new compressor mit hole

[bborr01]

You made a VERY wise decision not to weld on that tank! As for the suggestions to go ahead and weld it I would strongly suggestion that no one heed that ill advised nonsense that could very well get someone killed, a leaking tank is dangerous and ANY welding only makes it worse, never weld a leaking compressor tank! Even if someone manages to "fix" the leaky spot the fact is that if that spot was leaking due to corrosion then it is just the "tip of the iceberg" and the tank is going to fail in another area soon, the next time may very well be catastrophic. Air compressor tanks do not last forever and developing a leak is a sure sign that it has reached the end of it's service life and needs to be replaced not "repaired". When an air tank ruptures instead of just springing a leak it does so with extreme violence that can, and has, caused serious injuries and fatalities. Most people who would recommend to weld a tank leak have no idea just how much damage a ruptured 60 gallon tank with 125 PSI can do and believe me it can do plenty! Welding on a leaking pressure tank is not making a repair it is making a potential bomb. If the leak actually is due to just a pinhole then in such a rare case as that a repair might be attempted but how could a person possibly know for sure? Short of cutting the tank open it would be difficult or impossible to tell if the leak is just a hole in a bad weld or if it is, far more likely, due to corrosion or fatigue. Corrosion might or might not be visible with a light if a large plug is removed but fatigue, which is as bad or worse than corrosion, will not be visible and a fatigue leak could very well mimic a pinhole type leak in a weld, besides a pinhole should have been obvious when the tank was new. Fatigue in a tank mostly occurs from vibration and cracks usually are found around welds on motor/pump mounts and bottom tank supports (feet). Fatigue cracks can also form due to expansion and contraction of the tank during normal operational discharge/recharge cycles and this is compounded if the tank is left to become completely discharged often. Tanks do expand and contract during operation and they do so to much greater degree than most think.

Boy that sure is hard to read all bunched up like that.

Brian

[Rex]

Here's one such anecdote:

http://www.jalopyjournal.com/forum/s...ad.php?t=69953

[bborr01]

One more thing.

I think if it were my tank and it was at this stage of repair, I would

1. Plug the bottom of the tank

2. Pour a quart or so of paint in it, probably enamel.

3. Roll it around to coat the bottom of the tank from the inside for extra corrosion resistance and to help seal the hole from the inside.

4. Pull plug and drain paint.

5. Let dry.

6. Repeat as necessary, to comfort level.

7. Chase drain hole threads.

All that said, if this were an old rusty tank I would scrap it in a heartbeat.

Brian

[Ken_Shea]

Being cautious, which I am, is not the same as being paranoid, caution prompted me to to limit my 175psi compressor/rated tank to 150psi when I replaced the pump on a 25 year old compressor tank. It also is shut off at leaving.

The link Rex put up amounts to some evidence but certainly not proof, who knows what transpired on the conversion.
Bet that scared the bajeebies out of him

[gnm109]

Being cautious, which I am, is not the same as being paranoid, caution prompted me to to limit my 175psi compressor/rated tank to 150psi when I replaced the pump on a 25 year old compressor tank. It also is shut off at leaving.

The link Rex put up amounts to some evidence but certainly not proof, who knows what transpired on the conversion.
Bet that scared the bajeebies out of him

My tank is rated to run at 175 but when I bought it, the shop had set it to shut off at 150 and start up at 135. I left it that way since I never use more than 100 psi on my air tools, usually about 90 psi mostly. I have no need for 175 psi.

By the way, I took the two bungs out of my tank a year or so ago. The wall is 3/16" thick, IIRC. I measured it with a 1" micrometer. You can get a pretty good look in there with a flashlight when the bungs are out and it's still very clean and free of rust in there.

[Willy]

I certainly won't down play the seriousness of an exploding pressure vessel as the stored energy present can be lethal. I have known people in the industrial tire service sector that have unfortunately have been crippled due to tire explosions at less than 100 psi. Others in the industry have not been quite as lucky.

However given the fact that the tank is new and is probably leaking due to an undercut at the weld near the bung, I would take a serious evaluation of the entire tank before scrapping it, or fixing the tank for that matter.

My first course of action would be to get the tank ultrasonically tested in order to determine if it is worth spending any more time and money on.
For those not familiar with this procedure or equipment I've included a random link to one unit that gives a representative description of the capabilities and applications of the process.

http://www.eesiflo.com/products/eesiflo_tg11_01.html

Actually after having borrowed one from a friend for different applications, it's on my next tool purchase list. They go from $200-$2000 dollars, but do offer a very easy means to do non-destructive testing on various materials.

Next, if the tank passes, would be fixing the tank followed by hydro-testing. This is probably more than than most purchased tanks undergo. As they are manufactured to a procedure for pressure vessels but seldom are they actually tested.

If this is too much in time and resources than you have two choices, either live with the fix and wonder, or buy a new one and turn the old one into a barbecue.

[jep24601]

A hydro pressure test is easy. Test it to 270 psi.

[Ken_Shea]

Not a post on here where any one is down playing the seriousness of an exploding tank, I'm certainly not, so not sure what you are alluding too.

Still, no evidence that a leak equates to a rupture, I believe primarily because there may be no evidence to that allegation, over pressure is the very likely culprit that leads to rupture, just as it did/does in your tire example, there is a reason that the "Do not exceed xxpsi while inflating" is stamped on tires.

Willy, hope you don't drive on tires that are over 6 years old

[Rex]

I spent about 30 minutes googling "air tank explosion" "Compressor tank failure" "air compressor rupture" and several other variations and combinations, both regular web search and new search. I found no anecdotes resembling the conditions we are talking about. What very few failures there were happened to badly neglected, old rusty tanks.
granted, this is far from a scientific study. But if it were a serious danger, statistically there would be some online evidence of some sort.
I'm thinking the manufacturers are not going to let a tank design on the market if their weld joints could fail due to a single welding void. I think worst case the JB Weld may deteriorate before the steel does and it starts leaking agin in 5 years. I can live with that. I've done plenty of things in my life that I consider higher risk.
And if I'm wrong, your next google search on the subject may be more fruitful.

[Willy]

Ken I'm not alluding to anything, certainly nothing that you said.

The tire tire service personal that I refereed to were crippled due to a large industrial tire that had sustained internal damage to the sidewall area which was not visually apparent when it ruptured, the inflation pressure was well below the actual operating pressure.

Just wanted to make sure everyone here is cognizant of the fact that if I were to repair my own tank, (and I have in the past), that I am fully aware of the pitfalls and safe procedures inherent in such an endeavor.

I realize some of the people here are very sensitive about safety, and rightfully so, but I think I am probably more cognizant about the well-being of my own carcass than some dude in a third world country pumping out paper thin substandard air receivers for 6 day, 12 hour shifts.

I know if I screw up that I could be wearing it, the guy down the street that sells the cheap compressors and tanks could care less, all he has to do is file out a warranty card and give my widow a new tank.