I can never tell what the American standard castings for F321 and F347 are; is CF8C equivalent to F321? What about F347?
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Please ask the experts to take a look; thank you very much
This post was last edited by hlcl on 2016-11-5 11:01; it refers to the casting corresponding to SS347 in CF8C. F347 is a forged version of SS347. CF3=304L CF3M=316L CF8=304 CF8M=316 CF8C=347(0Cr18Ni11Nb)
F321 contains Ti, while F347 contains Nb. I remember it as a F321 casting of CF8C? If not, then what material is the casting of F321 made of?
This post was last edited by hlcl on 2016-11-5 at 11:27. I have never seen a casting grade for valves made of SS321. Only the forging grade has been seen. CF8C is a cast version of 347, per ASTM A351.
There is no corresponding casting for 321; 347 corresponds to CF8C
Why do they need to correspond to each other? I still haven’t really understood these codes: L
Let me explain: 321 contains Ti, 347 contains Nb, and CF8C is indeed a casting of 347 material. So why are there no castings for material 321? The reason is that 321 castings are difficult to obtain; 321 contains Ti, and titanium is highly susceptible to oxidation. Typical foundries lack the appropriate means to prevent titanium from oxidizing during casting; therefore, ASTM material standards do not include any casting grades for this material at all.
I think I can check the relevant manual; it must be there