B31.3 High Pressure applications; Impact Testing

By jon20013 (*****)

Date 02-13-2008 05:25

I'm curious, for anyone with ASME B31.3 High Pressure experiences, why do you think the code would require impact testing for "all" materials on a unilateral basis? I mean, certainly we all understand why impacts are required in the first place but if we have austenitic or nickel based / filler metal combinations which specs say are good stuff down to near cryogenic levels, what reason? js55, this is already in your personal mail inbox! ;-)

By js55

Date 02-13-2008 14:56

I have to say jon, I do not find anything in Chapter IX that gets you away from your dilemma.
And to test alloys such as 625 or 6Mo at moderate temps is problematic to say the least, not to mention that in my opinion it tells you nothing.
And this would be another instance of the material being better than the testing machine (even a 240 ft/lb'er). You probably won't even break the Charpy. And I don't even see anywhere that allows you to go to Table 323.2.2 and allow tensile elongation or notched tensiles as a substitute for your nickels.
the only reference to 323 Ifound was Table 323.3.4. That doesn't help. and Table K-1 doesn't provide temp limits in the manner of Table A-1 for impact test evaluation.
I see you're bringin in some heavy hitters (no better high alloy or 31.3 guys I can think of). I certainly anxiously await their consensus on this. Please, and I mean that, keep us informed. I'm gonna keep lookin.

By jon20013 (*****)

Date 02-14-2008 01:02

Will keep you in the loop, have been fortunate that all have responded and also been given some historical insights. Committee is receptive and since I'll be testing everything here anyway will be able to eventually support opinions with empirical data however a few of those heavy hitters suggested beginning with VIII, Div. 2 as a fundamental start point for consideration. A wise beginning in my opinion.