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Impact wrench and sockets

Good morning to all. Has anyone had success using impact wrench to remove large plugs from boilers? Talking about 2.5" and 3". Which wrench are you using? What size sockets? Thanks.


  • pecmsgpecmsg Posts: 854Member
    PB Blaster
    Bigger wrench
    Bigger Cheater

    When reinstalling..........Never Seize!
    Been using wrenches successfully. Can be a pain. Especially with limited access.
  • STEVEusaPASTEVEusaPA Posts: 3,189Member
    I don't think you listed 'Cursing' & 'Swearing' enough. Add in re-evaluating life choices.
  • nibsnibs Posts: 346Member
    I try to keep a strong young person on call.

    On a more serious note, read an article years ago that tested various penetrating oils, the best was a 50/50 blend of acetone and ATF.
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,968Member
    Plugs in a boiler are a PITA and because the plugs are cast iron and recessed in the jacket UGH.

    Drill bits and chisels work as well as all the above you try everything can be very time consuming.

    I always "Plug" boiler with a nipple and a cap. First the nipple sticks out so you can get a wrench on it, second you have two threads instead of 1 (one of them is likely to be wrenched off) and thirdly @pecmsg recommended Never Seize.

    Why people don't use Never Seize more often baffles me. I use it as pipe dope with Teflon tape and you can always get it apart even HP steam that's cooked it for years.

    Put it on LWCO gaskets and you can take the controls apart with no issue, the gasket will fall out and you can even use the gasket over in a pinch
  • Mike_SheppardMike_Sheppard Posts: 581Member
    Amen to anti seize on gaskets. I love it when I take a LWCO apart and the gasket just falls off. We used to have a guy who put them on with hi temp silicone...

    I had a 3 inch plug in a KN Boiler section I had to get off. It had a recessed square in the middle. I got a 3 inch plug with a raised square head. The raised square fit in the recessed square and I used a pipe wrench to turn it.
    Never stop learning.
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,968Member

    Good trick with the 3" countersunk plug. I have used square drive socket extensions on the smaller sizes.

    I usually scrounge around and find something to jamb in their to get a wrench on but your plug idea is the best.

    just skipping countersunk plugs is the best idea!!!
  • JBFBMechJBFBMech Posts: 20Member
    Drill,sawzall,hamer, and chisel.
    Good morning. I have used some of the methods mentioned above. I have never used an impact wrench to remove a plug. Please let me know if you have had success using an impact wrench to remove 2.5" and 3" boiler plugs. If yes, what size sockets did you use? Thanks.
  • SailahSailah Posts: 794Member
    edited January 15
    No direct experience with boiler plugs but I have an 18V Makita impact with 1/2" anvil. Thing is an absolute beast.

    My biggest pneumatic impact is an Ingersoll Rand with 750 ft-lbs of torque. The Makita is 1200 ft-lbs.

    I didn't believe it so I ran the nut on my trailer hitch with the air gun and let it hammer out for 10 seconds. Makita ripped it off like nothing. So then I hammered it back on with Makita and the Ingersoll wouldn't move it. Not very scientific I know.

    But if you already have an 18V lithium tool setup, adding the big impact gun is a great tool to add. I have a Sunex impact sockets up to 1 1/2"

    My parents have B&J steam traps. 3 years ago I wanted to swap out their cage units so I brought home a 24" Crescent and 24" pipe wrench. Leaning on both wrenches my dad and I couldn't get the covers off. I was worried I was going to snap the pipe. This Thanksgiving I went home and brought the Makita. With a crescent as a backup, just blipped the Makita and cover came right off, no wrist torque either.

    Try one, you'll be amazed at the power.
    Peter Owens
  • jumperjumper Posts: 1,355Member
    Saw a guy using a manual impact wrench. It was a thingy that sockets fit on. The guy would rap a tap tap the thingy with rubber mallet and eventually stud would move. Said that the secret is to rap a tap tap; not to whack away. Also said to twist thingy opposite to way you want stud to go. So he'd twist clockwise to unscrew?

    Also there's a time factor. Kroil and come back later.
  • LeonardLeonard Posts: 840Member
    edited January 15
    HEAT......On heavily rusted car exhaust manifold studs...yellow hot manifold flange and wet rag to cool studs, for max temp difference. Oxy-acetylene

    But suspect might not be able to heat a boiler casting that hot ....warping, leaks , ect. Never tried a boiler..... yet
  • 1Matthias1Matthias Posts: 136Member
    My usual method involves a drill bit and a sawzall, with a hand hacksaw near the end to prevent damaging the threads on the item to be saved. Seems to work ok.
  • JUGHNEJUGHNE Posts: 5,865Member
    I think the biggest challenge would be finding the right socket to fit a 3" square head plug.
    I have a 18 volt Milwaukee probably similar to Sailah's (of course mine is better because it is red ;) ).
    The trap cap removal jobs made the investment in this pay off many times over.

    I have square head sockets ….8 point up to maybe 1 1/4"
    Having twisted off the corner of a square head plug, these were a must have. Just use one once a year and life is good.

    I wonder if a pneumatic impact chisel applied to the outer flat edge of the plugs would help loosen them. Trying around the circumference at several points might loosen.

    I was also wondering about some impact "shot" device that would crack smaller cast iron fittings. Perhaps the old Hilit 22 blank powered nail driver....without the nail...if the concussion/impact would crack the fitting.
    Or IIRC, packing plant kill floors have some form of stun gun that delivers a concussion shock to the beef without an actual bullet...………...these are just crazy ideas.....DO NOT try this at home!
  • jumperjumper Posts: 1,355Member
    >> biggest challenge would be finding the right socket to fit a 3" square head plug<<

    What's the biggest screw extractor drill bit?

    Nobody likes having to come back days later but penetrating oil works wonders given enough time.

    Cast iron is supposed to not fuse? Neither are dissimilar metals?
    So it really boils down to rust busting. Rat a tat tat.

    Interesting description of loosening big nuts in novel, The Sand Pebbles. Came down to big enough wrench with heavy enough sledge. Definitely don't try that.
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,968Member
    Shocking with a hammer make a big difference. Of course you don't want to break what you want to save....common sense.

    Having a helper put some beef on a wrench while you tap with a hammer works pretty good sometimes.

    Plugs and bushings that are Cast Iron are difficult for anyone.

    My favorite tool is an angle grinder with a cut off good on plugs I know. I have also used a small DREMEL tool with a their cutoff wheels for small stuff. Cuts slow but when your out of other options it works
    Update. Weil Mclain boiler. Eight years old. 1.5" skim tapping plug. Used Milwaukee 18v 2767-20 impact wrench. 34mm 12 point socket. Came out in seconds
    edited July 5
    Update. 50 year old steam boiler. 2 2" plugs on top of boiler. Used impact wrench. 40mm 12 point socket on one. 41mm 12 point socket on the other. Came out in under 20 seconds each. Started off wrench in clockwise direction for a second. Switched to counter clockwise. Easy as pie. Easier then blowing my nose. I AM SOLD!!
  • Danny ScullyDanny Scully Posts: 1,209Member
    Hmm...why were you taking plugs out of a 50 year old boiler?
  • JUGHNEJUGHNE Posts: 5,865Member
    Because now he can!! ;)

    The only plug I have failed to get out is in the bottom of a CI cond pump. 18V 1/2 drive would not get it. Not really necessary but thought I would try.
  • SeanBeansSeanBeans Posts: 356Member
    The things that get us going! LOL
  • EBEBRATT-EdEBEBRATT-Ed Posts: 5,968Member
    Just goes to show that vibration will take anything apart....intentional or not
    > @Danny Scully said:
    > Hmm...why were you taking plugs out of a 50 year old boiler?

    As stated. Because I can. Boiler is going into garbage heap. Just wanted to see if it would work.
    The key is having impact sockets that fit. When I first bought the impact wrench, I bought every 12 point socket, up to 50 MM. On the above mentioned boiler, the 41 MM fit one if the plugs but was slightly oversized for the other plug. Both the 40 and the 41 fit the plug. The idea is to use the smallest socket that fits. Multiple sizes will usually fit. I can't say if I have made my money back yet but I ain't never going back to another method. No way no how.
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