Cyclic Vessel - Fillet Welded Nozzles

[roca]

I have been given an air receiver vessel detail on a package which has been accepted by the project.
The vessel operates under cyclic conditions.
Code = ASME VIII Div 1
Design pressure 33barg @ 120°C.
Vessel = 800mm ID x 18mm wall thickness
The fabricator – for whatever reason, has applied 6mm fillet welds to 3 nozzles (including the inlet and outlet nozzles) and full penetration welds to the remaining nozzles.
All nozzles are 2” NB.
The project pressure vessel spec which was not issued with the purchase order would not have accepted fillet welded nozzles.
My opinion is that the fillet weld detail is not acceptable and if necessary calculations should be performed to verify the design or alternatively nozzles to be cut out and welded in using full penetration welds
The fabricator states he is in accordance with ASME VIII
Any thoughts on this………

 

[jte]

What calculations has your fabricator provided to indicate that their design is in compliance with UG-22(e)?

Your concern for the adequacy of the fillet welded nozzles is reasonable. However, given the small diameter, they may actually pass. Most folks would use a Div. 2 approach for the evaluation, though technically U-2(g) allows any reasonable method.

Ask your fabricator for his UG-22(e) calcs for the nozzles and post a photo of the look on his face!

jt

 

[roca]

Thanks
Will check for the cyclic load calcs.
Even though the Code allows fillet welds I never accept them unless the vessel is an atmospheric vessel or a storage tank.
All nozzles should be full pen welded.