ASTM materials for non pressure parts

[fabtank]

Can materials certified to ASTM specification be used for a non pressure part welded to a pressure vessel fabricated under Section VIII Division 1?
Can ASTM A572-50 be used for a bracket?
Can a wide-flange beam be welded directly to a vessel?

 

[metengr]

Yes. All you need to do is to demonstrate weldability of non-pressure part material - qualify an WPS per Section IX.

 

[jte]

As metengr said, it must be a weldable material. Section VIII-1 reference would be UG-4(b) which pushes you to UW-5(b), for which sub paragraph (1) allows qualification of a WPS per IX as proof of "weldability".

Now at the end of the day engineering jugement comes in to play. As a rule, I would recommend using SA grade materials for all welded parts. For minor parts such as nameplate brackets and instrumentation conduit supports (we don't need no stinkin' insturments!), I'd would not object. Would I support welding a wide flange beam directly to a vessel? Probably not, but that means that in some circumstances I might support that idea: I would not support welding a WF beam directly to the shell if the beam is a bed support beam carrying a substantial load and transferring it to the shell. Too many issues to get into here. On the othe hand, I've seen plenty of vessels, generally small to medium size, which use WF legs instead of skirts for support. These legs are often coped to align with the head/shell and are welded to both. I've no complaint with this type of arrangement - I just don't see these frequently in my business.