Welding Tips and Tricks

Hi all! Being a student in NDT I was going through this youtube video and have a doubt regarding the welding process they're using. At 3:32,3:42 and 6:59 he is using Mig welding, i guess...But, at 5:55 he's using Tig maybe? can anyone correct me..
Thanks for your reply

[youtube]https://www.youtube.com/watch?v=SPX7_jJtTGQ[/youtube]

Can't say for sure. Could be some kind of wire feed process or maybe even stick welding. But I can't see if he is holding a MIG gun or a rod holder. The fact that you see sparks (TIG does not often spark unless you make a mistake) and the fact that I don't see his other hand making rod feeding movements make suspect its not TIG. Economically it makes no sense to use TIG in this application. A wire feed process of some kind (probably not MIG but maybe gas shielded flux core, or metal core wire) would make the most sense. You get highly quality welds equal in characteristics to a 7018 stick weld (charpy notch ratings, low diffusible hydrogen levels etc.) with a much higher level of productivity. The deposition rates for something like a metal core wire can approach 15-20 lbs per hour.

the miller wire feeder gives it away. plus the smoke and noise.
its most certainly mig, most likely using dual shield or metal core wire.

It is probably MIG. The noise, spatter gives it away