PWHT on lifting lug welds
PWHT on lifting lug welds
(OP)
I am working on lifting study for replacing an existing vessel.
The vessel is not designed per ASME code, so there is no PWHT requirement even though the shell is P4 materials. The operation temperature will be nearly 1000F. The shell thickness is 3/4". When we weld the trunnions on the shell, I notice that we need PWHT on those welds. The client wants exempt the PWHT.
Considering the lug is a one-time useing part and the vessel is not designed per ASME Code.
Is there some other standard / code can be used to exempt the PWHT?
Any advice will be appreciated.
The vessel is not designed per ASME code, so there is no PWHT requirement even though the shell is P4 materials. The operation temperature will be nearly 1000F. The shell thickness is 3/4". When we weld the trunnions on the shell, I notice that we need PWHT on those welds. The client wants exempt the PWHT.
Considering the lug is a one-time useing part and the vessel is not designed per ASME Code.
Is there some other standard / code can be used to exempt the PWHT?
Any advice will be appreciated.





RE: PWHT on lifting lug welds
If you want to exempt PWHT for P-No 4 material for this type of application, you have two choices (maybe 3);
1. temper bead in accordance with Alternative Weld Method 4 as indicated in the National Board Inspection Code (NBIC),
2. Local PWHT per the NBIC,
3. or let your customer dictate, and make sure you have NO liability in the event a problem develops.
This web site might help with the temper bead method;
http://www.wtia.com.au/tgn.html