A new discovery on welding magnetized steel

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This is for the guys with pipe mode Lincolns. I had to make a repair on a roll off container yesterday and much to my surprise it was magnetized as bad as any drill pipe I have ever seen. Needless to say the feeder with NR211-MP DID NOT WORK (that's how I found out it was magnetized, lol). Well I can also tell you it didn't work well at all in stick mode either. I switched over to pipe mode and instantly thought about all the times I now wish I'd had that option. It works really well. Now to get to the kicker on this -- it was all overhead. And Zap just thought he got all the fun stuff.The difference between art and craft is the quality of the workmanship. I am an artist.
Reply:OK,I'll ask the dumba$$ question. What is "pipe mode"?                                                   MikeOl' Stonebreaker  "Experience is the name everyone gives to their mistakes"Hobart G-213 portableMiller 175 migMiller thunderbolt ac/dc stick Victor O/A setupMakita chop saw
Reply:Magnetized? I'm curious, any idea how it got magnetized?
Reply:Steel that is rotated or run in and out below ground picks up magnetism from the earth's magnetic field. Tubing and sucker rods in oil wells become magnitized from this mechanical action. Drill pipe that is used to drill the wells is even worse because of the amount of rotation and the trips it makes in and out of the ground. Some is extemely difficult to weld. I welded in a potash mine for a few years and the mining machines that actually cut out the ore had four big rotating cutter shafts and these machines became magnitized to some extent. The equipment that just rolled on tires or cat tracks didn't do this. I've never found any pipelines that just lay in a ditch to aquire a magnetic field. It seems that the movement in and out or around and around below the surface is what it takes to create this.
Reply:i have worked on several pipelines that had become magnetized from "just being in the ground" It makes an x-ray open root very difficult.
Reply:Maybe depth in the ground or length of time in the ground has something to do with it. Probably 95% of the ones I worked on were in waterflood systems and weren't very deep in the ground due to our rocky terrain. None of them were really old either. The oldest of the several floods I maintained was about 25 years old when I started keeping it up.Some of the production lines were older but were still pretty shallow. I never found any magnitzedlines and I replaced a bunch of cement lined pipe in the waterfloods. At one time I had six different fields to keep operating. Had a lot of trouble with trying to get rid of water but never any magnitizm.
Reply:the ones i had issues with were pre 1960 natural gas lines. also, a north south line has more chance of acquiring a field than east west
Reply:Oldtimer that's not the only place pipe goes magnetic, I've seen above ground piping that had a bunch of work before it could be welded, a huge pain in the ...Maybe it's a hemisphere thing but at times we can have a lot of trouble with it down here when you get the stick out, even the tig can have trouble and I don't use that mig stuff anymore so don't know about that I'd rather be hunting........USE ENOUGH HEAT.......Drifting around Aussie welding more pipe up, for something different.....wanting to get home.
Reply:Maybe I've just been lucky. I've never run into magnitized lines that were  buried or in the air that were orignally built from nonmagnetized steel. I have cut the upsets off magnitized tubing and welded it for flowlines and it stayed magnetized. We used a lot of tubing  for floelines after it had been downgraded to structrual. If it has been in an oil well it will be magnitized when it comes out. The more times the tubing is pulled and ran back in the hole the worse the magnitizem. Of course sucker rods spend their life going up and down so they are all highly magnitized and work hardened to boot. I am kind of glad I don't have to fight that stuff anymore.
Reply:There is a thread at the AWS site on this topic for stainless.  One thing people claim is that some stainless alloys can become magnitized from bending and forming operations.  I was forced to try to weld an actual magnet in for a jet engine sensor.  I made the designer change the process to laser since we had an impossible fight going with the TIG.
Reply:Is the steel used in pipeline and drilling operations magnetized because of the earth's magnetic field?  Or because it's sitting in or drilling through low grade iron or minerals that are strongly magnetic?  I have heard that there are places where a compass is useless because of the magnetic ore deposits near the surface.  The local magnetic fields from these ore deposits are supposedly much more powerful than the earth's magnetic field....Passing steel through an electric field can induce strong magnetic fields as well.  If it sits in a magnetic field long enough it will in turn become magnetic.  This can happen faster if the steel is heated up above the A1critical temperature(Curie temp) and allowed to cool slowly in a magnetic field.  I don't have any personal, first hand experience with oil drilling equipment, but I imagine that large motors play an important role in drilling.  The electric fields around these motors could easily induce magnetism in the drill rod as it moves through the vicinity of the motor.  If the pipe sits in the filed long enough, it will become magnetic.  Likewise, I know that they send equipment down pipelines to clean and inspect the pipe.  If any of these inspection capsules use eddy current testing, some variant of magnetic particle inspection, or even electric motors for locomotion, perhaps they could magnetize the pipeline just by passing through it over and over.This might also explain why oldtimer didn't see as many problems with water piping.  I doubt they use such tools to monitor the lines for leaks...Or perhaps the soil and rock in his area isn't composed of magnetic ores...Just food for thought...Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:A-DAB, There are no magnetic ores in this part of the world so it would be from the earth's magnetic field. I have heard of a couple of electric powered drilling rigs back in the 60's but never ran across one. All I have ever worked on or watched run are powered by diesel engines. You can tell when they start pulling pipe to make a trip and the engines blow a big cloud of black smoke when the blocks start up. None of the drilling rigs I welded on had any magnitized metal unless they had something on them built out of old drillpipe.Never heard of a waterflood running a monitor in the pipe though I don't doubt that somewhere an engineer has done it. It is usually pretty easy to tell when you have a leak in a waterflood. Most you can see spraying or if the station pressure drops you start driving lines looking for water.I repaired and moved a lot of flowlines too which contained a lot of oil in combination with produce water. Most were on top of the ground but some were buried but I never found any magntism. Tank batteries contain a lot of piping and several pressure vessels and storage tanks. We did a lot of work maintaining and upgrading them and I never encountered any magnitized material in any of those either. Same thing with gas producing wells and the facilities that go with them.I can understand how a pipiline could pick up magnitism from magnitized ore. I think it would be the same thing as laying a screwdriver on a magnet and then finding it magnitized.
Reply:Well, in this case I am pretty sure it picked up the magnetism from the rather large electro-magnet they use for emptying the container at the mill. The container is used for hauling scrap steel, iron, engine blocks and transmissions. The reason I am not positive is because I haven't encountered the problem on any of the others. I should probably add that this is the only one of the cans I have worked on that was sitting on a trailer. All of the others were sitting on the ground. That may or may not have something to do with it.I've never seen an electric drilling rig. All of them I ever worked on used big diesels with a chain or belt drive. I do recall hearing about a diesel - electric rig that was under construction when I worked for Halliburton. Not sure if it was ever completed as this was about the time the oil market went in the dumpster in the early eighties. I did make a few cutoffs and installed a couple of wellheads on all hydraulic rigs in the late nineties. They were little bitty things that only had a two man crew and came out of the hole laying down. I've never encountered any magnetized parts on a rig. I have worked with some pulled casing a couple of times and had no problems with magnetism. This was casing that had been set shallow but I think you would probably have the magnetism problems with deep casing if you had any way to get it out. I've made repairs on a lot of pipelines back home in New Mexico and never encountered any magnetism. I have also worked on quite a bit of oil and gas processing equipment (some of it 50+ years old) and never encountered it. The tubing and rods come out of the ground with it, but the pumping units themselves don't pick it up. Don't ask me why I am a welder not a geologist, LOL.As far as I know pipe mode is only available on Lincoln Rangers (I am unfamiliar with the new large engine drives and some of them may have it as well). Switching from stick mode to pipe mode results in a much hotter and very sharply focused arc. I don't know how it works but boy do I like it for running 6010/6011, and in this case it worked really well with 7018.The difference between art and craft is the quality of the workmanship. I am an artist.
Reply:So, I learn something new everyday Oldtimer and Jolly Roger.  Thanks.  I know almost nothing about oil drilling, but I know a little bit about oil refining.  The analogy about magnetizing a screwdriver with a small magnet is right on the money.I'm surprised that electric motors on drill rigs aren't more common.  I suppose I can see using a diesel motor to drive the equipment.  But electric motors driven off of a diesel generator would seem to have some real advantages to me.  Electric motors have 100% of their torque available at all speeds.  With a big enough motor, you could direct drive the drilling equipment at virtually any speed.  [thinking outloud] But then again maybe the diesel engine drive is less expensive....The magnetic ores I referred to are commonly found in the upper pennisula of Michigan, Minnesota, and throughout Canada.  I'm not aware of anybody mining iron ore in the southern states, so it doesn't surprise me that you've not heard of this before.Benson's Mobile Welding - Dayton, OH metro area - AWS Certified Welding Inspector
Reply:The lack of electric motors could have something to do with the market for new drilling rigs going in the dumpster about 1983. As far as I know there haven't been any new large rigs built in the Permian Basin since then. It was a big deal when Watson - Hopper built their first new pulling unit in around 20 years. They have huge generators on these things but still use huge Caterpillar industrial engines for the power to the rig. Most of the newer rigs will have 3 or 4 of these all hooked together providing the power. You need huge amounts of torque when what you are lifting is measured in thousands of tons. I think I actually got to see the draw works off of a steam powered rig today. Built by American Hoist and Derrick. I hope to get some decent pics tomorrow.The difference between art and craft is the quality of the workmanship. I am an artist.