Hi Dude & Dudettes,
I am designing a vessel, with I.D. of 1600mm and 4000 length.
the required shell thickness is 28mm , and i need to provide a 20" manway. because of the small ID off the vessel, i need to use long weld neck nozzle for the 20" manway to minimize repad dia. 20" Long weld neck nozzle has 40mm wall thickness.
My question is, Is PWHT required if i am welding the 40mm thick nozzle to shell which is 28mm. I am confused as the 40mm thick nozzle neck is more that the code's 38mm. Some say it is not required as the code only takes into account the thickness of the welded part i.e. the shell wall - which is less that 38mm, therefore no PWHT.
Another thing is, i am using the longweld neck which is supposed to be a self reinforcing nozzle, but according to PV elite i still need repads.. I have already designed internal projection to the limit yet repads are still required. Am i missing something here?
I hope i have made my case clear. Plz do offer your views. Thx in advance.
Regards,
Milk Boy