U1 head weld efficiency

[mgad11]

If I have U1 for that does not state the weld efficiency of the head, can I use the shell cirum weld efficiency ??

this is regarding a pressure vessel that is already in service.

The head is hemispherical and the shell citrum is type 1 with eff. of 0.85

 

[david339933]

For hemispherical heads the efficiency for thickness calculations includes the head to shell joint....therefore E=0.85.

 

[FormerAIS]

If there is a weld seam in the head, it is very likely that the efficiency is not 0.85.

Quality is not an act, it is a habit - Aristotle

 

[david339933]

Finally had my coffee....AIS is correct, this assumes seamless head.

 

[SnTMan]

mgad11, I'd say if the head is seamless and you know the head to shell seam was spot RT'd independent of the cylinder long seam you may use 0.85, if not you must use 0.7. See UG-32(b), definition of E.

Do you not have the vessel calculations, weld map, etc. available to confirm?

Regards,

Mike



The problem with sloppy work is that the supply FAR EXCEEDS the demand

 

[oknow]

The U-1 form does not have a field for the Cat A head weld. I would suggest to indicate in the remarks section. The U-1A does have a field for the Cat A weld with the NDE and E applied. If the MDR's are completed correctly one should be able to draw it out. There continues to be issues on completing the MDR's correctly.

 

[RAJPT89]

If you can let us know the purpose of your question, we might be able to answer properly.

Thanks,

Rajput