Hobart handler 135 mig

Oil field pipe

I was on a lot of pipe jobs, and with the exception of the 54"OD 1/5" wall that was done with an automated .072" FCAW and argon bug, it was ALL done with 6010 or 6010 + on the root, and 7018 on the rest. This would be for pipeline carrying crude and gas from offshore pipelines to onshore refineries. I do not recall ever seeing a 7010 offshore. With a couple of rare exceptions, it was 6010 and 7018.

Steve

visit my blog at

watch for the book

A fool shows his annoyance at once, but a prudent man overlooks an insult.

Make that 1.5" wall .........

I'd agree with that if you'd said "it can be done" rather than "you COULD ...". Depends on who "you" is.

I've only been welding for 35 years and I never did it for a living like you have. Even so, I've no doubt that I could make a sound weld in 3/4" steel with a 110 volt MIG box. But it would take all freakin' afternoon to do it, so the only way I'd do that is if 110 volts was only power available at the site and I didn't want to haul gas bottles. The practical workshop range of those little boxes is from

24-gage (.025") up thru about 3/16" but I only use mine for .090 and smaller. In that range, it's wonderful. For 1/8" and thicker I prefer 220-volt MIG, stick or TIG.

A very common misconception about welding is that strength depends upon depth of fusion. It doesn't. Fusion is fusion. If the workpiece metal under the deposit of new filler metal is melted, regardless of depth, fusion has occurred.

For single-pass welding, fusion obviously must go to a depth of the thickness of the workpiece, but in multipass welding each layer need only fuse to the metal beneath it.

An experienced welder can get fusion even on thick stock with a small MIG because he knows to watch and manage a puddle. Merely melting metal onto other metal does not guarantee fusion any more than spilling molten solder onto sheetmetal makes a joint. It just makes a splat that is easily peeled off.

Fusion of the workpiece metal usually does happen, whether the operator knows it or not, when stick or MIG machines are run under recommended conditions with recommended filler size for given workpiece thickness. Nobrainer welding can work if newbies will follow the directions.

So, nowadays, are more pipes welded with automatic bugs? It would seem to be the way to go, giving more repeatable results and less labor costs.

i

You are talking about the 20% duty cycle sheetmetal box that Lincoln sells, right? Home depot gets $375 for them. Of course..they are only

20%..but for short welds of uncertain quality..they are adequate.

Ill send you some .060 sheet metal and you can weld it up in a tube for me.

Gunner

One could not be a successful Leftwinger without realizing that, in contrast to the popular conception supported by newspapers and mothers of Leftwingers, a goodly number of Leftwingers are not only narrow-minded and dull, but also just stupid. Gunner Asch

I actually saw another spare tire carrier have the same problem the other day...and for the same reason. Fortunately his didnt come off completely. But another couple miles and it would have.

But inspection showed just about ZIP penetration of the weldment. And this on a nice big commercial dual axle trailer.

Gunner

One could not be a successful Leftwinger without realizing that, in contrast to the popular conception supported by newspapers and mothers of Leftwingers, a goodly number of Leftwingers are not only narrow-minded and dull, but also just stupid. Gunner Asch

Not on 2" material.

Unless you have one BIG assed mig.

And yes.

Gunner

Gunner

One could not be a successful Leftwinger without realizing that, in contrast to the popular conception supported by newspapers and mothers of Leftwingers, a goodly number of Leftwingers are not only narrow-minded and dull, but also just stupid. Gunner Asch

Ayup..that was a typo on my part.

Though I did find 20lbs of 7010 in my recent clean up of my welding rods.

Same as 6010, but 70kpsi?

Gunner

One could not be a successful Leftwinger without realizing that, in contrast to the popular conception supported by newspapers and mothers of Leftwingers, a goodly number of Leftwingers are not only narrow-minded and dull, but also just stupid. Gunner Asch

You're cordially invited to torque my MIG welds at will.

Earlier this year I had to beef up some L's on my trailer. They're MIG welded to the frame and the fenders, hold the fenders on. There are two per fender, oriented at right angles so (theoretically) none of them should bend in vibration while going down the road.

My neighbor usually has the trailer during the winter because he uses it more than I do. When I went over to get it this spring, I noted a bungee cord holding one fender in place. The bracket had cracked in the bend. All welds were sound after 10 years in service, the metal had cracked nowhere near a weld.

I made some heavier brackets, laid them in place and buttered them in with the 220-volt MIG I have now.

I disagree. I suggest that after thickness exceeds a fairly low threshold, perhaps 1/8" in steel, more thickness doesn't matter because there's enough thermal resistance between heat delivery site and cold mass in that (and greater) thickness to allow formation of a puddle in the workpiece with the power delivered by a small MIG. It might take a bazillion passes to weld 2" to 2" but puddle-in-workpiece = fusion = sound weld. Filler-puddle-on-workpiece = pretty-failure.

Penetration is only an issue for single-pass welds and production rate with multi-pass welds. BTW, when I reviewed this viewpoint with Ernie years ago on this forum, he concurred.

I'm not gonna mess with this while the lake is open water, but after snow flies an experiment and demo might be in order. You supply the test coupons, I don't have any 2" stock. I think I do have some 1" bar.

Consider this: with successive passes, try building a "bead" 2" high with your machine of choice. I can attest that I can do that with my MIG because I did exactly that while conducting magnetic field measurements before my ICD implant. I then put the base metal in a vise and pounded the living shit out of the bead sideways with a 4 lb hammer. It bent, but it didn't break or peel away. It was effectively one globby chunk of steel growing out of the 1/4" stock I started with.

There really can't be much discussion about it as arc welding has worked that way since the beginning. In multi pass pipe welding, for example, you may make three passes. Root bead, hot pass and cover. None of the beads except for the root pass penetrates to the inner surface of the pipe and an x-ray film shows the weld as one single layer of metal with no indication of how many passes were made to weld it.

Cheers,

John D. Slocomb (jdslocombatgmail)

IIRC, the original discussion was about a 110v. MIG. I have a 220, also, and I believe like you do that I can crank that baby up, and my stuff will stick. Still, when it goes over 1/4", out comes the 7018, and there's no TinkerToy migging allowed. I can do MIG that will stick, I just prefer to do a better weld with DCRP 7018.

Steve

visit my blog at

watch for the book

A fool shows his annoyance at once, but a prudent man overlooks an insult.

Most people use x rays when they want to properly assess a weld.

Steve

visit my blog at

watch for the book

A fool shows his annoyance at once, but a prudent man overlooks an insult.

Not much argument from here. Only reason for using a light tool for a heavy job is if it's the only tool available. My threshold is

3/8", mostly because I about never have to weld anything thicker than 3/8" and my 220 MIG can do that quite respectably single-pass. I don't like the smoke and slag of stick. I don't weld outdoors much of the year in MN.

No they don't. Some professionals might. I didn't see X-ray machines in some pretty good welding shops I've visited. I know more amateur welders than pros, most of them able to make sound welds, none of us have X-ray kit available.