Page 1 of 2 12 LastLast
Results 1 to 25 of 33

Thread: Need help Welding Pinhole on High pressure steam line.

  1. #1
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Need help Welding Pinhole on High pressure steam line.

    May be the wrong place to be asking this. but top welding forum on Google

    I work on steam lines with an average 140 PSI. On a 8 inch, 80 grade, 300PSI Max, carbon steel pipe. I installed a welded-in gate valve. I also installed a bypass, which where 2 holes

    on the pipe on each side of the valve and welded a weldolet on the holes. My welds for the gate valve to the pipe were x ray tested and passed as solid. my weldolet welds were not

    tested, i told the inspector not to worry about them. (BAD MOVE). both my welds on the valve and weldolets were a single pass with 1/8 6010 5P rod. the hot pass and cap for both were

    3/32 7018. few weeks later they fully charge the line, about 3-5 days later my weldolet begins to leak. it sounds like a leaf blower walking up to it from 100 ft yet a 3/32 rod wont fit in

    the pinhole. Anyways today i begin to weld over the pinhole to try and stop the leak. after chasing the pinhole for about an hour i manage to get it down to a quiet hiss. by now i have

    this 2 inch ball of metal under my weldolet, which i plan to fix when that line gets shut down in February. For now i need to take care of the leak which will most likely get bigger. i came

    here to ask if anyone had any suggestions. after some thinking today i may hammer in some wood, maybe it'll hold the pressure back enough to run a bead over it? Obviously an outage

    is not possible until February.

  2. #2
    Join Date
    Oct 2011
    Location
    Jacksonville Florida
    Posts
    2,451
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    I can't help because I haven't done anything like that, curious about the answer to the problem though. Maybe start the bead 1/4-3/8" away from the pin hole and wash the 6010 into it to seal then run a 7018 over that? Did you grind around the hole any?
    Airco Ac/Dc 300 Heliwelder
    MillerMatic 200 (stolen)
    Miller Maxstar 150STL
    Miller AEAD200LE (welding and generating power)
    Hobart MIG

  3. #3
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    i wired wheeled the hole, got it nice and clean. yes i did exactly that, started about an 8th of an inch away welding above it going downhill , tried going uphill, left to right, right to left. i was there for an hour. i actually got it to stop for about 5 seconds then i could hear it cracking then it begins to hiss. i turned the heat down to dig less metal but that damn hiss always comes back. when welding over the pin hole, in the puddle is a needle size hole the moves around with the puddle. i plan to either jam wood in the hole, or try to stop the leak completely again for that short time and spray a jet stream of ice water on it to harden it and keep running a bead, cooling it, another bead, cool it. until i can run 7018 over it. i'm motivated to fix it because i was able to bring it down from the sound of a leaf blower to a quiet hiss.

  4. #4
    Join Date
    Oct 2011
    Location
    Jacksonville Florida
    Posts
    2,451
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Could you hammer a nail into it then weld over it? I don't think wood would hold but I don't know. Or maybe heat it with a torch then hammer a nail into it, when it cools it may be sealed good enough.
    Airco Ac/Dc 300 Heliwelder
    MillerMatic 200 (stolen)
    Miller Maxstar 150STL
    Miller AEAD200LE (welding and generating power)
    Hobart MIG

  5. #5
    Join Date
    Dec 2009
    Posts
    31
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    check your PM

  6. #6
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    You may have something there with heating a nail and hit it in, thanks. but yea i didn't use a nail instead i used a rod, i actually sharpened it into a point on and when i hit in it actually worked a little, then i welded it and the rod i guess melted. i'll try a nail next time.

  7. #7
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    is there a soft metal i can sharpen into a nail? maybe brass? i'm thinking the pinhole may not be a perfect circle. if i hit the nail in, it either may make the hole bigger because nails are strong or not completely cover the hole and it leaks by, leaks less but still leaks. i say a soft metal i can hammer in, that will take form of the hole and hold off pressure, which is the idea behind jamming wood, it'll take shape of the hole. and i assume the steams condensate would seep into the wood and expand the wood

  8. #8
    Join Date
    Dec 2011
    Location
    Tampa FL
    Posts
    1,272
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Center punch around the hole to push the metal into the hole and close it up. Then you may be able to weld over it, since it wont be an active leak.

  9. #9
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    well then i was being very hard headed because my co worker kept trying to do that, he tried about 4 times after each weld but he only made the hole worse. at one point it worked and quickly welded over it but the hiss came back. kept telling him to stop, shouldve been more patient and kept trying that.

  10. #10
    Join Date
    Dec 2011
    Location
    Tampa FL
    Posts
    1,272
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    It doesn't always work, some times you can get it this way. I have never done it on a steam line, but pipes with various liquids in them.

  11. #11
    Join Date
    Dec 2011
    Location
    Tampa FL
    Posts
    1,272
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    If you get it to stop leaking then try putting just a couple of quick tacks over it. After a couple of tacks then you should be able to put a weld over it, you have to keep it a rather cold bead or it will just blow out again.

  12. #12
    Join Date
    Sep 2013
    Posts
    80
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    damn, this is scary.

  13. #13
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    "It doesn't always work, some times you can get it this way. I have never done it on a steam line, but pipes with various liquids in them."


    yea my guess is that while welding it diggs in too deep and the metal holding the pressure gets soft. maybe lower the heat and arc at that point
    Last edited by leo10a; 11-12-2013 at 07:13 PM.

  14. #14
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    "If you get it to stop leaking then try putting just a couple of quick tacks over it. After a couple of tacks then you should be able to put a weld over it, you have to keep it a rather cold bead or it will just blow out again."

    yea that's the plan i was gonna try to spray it with ice water as well to help harden it faster.
    Last edited by leo10a; 11-12-2013 at 07:14 PM.

  15. #15
    Join Date
    Jul 2013
    Posts
    91
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Ok this is a joke?

    I am a Steam a Fitter welder. If there is that much pressure the only way to repair your weld and make "safe" is to shut off the steam. Trying to weld over it, or tack it will not tie into the base metal enough to be a permeant fix.

    The leak is in the first pass and made its way through all the other weld.


    Turn off the steam, grind it out, and repair. That's the right way.
    Local 83

  16. #16
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Quote Originally Posted by RodBender View Post
    Ok this is a joke?

    I am a Steam a Fitter welder. If there is that much pressure the only way to repair your weld and make "safe" is to shut off the steam. Trying to weld over it, or tack it will not tie into the base metal enough to be a permeant fix.

    The leak is in the first pass and made its way through all the other weld.


    Turn off the steam, grind it out, and repair. That's the right way.
    Definitely the right way, i understand that. this steam lines goes into an old government building. an outage is not possible, until February.
    i'm going to stop this leak even if i have to weld a nipple on the pin hole and put a cap on it. the location of this valve is 50 ft below ground in a 50 year old manhole which is 130F.
    no standards being followed here and lack of quality. its too late. now i just need to get the job done stop the leak until Feb

  17. #17
    Join Date
    Nov 2013
    Location
    Farson, Wyoming
    Posts
    54
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Rodbender hit it on the head. Do it right, and save alot of headache. You have to repair the root first, or keep chasing the hole. We ALL have to swallow our pride sometimes, (it doesn't taste very good either) but it's better than spending a whole lot of time on a single pinhole problem that can be repaired in an hour. jmho. Rick

  18. #18
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Quote Originally Posted by Rickswelding View Post
    Rodbender hit it on the head. Do it right, and save alot of headache. You have to repair the root first, or keep chasing the hole. We ALL have to swallow our pride sometimes, (it doesn't taste very good either) but it's better than spending a whole lot of time on a single pinhole problem that can be repaired in an hour. jmho. Rick
    i may have to do that, i'll give it another try then leave it alone

  19. #19
    Join Date
    Nov 2012
    Posts
    3,039
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Weld a thread-olet around the leak, then screw a valve or plug into the o-let.

  20. #20
    Join Date
    Apr 2013
    Location
    NE
    Posts
    441
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    What caused the leak in the first place? What temperature was the base metal when you welded it?

  21. #21
    Join Date
    Jul 2012
    Posts
    386
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Quote Originally Posted by RodBender View Post
    Ok this is a joke?

    I am a Steam a Fitter welder. If there is that much pressure the only way to repair your weld and make "safe" is to shut off the steam. Trying to weld over it, or tack it will not tie into the base metal enough to be a permeant fix.

    The leak is in the first pass and made its way through all the other weld.


    Turn off the steam, grind it out, and repair. That's the right way.
    It almost seems like a troll. Isn't this an ASME pressure pipe connection? Wouldn't Hartford, Factory Mutual or another insurance company be on the hook, thence be involved. A lot here I'm having trouble swallowing, especially with the talk of it (?) being a government building.

  22. #22
    Join Date
    Jun 2007
    Location
    BC Canada
    Posts
    925
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    I almost always carry horse shoe nails in my pockets. They are very useful for fitting and stuff. You can go ahead and try pounding one into the hole and welding around the head, but not my recommendation. What if it blows back out? What if it breaks off inside? Where is that steam going lol? I once heard a story about a guy taking a broom handle and waving it in front of a pinhole in a steam line. It cut the broom handle in half. I also just recalled a friend of my dads getting really badly burnt by steam at work. I was going to suggest throwing quick tacks over the hole then an over lay of beads, but I think Ill pass. Be safe!
    Nothing Ever Got Done By Quitting, Never Give Up.

  23. #23
    Join Date
    May 2013
    Location
    Chicago
    Posts
    118
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Ime no expert but that just sounds like a bad idea.
    PROUD AMERICAN

  24. #24
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Quote Originally Posted by TimmyTIG View Post
    Weld a thread-olet around the leak, then screw a valve or plug into the o-let.
    Yes i may do that, but after reading a few suggestions i may have to leave it alone. Suck it up and wait till a shutdown in Feb.

  25. #25
    Join Date
    Nov 2013
    Posts
    16
    Post Thanks / Like

    Re: Need help Welding Pinhole on High pressure steam line.

    Quote Originally Posted by TSCGG13 View Post
    What caused the leak in the first place? What temperature was the base metal when you welded it?
    I believe when running the root weld on the weldolet i didn't penetrate the base metal enough. At eye sight it looked fine but the x ray test wouldve showed cracks or slag

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Page generated in 1,664,638,780.58933 seconds with 11 queries