ASME III - Appendix U

[chti]

Hi,

For an example,We have to manufacture a pump according to ASME III Class 1 , appendix U is required by customer.
In appendix U,in paragraph U-1312 for permitted material,it is required material according to Table U-1610-1 of this Appendix and materials listed in Section II,Part D, Table 2A. My question is about material cat 3 and 4.
I understand that material could be supplied according ASTM code(tableU 1610), but when there is no reference to a grade,we have to choice a matérial according to section II,Part D, Table 2A,which is only ASME references.By example, an impeller grade CF3M,no referenced in table U1610, but in SA 351, but there is no reference to A743, which is for non pressure part! It is the same case for a shaft, no reference in table U for AISI 316L, and we have to choice by example,in SA 479 Gr 316L!ASME specification are generally equivalent to ASTM specification,what are the difference if we have SA351CF3M and A351CF3M? This paragraph, is difficult to understand for me and not very clear !
Thank tou for your help.

 

[cloa]

Wrong forum- you meant ASME forum

 

[trottiey]

I think this is a good forum for this question. ASME III is nuclear.

If there's no reference to A743, then you can't use it. There might be a code case that allows it, or you could try to bring one forward. Or you could just use SA-351 CF3M. The code does limit what materials you're allowed to use.

What's wrong with using SA-479 316L bar?

Most ASME specifications are identical to ASTM specifications, and state as much at the top. But ASME does make some changes to a few of them. Also, when you buy ASME materials for Section III use, I imagine you will need to mee NCA-3800? But I haven't worked with pumps myself.