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I have a modified Super Cheap paint pot for Casting. I pressurise to 50/60 PSI, but it drops to 20 PSI quickly. It has been suggested that the safety valve may be the problem. Have tried the soapy water test leak test but no luck. Any suggestions are greatly appreciated. Luckily I haven't had issues with bubbles as I have had casting without the pot.
I removed the safety valve as once the pot is to the pressure of 50 PSI I disconnect the pot from the compressor.Quote:
Originally Posted by daryl1
The safety valve is really for when it is used for its original purpose of painting whilst connected to the compressor.
Peter.
There are many places it could leak from, not just the relief valve. Use your soapy water on all the joints.
It can also leak from the gasket under the lid so turn it upside down and put your soapy water in the cavity that the lid creates. If it is leaking from the lid gasket it could be leaking over a fair area so the pressure would drop quickly and there would be hardly any sound of air escaping. If it is leaking from the gasket it might be just a case of tightening the clamps down a little firmer but don't go overboard. If you tighten while in the inverted position with the soapy water still there you will be able to tell if there is an improvement.
If it is leaking at the rubber gasket because it is old and hard, pull the gasket and boil it in water for quite a while until it softens up again.
BTW there is never an excuse for running a pressure pot without the safety valve fitted and tested. You never know when something unexpected will happen and it is the only thing that will keep you from leaking all that red stuff that you are so fond of keeping inside your skin.
If you dunk the pressurised pot in something like a garbage can full of water it may be easier to detect the leak/leaks .
Ted
Found that the main leaks were coming from the lid seal, so I took it out and reversed it. Looks like it is sealing now. Only need to put some thread tape on the safety valve union to stop a small leak.
I thought those Superchaep tanks had a safe working pressure of only 45psi. DO NOT exceed their safe working load what ever it is, they are not the best of tanks, and go with a real bang when they fail.
Stamped on the lid is "DO NOT EXCEED 80 PSI"