PWHT Sect. VIII Div. I

[glrsbmiqc]

I need to attach some temporary lugs (push-pull) to a section of the vessel that has been heat treated. The lugs will be of P-1 material and attached by 3/8" fillet weld, the shell is P-1 material with a 1" thickness.
I don't see anything in sect. VIII that gives me a out to having to PWHT these areas. Am I missing something?

 

[CodeRef]

What is your governing nominal thickness as defined in UW-40(f)? REF: UCS-56(a)

Is postweld heat treatment a service requirement as set forth in UCS-68? REF: UCS-56(a)

What does your AI say?


FAQ731-376

 

[Sharik]

ASME Section VIII, Div. 1, 2007 (2008 Addenda), Table UCS-56 for P1 materials,

"Notes:
(2)(c)for welded joints of all thickness if required b UW-2, except postweld heat treatment is not mandatory under the conditions specified below:

(3) for groove welds not over 1/2" (13mm) in size or fillet welds with a throat thickness of 1/2" (13mm) or less used for attaching nonpressure parts to pressure parts provided preheat to aminimum temperature of 200F (95C) is applied when the thickness of the pressure part exceeds 1 1/4" (32mm)."

I would recommend still preheating the base metal even though the thickness you indicate is only 1".

 

[glrsbmiqc]

Sorry for the typing error, the shell material is P-4 (SA387 Gr.11).

 

[CodeRef]

No, you are not missing anything. The fillets attaching the lugs are strength welds and PWHT is a requirement because you are attaching lugs to a shell made of plate, the exemptions provided in Table UCS-56 Note 2, for P-4 materials applies to pipe or tube materials.
I have not looked/searched for Code Cases (alternatives), but I do not expect there to be any....

FAQ731-376

 

[Sharik]

Big typo!!! For P4 materials, you are hooped and PWHT is required for welding nonpressure attachments to the shell.

 

[GenB]

you are probably okay if your AI authorizes it.
Show the AI that you will meet the pre-heat requirements.
some inspectors will not help you but the Code allows it.

 

[AIOR]

Hi,

It looks like the only option available is a local PWHT for your attachment welds per UW-40.

Thanks.