Arc Welding Galvanized Pipe???

Discussion in 'Shop Talk' started by Ken Scharabok, Aug 5, 2004.

  1. Ken Scharabok

    Ken Scharabok In Remembrance

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    One of the blacksmithing tools I make is a step mandrel. Basically short sections of pipe joined in a stairstep fashion with the arc welding inside using stainless rod. I am using black pipe, but two sections are thick wall and I have to pay someone to lathe them out inside to fit the section going into it. I can find galvanized water pipe of the correct OD & ID; however, I have not had much luck welding this pipe even after cooking off the zinc in my forge and then filing off the scale inside the pipe. Weld just doesn't want to stick to it. Any suggestions for taking off the galvanization without damaging the pipe?

    Ken Scharabok
     
  2. moopups

    moopups In Remembrance

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    I use a cutting torch to blow off the galvanized layer, then grind the surface if you have something that small to enter the inside of the pipe, die grinder and stone here. I have had luck with 6022 rods also, they are a drag rod used in the ornamental iron industry, normally only available in 50 pound boxes at about $70.00. This rod can weld roof tin to railroad iron.

    All readers please remember that the fumes from galvanized metal in a closed space can be deadly.

    Ken, I think your method of heating is too slow and your bakeing it in, just a personnal opinion, no fact to place base on info.
     

  3. agmantoo

    agmantoo agmantoo Supporter

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    I make gates for the farm with galvanized pipe using a fan for ventilation and 6011 welding rod. Does not seem to be a problem!
     
  4. Ross

    Ross Moderator Staff Member Supporter

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    6011's here too or the MIG but we grind the galvanizing off first and spray on the welded area with paint or the galvanizing repair stuff. A chemical respirator makes the job all the more enjoyable. I gotta get an air supply mask and a suitable compressor!
     
  5. Ken Scharabok

    Ken Scharabok In Remembrance

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    My propane forge will go from zero to about 2000 degrees in about two minutes. In fact it gets so hot I melted cast iron in it when I left it in too long. I am aware of the zinc fumes. I start the forge, turn on the exhaust fan and leave the building for a bit. Any welding fumes can be harmful over time. Can cause what is called "Parkersonism". Parkenson-like symptoms, but not Parkenson itself. Big class action lawsuit brewing over it now. Normally when I weld I try to stand upwind of the welding.

    Ken Scharabok
     
  6. Ken Scharabok

    Ken Scharabok In Remembrance

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    OK, guys, don't laugh but I have not used DC rod, such as I think 6011 is, before. All I do is reverse the leads on the welder - right? Temperature and technique stay the same?

    Ken Scharabok
     
  7. deviator12000

    deviator12000 Member

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    All my welding buddies have always suggested drinking milk before doing any galvanized welding. Never bothered to ask why, so I'm still stumped on that one. However, I do know that the fumes can kill.
     
  8. agmantoo

    agmantoo agmantoo Supporter

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    Ken, the 6011 will run either AC or reverse polarity DC. Most AC/DC welders have a polarity reversing switch or plug ins. Reversing the connections of the ground and the electrode holder cables would reverse the current. You need to get some 6011 and experiment. I seldom weld thin materials and I have grown used to using the 5/32 rod. The 6011 is very forgiving. I intend to try some 7018 AC the next time I buy rod as I have often been told to use the 7018 but when I tried it I was not satisfied as I could not restart the rod easily. Hopefully the AC will run better on my welder and with me.
     
  9. rambler

    rambler Well-Known Member Supporter

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    I thought the fumes made you sick to your stomach, not really dead.....

    Anyhow, calcium is the antidote, so a glass of milk keeps you from feeling sick.

    --->Paul
     
  10. deviator12000

    deviator12000 Member

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    rambler: I'd say that sounds right. The older I get the more I forget. Still, it'd be a good idea to keep plenty of fresh air around. For a quick job, I just hold my breath, weld, then get the heck out of the smoky area.
    I think the "guys" said something about buttermilk. How technical do we get on this subject? I guess as technical as it takes to be safe. Buttermilk is supposed to coat the stomach lining. Does that mean regular milk won't help worth squat, except for a feeling that your'e okay, and that it's helping you?
     
  11. Ken,
    I was showing my husband the forum and he is a welder so got all excited when he saw this thread. He says use a three thirty second 7018 and that will give you more control. He says remove the galvanization by using a 4" grinder. It won't get it all off, but enough that you can do the job. And I have no idea what any of this means, but I hope it helps. He says if this doesn't work, you need to hire the job out.

    Brooke


    [
     
  12. Skaggydog

    Skaggydog Guest

    The pipe is made without galvanize, buy it that way.

    Without ever even hearing of 6022, I know by its last two digits that it is not a good rod to weld over galvanize. You want a fast freeze rod like 6010. MIG can also do a good job. 6011 is an AC rod made to take the place of 6010 with an AC machine. Galvanizing will come off with a grinder. Grind until the sparks change, indicating that you are grinding steel. It will weld all right for what you are doing without removing all, even without removing any of the galvanize, but the more you remove, the easier and better the welding. Got milk?
     
  13. devriesj

    devriesj New Member

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    You can't stick-weld to galvanized pipe without taking the galvanizing off first. You might mess around and actually get a bead going, but you won't get any penetration. The 4" grinder is the way to go...get the galvanize off first. And they're right...very toxic fumes from welding galvanized pipe. Any 60- or 70- rod will work once you get the coating off.
    devriesj
     
  14. srj

    srj Member

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    hi all
    sorry for butting in but i see a couple of myth's carrying on .
    1st milk don't work ,,it's not your stomich your worried about ,it's your LUNG'S ,a direct path to the blood stream ,remove / get clean mat. use a fan or better yet get a respirator both already suggested , if your doing galv. in a closed shop area stay away from the flume ,unless you like your worst flu & worst hangover rolled into one for 6-12 hr's "FLUME FEVER" it a'int fun

    2nd 6011 will burn thru galv. and give good penatration, it a'int pretty but 6011 never is,,so will 6013 depends on how much integrity is needed, 7018/24/28 + others ,,just run a lil hotter than normal .but all in all removel is best

    mig. without removal duel-shield is the best i've seen alot less splatter ,cleaner weld & better dig than hard wire co2 good 90/10 best

    Ken / Agman run the 7018 dc reverce , they make a 18 rod ez strike ,not near as sticky as before ,6011 is fairly universal ,18's prefer dc
     
  15. Ken Scharabok

    Ken Scharabok In Remembrance

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    I should have noted welding is on the inside of the pipe. I have to reach 1" into the pipe to try to weld the shelf to the side. I can burn off zinc in my propane forge, but cannot get at the inside of pipe to really clean it well there. After I do the burn-off, can I soak the pipe sections in mild muriatic acid or vinegar?

    Ken Scharabok
     
  16. Bob_W_in_NM

    Bob_W_in_NM Well-Known Member

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    I've used the muriatic acid trick a number of times in my life for removing zinc
    galvanizing. I use a solution of about 50% acid - 50% water (not critical).

    Works really great if you can just soak part in solution in plastic pail. (I wouldn't use a galvanized bucket! - hehe) You'll know when it's done because chemical
    reaction stops. (Be careful - best done outdoors.) You can also stick the end of a longer piece of pipe in the bucket and rest upper part against something
    (wall, etc.) and just remove galvanizing on end to be welded.

    When you're all done and the weld is finished, you can use aerosol cold galvanizing compound on the welded (and ungalvanized) area if you want to.

    I've also used the muriatic acid trick to preapare galvanized parts for painting.
    If it's a large surface, you'll have to use a rag, rubber gloves, etc. Outdoors with a nice breeze blowing the fumes away from yourself is great.
     
  17. Msrinivasarao

    Msrinivasarao New Member

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    Hi,
    I am working with consultancy we are doing piping projuct we are using Galvanized pipe size 25mm to 350mm we need sutabul welding roods and welding proce

    Thanku
     
  18. Windy in Kansas

    Windy in Kansas In Remembrance

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    Hello and welcome to the forums. I'm sorry that I can't answer your question but did want to extend a welcome.
     
  19. Ozarka

    Ozarka Well-Known Member

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    Ken
    Since you make these to sell I am assuming that you make them in batches...go buy Sch. 40 black pipe and forget about the zinc poisoning issues and side effects. Live longer so you get to see your g'chilrens grow up.

    Remember the blacksmith Jim "Paw Paw" Wilson. He survived Green Beret duty in 'Nam only to be killed in 2004-5 by pneumonia that developed from zinc fumes he breathed in his own smithy. When you're dead the cost of new pipe don't seem so expensive. Another good man gone and all because he didn't heed the warnings.
     
  20. ozarkgem

    ozarkgem Member

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    I think its the lead in the galv that is harmful. plus some other stuff I'm sure. not worth the risk to me.