Air compressor tank repair

[Bryan Rocker]

Can you well repair air compressor tanks? Or is it cheaper in the long run to buy a new tank? There is a 220v 2 hp air compressor which has a hole in the tank. I am trying to determine if its feasible to weld repair the tank or replace.

[Mark Rios]

IMAO, it depends on why the hole is there in the first place. If it was drilled or machined there then it could probably be repaired. But if it's there because of rust or stress of some kind, i.e. bullet hole damage, breakage, etc., then I wouldn't want to take the risk that the surrounding metal was not too fatigued to stand up the the pressure. But again, this is just MAO.

[Paul Kunkel]

You 'could' weld or braize it, but you wouldn't catch me in the same building with it -the pressure is too great. Gererally, unless you can find a good used tank (rare) you'd be better off just buying a new compressor.

[Brian Hale]

IMAO, it depends on why the hole is there in the first place. If it was drilled or machined there then it could probably be repaired. But if it's there because of rust or stress of some kind, i.e. bullet hole damage, breakage, etc., then I wouldn't want to take the risk that the surrounding metal was not too fatigued to stand up the the pressure. But again, this is just MAO.

DITTO!

Brian :)

[Mike Cutler]

What Mark said.

It may not be cheaper, but it may be safer to just replace the tank. Especially if you don't know why there is a hole in it.

[Bryan Somers]

My thoughts are..... Forget it!!!!
Check out my first post about a compresser tank.

http://www.sawmillcreek.org/showthread.php?t=21508

I wish I had taken a couple of pics of that tank but didnt. A compressor tank is a pressure vessle and nothing you want to take chances with. Remember there is alot of energy stored in one and you do not want to be near one if it lets go.

[Vaughn McMillan]

My thoughts are..... Forget it!!!!
Check out my first post about a compresser tank.

http://www.sawmillcreek.org/showthread.php?t=21508

I wish I had taken a couple of pics of that tank but didnt. A compressor tank is a pressure vessle and nothing you want to take chances with. Remember there is alot of energy stored in one and you do not want to be near one if it lets go.
Thanks for the reminder, Bryan. I have to get in the habit of draining my little 16 gal. compressor more regularly than I do now.

- Vaughn

[Allen Bookout]

Bryan,

If you weld it up and put enough pressure in it you just might be the first individual to actually launch something into space. Just make sure that you do not go along with it.

We all know that good welds in good metal will withstand enormous pressures but I would be worried about the rest of the tank, unless of course, it is a fairly new tank that someone drilled a hole in for some reason or another. I don't know why anyone would do that but some people do strange things.

If you know someone who is an experienced welder you might have them take a look. If they are really good they will know right away, after a little grinding, if it can be safely done. If you do not know anyone with the required skills a welding shop or machine shop would be the next stop. A lot of people with a lot of experience around those places.

Good Luck! Allen

[Carl Crout]

I have brazed up several holes in water well pressure tanks (max pressure around 75 psi) but would NOT try it on an air compressor tank...

[Cliff Rohrabacher]

Stick your finger in the hole. It worked for the dutch.

In theory yes. The actual pressure on any given one inch square area of the tank will be that pressure which you see on the pressure guage. Likely not more than 100 or 125 PSI. That means that all any one inch is holding back is 100 pounds.

One hundred pounds of air in open space (not having the advantage of a barrel to increase velocity) isn't going to be able to shoot anything very hard or far and most likely if it fails the seal will simply start leaking and air will hiss out rather quickly.

The real horror in compressor tanks and old boilers occurs when there is a catastrophic failure of an entire seam (opposed to a mere crack type breach) allowing all the pressure to come out over a very large surface area - producing a god-almighty large amount of destructive force. When the seam fails the part it's holding is liberated in a sudden pop.
Often it's the last pop some folks ever hear.

If your hole is due to rust from inside ( easy to tell just look at the edges) Then condem the entire tank - today.

If one little pit grew to penetrate the tank you know there are plenty of others that are boring out right behind that one. God help you if they are all in a neat little row on the weld seam.

The area around weld seams tend to be softer metal due to the heat of the welding.

[Bill Pentz]

My next door neighbor has run a commercial compressor store for thirty five years so when my old Sears developed a motor knock and pinhole leak I went to him for advice. He said get a new one then went on to share how he has seen units shoot through roofs.

His "funniest" story was from his own garage. He was using a blower attachment, went inside to do something and then ended back outside almost in tears. His tired hose had let go right at the end by the blower attachment. That hose beat his new pickup near to death. Fortunately, his insurance company called it a total write off. Anyhow, also make sure your hoses are in good shape and that you turn off the pressure to at least the hose if you are going to be away.

[David Duke]

I've been in the welding business for over 35 yrs and while tank repair is not what we specialize in, I have repaired many compressor tanks throughout the years. As has been stated if the leak is caused by rust forget trying to repair it because there is probably several more spots that are almost rusted through. Most tank repairs I have done have been on mobile units, sometimes when the compressor is dropped on the wheels the wheel brackets get torn from the tank causing a leak these can be welded with no problem.

While I'm not saying its impossible or hasn't happened in the past I really can't see how a simple repair of a small area could cause a catostrophic failure causing a tank "launch". If the repair does fail all I can see happening is a crack developing along side the weld which would only result in a leak similar to the original leak, if this happens it is probably due to excessive stress in the tank and further attempts to repair would yeild the same results.

[Bryan Rocker]

Thanks for all the replies. I am waiting more information from the seller to befoer making any decisions. I still haven't 100% decided I need an air compressor. However should I come across a decent one at a decent price I might add it.

[Ernie Kuhn]

Bryan,
In a previous life, long ago and far away, I seem to remember that pressure vessels are tested at 110% (or more) of DESIGN PRESSURE. My C-Man 5hp 30gal compressor is rated at 125psi max WORKING PRESSURE. Design pressure for the sake of argument, might be around 180psi meaning it was tested at the factory near 200psi. I would not trust a "repaired" pressure vessel unless it was repaired by certified welder to make pressure vessel repairs and, guaranteed. Don't do it. Buy a new one. Too potentially risky.
Ernie

[Chris Padilla]

I'm surprised our own Keith Outten hasn't posted in this thread as I recall he used to inspect these things for a living once. He has many horror stories to tell about them blowing up...very scary stuff!