QEV Help

[ShowNoMercy]

This is most likely a dumb question, but the QEV I got has two pilot ports so I figured I would use one to pilot it and the other to plumb my air source into. But now I am thinking will it trigger if I use a constant air source?

[clide]

Do you have a picture of the valve? The valves that I have seen that have 2 ports on the lid actually have a smaller valve used to exhaust the main valve, so one of the ports is actually an exhaust port.

[ShowNoMercy]

I added two pictures for you. What do you think?

[clide]

Yep, that is actually a second valve to trigger the main valve faster, the vertical port is where you would put your blowgun or whatever trigger valve you use and the other port with the red plug you would just leave open because it is an exhaust port.

Also that valve will probably work being filled from the chamber. Did they say the brand? If it is Goyen then it probably isn't actually a QEV (although just as fast) and it is actually designed to be filled from the chamber.

[ShowNoMercy]

Its an Asco I believe.

[clide]

Ah yep, I just found that on the Flex-Kleen site, but based on the application I am pretty sure that it fills from the chamber.

[ShowNoMercy]

Ok so I need to fill it through the chamber and then what about my original question? Do I need to turn off the air supply between shots?

[clide]

It will certainly trigger, but I'm not sure how well it will re-close. It will depend on your chamber size and input flow rate, you'll probably just have to try it and see.

[ShowNoMercy]

Ok well I will let you know when it gets here, hopefully this friday.

How loud are QEVs? I have a 36 inch barrel as of now and I want it to be relatively quiet, so am I going to build a silencer?

[Velocity]

QEV's are very good valves, and therefore can be very loud. With a 36" barrel, it will probably be pretty loud unless you make a small chamber (C:B ratio in the neighborhood of 1:1 or below).

And yes, you do fill from the top port (I believe that it was clide who helped me with this problem years ago on spudtech...).