B31 Ferritic Steels, Austenitic SS, and Other Ductile Metals 1

[Ben4piping]

I have questions pertaining to the metal groups noted in ASME B31.3, Table 304.1.1 Values of Coefficient Y?:

Ferritic steels: Are they only the 400 series SS, duplex, and super duplex austenitic-ferritic SS?

Austenitic stainless steels: Are they 300 series SS and super SS (904L SS)?

Other ductile metals: Are they carbon steels, alloy carbon steels, and non-ferrous metals (Al, Cu, Sn, Ni, Ti, Zr)?

I may have been confusing ferritic with ferrous.

I am aware that increasing the Y value increases allowable pressure.

Thanks, Ben Nottingham

 

[StevenHPerry]

Ferritic and austenitic refer to the phase of steel. Ferrous refers to the composition.

Take a look at B31.1 if you can.

B31.1's appendix A is written a bit differently, but it clearly states that
all carbon steels are ferritic
all low and intermediate alloys are ferritic
stainless steels are grouped in table A-3 by their phase.

Nickel, copper, etc etc alloys are given a y-value in the general notes of each appendix A table.

Otherwise, look at the material standard for some clues. ASTM A335 for example is for "Seamless Ferritic Alloy-Steel Pipe."

- Steve Perry

http://www.linkedin.com/in/stevenhperry

This post is designed to provide accurate and authoritative information in regard to the subject matter covered. It is offered with the understanding that the author is not engaged in rendering engineering or other professional service. If you need help, get help, and PAY FOR IT.

 

[Ben4piping]

Hi Steve,
Thank you very much. You answered all of my questions. Those "Notes" are the fine print I was needing to see. I do have B31.1, and missed looking up the notes section for non-ferrous materials, etc.

Best Regards, Ben Nottingham