Additional welding after hydrostatic test

[Sang-Won-Oh]

Hello,

I have a question.

If weld the platform clip to the nozzle reinforcing pad after the hydrostatic test, should I do the re-test?

And is there anything in the ASME code related to that article?

 

[IFRs]

What standard is this vessel designed to?
What material is the repad?

 

[LittleInch]

If its not direct to the vessel or the pipe, then it doesn't count as a direct weld impacting the pressure containment envelope which has been tested.

But the devil is in the detail you haven't supplied, like a drawing or sketch.

 

[Sang-Won-Oh]

What standard is this vessel designed to?
What material is the repad?

ASME SEC. VIII DIV.1 2023 ED. CODE and material is A516-70, horizontal vessel type.

 

[LittleInch]

Attach a drawing or sketch so that we can see what you are talking about.

 

[Christine74]

I think it would be helpful if we knew if you are the vessel fabricator or if you are the end user of the vessel, but in either case ASME Section VIII is a design/construction code so it's applicability ends the minute the Authorized Inspector (AI) signs the U-1 Manufacturer's Data Report. Any mechanical changes to the vessel made thereafter are typically done in accordance with the National Board Inspection Code NB-23.

Typically the AI would classify what you are proposing as a "Repair" and would not require you to repeat the hydrotest.


-Christine

 

[LittleInch]

The question is whether the "nozzle reinforcing pad" counts as part of the PV itself or is regarded as outside of the pressure envelope.

 

[Christine74]

A nozzle reinforcing pad is a pressure-containing part so welding on it would be considered to be welding to the vessel pressure boundary, but sometimes pads (not reinforcing pads) are installed on vessels in the fab shop prior to hydrotesting to allow non-Code field welds to be made to the vessel (e.g. for attaching pipe supports, platform clips, etc.).


-Christine