overlapped welding in pressure vessel 1

[Aaziz21]

Dear all ,

I would you like to ask about the below photo the welding of nozzle is overlapped with longitudinal weld of pressure vessel is it accepted if the pressure vessel was alliterated according to ASME VIII.

Thanks in advance

 

[JStephen]

I don't remember right offhand what the requirements are, but there are provisions for nozzles to go in seams- the different factors used in calculating reinforcement are adjusted accordingly.

Normally, this would be avoided as good practice, but if installing central nozzles in large heads, you're not going to have much choice.

 

[r6155]

No problem if longitudinal weld is RT 100%. See more in UW-14
Regards
r6155

 

[jte]

As stated above, if this is a Section VIII Div. 1 vessel then UW-14 covers this. In my company's engineering standards this would violate a "should" clause as it is something to better avoided but in some cases unavoidable. I'd argue that it is most likely that this could have been avoided quite simply by shifting the nozzle up or down and using internal piping if the precise elevation of the connection is critical. Given that this is a small hillside nozzle, it may be for a level bridle and in this case the adjustment can easily be made with piping.

 

[bpv66]

UW-14 states that any opening that meets the reinforcement requirements of UG-37 or UG-39 may be located in a welded joint. So, RT may not be required on this longitudinal seam.

However, as others have posted, this should be avoided if possible.