magnetism

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I've been welding drill stem pipe on cattle corrals and I'm finding some of the pipe has a lot of magnetism in them and getting blow back. I have quit using 6010 , 6011 and switched to 7018 and doing some preheating with better results. Do any of you have any other ideas I might try?
Reply:You could try wrapping your ground lead 4 or 5 times around the pipe. If that doesn't work wrap the lead the other direction. Switching to AC helps too. Last resort, heat the weld zone cherry red, and let it cool.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:I didn't heat the weld area cherry but did heat it and it darn sure helped a little
Reply:That's why you gotta beware when that pipe is cheap.Arcon Workhorse 300MSPowcon 400SMTPowcon SM400 x 2Powcon SM3001968 SA200 Redface1978 SA250 DieselMiller Super 32P FeederPre 1927 American 14" High Duty LatheK&T Milwaukee 2H Horizontal MillBryan
Reply:Gas less flux core wire that runs on DCEN is a big help also. How would you like to splice another section of H-beam on these after they had the crap beat out of them? That's when you'll get a lesson on magnetism! Attached ImagesDon’t pay any attention to meI’m just a hobbyist!CarlDynasty 300V350-Pro w/pulseSG Spool gun1937 IdealArc-300PowerArc 200ST3 SA-200sVantage 400
Reply:Thanks for the info. I'll bet that is quite a problem after a thumping like that. And blawless I didn't buy the pipe just welded it
Reply:help me understand the problem on the h-beam. how does it cause you a problem. Does the pounding induce a magnetic field in the beam? Thanks for the lesson
Reply:Magnetism can be imparted to ferrous metals (and it varies by alloy composition) by repeated hammering or stroking in the same direction.I have observed that forks on a typical forklift become magnetic after they have been in service for a year or more due to the constant, "one direction" scuffing/stroking they get during normal operation.I learned that when I used a forklift to scoop up a welded steel project we had been working on in the shop.  The floor was littered with slag, electrode stubs, and grinding waste when I scooped up the finished product with a forklift.The magnetized forks picked up a lot of other stuff along with the product.  A few whacks on the topside of each fork with a 2 pound hammer shocked most of the stuff loose, but I lowered the forks back down into the debris and they picked up a load again.Regarding how magnetism can cause a problem:  The arc welding process produces its own electromagnetism and usually this has a  negligible (helpful actually) effect on the actual welding puddle and transfer of deposit material.  Sometimes the electromagnetism becomes amplified or exaggerated in the wrong way and a condition known as "arc blow" develops, and really interferes with the arc and puddle control.Residual magnetism in the metal you want to weld can aggravate or spoil the electromagnetism of the arc welding process, inducing arc blow or arc distortion.If you want to see how magnetism affects a welding process, just stick a big magnet on a piece of steel and try to weld a bead near the magnet.  You may not notice anything at one point adjacent to the magnet but move to a different place and you may not be able to weld at all.Magnetism is pretty pervasive in modern technology, just about everything electronic exploits it in some way.  Years ago at my job, one of our "class clowns" taped a large chunk of permanent magnet to the backside of a supervisor's CRT computer monitor when the supervisor was away from his desk.  The magnetism twisted and distorted the monitor display so much that the supervisor could not use it and had to log onto a different computer in another office to continue working.  A couple days later they said management was real pizzed when the IT guy they called handed them the chunk of magnet and tape about 10 seconds after arriving for the service call.
Reply:Originally Posted by gator9329Does the pounding induce a magnetic field in the beam?
Reply:I knew someone on here would be able to put it into words a lot better than myself. I have ran into magnetism a lot on I and H beams through the years but this drill stem was really something else until I discovered the heat trick. Like I said before it didn't take it all out but It did help a lot.
Reply:I've never done it my self, not sure it would work on pipe anyway. Guys have told me they have got away from magnetism by smacking the metal with a double jack.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:6011 on AC is what I use at work. The steel cased batteries are pretty much unweldable with anything else.I surprised you didn't have any luck with them. Did you use AC?Last edited by kald; 01-11-2014 at 08:31 PM.Idealarc 250AC 225SVictor OA-older made in USA stuff.And a crap ton of other stuff.
Reply:Putting as many tacks as you can on the joint will not only preheat it, it will draw from both pieces some of the magnatizum and allow you to finish the weld.Swanny
Reply:Sometimes tacks didn't work for me because the blow back was like using an air arc on it.
Reply:Originally Posted by Tjzarothe blow back was like using an air arc on it.
Reply:When welding magnetic pipe and having a problem starting the arc, just move around the pipe 90 degrees and try again. The magnetism isn't the same polarity all the way around so some where around it you should be able to start. The more weld you get on it, the less it affects your weld.
Reply:The problem with moving the pipe is that one piece is cemented in the ground and the top rail is already tacked or welded to other post.
Reply:Originally Posted by CEPI've never done it my self, not sure it would work on pipe anyway. Guys have told me they have got away from magnetism by smacking the metal with a double jack.
Reply:I will be trying the hammer on the pipe for sure.
Reply:I find that stepping down a rod size and reducing current helps me combat arc blow. This helps greatly when welding H shaped structural beams down to pile caps. I am welding lots of these at work right now. Arc blow is terrible in the corners when welding these.JasonLincoln Idealarc 250 stick/tigThermal Dynamics Cutmaster 52Miller Bobcat 250Torchmate CNC tableThermal Arc Hefty 2Ironworkers Local 720