Use of sprinkler valves at high pressure

Cannons powered by pneumatic pressure (compressed gas) using a valve or other release.
User avatar
skyjive
Specialist
Specialist
Posts: 163
Joined: Mon May 26, 2008 3:52 pm

So I have a rather unsuccessful 1/2 inch copper piston gun that I am thinking of refitting with a sprinkler valve. The gun fills off 12g CO2 cartridges and uses chamber volume to set pressure (hope my math skills are up to snuff...). So my question is, has anyone taken a sprinkler valve to 150 psi or above? what kind of safety factor will this give me? Would the diaphragm, blowgun, or valve body fail first? How will valve performance be affected? And also, will using CO2 instead of HPA have any negative consequences? I did do a search before posting this and it seems to me as though 150 is pushing it but essentially OK, but I figured better safe than sorry and I'd check it out in this post even at the risk of repeating previous topics. Thanks for your help.
SEAKING9006
Corporal 3
Corporal 3
Posts: 734
Joined: Mon Jun 23, 2008 3:20 pm
Location: Texas

150 is DEFINITELY pushing it, and thats with anything PVC at that pressure. My suggestion is get one as small as they come, and mod it with a fully modded blowgun. If you are open to other valve types, use a QEV. They are common in stronger materials.
Completed projects:
CA1 SMSS Basic Inline
CA3 PDAB Airburst Cannon

Current Project: Bolt action rifle (25x140mm + 1in shot)
TurboSuper
Corporal 5
Corporal 5
Posts: 986
Joined: Thu Jun 16, 2005 1:44 pm
Been thanked: 1 time

I've taken mine to 120 PSI without incident. It says on the packaging not to exceed 80 though, I wonder how big the safety margin really is...
"If at first you dont succeed, then skydiving is not for you" - Darwin Awards
User avatar
SpudFarm
First Sergeant 3
First Sergeant 3
Posts: 2571
Joined: Sat Nov 04, 2006 9:39 am
Location: Norway Trondheim area

i would guess there is a 3:1 marginal..
"Made in France"
- A spud gun insurance.
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Seeing as diaphragm QEV's can well widthstand their 125psi pressure rating up to over 700psi, I would think sprinkler valves are relatviely safe at 175psi.

Unlike PVC pipe and fittings glued together, the valve is just one piece of molded plastic and it's quite thick. It should hold 200psi easy. But the 'phragm will probably be the first to go, it could rip, tear or just overall fail at such pressures, but I doubt it will fail at 175psi.
User avatar
SpudFarm
First Sergeant 3
First Sergeant 3
Posts: 2571
Joined: Sat Nov 04, 2006 9:39 am
Location: Norway Trondheim area

nr_crowley- it is screwed together and the cap has quite big surface area
"Made in France"
- A spud gun insurance.
User avatar
MrCrowley
Moderator
Moderator
Posts: 10078
Joined: Fri Jun 23, 2006 10:42 pm
Location: Auckland, New Zealand
Been thanked: 3 times

Oh right so you think the lid will pop-off?

That's something more plausible but I still think that it will be fine at 175psi. I don't recommend it, but I don't think it will fail that low either.
User avatar
SpudFarm
First Sergeant 3
First Sergeant 3
Posts: 2571
Joined: Sat Nov 04, 2006 9:39 am
Location: Norway Trondheim area

well it is only one way to find it out.. pressure testing
"Made in France"
- A spud gun insurance.
User avatar
Mr.Sandman
Corporal 3
Corporal 3
Posts: 762
Joined: Fri Mar 28, 2008 9:10 am
Contact:

if you do, it put it underwater or under a box filled with t-shirts nah im just messin with ya :D anyways what brand of sprinkler valve is it and instead of using a sprinkler valve spend a cuple bucks and upgrade to a qev so you can take ot to higher pressures
User avatar
Darkside 6ix
Specialist 2
Specialist 2
Posts: 298
Joined: Sun Apr 30, 2006 6:53 am
Location: United States

Well ive never brought any of my valves over 100psi because I have a pump thats being held together by duct tape (not really, but it gives you an idea of how crappy it is) So when I get a compressor, i would like to know how high it is safe to take it
"Dude, if all of the people on spudfiles got together with all of their cannons, we could take over china"
jon_89
Corporal 2
Corporal 2
Posts: 607
Joined: Wed Apr 11, 2007 9:50 pm

i have used mine to 160psi.
User avatar
daxspudder
Specialist 3
Specialist 3
Posts: 300
Joined: Thu Apr 24, 2008 10:22 pm

Ive heard of them being used as high as 350 before. Their construction is rather durable, and the 3/8"thick lid is more likely to split than strip all 8 screws threads, and if its modded, the quality of the mod is a factor(ive blown a blowgun off my valve twice). Most blowguns are only rated to 90psi, and a standard home depot bought watermaster 1" sprinkler valve is rated at 120psi, i personally have taken mine a little over 220, and I think anything under 350(really just pulling that number out of my ass) is safe(doesnt mean im gonna do it)... just remember the really large, flexible diaphragm always has some pressure on both sides, and over 90psi the blowgun will shut slowly, if at all, allowing the diaphragm to re-seat slow enough that 100psi+ pushing down on it wont destroy the seating diaphragm itself. The real failure point is the point in which the pressure pushes the rounded barrel riser through the lower seating diaphragm, which i estimate to be around 400(why i think 350 is safe, but still a guess)
"<I>For dare to be peace, I have to keep at it everyday, da Man doesn't take days off so neither can I</I>" -<B>Bob Marley</B>, day before a performance, a day after being shot in the chest. "<I>If you are the big, big tree, we are the small axe, ready to cut you down!</I>" -Bob again :brave:
Post Reply

Create an account or sign in to join the discussion

You need to be a member in order to post a reply

Create an account

Not a member? register to join our community
Members can start their own topics & subscribe to topics
It’s free and only takes a minute

Register

Sign in

  • Similar Topics
    Replies
    Views
    Last post