ASME IX qualification for Section VIII Div 1 non-code weld SA-240 316L vessel

[norms943]

Appreciate any help on this.
The question is about some internal bracketry, which is not attached/welded to the pressure boundary.
Bracket material is also SA-240 316L, which during operation may see temperature of 600°F - 700°F.
Is this temperature to be considered as essential for procedure qualification, or PQR to be tested "as-welded".

In general, where do we draw the line before we call something a post weld heat treatment fof 300 grade stainless steel?

Again, thanks for any help.

 

[stanweld]

The PQR will be tested "as-welded". Corrosion may be of particular concern and you may also want to select a pertinent corrosion test for qualification. It's strictly up to you.

 

[metengr]

Post weld heat treatment according to Code requirements is well above your service temperature for austenitic stainless steel material. Normally, post weld heat treatment is neither required nor prohibited for austenitic, nonhardenable base materials.

 

[norms943]

Thank you stanweld and metengr for your replies. It was the statements from Section IX that made this a grey area for me.
407.1(b)
(1)No PWHT
(2) PWHT within a specified temperature range.
One could believe from this that any additional heating after welding could be thought to be a PWHT, since no specific temperature is given as a so called line in the sand of when a temperature is considered PWHT.

metengr, when you say "Post weld heat treatment according to Code requirements is well above your service temperature" could you please provide the reference paragraph in which this is discussed?

Thanks again to both for responding.

 

[norms943]

Not to be a bother but, is this my answer?
Section VIII, UHA-105 then to Appendix A, A-350 and A-360 of Section II part D.
In other words, (other than the obvious corrosion resistance loss) embrittlement would be the concern, and that concern becomes a reality around 1100°F?

 

[jwhit]

In the case of 316 or 316L the post weld heat treatment is actually a full solution anneal intended to restore corrosion resistance by eliminating precipitated carbides and sigma phase(highly unlikely) that may have formed by the act of welding. A solution anneal is done somewhere above 1900f. There is very little direct influence on mechanical properties except in the case of work hardened material by a solution anneal. In your case, using the part as welded at the service temperature you specified would not require you to account for the service temperature in the procedure. As someone else mentioned, the embrittling sigma phase starts to form somewhere around 1100f to around 1800f, it is a long term process. At 800f carbides may start to precipitate, which can influence intergranular corrosion properties.