Results 1 to 20 of 20

Thread: Welding crack on dump truck box frame

  1. #1
    Join Date
    Sep 2021
    Posts
    6
    Post Thanks / Like

    Welding crack on dump truck box frame

    Hello,

    I have this crack that I would like to weld. I know how to weld but lack experience to know the best way to weld this crack.

    Do I Weld all sides of it? Do I Need to fish plate it? If so where

    This pictures are not the greatest. I took them in a rush and didn’t check them.

    This crack is a few inches from where the box pivot pin is installed. The pictures went sideways when uploading don’t know how to fix this!!

    thanks in advance
    Attached Images Attached Images   
    Last edited by IslandHD; 3 Weeks Ago at 09:51 PM.

  2. #2
    Join Date
    Mar 2021
    Location
    Near Roanoke, VA
    Posts
    506
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    Never run any beads perpendicular to the length of the frame,,
    only run weld beads parallel to the length of the frame.

    Since no welds will be going the direction of the crack,, you will need fish plates.

    AND,,, Welcome to the forum!!

  3. Likes _Weldman_ liked this post
  4. #3
    Join Date
    Apr 2011
    Location
    minnesota
    Posts
    2,070
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    Vee out the crack and weld it. I would personally put a fish plate inside the channel with the ends cut at an angle
    Millermatic 252
    millermatic 175
    miller 300 Thunderbolt
    lincoln ranger 250
    smith torches
    lots of bfh's
    If it dont fit get a bigger hammer

  5. #4
    Join Date
    Mar 2018
    Location
    Clovis California
    Posts
    3,025
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    The good news about cracks is it crack again 👏 repeat work.
    It is a engineering error keeps welders working.

    FYI More engineering is thought and pray 🙏 it works. .Then let's save money cut back on steel more work for welders.

    Dave

    Just look at metal buildings well engineer. Just look at base plate.
    Then custome building I have seen 2" base plate the metal building company used 1/2" plate.

    Ever part of metal building manufactur is engineered
    The custom building uses a outside engineer and not ever part was calculated we just guess. Good luck in a earthquake 😳 ok run fast

    Quote Originally Posted by IslandHD View Post
    Hello,

    I have this crack that I would like to weld. I know how to weld but lack experience to know the best way to weld this crack.

    Do I Weld all sides of it? Do I Need to fish plate it? If so where

    This pictures are not the greatest. I took them in a rush and didnít check them.

    This crack is a few inches from where the box pivot pin is installed. The pictures went sideways when uploading donít know how to fix this!!

    thanks in advance
    Last edited by smithdoor; 3 Weeks Ago at 11:42 AM.

  6. Likes _Weldman_ liked this post
  7. #5
    Join Date
    Aug 2019
    Location
    northeastern PA.
    Posts
    184
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    hello Island and welcome. I can't tell which part is which in the pic, but it looks like the crack is headin to parts unknown. Try to find the end and drill a stop hole in it, vee it out, weld it, grind the weld flush then fish plate it. My opinion anyway. No such thing as a 15 minute weld job.

  8. Likes driz liked this post
  9. #6
    Join Date
    Mar 2015
    Posts
    224
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    I would grind it out get a good v joint jack both sides of crack up till frame is straight weld it with low hydrogen put fishplates in on both frame rails in the same spot weld them in let jacks down

  10. #7
    Join Date
    Sep 2021
    Posts
    6
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    Quote Originally Posted by BillE.Dee View Post
    hello Island and welcome. I can't tell which part is which in the pic, but it looks like the crack is headin to parts unknown. Try to find the end and drill a stop hole in it, vee it out, weld it, grind the weld flush then fish plate it. My opinion anyway. No such thing as a 15 minute weld job.


    here I added some better pictures
    Attached Images Attached Images     

  11. #8
    Join Date
    Sep 2021
    Posts
    6
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    So I should weld the crack on all sides up the sides, and the flange area. Then do I just fish plate the web(side) do I do anything to the web? And do I do this on both sides?

  12. #9
    Join Date
    May 2014
    Location
    Manitoba Canada
    Posts
    4,902
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    So, if I'm looking at this right side up, you aren't actually welding a crack in the frame of the truck, the crack is in the bottom rail of the box where it pivots at the back, right?
    250 amp Miller DialArc AC/DC Stick
    F-225 amp Forney AC Stick
    230 amp Sears AC Stick
    Lincoln 180C MIG
    Victor Medalist 350 O/A
    Cut 50 Plasma
    Les

  13. #10
    Join Date
    Sep 2021
    Posts
    6
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    That is correct not on the truck frame. Box rail/frame

  14. #11
    Join Date
    Sep 2021
    Posts
    6
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    Quote Originally Posted by whtbaron View Post
    So, if I'm looking at this right side up, you aren't actually welding a crack in the frame of the truck, the crack is in the bottom rail of the box where it pivots at the back, right?

    correct

  15. Likes whtbaron liked this post
  16. #12
    Join Date
    Oct 2019
    Location
    Australia
    Posts
    296
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    You might need to clean that up and use some dye penetrant to find the real end of the crack.

  17. #13
    Join Date
    Dec 2018
    Posts
    5,840
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    With channel, there's a "good" side, and a "bad" side. The good side is where you can access it with a grinder.........the bad side is where you can't access it with the grinder.

    V the crack from the good side. Just deep enough to leave a bit of a land to keep your dimensions intact. A full V will cause the thing to contract too much when you weld it. This is a place for a full penetration weld.............but not from the get go. It has to be done in stages.

    Now that you've V'd the good side, grab some 7018 and put a nice surface bead on the bad side. This weld will stay there when you're done, and doesn't need to be ground down.

    After you've welded, you'll see where the slag shows through on the good side you V'd. Use your grinder, with either a narrow wheel, or a razor wheel, and grind down to the bottom of your V until you reach clean metal. This will be the backside of the surface bead you placed on the backside. You've now reached full penetration.

    Then, just fill the V from the good side, and you're good to go. A fish plate is optional. If the welding is done right, you shouldn't need one.

    This was done back in 2017 when I could still see.

    Name:  swap3.jpg
Views: 347
Size:  124.9 KB

    Name:  swap6.jpg
Views: 346
Size:  130.0 KB The bevel is ground leaving some material to keep the original dimensions when the crack was forced closed

    Name:  swap8.jpg
Views: 346
Size:  166.0 KB A weld was placed on the backside. You can see the bit of dark line. That's the slag from the backside weld. The bevel is then made deeper to hit that slag line, and then deepened to get to clean metal (your weld you placed on the backside). At this point, you know you have full penetration.

    Name:  swap11.jpg
Views: 348
Size:  131.0 KB Then simply fill the bevel, and you gotta full pen weld. I like 7018, but any good Charpy rated wire will also be fine.

    So, anyways.........this is the blueprint for getting it done in a good manner. The work I'm putting out these days isn't up to the stuff I could do when the eyes were still functioning right, so don't take recent posts as evidence of the type of stuff I do. Things have changed.............but the principles haven't.

  18. #14
    Join Date
    Dec 2018
    Posts
    5,840
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    The thing about fishplates is................they stiffen an area, and transfer the stress to the ends of the fishplate. We all know that. Sometimes that isn't an optimal thing.

    In your case, it appears that a flange failure caused the crack in the web. There's no real gain in reinforcing the web, when it's been a failure in the flange that caused the problem.

    The stress at the pivot caused a fatigue crack in the flange, and it will probably do so in the future. The base of the pivot probably should have been longer to spread the stress out over a longer portion of the channel. Or, a cover plate should have been welded to the flange where the pivot attached.

  19. #15
    Join Date
    Dec 2018
    Posts
    5,840
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    I'm assuming you're working with channel because I can't see a flange through the crack. Beam would be the same fix though, just a bit more of a PITA if you have to use a burr to V it.

  20. #16
    Join Date
    May 2014
    Location
    Manitoba Canada
    Posts
    4,902
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    I agree with Sam's idea of a repair, but I would still fishplate it on at least one side to spread the force of the hinge over a longer length of the beam. Trying to fishplate both sides might just put excess heat into it. Somebody has been loading that hoist over it's rated capacity ( I'm sure that doesn't surprise you) and if they continue to do so, the other side will likely crack too. Inspect it closely. Check around where the cylinder (or cylinders) push against the beams as well.
    250 amp Miller DialArc AC/DC Stick
    F-225 amp Forney AC Stick
    230 amp Sears AC Stick
    Lincoln 180C MIG
    Victor Medalist 350 O/A
    Cut 50 Plasma
    Les

  21. #17
    Join Date
    Dec 2018
    Posts
    5,840
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    Quote Originally Posted by whtbaron View Post
    I agree with Sam's idea of a repair, but I would still fishplate it on at least one side to spread the force of the hinge over a longer length of the beam. Trying to fishplate both sides might just put excess heat into it. Somebody has been loading that hoist over it's rated capacity ( I'm sure that doesn't surprise you) and if they continue to do so, the other side will likely crack too. Inspect it closely. Check around where the cylinder (or cylinders) push against the beams as well.
    Oh, I suppose

  22. #18
    Join Date
    Mar 2015
    Posts
    224
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    Well I am going to guess but you have little or no experience welding so don’t do something you cant handle having fixed a lot of these don’t make it to tough on the next guy to fix trust me if you don’t know how to fix a truck frame DONT !

  23. #19
    Join Date
    Aug 2012
    Location
    AR
    Posts
    2,074
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    You don't know sammm..............

  24. #20
    Join Date
    May 2014
    Location
    Manitoba Canada
    Posts
    4,902
    Post Thanks / Like

    Re: Welding crack on dump truck box frame

    Quote Originally Posted by Leogl View Post
    Well I am going to guess but you have little or no experience welding so don’t do something you cant handle having fixed a lot of these don’t make it to tough on the next guy to fix trust me if you don’t know how to fix a truck frame DONT !
    Sam wasn't the OP. The OP did state that he is an experienced welder, he's just in new territory. He isn't welding a truck frame, it's the beam on the hoist that sits above the frame. I've seen them welded before, and it isn't as sketchy as welding on frame rails.
    250 amp Miller DialArc AC/DC Stick
    F-225 amp Forney AC Stick
    230 amp Sears AC Stick
    Lincoln 180C MIG
    Victor Medalist 350 O/A
    Cut 50 Plasma
    Les

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 1,634,858,136.22865 seconds with 15 queries