Fix air compressor leaks

[ba_50]

We have a 22 gal air compressor tank that pops a new hole when we plugged the last two.

Is there something that could be put inside prevent it from leaking? This company seems to be out of business as far as parts. Thanks.

[HayZee518]

braze a patch over the hole. the tank wall thickness isn't much so arc welding is out of the question unless it is heli-arced.

[mrcaptainbob]

Tank leaking...l.

Wow. If it were me I'd get a new tank from some other company and transfer the goodies to that. This sounds too dangerous to use any more. What are the chances the patch you do will hold to the max pressure you have it set for, only to have some other weak spot give way. That shrapnel would hurt being far away, worse if you're nearby...

[ba_50]

The whole bottom of the tank is bad. It won't make it to 20#. I am going to check and see if one big plate can be Heli-arced on. We have two other tanks and they are both bad. They all seem to go bad.

[LazyPup]

Any attempt at repairing that tank is at best, courting with disaster.

From you description the structural integrity of that tank is already seriously compromised by internal corrosion. Any attempt to weld a patch on the tank would further compromise it by thermal stress.

Technically speaking, no pressure vessel may be put into service unless it has a current "Hydrostatic Test". If you look on the data plate for your tank you will see that it has three pressure ratings.

1.Maximum Test Pressure
2.Maximum Working Pressure
3.Safe Working Pressure.

Generally the Maximum Test Pressure will be at least 150% of the Maximum Working Pressure. When performing a "Hydrostatic Test" they fill the vessel with water then attach a hydraulic type hand pump with a pressure gauge and they pump the vessel up to the Maximum Test Pressure, then examine the tank for leaks. By testing in this manner should a catastraphic failure occur it would only result in a major leak. (will not blow up)

Once the tank has been certified to the Maximum Test Pressure you are then required to install a safety relief valve that will relieve the pressure if it exceeds the Maximum Working Pressure.

The High limit of the compressor control is to then be set at not more than the 'Safe Working Pressure" limit.

Keep in mind that the pressure gauge on your tank is registering pound of pressure per square inch on the internal tank wall. At 120psi the pressure in that tank is 18000lbs of force per square foot of tank surface. If that tank were to rupture it would be the equivalent of having a stick of dynamite in it.

Legally speaking, no one is allowed to weld on a pressure vessel unless they are a certified welder that has a Pressure vessel endorsement on their certification.

Now I realize that this is a homeowners tank and you are probably not overly concerned by the legalities but consider this, if that tank should rupture and any injuries or death results, you would be automatically liable for all damages, and your insurance will not cover it.

In my opinion it simply is not worth the risk to attempt to repair a pressure vessel.

Now in regards to your complaint that you have had tanks repeated rust out. Generally that is an indication that you are not routinely draining the condensate moisture out of the tank. Generally the small portable type air compressor tanks should be drained at the end of each use, and the drain cock should be left in the open position when the unit is not in use.

[ba_50]

Lazy Pup,

I don't know much about air compressors and wasn't aware they could be that dangerous. Thanks for the information.

[HayZee518]

a disgarded propane tank would make a great tank. wall thickness is about a quarter inch throughout. if you weld [braze] a 1/2 inch hub on it, install a sacrificial zinc anode in it. if rust forms inside at least the galvanic action will deposit zinc over it.

[paul52446m]

Lazy Pup,

I don't know much about air compressors and wasn't aware they could be that dangerous. Thanks for the information.

Lazy Pup info is 100% right. pressure tanks can be very dangerous.
We test steel boilers the same way, fill with water, hand air pump to 1and 1/2
time's the working pressure. Paul