiling, welding fittings, etc. Grade F XM-27 shall have a nickel plus copper content of 0.50 max % . Product analysis tolerance over the maximum specified limit for carbon and nitrogen shall be 0.002 % . c * Grades F 304N and F 3I6N shall have a nitrogen content of 0.10 to 0.16 % . ' Grade F 321 shall have a titanium content of not less than five times the carbon content and not more than 0.60%. ' G r a d e F 321H shall have a titanium content of not less lhan 4 times the carbon conlcnl and not more lhan 0.60 % . * Grades F 347 and F 348 shall have a columbium plus tantalum conlcnl of not less than ten limes the cnrbon content and not more lhan 1.00 % . * Grades F 34711 and F 348H shall have a columbium plus tantalum content of not less than 8 times Ihc carbon content and nor more lhan 1.00 % . 209 iSlI A 182 5 TABLE 2 Element Limit or Maximum of Specified Range, % Product Analysis Tolerances for Low-Alloy Steels Tolerance Over Maximum Limit or Under Minimum Limit for Size Ranges Shown. * • 100 in. (6.45 x 10* mm«). or less 1 Over 100 to 200 in.' (1.290 x lO* mm'), incl Over 200 to 400 in.' (2.58! x 10= mm'), incl Over 400 in.' Manganese to 0.90 incl over 0.90 to I.00 incl 0.03 0.04 0.04 0.05 0.05 0.06 0.06 0.07 Phosphorus to 0.045 incl 0.005 0.010 0.0)0 0.010 Sulfur to 0.045 incl 0.005 0.010 0.010 0.010 Silicon to 0.40 incl over 0.40 to l.OO incl 0.02 0.05 0.02 0.06 0.03 0.06 0.04 0.07 Nickel to 0.50 0.03 0.03 0.03 0.03 Chromium to 0.90 incl over 0.90 to M O incl over 2.10 to 3.99 incl 0.03 0.05 0.10 0.04 0.06 0.10 0.04 0.06 0.12 ' 0.05 0.07 0.14 Molybdenum to 0.20 incl over 0.20 to 0.40 incl over 0.40 to LIS incl 0.01 0.02 0.03 0.01 0.03 0.04 0.02 0.03 0.05 0.03 0.04 0.06 •.Cross-seciionaJ area 210 lull? TABLE 4 r-.A- c. _ u , i Grade Symbol Fcrriiic Steels: F 1 F 2 F 5 F 5a F 6a Class 1 F 6a Class 2 F6a Class 3' F 6a Class 4' F 6b F 6NM F 7 F 9 F 11 F 12 F 21 F 22 F XM-27 F429 F 4 30 \usienitic Steels: F 304 F 304'H F 304L F 504 N F310 F 316 F 316H F 316L F 316N F 347 F 347H F 348 F 34SH F 321 F 321H F XM-19 F 10 • ' ' ' ' T.„,;I. c , , . „ „ - v tensile Mrenpin, . , cL, mm. ksi (MPa) w ; W A 182 Tensile and Hardness Requirements Yield Strencih. , . , mm. ksi (MPa) (0.2 * offset) 70 (483) 70(483) 70 (483) 90 (621) 70 (483) 85(586) 110 (758) 130 (896) 110-135 (758-930) 110-135(758-930) 70 (483) 85 (586) 70 (483) 70 (483) 75 (517) 75 (517) 60 (414) 60(414) 60(414) 40(276) 40 (276) 40 (276) 65 (44 S) 40 (276) 55 (379) 85 (586) 1 10 (758) 90 (621) 90 (621) 40(276) 55(379) 40 (276) 40(276) 45 (310) 45 (310) 35 (241) 35(241) 35 (241) 75 (517)" 75 (517f 70 (483)° 80 (552) 75 (517)75 (S17)r 75 (517F 70 (483^ 80 (552) 75 (517)" 75 (517)° 75 (517)" 75(517)" 75 (517f 75 (517)° 100 (690) 80(552) 30 (207) 30 (207) 25 (172) 35(241) 30 (207) 30 (207) 30 (207) 25 (172) 35 (241) 30 (207) 30 (207) 30(207) 30 (207) 30 (207) 30 (207) 55 (380) 30 (207) Elongation in ., . « 2 in. or 50 mm. min,* r . • , Reduction of Zj' A Area, min, % c 25.0 20.0 20.0 " 22.0 18 IS 18 18 16 15 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 20.0 35.0 30.0 35.0 50.0 35.0 35.0 35.0 35.0 45.0 35.0 35.0 40.0 30.0 30.0 30.0 30.0 45.0 45.0 45.0 30 30 30 30" 30 30 30 30 30" 30 30 30 30 30 30 50 50 50 50 50 50 50 50 50" 50 50 50 50 50 50 55 50 35 30 1 For sections over 5 in. in thickness, the minimum tensile strength shall be 70 ksi (483 MPa). For sections over 5 in. in thickness, the minimum tensile sttength shall be 65 ksi (448 M P a ) . Longitudinal. The transverse elongation shall be 25 % in 2 in. or 50 mm, min. Longitudinal. The transverse reduction of area shall be 45 % min. No weld repair is permitted for these classes. Brinell HardX. , ness Number, m a x 143-192 143-192 143-217 187-248 143-187 167-229 207-302 263-321 235-285 235-285 143-217 179-217 143-207 143-207 156-207 156-207 190 max 190 max 190 max 211 iSlfr A182 TABLE 3 Product Analysis Tolerances for Higher A Do; and Stainless Steels" Elements Limit or Maximum of Specified Range, % Tolerance Over the Maximum Limit or Under the Minimum Limit Carbon 0.030, i n d over 0.030 to 0.20 ind 0.005 0.01 Manganese to 1.00, ind over 1.00 to 2.00, i n d 0.03 0.04 Phosphorus to 0.040, ind 0.005 Sulfur to 0.030, ind 0.005 Silicon to 1.00, ind over 1.00 to 1.40, ind 0.05 0.10 Chromium over over over over 4.00 to 10.00, ind 10.00 to 15.00, ind 15.00 to 20.00, i n d 20.00 to 27.50, ind 0.10 0.15 0.20 0.25 Nickel to 1.00, ind over 1.00 to 5.00, ind over 5.00 to 10.00, ind over 10.00 to 20.00, ind over 20.00 to 22.00, incl 0.03 0.07 0.10 0.15 0.20 . Molybdenum over 0.20 to 0.60, incl over 0.60 to 1.75. ind over 1.75 to 3.00, ind 0.03 0.05 ..10 Titanium Columbi urntantalum Tantalum Cobalt Nitrogen aU ranges aU ranges 0.05 0.05 to 0.10, ind 0.05 to 0.20, ind to 0.16, ind 0.02 0.01» 0.01 « This table does not apply to heat analysis. ' Product analysis limits for cohalt under 0.05% have not been established and the producer should be consulted for those limits. 212 # A 182 T A B L E 5 Repair Welding Requirements Grade Symbol Ferritic Steels: F 1 F2 F 5 F 5a F6a F 6b F 6NM F 7 F9 F 11 F 12 F 21 F 11 F XM-27 F429 F430 Austenitic Steels: F304 F 304L F 304H F 304N F 310 F316 F 316L F 316K F 31bN F 321' F321H' F347 F 347H F34S F34SH F XM-19 F 10* • • ' • Electrodes* Recommended Preheat and Interpass Temperature Range; F CO E 7018-A 1 E 801 g-B 1 E 502-15 or 16 E 502-15 or 16 E 410-15 or 16 13 % C r , l'/j % N i , '/.- % M o 13 % C r , 4 % Ni E 7 Cr-15 E 505-15 or 16 E 8018-B 2 E 8018-B 2 E9018-B3 E 9018-B 3 26 * C r , 1 % M o E 430-16 E 430-16 0 200-400 (95-205) 300-600 (150-315) 400-700 (205-370) 400-700 (205-370) 400-700 (205-370) 400-700 (205-370) 300-700 (150-370) 400-700 (205-370) 400-700(205-370) 300-600(150-315) 300-600(150-315) 300-600(150-315) 300-*00(150-315) NR< 400-700 (205-370) NR E 308-15 or 16 E 308L-15 or 16 E 308-15 or 16 E 308-15 or 16 E 310-15 or 16 E 316-15 or 16 E 3I6L-15 or 16 ~ E 316-15 or 16 E 316-15 or 16 E 347-15 or 16 E 347-15 or 16 E 347-15 or 16 E 347-15 or 16 E 347-15 or 16 E 347-15 or 16 XM-J9W Electrodes shall comply with A S M E S F A 5.4 or S F A 5.5. Purchaser approval required. N R = not required. W Q = water quench. TntArntricanSo^ryforTts,^ NR NR NR NR NR NR NR NR NR NR NR NR NR NR NR NR NR Minimum Post Weld HeatTreatment Temperature ° F 0 Q 1150 (620) 1150(620) 1250 (677) 1250 (677) 1400 (760) 1150 (620) 1050 (565) 1250 (677) 1250 (677) 1150 (620) 1150 (620) 1250 (677) 1250 (677) NR 1400 (760) 1400 (760) 1900(1040) + WQ< 1900(1040) + WQ 1900(1040) + WQ 1900(1040) + W Q 1900(1040) + WQ 1900(1040) + W Q 1900(1040) + W Q 1900(1040) + W Q 1900(1040) + W Q 1900(1040) + WQ 1925 (1050) + WQ 1900(1040) + W Q 1925 (1050) + W Q 1900(1040) + W Q 1925 (1050) + WQ NR NR
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Electroslag casting of valve bodies Gupta, Deepak 1982
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Title | Electroslag casting of valve bodies |
Creator |
Gupta, Deepak |
Date Issued | 1982 |
Description | The Electroslag Casting (ESC) process has been widely used in the Soviet Union for the production of high quality steel castings. This work presents the results of an examination of the ESC process for the production of simple shaped valve bodies. Stainless steel (AISI 316 and ACI CF-8M) and low alloy steel (AISI 4340) valve bodies were made at U.B.C. and tested by non-destructive and destructive methods. It is concluded that this technique offers distinct quality and production advantages and the properties easily meet the required ASME/ASTM specifications. Therefore they are equivalent to or better than the conventional castings and forgings. However, there may be difficulties in reconciling the method with present code qualification requirements. |
Genre |
Thesis/Dissertation |
Type |
Text |
Language | eng |
Date Available | 2010-03-31 |
Provider | Vancouver : University of British Columbia Library |
Rights | For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use. |
DOI | 10.14288/1.0078736 |
URI | http://hdl.handle.net/2429/23175 |
Degree |
Master of Applied Science - MASc |
Program |
Metals and Materials Engineering |
Affiliation |
Applied Science, Faculty of Materials Engineering, Department of |
Degree Grantor | University of British Columbia |
Campus |
UBCV |
Scholarly Level | Graduate |
Aggregated Source Repository | DSpace |
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