Compensation Pads on Lethal Service Vessels

[johnnymist2003]

Hi all,

does ASME Section VIII, Div.1 probibit the use of compensation pads for nozzle reinforcement on vessels which are considered to be in lethal / dangerous service ? If so, please direct me to the relevant paragraph.

Thanks.
John

 

[prex]

Can't find that limitation: you are only required to full penetration weld the nozzle, and this can be done through the compensation pad.
The rules are in UW-2(a).

prex

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[VeryPicky]

John

What is your position in this fabrication? Are you an owner or manufacturer?

There is no such limitation in the ASME VIII Div 1 code. I support prex cat D welds shall be full penetration.
I don't know the specifics of your vessel so you have to read the whole of UW-2. It gives requirements pertaining to service. The owner is responsible to identify lethal service if applicable.

Your question may be related to RT requirements of the UW-2. Some users may require a special nozzle configuration to facilitate the NDE. UW-2 describes an acceptable procedure for nozzle NDE.

Putting Human Factor Back in Engineering

 

[johnnymist2003]

Hi all,

thank you very much for the valued information. This confirms my opinion - that Cat D welds must be full pen and that comp pads may be used. We are a manufacturer and are in a debate wrt money (as usual!!). I am pretty well versed in the requirements of the Code (been around a while) and I was surprised to hear the contractors argument. The contractor will not pay additional fees for changes because in their opinion the Code prohibits the use of comp pads on lethal service vessels, I have been arguing the point.
Regards.
John

 

[ReMan]

Check out Interpretation VIII-1-98-113; it explicitly answers your question.