SpudFiles

hey guys ive been looking for a piston qev in ameica all i see is diaghram valves if you now where to get them please post a link

Why?

the piston ones can take more presure i belive right or the dighram rip burts or tears and it might cause accidentily firing

twizi wrote:the piston ones can take more presure i belive right or the dighram rip burts or tears and it might cause accidentily firing

Whether the McMaster-Carr are diaphragm or piston QEV's, they can still take over 500PSI. How high are you going?

I think you should be more worried about other parts failing/accidentally triggering the pilot valve rather than the diaphragm tearing.

I believe QEVs from Fastenal are the piston type. The look very similar to the ones sold in the UK, and those are practically all piston types.

yes, the qevs by Alpha(sold by fastenal) are piston type, I've had no failures running 700psi in the 3/4" and 1/4" models...

Are parker QEVs diagram or piston because these are

ive orderd a 1/4 a while back in 2008 i think, and its a dighram so u guys dont think it will tear the diagram at unregged co2 presure about 900 psi

They sell replacement diaphragms for a reason. They DO fail eventually even when used by responsible operators who use them at recommended pressure.

Your own call to take it to 900psi, They have been used at unregged co2 pressure and a diaphragm on one has burst at said pressure when it got poked by accident.

Opinions won't make it not burst, If you want to be safe at 900psi use a full bore ball valve after the QEV and open that before firing.

thanks hot wired