E 7016 single side root pass

By Kix

Date 11-02-2007 12:50

Yes it is possible. We run the root in on on A/C polarity. You wouldn't happen to be practicing for a welding competition would you? I've been working with the U.S. representitive for the World Skills Competition in Japan and one of the pipe tests could be an open root with a 7016 KOBELCO rod and he has it down pretty slick. I feel another Gold medal for the U.S.A. coming on.

By dbigkahunna (****)

Date 11-02-2007 13:49

Yes, but if you are welding on pipe, and the procedure calls for DC, better keep it on DC! I have never seen a PQR where the procedure was ran with AC and that is and essental variable. THe critical thing on open root with low hydrogen is travle speed, heat and root opening. You want just enough heat to melt the bevel edges, the root opening needs to be the width of the welding rod and the travel speed needs to be ..... This is not so much hard as learning where the machine you are welding with likes to run the specific rod. If you have much experience it should not take too much trying to find out where the machine likes to run. If you practice on one machine and go to another, you will have to see where the new machine runs better. I have seen few machines weld the same at the same settings There is a little difference. And if you are testing, this test is about 3/4 mental. The 7016 has great open root charastics. It was developed for open root welds. I have tested a lot of welders using the 7016 root 7018 cap test. I have seen guys who can make the bead look like a wedding band and others look like hammered do-do. If you have experience running 7018 you should pick up on this after 4-5 nipples. If you have little or no experience with 7018 you are SOL. This is not a beginner weld!
BABRT's

By Kix

Date 11-02-2007 14:26

He could qualify a procedure using A/C if he does not have a WPQR already on hand for D/C. The root goes in so much easier on A/C especially with these new Inverter machines, but the old ones limited to 50 or 60 hertz do just fine as well. About the machines running different I totally agree, but the brand of rod is also a key factor in performance. Some rods won't run that open root for sit. They finger nail the whole way up the seam not naming any names or anything (Hobart 7018-1) cough cough.;-) I play no favoritism to any particular brand, but I'll tell you that Lincoln's Excaliber 3/32 7018-1 on A/C 60 hertz will put a root in like no other and I've done this with rods from all over the world.