What's new
What's new

Welding 3" OD pipe to 1 !/2 OD water pipe.

Sophiedoc

Cast Iron
Joined
Jun 12, 2004
Location
Missouri
THIS IS FOR A CATTLE FEEDING AREA.My friend who has moderate welding experience welded these together with a motor driven stick welder at right angles to one another.Cattle "jostling" broke all the welds.He blames the lack of purchase of the juxtaposed convex surfaces for the failed welds.Best way to get more contact area?
 
Purchase or make a saddle template.

Cope pipe on a mill.

Cope pipe with torch old school, set pipe on the pipe to be saddled at the angle wanted and using your torch follow the contour of the larger pipe

and trim til it fits.

also works when both both ends need saddled to cope one end and than cope the second one in place, bump into place and than triming to fit.
 
5.jpg


Might want to use a press, but all sorts of livestock fencing has the ends 'smashed'.
 
jamscal has the right idea. Fancy work may pay better but for cattle this is a get-r-done job. You may also want to check over your friends welds and technique. Chances are there is as much problem with the weld itself as there is with the fit-up.
 
Smashing the ends with a hydraulic press or large hammer seems OK for the ends but my shop is small and we can't get the middle ones to the anvil or hydraulic press because of pipe length.Would an arbor press that is portable provide enough oomph?-thanks all.
 
To make smashing the ends closed, apply heat with a torch, the do the hammer work.

And find somebody that can weld. Even bad fit-ups can be welded, if the materials are proper.......since all the welds broke, maybe the verticals were cast iron soil pipe?
 
My guess is, this is scrap material- so junkyard steel rules apply- ie, he has no idea the carbon content, or type of steel, and probably, what would be the right stick to use.
If it really is "pipe", that is, regular old schedule 40, then most common welding rods should work fine, assuming sufficient amperage, and a good weldor (thats the person- a welder is a machine).
But what if its some wacky drill tube, or something else, that needs preheat or some fancy rod?

First guess- crummy fitup, not enough amps, and probably not the right deep penetration rod for rusty, dirty, junkyard steel. Did he use 6010? If not, he should have.
 
First guess- crummy fitup, not enough amps, and probably not the right deep penetration rod for rusty, dirty, junkyard steel. Did he use 6010? If not, he should have.

Agree with all of the above. 6011 would be just as good as 6010 for this steel, and around here it would be cheaper.

If the pipe is galvanized, grind that off before welding.

Takes a lot of oomph to flatten the ends of Schedule 40 3" pipe--locoguy has the right idea with the torch.
 
Plus 2 what Ries and Sea Farmer said...

I would only add that although 6010 and 6011 are the weapon of choice for dirty metal in the hands of a SKILLED WELDER, alas, I am not wunnadem. Assuming I can get the metal clean I've had much better luck with 7018. I run it really hot and lay down stringer beads. Because I'm able to rest the rod on the work it helps steady my hand. By pushing the rod into the puddle and sort of twisting or torquing it into the direction of travel as I push I can consistently lay a beautiful, shimmering, and perfect bead. I can run 7018 and 7014 this way and even though I'm running hot as a firecracker I don't get undercut and the weld really sinks down into the joint. The wetting and penetration are apparent and the bead is as pretty as a tig weld. Of course it's hard to do that if the fit-up is poor. If it is, I can lay down two beads and then bridge them with a third. Being self-taught this is probably not a kosher technique.

But it works for me!

V
 
I was thinking 7018 for a job like this too...3/32, not 1/8". Don't have to run it quite as hot as the 1/8". Maybe a couple passes here and there. I might use the 6010 to tack since it arcs so easy, then see how a bead lays down...but imo it might be too hot for pipe like this... jmo...
 
Don't forget magnetism

If the pipe has ever been in the ground, used, it may be magnetic. Magnetism fights the arc/bead and you get shit for penetration.

Test this by seeing if a welding rod will hang from it, if it does you need to degauss the pipe. The field way is to wrap an extra set of leads around the pipe and apply current until the welding rod drops off.

I'm 99% sure this isn't your problem, but figured I'd toss it in.
 
If you are talking barnyard technique here, where the welding rod may be older than the pipe, you can weld a piece of angle iron to the end of the 3" pipe then lay the smaller pipe in the angle and weld it lengthwise.
 
6010 is the pipefitter's choice for root passes with a DC welder, and then usually 7018 for cover passes. For this kind of welding, 6010 (DC) or 6011 (AC) would probably be perfect. 7018 doesn't like a low open circuit voltage (about 40 volts) welder (Lincoln buzz-box or equal), but it does great if you have about 80 V open circuit voltage. With low voltage, there's a very fine line sometimes between welding and sticking.

Also, you can get by with older 60XX rods, but 7018 likes to be bone dry. Any rod works better when it's dry, but more so with any low hydrogen rod.
 
Prior to starting this thread I had made several angle iron support pieces with half moons cut out to fit the larger pipe,then welded this on the larger pipe so as to create a cradle for the smaller pipe and then weld to both the angle iron and the large pipe.Seems to work but slow going and thought something would work with less effort and I will try some of the ideas presented-thanks all.
 
6011 is king of the mountain for us in this application. Been there done that every week for the last 7 years. In the field chassis/trailer repair for the largest shipper in the world. In a perfect world 7018 is great, but when its dirty, rusty, or raining 6011 is my rod of choice. Simply has good bite. Now 6010 even more aggresive but requires a big welding machine. A farmers buzzbox will not do 6010 justice.
 
Contrary to somebody's comment above, 6011 runs fine on DC. Can go electrode positive for greater penetration, or electrode negative if you're burning through whatever this pipe is.

7018 is a great rod but without an oven you probably don't get the full benefit of it, especially if you don't use the whole box in a few hours. Local supply house here provides it in packages that don't seem air-tight to me, so I doubt its at full strength even when new that way, without drying it out.

And I'm betting you're recycling the old broken pieces as well, so careful prep is a PITA. I'd stick to 6011 for this one. With a nice joint and clean steel I have sometimes used 6011 for the root pass and 7014 over that, but seems like overkill for this one. ghent is right, this is a get-r-done job.
 
If your pipe is not complete junk and your weldor knows what he is doing, 6010 (preferred by me) or 6011 is the rod of choice. He should be able to run 1/8" rod at 100-105 amps*. I personally would take the time to saddle the post tops and not smash them. That is a matter of pride in workmanship for me. The smashed pipes, IMO, look like a half*** job. Not to mention, at least around here, they are the fences that get repaired most often because the weldor, 1- Can't fit pipe and 2 - Can't weld it when it is fitted. So they choose to smash the post tops and try to make an "overhead", I use the term very loosely, weld on a flat surface.

*your welder settings may vary, mine runs great at 100-105.

Chris
 








 
Back
Top