air compressor tank welding advice?

[Longbeard]

The compressor shuts off and I hear a leak. I find a crack branching off a weld that holds the compressor bracket to the tank. Anyone made a repair like this before? I've got 7018 and 680 weld rod. Which would be better? I'm guessing 7018.

 

[crash325]

The compressor shuts off and I hear a leak. I find a crack branching off a weld that holds the compressor bracket to the tank. Anyone made a repair like this before? I've got 7018 and 680 weld rod. Which would be better? I'm guessing 7018.

I'm guessing "Don't Weld" it. Just asking for a Real Problem and possible dangerous situation. :2cents:

 

[BIG DOOLEY]

First I woudn't advise repairig the tank.
Second If your like me you'll try.
is it an upright tank?
could you remove the bracket thats causing stress to the metal most likely thru vibration?
vibration and metal fatigue is most likely the cause, there is most likely more fatigue at other locations around the bracket or at other welded areas.
the pump, belt,pully assembly or motor may be out of balance and continued running will cause more fatigue.
you may be able to remove the bracket, drill a hole at the ends of the crack and weld it sufficiently.
Myself i would weld a relief patch over the affected area after to hold the metal more efficiently.
remount the motor/pump on a suspension pad.
I have patched compressors in the past and they are still running 8 years later. but do keep in mind it is not safe due to unseen damage that is not seen to the naked eye.
The safest bet is not to repair it.
Tom

 

[Longbeard]

Yes its an upright. What kind of relief patch? Just a strip of metal across the weld repair i make?

 

[BIG DOOLEY]

Yes, you would clean the metal by removing all the paint.
try to find the ends of the crack.
drill a small hole at each end, this is to try and prevenct the crack from growing any farther.
grind out the crack to bevel the edges on each side of the crack so you can get penetration with your weld along the crack.
grind your weld down to the surface of the tank.
a patch of metal the same thickness of the tank, with the paint removed completely where the patch will reside.
form the metal to the shape of the tank surface and then tack it in place.
finish by welding the perimeter of the patch.
it may be difficult to repair due to the fact that most of the time the bracket is located on the top cap and the surface is not flat.
forming it to the shape of the tank is more difficult there.
Once again it is better to look for a replacement tank from a shot compressor due to unseen metal fatigue/cracks.
this is the outcome when one releases. it is not always a small leak.
best to look for a newer tank, and solve the vibration problem.

 

[crash325]

Yes its an upright. What kind of relief patch? Just a strip of metal across the weld repair i make?

I get the impression that you are not real experienced welder or metal man. If I am right and you just have to repair it, at least get someone to do the repairs that has more experience.

Best is still, get a new tank. Learn to weld & metal work turning this tank into a bar B Q or smoker.

 

[BIG DOOLEY]

I've added a few more pics
Tom

 

[Longbeard]

Actually I have been welding for 30 years just never welded a pressure vessel. Well I Did but much larger and with a dual shield flux core. I'm just looking for advice and I'm very aware of the dangers. I'll see if I can air arc the crack out if my smaller compressor will keep up.

 

[CBW1999]

Danger Will Robinson.....DANGER.

Fixing that is a realy bad idea. the tank has told you that it is no longer capable of holding pressure- listen to it, please.

From your description, this isn't a weld failure but structural failure.

 

[Shield Arc]

First question you need to ask your self.........Hows your home owner's insurance? Second question you need to ask............ How good of a relationship do you have with your insurance agent?