I've run into a problem with TIG welding of 316L ss. I've had a metallurgical test run on the material. The carbon content is .004, other elements are withing guidelines for 316L. We have found .2285 cobalt and .049 vanadium elements included in the test. We are TIG welding 316L pipe with standard metallurgical characteristics to weld neck flanges having the elements given above. The welders are having trouble breaking down the wall of the WN flange. They are overcoming this, but x-ray results are showing lack of fusion and penetration problems in the welds. Does anyone know what would cause this. One welder in particular has been welding ss with success rates in x-ray above 98% until this project. Not alll welds are failing b31.3 examination, but the there is an unusually high amount. Commenst made by the radiograpgher is that the welds look great except for lack of fusion and as stated some lack of penetration in the root.

Dear Sir, I really need your help. I have one assignment about welding technology for stainsless steel 17-4. Welding with same steel 17-4. 1. What is the Heat Zone for the process? 2. What is the normal problems that always occur during the process? 3. What is the industrial machine name that can be use to weld the steel? Mostly the steel is use to built Control & Sensors parts. Any one who knows the answers.. i would really2 appreciate! thank you so much.

It's bit difficult to guess the reasons. However, exploring every possible reasons may help 1. Whether Argon urging was done ? 2. What is the thickness difference between pipe & neck of WNRF flanges. In case of insufficient purging, problem in root passes may occur. Also, though unlikely in this case, a huge difference in thickness results in differential cooling rates & weld drops may solidifiy before proper fusion. This is more common in CS/AS where thermal conductivity is high. 'Hope this helps. Regards PLC