Flare Bevel Groove Weld Effective Size

[LowLax]

Why (according to AISC 13th ed) is the effective size of a flare groove weld 5/16R with SMAW and 5/8R with GMAW?

Seems like a big difference. There's obviously something I don't understand about the difference in welding processes.

 

[gtaw]

It may be due to the higher currents used with the GMAW using spray mode transfer. The higher current typically results in greater joint penetration.

I tend to be conservative and stay with the limitations provided by AWS D1.1.

If you have any concerns with the increased weld size permitted by AISC, make a couple of samples that replicate the joint detail you are considering (the diameter of the round is important). If the macroetches of the samples suport the increased weld size as permitted by AISC, make sure your welders are using the same welding parameters as those used used to weld the samples.



Best regards - Al