nozzle intersect circ weld question
nozzle intersect circ weld question
(OP)
We are looking at purchasing a vessel which has been constructed to an italian RINA code approx 20 years old.
We have found that it has a 2" nozzle which intersects the main circ weld from rolling to dished end.
Rina were not bothered but i am wondering where we would stand with ASME or even just good working practise ?
maybe someone can enlighten me? Thanks. Neville
We have found that it has a 2" nozzle which intersects the main circ weld from rolling to dished end.
Rina were not bothered but i am wondering where we would stand with ASME or even just good working practise ?
maybe someone can enlighten me? Thanks. Neville





RE: nozzle intersect circ weld question
I don't see this as a problem of design. (see UW-14 in Section VIII, Div 1, Part UW of ASME B&PV code). If you have not considered this already, make sure you have performed your due diligence in terms of obtaining the prior operating history, maintenance and repair records of this vessel. In addition, you might want to perform your own RT, UT and MT inspections of the vessel welds and appurtances.
RE: nozzle intersect circ weld question
I agree with metengr. While it is desireable and good practice to avoid putting nozzles through welds, sometimes it has to be done. Provided that the due diligence is provided it shouldn't be an issue. With a used vessel, I'd consider calling for a few RT's of the area around the offending nozzle and use UW-14 as a guideline for an acceptance criteria. I'd be a bit more concerned if it was a longitudinal seam, but either way, the answer's the same.
jt
RE: nozzle intersect circ weld question
RE: nozzle intersect circ weld question
Care to let us know what part of VIII-1 or VIII-2 supports your statement about openings through the knuckle?
jt
RE: nozzle intersect circ weld question
RE: nozzle intersect circ weld question
RE: nozzle intersect circ weld question
Knuckles under repeated cyclic loads are prone to cracks and various P.V. literatures recount leaks in these highly stressed areas. NBIC forbids repairs in knuckles but with trepidation allows such repair in well equipped shops.
With this background, this is the reason that I stated to stay awy from knuckles.