ASME Code Interpretation

[quantrus]

I have some question about hydrotest requirements on an ASME pressure vessel. A vessel recently built to Section VIII, Div 1 has heads attached to the shell with flanges. There is a fixed flange on the shell and a loose flange on the head that sits behind a welded lap ring. The assembled vessel was inspected, hydrotested, certified, installled at site (hydrotested a second time on site) and placed in service. During a turnaround some months later it was opened for cleaning. It was observed that the lap rings on both heads were somewhat distorted (presumably during the hydrotest). Both lap rings were rotated such that a dial guage reads the outer diameter to be higher than the inner diameter on the face (from 1/32" to as much as 1/16" across the 1 1/2" face). Three questions: 1) Does the lap ring distortion on hydro effect the certification? 2) Must the lap rings be remachined (neither has leaked)? 3) if lap rings are remachined will another hydrotest be required?

 

[cloa]

You shouldn't double post- you can post with a link to your original post.

 

[metengr]

1) Does the lap ring distortion on hydro effect the certification? 2) Must the lap rings be remachined (neither has leaked)? 3) if lap rings are remachined will another hydrotest be required?

1) No

2). No

3) No, this is outside of ASME B&PV Code because this is an in-service vessel and no weld repair is required.

 

[quantrus]

Thanks for your comments.