Butterfly valves

[alkalineall]

I did a little bit of searching and couldn't find any discussion of butterfly valves used in gun designs. From the few that Ive looked at online they seem perfect for my what I need to do, and are available in huge diameters Does anyone have any experience with using this type of valve either to pilot a piston or stand alone? Thanks

[jrrdw]

Swimming pool filters use these valves, they held back 65psi with water in it, but was hard to open. I would hand test them rite off the shelf before spending money on them!

[Infernal Maveric]

Well, in an episode of "Mythbusters", Jamie and Adam used a 10" or more sised buterfly valve when building their chicken gun.

It was a pnuematic gun that used a huge boiler for the chamber and like about 9-12" or so diamiter of pipe for the barrel.

To open the butterfly valve they used a huge weight to slam down on the valve handle.

This would lead me to beileve that a butterfly valve would be hard to open y hand.

[clide]

Most pumpkin chunkers use butterfly valves, although the guns are HUGE to make up for the slow opening speed of the valve.

[schmanman]

on mythbusters, the air chamber was a huge air tank from an air compressor, not a boiler.

[beebs111]

but butterflys are really good in 2-3" valves because they have a ton of flow with little restriction

[frankrede]

Butterlfly have the best flow.
They may be ahrd to open but as soon as you do it will open far better than most valves.
Check mcmaster they have lots of sizes and they also have electricall operated butterfly valves too.

[alkalineall]

Cool, yeah as far as flow they have to be one of the best options around. once the opening is started I would think that the gas flow around the butterfly or plate or whatever you call it , would help to assist open it fully. But I don't could be wrong.