Inox 304L fillet welds ...Backing gas

[cirieh]

Dear all,
situation:
[ul]
[li]earthing lugs to be welded on pipe[/li]
[li]Pipe of 304L (LNG cryogenic line) (thickness min.3.73, max 12.7mm)[/li]
[li]earthing lugs of 304L (taken from pipe of project material) thickness 5.54mm[/li]
[li]Line compleated.[/li]
[/ul]

Applicable code ASME B31.3 & IX

Our WPS cover butt weld with GTAW and backing gas.
This WPS is also used to weld atthachment over the pipe.
Our client don't have mentioned any discoloration criteria.

Can I weld earthing lugs without backing gas?
Do you have any reference?

 

[Guest102023]

Are you concerned about discolouration (heat tint) on the pipe inside surface?
At 3.7 mm thick that is a distinct possibility, one which probably needs to be addressed if corrosion resistance cannot be compromised.

"If you don't have time to do the job right the first time, when are you going to find time to repair it?"