MACHINING AFTER HYDROTEST

[PEHasan]

Hi all!

Fabrication of 36" Pressure Vessel has been completed. This vessel has a support ring that is welded inside the vessel shell. This ring will support the tube plate.

Vessel is about to be hydrotested.

Just now we found out that we have to modify the support ring.

Can we machine support ring after the hydrotest of vessel?

If we postpone the hydrotest, it could lead to delays.

Regards,

PEHasan.

 

[PEHasan]

This vessel is an ASME Code "U" Stamp vessel.

 

[PEHasan]

This vessel is an ASME Code "U" Stamp vessel.

PEHasan.

 

[metengr]

Check with your Authorized Inspector (AI). Machining performed after the hydrotest is permissible. However, you had better be sure that the machined support ring is acceptable for service by design calcs. If not, weld repair could be required and this could be done as a repair in the field. Again, check with your AI.

 

[Tenoa]

It is not likely that this will be allowed, especially if you have had any PWHT performed!

 

[TLIU]

Like Metengr said:
1. Contact with your AI.
2. Check your calculation.
3. Do a repair per ASME code.

 

[pvesseleng]

if this ring enough to satisfy calculation requirements after machining, there is no problem. but becareful for pressure retaining part.