boodrow

Porosity can come from a number of places. Yes the typical culprit is from the base metal not being properly cleaned but, it can also come from worn out equipment. Check the "power cable" of your rig as well as your torch. I won't let any of the welders on my projects use the old flex neck torch heads that look like a crinkle cut French Fry they were made by weld craft and are pretty much obsolete. What happens is that the argon dries out the rubber and small cracks form that allow oxygen to be sucked up in along with the argon, kind of a venturi effect. Also it's a typical practice to use an oxygen regulator for argon in the field to increase the argon pressure at the gas shield lens I did it for years but remember sometimes to much of a good thing is a bad thing. To answer your original question, yes SS wire will cover up porosity. But like has been stated in the post before, if it takes this to fix your porosity issues you might want to rethink your career choice. The welding world is a very small one and it's a hell of a lot harder to rebuild your integrity than it is to build a good one in the first place. As a QC manager I'd rather a welder tell me that he was having problems (so that I can help them) than for me to catch one cheating me, more importantly cheating them self. Boiler Code is actually Asme Section 1, Asme Section XI is used to set welding procedures and to test welders and are two totally different codes with two totally different purposes.

Yes, it's done to prevent porosity from forming on the sides of a tube section (typically where the membrane comes together). You can do it using the SMAW or GTAW welding processes. I have used this technique for welding 180* bends (candy cane sections), in the water wall, penthouse and crossover sections of boilers. It can be an extremely beneficial method to learn. Basically what happens is when your welding partner comes up as far as he can go you just hold your electrode or torch up in the bevel of the weld and when he gets close enough the arc transfers from him to you. You never break the arc thus no start stop area in the jammed up side of the weld and therefore no porosity. It takes a little getting used to but it'll make you a better welder for knowing how to do it. I have worked for a several double time company's as a welder and as a QA/QC manager it's just one of the many tricks that you learn with 20 years under a hood.