Thickess selection for welder while welding a nozzle with R.F pad

[PRAVEEN1709]

Hi Gents,
I have a 18" nozzle to be welded in a pressure vessel. Nozzle contains Reinforcement pad. While assigning a welder whether i need to consider both shell thickness and R.F pad thickness together as a same joint or i need to consider it as a separate joint. Is there any code reference available?
Note: For nozzle groove design is inside bevel which means welding will be done from inside of the vessel, after completing welding from inside R.F pad will be welded from outside.

 

[david339933]

Separate welds. Shell to nozzle weld should be ground/gouged and filled for complete pen. Then this will be backing for the pad groove weld.
Governing thickness and MDMT of each weld must be determined per UCS-66(a)(1)(4)

 

[PRAVEEN1709]

Mr.David,
Thanks for your feedback. It was really helpful.

 

[MUHAMMAD FAHAD RANA]

It depends on Welder Qualification with keeping all essential variables which applies in your case.

I reckon , you have welder with multi qualifications (GTAW+SMAW) for Pipe in 6G Position such a way SMAW deposits greater than 13mm with as least 3 layers which results him to qualify Maximum to be weld. (Selection of Pipe greater than 73mm with higher schedule to meet SMAW deposits atleast 13mm).

SO in your case: For Nozzle to Shell you welder weld with WPS (GTAW+SMAW) where GTAW without backing but SMAW with weld metal backing and meeting all essential variables of GTAW & SMAW as per QW-353.

and same welder can be utilize to weld with RF Pad to Nozzle with SMAW process with Weld Metal Backing.

I hope it clear if found any difficulty , ask question.



Fahad