How to qualify welders to welding tubular spiral.

[Thuhuongengineer]

Hi friends,
i have tubular OD=1100 mm, welding spiral (sloping 40 degree between axis tubular) accoding to ASME IX. I dont know position of this joint: 5G or 3G.. Pls give me advice.

 

[stanweld]

Qualify your welders in the 6G position.

 

[Thuhuongengineer]

I know 6G can cover all position but i want to know exactly this joint (sloping 40 degree between axis tubular) is 3G or 5G follow QW 461- ASME IX

 

[gtaw]

Are your welders welding the spiral seam in the shop where the pipe is rolled as they weld it or are they welding the spiral in "all" positions because the pipe is not rolled, but is stationary during welding?

Best regards - Al

 

[Thuhuongengineer]

Hi GTAW,
Welders weld the spiral seam in site. Tubular were fixed horizontal.

 

[gtaw]

You could qualify the welders in both the 2G and 5G positions to cover the positions encountered when welding the spiral pipe.

I do have another question. The spiral is usually welded by the manufacturer using mechanized or automatic welding machines. How is it that your welders are welding the spiral on-site? I can understand the welders welding the girth joint or welding a branch, but under what circumstance are they be welding the spiral?

Best regards - Al

 

[stanweld]

You can also qualify the welders on plate in the 2G, 3G and 4G positions to qualify all positions.

 

[gtaw]

For pipe?

Best regards - Al

 

[DekDee]

Plate and pipe over 24" Al - see Table QW 461.9,
Cheers,
DD

 

[stanweld]

Also the welders may qualify in your Special Position per QW-303.3.