Non welded stiffening ring on a U stamped pressure

[johcatrac]

We have an existing pressure vessel to which we are attaching external stiffening ring. The attachment is not by welding or brazing but as a clamp. i.e. a complete O clamp is being used here. The purpose is to change the modal response of the vessel and also to act as a support for a motor that will be mounted on the vessel. The vessel is part of a skid assembly.

Questions
1. Is a non welded external ring permitted?
2. Will the 'U' stamp be affected?
3. Will this be classified as repair/alteration and thereby use NBIC?

Any input would be appreciated.

 

[SnTMan]

johcatrac, 1, permitted by whom? Owner? Jurisdiction? I'd guess it is permitted.
2, not likely, U-Stamp pertains to new construction only.
3, I'd think not, but would check with the AI / jurisdiction.

Regards,

Mike

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