compressor tank repair.

[metal1313]

so i just found a great, smokin deal on an ir 5hp 60gal compressor. it fits my needs well, and for the money it cant be beat even if i eventually replace it with a 2stage.

but there is a major issue, the tank has a pin hole leak. how would one fix this?? could i gaul out the pin hole, and weld it, but is the general opinion that if there is a leak, prob caused by rust. that i should just replace the tank/pass on the deal??

 

[79firebird]

I would never repair a tank if its a real good deal i would take it even just for the head and motor and put it on anouther tank

 

[ears]

so i just found a great, smokin deal on an ir 5hp 60gal compressor. it fits my needs well, and for the money it cant be beat even if i eventually replace it with a 2stage.

but there is a major issue, the tank has a pin hole leak. how would one fix this?? could i gaul out the pin hole, and weld it, but is the general opinion that if there is a leak, prob caused by rust. that i should just replace the tank/pass on the deal??

Yes, you dont repair rusty compressor tanks. You can find tanks for a few bucks to $100, although not super common there are a lot of them out there.

 

[tatra]

the pin hole is probably a tell tale hole that is drilled half the thickness of the material................temporary repair can be made with a self tapping screw...........if it is a tell tale...........if it is not a tel tale then it is probably a thinner gauge and should not be repaired..........the screw repair is like i said a temporary repair until you get a new tank............and keep in mind that if you decide to go this route and it blows out ubder presure you have no one to blame but yourself...........this is a temporary repair only.........................and the reason i repeat it is because anyone that has any common sense trades wise wouldn't have to ask about repairing it...........replacement is necessary.............i mention the preceding repair as i had a situation where a tell tale blew out on a long weekend and this was the only option to finnish the job.......for safty i piled boxes and such around the tank and turned down the pressure until i could replace it...........google air tank failures............i repeat, replacement is the best option

 

[Joe69]

Some settling may occur during shipping....

It just aint worth it. replace the tank. When a pressurized tank fails, it could be like a bomb going off.

Joe

 

[WVU Tuba Dale]

Keep the pump and motor, scrap the tank, and buy a new tank if it is that good of a deal. Don't repair it, your life is not worth saving a few dollars.

 

[Shadowdog500]

I had a friend who had a tank on a 30 gallon horizontal tanks blow out while he was in the next room. He said it sounded like a bomb going off. I agree with everyone else, and I would look into getting a new tank pronto.

Someone posted a link a while ago about someone getting killed when one blew (see photos of the damage):

http://www.cdc.gov/NIOSH/FACE/stateface/ca/05ca010.html

Chris

 

[mad57]

Just replace it with a p..v .c tank.

 

[D.J.]

OOOO mad57 you just had to go there didn't you?
________
WENDIE 99

 

[rickairmedic]

Metal you dont say where you are located but if you are close by I have an 80 gallon tank your welcome to it is an OLD tank but it holds air fine and is probably built better than half the tanks out there today ( the sucker is just plain HEAVY ).


Rick

 

[Torque1st]

One pin hole means there are others just waiting to happen in the future.

Replace the tank.

 

[metal1313]

this is what i figured, and hell theres no way i would weld it myself, i am going to look at it tomorrow to see where the leak is, if i get real lucky it might be a bad thread on the tank drain.

and yea i have some common sense, id try to find a new tank asap, prob before i even hooked it up.

btw its well south of 200bones

 

[Torque1st]

No certified welder would weld the tank for you anyway. The liability and the law would stop them. They should know the regs for welding on pressure vessels.

 

[930dreamer]

I found a new Atlas Copco 120 gallon receiver tank on ebay for $85, mix the old and new. 930

 

[DannyG]

Yeah, definately another tank, scares me just thinking about it.

 

[metal1313]

ive already been searching for tanks, i found a few, but they are either huge, or ancient and look to be in horrible shape.

although if anyone wants a 200gallon tank there is one literally down the street from me haha

 

[brownbagg]

i welded a pin hole about ten years ago,it hold fine, the tank not going blow up.with only 150psi in it, and if it does have more pin holes, they will be the safety valve to pop before it blows. Go ahead and weld it

 

[ZRX61]

...for safty i piled boxes and such around the tank..

All that accomplished was adding additional shrapnel....

 

[Wow]

i welded a pin hole about ten years ago,it hold fine, the tank not going blow up.with only 150psi in it, and if it does have more pin holes, they will be the safety valve to pop before it blows. Go ahead and weld it

BZZZZZ....WRONG! Bad advice! If there is one rust hole there is more! Rust does not only attack one pinpoint area on any peice of metal, it attacks the hole thing. The pin hole is where the rust was the worst, radiating out from that it will be quite thin inside as well. Also you can't simply "weld over" rusty metal to repair it. It doesn't work that way.

Furthermore if there are rust holes in an air tank, it proves that it wasn't maintained very well...another indicator that you don't want it. An air tank will easily last you 100 years with proper maintainence...

 

[Charles (in GA)]

i welded a pin hole about ten years ago,it hold fine, the tank not going blow up.with only 150psi in it, and if it does have more pin holes, they will be the safety valve to pop before it blows. Go ahead and weld it

Air is compressible, it is stored energy, it can easily blow up completely. Lets say you have a ring of rust around the bottom of the inside of the tank due to standing water inside. Lets make a reasonable assumption that the surface area of the inside of the tank from the rust line down is 2 sq/ft. That is 576 square inches. Now, lets put 150 psi on that (my compressor is two stage so it has 175 psi on it). thats 150 x 576 = 86,400 lbs of force on the bottom of the tank (thats 43 tons if you are not inclined to math)

43 tons!!!, now, lets add a little rust to the tank and see what happens when that bomb goes off. It don't just "pop"!

As far as the safety valve, it is designed to relieve EXCESS pressure in the event that the pressure switch sticks and the pump doesn't shut off at 150 (or 175 or whatever). Mine is a 175 shutoff with a 200 psi relief valve. Now, again I say, lets put 43 tons on that tank at 150 psi, and lets see what the relief valve does...... NOTHING, because it isn't designed to......................................

Sorry brownbagg, if you are being serious, this has to qualify as the most outrageously insanely unbelievably scary information I've seen on this board in all of 2009. (I'm being polite here, I wanted to say stupid, but just couldn't get the heart to).

Charles

 

[sberry]

I agree with these guys, no reputable shop would repair it, I wouldn't do it for a customer. Its definitely not an amateur DIY job.

 

[Shadowdog500]

This is what it looks like after a tank explodes! Someone was killed in this explosion! I would not play games with the tank by trying to weld it.

Chris

 

[gorilla]

i welded a pin hole about ten years ago,it hold fine, the tank not going blow up.with only 150psi in it, and if it does have more pin holes, they will be the safety valve to pop before it blows. Go ahead and weld it

Brownbag, Do you play Russian Roulette also?

 

[krooser]

I'd weld it... but I'd inspect it first. Grind off the paint and take it to your local automotive machine shop and have it sonic tested. They can tell you the thickness of the tank... any thin spots.

I used to sell heavy trucks/trailers and we sold many vacuum tank trucks and pneumatic tank trailers over the years. Many had corrosion or leakage problems. We took them to Stainless Tank Corporation in Sun Prarie, WI. They'd sonic test the tank and repair any rust or damage... it's done everyday in the transportation industry.

You don't toss a $100,000 trailer just because it needs to be repaired... but it does need to be done right.

 

[brownbagg]

my point is, if they one pin holes then there other, so they are the safety valve, that tank blew up because the compressor did not turn off. 150 psi not going shattle a tank. that tank blew if it was brand new tank.

 

[gorilla]

If you feel that you must repair this air tank, Please for your own safety have it hydro tested after you weld it. A new ASME air tank costs about $300,00 from WW Grainger (cat.# 395) at this price it seems to me that the testing needed to be safe would cost more than a new tank.

 

[Shadowdog500]

My motorcycle gas tank had rust in it. I used a three step process called POR-15 to stop the rust and coat the tank with a sealer. Anyone here try coating a tank before it rusts through to keep it from rusting through in the first place? My current tank is about 25+ years old, And the water does come out brown.

Chris

 

[Mickey_D]

The report indicates that the car wash tank failed because of improper maintenance. They used the wrong oil in it that caused an explosive fume buildup that ignited from hot carbon deposits. But it does not mean that welding up an old rotted tank is still not a good idea. The best thing to do with a rusty one is turn it into a smoker or BBQ pit.

 

[Wow]

my point is, if they one pin holes then there other, so they are the safety valve, that tank blew up because the compressor did not turn off. 150 psi not going shattle a tank. that tank blew if it was brand new tank.

That is so wrong I don't even know where to begin explaining why. Let me put it this way: What you are suggesting is extremely unsafe, extremely stupid, extremely wrong, and could KILL somebody. Oh yes, 150 PSI can blow a tank that some idiot tried to repair.

Unless you bring in a tank that cost $100,000 like somebody else posted, NO professionall would fix it for you, most would probably laugh at you for asking.

Do you, by chance, have old PVC air lines too, brownbagg?

 

[Torque1st]

That is so wrong I don't even know where to begin explaining why. Let me put it this way: What you are suggesting is extremely unsafe, extremely stupid, extremely wrong, and could KILL somebody. Oh yes, 150 PSI can blow a tank that some idiot tried to repair.

Unless you bring in a tank that cost $100,000 like somebody else posted, NO professionall would fix it for you, most would probably laugh at you for asking.

Do you, by chance, have old PVC air lines too, brownbagg?

Brownbagg certainly advocates using PVC air lines so he must have them.

Krooser- The cost to have a small tank repaired by a certified welder even IF they would do it, and have it tested and certified is prohibitive for a small tank. On the other hand, it may be cost effective to fix a $100,000 transport trailer.

 

[tcianci]

While a pressure vessel of the size being discussed here is probably cheaper to replace than to properly repair, I find it odd that there are so many instances of tanks with pinholes in them. My buddy even has a nice twin tank Hitachi compressor with a pinhole in the tank. Since there are many instances of tanks with pinholes in them, those instances are obviously ones where the tank did not blow up. Usually the indication of a tank with problems is not an explosion but rather a leak. This guy should just go looking for a new or used tank, but don't get everyones pantys in a knot thinking that their compressors are just going to detonate without notice....That reminds me...2010 is coming up, I think that's the year I'm supposed to drain the tank and oil the air tools.

 

[Wow]

This guy should just go looking for a new or used tank, but don't get everyones pantys in a knot thinking that their compressors are just going to detonate without notice....

I don't think anybody is doing that...if your tank gets a pinhole that is your "notice" to stop using it. If your tank is in good condition then you don't need to worry about it blowing up anymore than worrying about dying when you fly in a plane...

PS - has anyone seen the multiple Mythbusters episodes where they blow up household water heaters? Their tanks are about the same as an air tank - designed for around 150PSI max - tested to around 300PSI. The difference is they are full of water, which is relatively safe under pressure, that's why they use it to "hydrotest" air tanks. But if you watched what Mythbusters did to those water heaters, it didn't take much to BLOW AN ENTIRE HOUSE UP...and that's with water. The results would be worse with air.

 

[Torque1st]

I have had tanks with pinholes also, they leak. I have seen some that were repaired with the screw method mentioned above. ASME pressure vessels are designed with a corrosion allowance. When that is used up as evidenced by pinholes just replace the tank. Remember the life that is lost may not be your own.

 

[tcianci]

Also note that you can use a couple of smaller tanks to equal the 60 gallon capacity, that may help you to find some stuff that keeps the whole project in line with being a smokin deal.

 

[tatra]

nobody seems to have mentioned that there are tattle tale holes on higher quality, thicker tanks......... consumer tanks out there are too thin for tattle tale holes so as soon as there is a leak, discard and retank..........the screw method has worked for me as there was a fair amount of parent matierial to allow a good bite for the threads..........again this was done as a temporary repair only..............any one have some info on pressure tank thickness/gauges ?..............

 

[Wow]

Also note that you can use a couple of smaller tanks to equal the 60 gallon capacity, that may help you to find some stuff that keeps the whole project in line with being a smokin deal.

Another relatively cheap source for SAFE air tanks is propane tanks. They are built much thicker and for higher pressure than any standard air tank. Problem is they don't have a water drain valve, so you have to mount them upside-down. If you unscrew the "OPD" valve on top of a normal propane tank, you have regular 3/4" threaded fittings.

 

[Torque1st]

If you have the $$$ to spend you can get the pressure tank standards.
http://www.asme.org/

 

[Kevin54]

If the tank has one pinhole it can be fixed. I've seen other tanks that have had a plate welded to the bottom to repair a few pinholes. If per chance the tank would decide to blow, it will blow at the weakest spot which is at the bottom where the water lays and other pinholes are at. It will not explode and take out half of the garage or go off like 4 sticks of dynamite. You won't have shrapnel going through your walls and sticking into the neighbors house. What you will have is a small blowout and a sudden drop in air pressure. I've seen tanks repaired with a can lid and JB Weld that has held for years.

That is so wrong I don't even know where to begin explaining why. Let me put it this way: What you are suggesting is extremely unsafe, extremely stupid, extremely wrong, and could KILL somebody. Oh yes, 150 PSI can blow a tank that some idiot tried to repair.

Wow....have you ever first hand seen an air compressor explode? I'm not talking the MythBusters episode on the water heater tank but an actual tank let loose. I've seen them let go on a repair. The first thing that gets said is "well ****.....that didn't hold. Have to get a new one now".

You take a GOOD tank, remove the safety valve and put in a solid plug, start pumping it up past the manufacturers capacity, then you will have something to go boom.

 

[brownbagg]

so if a tank blows, its not because of the weld but the rest of the tank is bad, so how can welding hurt the tank, it cant, but like the last guy said, JB weld it or even solder or braze it, I still believe 150 pounds not going blow a tank, more like 400 or greater. so since I am allowed an opinion, I feel nothing wrong with welding pinholes

 

[Joe69]

The heat from the weld can change the structure of the metal around it. Ever see a crack next to a weld?? Especially if the metal is already comprimised, ie. rust.

Joe