Welding SA355-P22 1

[GemmellG]

Installing OTSG having issues with welding SA355-P22 Inter-connecting tubing. Repair rate is 60% Welders are experienced & had no issues with pre-job test. Welds are purge with argon pr-heat is 390F. Weld wire specification has an X Factor of below 10 actual 9.6 & J Factor of below 100 actual 99. Would the low X & J factor have any thing to do with the repairs we are experiencing. Defect types are lack of fuision porosity & internal concavity (Suck Back). It is my understanding the J Factor is for base metal & not intended for the weld wire could this be an issue.

 

[metengr]

The lack of fusion and suck back are really welder performance issues and have nothing to do with the residual elements regarding temper embitterment in weld or base materials. Assuming proper low hydrogen weld filler metal, check the shielding gas purity, make sure the weld joints are clean on the ID and OD before welding, and ensure proper fit-up at the weld joint.

In my years of working around power generation equipment contractor welders that have passed bench tests and then work in the field under adverse conditions can result in the problems you are experiencing. You need A team welders.

 

[metengr]

GemmellG;
The information below may help you to get through this.

http://bbssystem.com/manuals/Aluminum-Welding/35679_11.pdf