What Do I Need To Weld Some Pipe To A Drum?

Consider various possibilities, such as using a flange and bolting the flange to the drum (with appropriate backing and gaskets), or paying a professional company to do it.

The fist alternative could cost you about $15 and would probably work just as well as welding, if you can get the backing positioned inside the drum. Depending on what you do, you can use sheetmetal screws also, provided that there are no stresses on the joint. etc etc.

You would be unlikely to need 150 amps for this application. Our expert, no doubt, will correct me if I am mistaken. Just yesterday, I welded 1/8" plates with 80 amps.

80 amps at 30 volts would amount to 2.4 kW.

You should be able to, but you could also tap into a 240V power, if it is supplied to your house.

Always a great idea...

A disclaimer, I am as far from being an expert in welding, as it can possibly get.

i

"Ulysses" wrote: I want to weld some black pipe, about 3/4 or 1 inch to a steel 30 gallon drum. ^^^^^^^^^^^^^^^^^ Tell us what you are trying to build. It makes a difference whether you are building a barbecue or making piping attachments to carry water.

My first thought is that, if you have no welding experience, you may have trouble due to the difference in thickness between the pipe and the drum walls.

150 amps is output amperage at much lower voltage. I run my 225 amp welder from a forty amp circuit all the time, no problems ever. It will occasionally pop a thirty amp breaker but not very often. Volts times amps equals power, and you can think of a welder as a big transformer which conserves power, so volts times amps on the input side equal volts times amps on the output side. Input side voltage on my little welder is 220V and output voltage might be 22V so I get ten times the output amperage as the input amperage. Very roughly, anyway.

I suggest you look on your local craigslist and find someone local who's trying to make money welding, and pay him a few bucks to weld it for you. Be aware that the cheap little 110V MIG welders they're pushing these days run flux-core wire, and it's real hard to get a nice looking weld with that wire. Lots of guys give up in disgust. A little stick welder would work but it takes some training to be able to use one. Same thing for an oxy/acetylene setup, and if you buy one of those then it's quite a bit to store, and you may have problems with your homeowner's insurance or even local statutes -- o/a welders cause a lot of fires and lots of people are afraid of them.

GWE

Ulysses wrote:

Is your pipe hollow or full ? If it's a water pipe then a good 110 V could do it without any problem. I've tested a 110V welder at the Miller shop on

3/16 inches plate and the weld were full penetration.

Given that your steel drum would be around 1/16 or less thick and your pipe less than 1/8 you would be ok.

150 amps times 120 volts is 18000 watts. We must be talking about a transformer here and measuring the current at that output, right?

What I am trying to build is a wood gas generator. It produces mainly CO gas by burning wood inside an enclosed drum. The fuel is suspended away from the bottom and sides. Whatever I use to join the pipe to the drum needs to be very heat resistant and completely airtight or the generator won't work.

example:

I am interested in buying a welder and learning how to weld because I may make one or two additional units after getting the bugs out of the first one. I'm planning on using it to run a 5000 watt electric generator which could be used to run a welder to make more units etc.

"Ulysses" wrote in message news: snipped-for-privacy@corp.supernews.com... | Greetings. | | I want to weld some black pipe, about 3/4 or 1 inch to a steel 30 gallon | drum. What kind of a welder do I need to do this? I have seen some cheap | arc welders advertised but I have never welded (except a small amount of | brazing) and I have no idea what it will and will not do.

Unless you're willing to commit to the necessary investment of money and time to welding, not knowing if it will be the thing for you, you are taking quite a risk. You'll have to spend a few bucks in change, plus the accessories that may differ depending on the nature of the job. For this kind of job, I'd really recommend hiring it out. If you insist, then I think the least amount of up front expense vs. the learning curve would be to get yourself a torch set and braze it up. Trying to fit and weld up pipe of unknown wall thickness to a barrel with relatively thin sheet metal isn't a task for a newbie on any process. Considering my skill level, I'd be brazing it, even though I think I could gas weld it. The weld would likely be weak unless it was reinforced, though. My stick skills would be blowing holes in the drum all over the place. Brazing with a heavy fillet is plenty strong and not so hard to do. The part that makes it difficult is the thickness of the barrel compared to the pipe. The pipe will take longer to heat up than the thin barrel, so by the time you've got the pipe up to temperature, the drum has melted through. I think that you should avoid the little torch and tank sets at the hardware store. Purchase a torch set, even a Harbor Freight kind will work for you, and rent a set of bottles that you can return with little out of pocket if you don't use it enough to justify the expense of rental. If you like it, spend the money to get some better equipment.

You can also buy fittings made for making pipe connections to drums, if that might save you a lot of expense and hassle right off the bat.

welding is usually done at much lower voltage, for example 28V DC.

i

Most excellent point, and deadly to forget.

Point well taken. I will find out what was in the drums before I buy them.

>

I need the fittings to be air tight and heat resistant for this particular project. Are there any fittings with seals that can resist several hundred degrees?

Here's what I want to build:

Standard plumbing pipe is probably at least 3 times as thick as the drum so from what everyone is saying it will be difficult to weld or braze. I'm not sure exactly how hot it will get during operation but it most likely would be hot enough to melt solder and burn off epoxy etc.

>

I would just use a flange and backing on the other side, and bolts, maybe stainless.

i

This isn't a practical weld (having read what you're trying to achieve).

You need some skill (minimal training and a lot of practice) more than you need a "magic box". Whatever you do get, you should also get yourself an extra box of consumables, a spare weekend and a wheelbarrow load of scrap metal. Take time out and practice your welding before you need to use it for real. Most beginner welders (especially car restorers) screw up because they try to dive straight into the real job first time. Now does that _sound_ sensible? 8-)

IMHE, you don't need much training. Night classes are really good, because you get to use big machines without needing to buy them first. If you're using your own kit though, a book (Gibson's "Practical Welding" is my recommendation) and that important practice on your own is enough to do pretty well for starters.

As to welder types, then obviously you should get all three: gas, stick and wire-feed. 8-) OK, so budget might come into it a bit.

Gas welding is a lovely process and good for neat gas-tight work in thin sheetmetal. It probably is the best process for doing real gas-tight welds in this type of work. I wouldn't want to make exhaust pipes without it. It's also useful (which the electric processes aren't) in that you can braze with it or use it as a heat source for simple bending or forging. My gas-welding kit spends more time rigged for oxy-propane heating than it does for welding.

You _need_ a gas burner as a heat source. Simple propane and natural air torch is cheap to buy S/H (treat it to a decent hose though) and uses cheap gas. Very useful to have around. With a few firebricks you're also on your way to brazing.

Stick welders are great because they're so cheap. If you're needing to weld angle iron together to make a stand or framework, then it's your friend. Great for fixing ploughs, hard-facing digging tools and all sorts of other stuff too. Damn all use on sheetmetal though, which is a great shame.

Wire-feed is what I use to stick metal together, day-in day-out. I've got the others, just never use them. Machine isn't cheap to buy, but it's cheap to run (unlike UK gas prices). It's also the least skill-sensitive and the quickest in use. Read that book and do that practice though!

Now back to your pipe and drum. This just isn't a good candidate for welding. It's a hard weld to do, because the metals are of varying thickness. Also the exhaust from wood pyrolysis is infamously corrosive and it will attack a joint like this in no time. If you weld it, then I'd gas weld it with a big thick fillet that was beautifully smooth and had no voids or penetrations in it. Then it would last fairly well, but would probably rust through at the edge of the thin pipe going into the fillet. If I did it with the wire feed, even with my best skill, then it would still rust through the weld in no time.

So what I'd do here, and for nearly all thin metal joints in woodbunring kit, is I'd arrange for a large overlapping flange and bolt it together with a good layer of stove cement between the flanges. It just lasts longer.

I do make woodstoves. I do it with wire-feed welding, I'm careful about my weld quality and I don't use any steel under 1/8" thick. My "drums" are made from propane tanks, not 40 gallon drums. I just don't think you can use such thin steel here without getting corrosion problems.

I think I would use mechanical attachements as they did here

Interesting concept really and obviously quite functional .. I don't think it would work well on a fuel injected motor though :)

I guess I'm asking the wrong question. In my ignorance welding and brazing have the same meaning--I don't really know what either is.

So, I take it brazing is more akin to soldering but at a higher temperature and with a harder bonding material?

Next question: what do I need to braze some black pipe to a steel drum?

Thanks.

That does seem to be a limitation but it gas gets any more expensive someone will probably figure out how to do it.

Producer gas was also used extensively in Europe for lighting and cooking and possibly for comfort heat and hot water. I think some kind of blower might be needed to make up for the suction from an internal combustion engine for, say, a water heater etc but since they didn't have much electricity in the 1800's there must be a way to get it going without a blower.

I can't get the link to work :-( Sounds like an interesting and my-kind-of sight. I'll try again later...

It sounds like stove cement and flanges would probably work for me and would save me the trouble of having to learn welding or have it done somewhere.

Where do you get stove cement?

A lot of things here that didn't occur to me such as corrosion etc. I had thought of using old propane tanks (old because of the change in valves and they can no longer be filled) but the idea of having to cut the top and bottom off seemed difficult. But this would probably be easy for you with a cutting torch.