quick question; check valve as firing valve

[Kilash]

Hey guys, at lowes now and want to know your thoughts on modding a 2 inch pvc valve into a firing valve. Basically im gonna put the check valve in reverse, and put in a slide bolt to keep the check disc up against its seal to keep air in the chamber.

[cammyd32]

What, so like some sort of internal hammer valve?
I tired that once, in theory it should work, but those check valves are really more for liquids than anything else, and I found the moment you try pressurizing the reverse side with gas they start leaking like a B*tch,
Try it by all means I was using 3 year old valves, so you might have more success than I did, would be interesting to see it work

[Kilash]

Yea i thought about that, so i was thinking maybe i have a screw bolt that i can adjust pressure on the seal disc. My working pressure is 70 psi.

[jor2daje]

if you assume the opening is 2" (its most likely a bit bigger) then you have over 3 in^2 of area being acted on, at 70 psi thats over 200 lbs that your bolt or whatever would have to support. Even with enough force the valves are designed to seal with back pressure so it may behave like cammyd32's.

Also Im not sure the exact design of the check valve but if it just slides back and forth then even when open the piston will be in the way and disrupt flow.

Not saying its impossible, just consider the forces and the design but your bolt and trigger will have to be pretty beefy.

[Technician1002]

The valve is plastic. The question does arise on how you plan on opening it against pressure without breaking it. Hammer and PVC is a bad idea. Huge small point force is another bad idea.