QEV Temp Operating Range

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keep_it_real
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Tue Feb 12, 2008 11:59 pm

Does anybody know why this QEV has a lower operating range of 32 F. I looked up NBR seals and it says they are designed for low temperature. It's not a safety issue (valve is aluminum) but I don't want the valve to stop working in a couple fires. I'll be using regulated co2.

http://cgi.ebay.com/Pneumatic-quick-exh ... dZViewItem
EGOed
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Wed Feb 13, 2008 7:33 am

These valves are made in China and are not rated by the same standards that some of the other more well known pnuematics manufacturers use as their benchmarks for performance......Most of the other QEV manufacturers list their lower temp range @ 0 F or lower......You may be better off getting a Deltrol , Humphrey, etc... since they are well known for their reliability and performance.....
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Carlman
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Wed Feb 13, 2008 8:46 am

it would all come down to quality like EGO said, it may be that some parts become brittler at lower temps because of the lack of quality parts used.

and why 1/8" by the way?
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peeeto
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Wed Feb 13, 2008 9:05 pm

you can get a 3/8" Deltrol QEV from McMaster.com for about $12. i'll see if i can get the McMaster part # for you. (BTW, i recently just happened to take a picture of mine before i polished cleaned & lubed - i'll dig that up too).
peeeto
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Wed Feb 13, 2008 9:26 pm

6646K11
Quick-Exhaust Air Valve

3/8" Inlet,
3/8" Cylinder/Outlet,
3/8" Exhaust

In stock at $13.08 Each


p.s. stay away from the 1/4"x1/4"x1/4" QEV for - it's made by Mead (Mead #1B QEV) and i mistakenly bought it - i never used it (gonna return it) 'cause i can hardly blow input air into it & can't simulate quick exhaust by blowing it like i can all my Deltrols. oops that sounded bad. but you know what i mean, dammit!

the 1/4" x 1/4" x 3/8" exhaust is good Deltrol tho - body same size as the 3/8". i have one of those too & seems to work just as good as the 3/8" and if you're trying to economize that one might be better to reduce cost by buying 1/4" fittings instead of 3/8". the pistons might be slightly differnt but performance in triggering a larger 3/4" QEV seems the same.

i find that (at 90 psi), the 1/4 x 1/4 x 3/8 certainly will pilot with pilot pipe/fittings as small as 1/8" pipe and 1/4" OD copper pipe (about if not exactly the same ID's). so no need for 3/8" all around...


p.s. Ed - besides your pb artillery, howcomeyouknowsomuch about pneumatics - work?
keep_it_real
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Thu Feb 14, 2008 4:41 pm

Thanks for the input.

peeto: i can't use the 3/8" Deltrol because I'm limited on space. It should be about an inch wide max. That's why I like the first one I posted.

My other option is a paintball QEV from palmer-pursuit. Unfortunately, that requires more expensive fittings going from godknowswhat to NPT.

Another question due to palmer-pursuit's help depo or lack of it. How do you attach tubing (micro line) to the slip fit below? Is there some kind of collar that slips around it? Kind of a dumb question but...
http://www.palmer-pursuit.com/cart/inde ... 4bb9c26de8
EGOed
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Thu Feb 14, 2008 10:45 pm

Yeah Peeto, I work in a chemical plant where pnuematic instrumentation and valves makes up a major portion of the systems that I work on.......You would not believe some of the stuff that we have there......I am constantly looking for stuff to use on launchers.......LOL......Keep_ it_ Real.....The slip fitting you are asking about are standard paintball gun macro line fittings...You just push the plastic tubing into the fitting and the collar on the fitting locks the tubing in with internal prongs that grip the tubing and prevents it from pulling out when pressurized ... its similar to a compression fitting but can only be used for plastic tubing.......P.s Peeeto I picked up a bunch (11) 3/4 " pulse valves and will give you one when I meet up with you at the paintball field in the spring.
peeeto
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Fri Feb 15, 2008 11:25 am

*drool* oh cool! thanks - that'll be interesting to work with! i'll have to make a mortar next for your field!!!
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