SA36 Attachments in Low Temp 1

[weed78]

A carbon steel vessel is made to Sect. VIII Div. I with MDMT -50°F.
The vessel has external attachments that are subjected to loads resulting in stresses on the shell or head.
Can such load bearing attachments be made from SA36 or even SA106B (not normalized nor impact tested), or must they be treated like all other pressure components such as nozzles?
Thank you

 

[JoeTank]

If these items are carring loads, I recommend that they also be of material with adequate toughness at the MDMT. The attacjhment welds are Code welds. I believe that ASME VIII may only require that the attached material be of weldable quality material, but I think that is woefully inadequate.

Joe Tank

 

[metengr]

If these attachments are welded to the vessel, they shall be evaluated for impact testing in accordance with UCS-66 requirements. Specifically, review UCS-66 (a), in the 2004 Edition/2006 Addendum note....

"Components such as shells, heads, nozzles, manways, reinforcement pads, flanges, tubesheets, flat cover plates, backing strips which remain in place AND ATTACHMENTS WHICH ARE ESENTIAL TO THE STRUCTURAL INTEGRITY OF THE VESSEL WHEN WELDED TO PRESSURE RETAINING COMPONENTS SHALL BE TTREATED AS SEPARATE COMPONENTS. EACH COMPONENT SHALL BE EVALUATED FOR IMPACT TEST REQUIREMENTS BASED ON ITS MATERIAL CLASSIFICATION THICKNESS.....

So, read the above carefully and evaluate for impact test requirements.

 

[JoeTank]

metengr,
Another mighty contribution. A star to you.

Joe Tank