Welding Procedure Specification - Selection on welding methods

[AlfaMike5886]

Hi all,
I am rather new to welding procedure specifications.
I have gone through BPVC section IX, and i understand it is playing pivotal role in creating WPS. i still have questions that may sound naïve to person experienced in WPS. They are as follows...

1)How to decide the welding process? GTAW, Gas welding, or electric arc welding? ->
in section IX QW-400 tables are given for essential and non essential variable for each type of welding methods. But i do not know on what basis one selects arc welding or gas welding. Who decides which type of welding methods are to be used for certain joints. What are the criteria?

 

[LittleInch]

The welding engineer.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[weldstan]

Alloy to be welded, available welding equipment, locations of welding and COST, COST, COST. Diito LittleInch above.

 

[EdStainless]

And cost has a lot more to it than the speed of the weld.
The weld prep, consumables and the QA are very important.
And don't be surprised to see WPS with additional essential variables listed.
The ones in the table are Code required minimums.

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P.E. Metallurgy, consulting work welcomed

 

[FacEngrPE]

The total amount of welding also matters, as the weld volume needs to pay for the equipment. again cost.