help, magnetic field during welding.

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hey everyone. i haven't been on the forum for sometime, but I've come to a point were I'm stumped.ok I'm working at Michelin in Anderson SC at G83. I've been there four months when some of the buildings were just dirt. lol. Anyway all I've been welding there has been 1" to 12" sch 40 carbon pipe mostly in the rack. the problem I've encountered has been a magnetic field when i tig weld. I've asked many question why and how but i still have no really answer to to help me.  so may let me explain everything I've encountered at Michelin since I've worked there.i worked at Red Oaks Projects at Michelin first and when i worked there everyone clamped their grounds on the beams. let me say this i would get shock every time when i even try to change my tungsten or if i was touched by my tungsten. i was zap like 8 times one day that i almost quit that day and it was a small tingled but like getting zap with a 110v. now at G83 at Michelin you're not allowed to clamp to the beams but on the direct line you're working on. awesome!!! but i now I've uncounted magnetic field when welding. now I've been told and tried many things so here are some of the things i've tried.clamp to the end of the pipe you're working on.clamp 5-10ft from the spot you're working at and grind a spot where you're working at.make a copper wire lasso and wrap around the pipe depending where you clamp on the wire that hangs off the pipe, it will give you resistance .wrap you ground wire 4-5 time like a candy cane counter or clockwise on the pipe.and finally a compound of many variation of above.please if there's something i'm doing wrong help.here's what I'm using:Lincoln Vantage engine welder and they ground it.I weld with a 26V tig rig, lg gas lens, 8 cup, a 1/8" tungsten @ 130-150 amps1/8" wire and 1/8" gap thank you any help will be helpful.it's trust and character I need around me. You know, who you choose to be around you lets you know who you are. One car in exchange for knowing what a man's made of? That's a price I can live with. - Hans
Reply:Why do you think you are having a magnetism issue? What symptoms are you seeing. When you wrapped your lead, did you see any difference? Did you try wrapping it the opposite way?
Reply:You have to try and find a spot in the fit where the magnetism is least bad and start welding there. The more root you get in the less magnetism you'll have.I never had any luck with wrapping the ground lead. Another thing you can try is tack a few pieces of small bar in between the bevels, like a bridge. Anything that gets the two pieces connected will lessen the magnetism.
Reply:You can also heat the area to a dull red, let it cool, and the magnetism will go away.Don’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Originally Posted by CEPYou can also heat the area to a dull red, let it cool, and the magnetism will go away.
Reply:Originally Posted by walkerOOhhh, didn't know that. I am adding this tool to my toolbox. Thanks!
Reply:Originally Posted by mad welder 4Yes its called heating to the Curie point.
Reply:Using AC if suitable for the rod and position will counter arc blow from magnetism."The reason we are here is that we are not all there"SA 200Idealarc TM 300 300MM 200MM 25130a SpoolgunPrecision Tig 375Invertec V350 ProSC-32 CS 12 Wire FeederOxweld/Purox O/AArcAirHypertherm Powermax 85LN25
Reply:Probably not related to your problem but why such a large tungsten? For 130 - 150A I would use 1/16" tungsten, maybe 3/32 at the top of that range. A sharp tungsten of the right size has a more focused arc which may help keep the arc where it is wanted.JohnA few weldersA lot of hammersA whole lot of C-clamps
Reply:^^^If you're working for somebody else, you use what they give you.
Reply:thanks everyone for their input. i would like to add when i strike an arc, my arc is straight and stable. what i'm having a problem with is my filler wire, it tend to want to stick to the bevel wall before i melt it. like steel sticks to a magnet and then when i melt the rod, the molten metal want to pull up towards the tungsten. not like i dipped my tungsten but if its being sucked up. its hard to explain.it's trust and character I need around me. You know, who you choose to be around you lets you know who you are. One car in exchange for knowing what a man's made of? That's a price I can live with. - Hans
Reply:I sometimes work in a plant where there are humongous magnetic fields from production equipment.   The production has to be shut down before welding can occur in that area.  Otherwise, once the steel melts, it just "heads south."  I understand that it takes a few hours for the residual magnetism to reside before welding can happen.  I'm heading down to one of these facilities tomorrow.  If I get a chance, I'll ask one of the weldors for some ideas.Tim
Reply:If there are large induction heaters or lage motors or sub-station sized transformers, there will be huge magnetic fields in the vicinity.You may want to look up "Faraday Cage" for ideas on isolating your welding space from such interfierence.Be wary of The Numbers: Figures don't lie,. but liars can figure.Welders:2008 Lincoln 140 GMAW&FCAW2012 HF 165 'toy' GTAW&SMAW1970's Cobbled together O/A
Reply:http://weldingweb.com/vbb/showthread.php...low&highlight=This may not be related at all but will they let you try a different welding machine. I weld stainless tube cladding on magnet tubes for a client.  My Miller XMT 304 has terrible arc wander. My old AO Smith transformer machine had no problem.  Lucky I still have access to my old machine. Dan D.Last edited by DanD78; 10-08-2013 at 10:00 PM.