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Schrader Pressure?

Posted: Fri Apr 25, 2008 12:13 am
by FordGtMan
Hey, i was wondering what sort of pressures would be suitable for a regular schrader valve, and what mix it could be taken up to. This is the one i am talking about...
http://www.acehardware.com/product/inde ... rader&sr=1

I know they have high pressure schraders at mcMaster, but they are like 40 bucks... :shock:

Posted: Fri Apr 25, 2008 12:36 am
by jackssmirkingrevenge
All the schraders I've ever used were mostly taken from bicycle inner tubes, and I've taken them to 400 psi and beyond without failure so far.

Posted: Fri Apr 25, 2008 12:44 am
by FordGtMan
So they should be able to take extreme mixes without failure? How much pressure is generated about in a 10x mix? I plan on having a mini hybrid with all parts rated to at least 1000psi. The schrader is just making me wonder a bit though. is there any other schraders that can take that sort of pressure?

Posted: Fri Apr 25, 2008 1:07 am
by jackssmirkingrevenge
I'd be comfortable using one in that application - in any case, if it fails, it's easy to screw out the stem and replace it.

Posted: Fri Apr 25, 2008 1:11 am
by FordGtMan
Oh and by the way JSR, how were you planning on filling your hybrid project with a syringe? did you have a special valve or just open and squirt it in... ?:D

Posted: Fri Apr 25, 2008 1:13 am
by THUNDERLORD
My suggestion, You could check with a local Heating and Air conditioning (HVAC) shop.

Not sure the maximum but they definately have higher pressure stuff.
Just look up a local one and call them on the phone and you can check prices also.

They also carry various pressure tank, regulators,welding gear...
It shouldn't be to hard to explain what you need without them finding out your a "Spud freak" (Joking)

Posted: Fri Apr 25, 2008 1:18 am
by FordGtMan
It shouldn't be to hard to explain what you need without them finding out your a "Spud freak"
Thats why i hate asking people. They will never understand, this great hobby... :D

Posted: Fri Apr 25, 2008 1:39 am
by THUNDERLORD
Oh some of them have the same hobby.
But anyway, what I meant was to think about your questions and phrase them in simple form like "I need a shrader valve that can handle ---psi, do you have that?" or "what's the highest rated shrader valve you have?"

or if it's not enough just state that you need it for higher pressure.
Most of them are busy and will just be professional and helpful.

If you call and keep it simple you can get the part # information and go in and tell them you want that part. If that fails, tell them it's a school or vocational project. They should be helpful.

It's a pain having to design around parts manufactured for other stuff but you can find shrader valves and lots of parts in HVAC supply shops. 8)

Posted: Fri Apr 25, 2008 1:47 am
by jackssmirkingrevenge
FordGtMan wrote:Oh and by the way JSR, how were you planning on filling your hybrid project with a syringe? did you have a special valve or just open and squirt it in... ?:D
Basically I modfied a schrader cap in such a way that it kept the valve open when it was screwed down, and the syringe nozzle could push-fit into it.

Posted: Fri Apr 25, 2008 1:49 am
by starman
I'm sure you have your reasons for going with a schrader...I would much rather prefer to use a female quick-connect...much more muscular.

Posted: Fri Apr 25, 2008 1:57 am
by Lentamentalisk
Are female quick disconnects rated to 1000+ pressures? Also, is it the male or female side that seals shut, leaving the other one open? (I am pretty sure its the female that seals shut, but not entirely sure)

Posted: Fri Apr 25, 2008 2:39 am
by starman
Lentamentalisk wrote:Are female quick disconnects rated to 1000+ pressures? Also, is it the male or female side that seals shut, leaving the other one open? (I am pretty sure its the female that seals shut, but not entirely sure)
Yes they are rated in the 1000 psi range. The female seals and therefore "acts" most like a schrader. The male is just a blow through so you'll want to incorporate a ball valve behind it. You can build up a male-ballvalve-male unit to connect the female quick connect from the compressor to the gun load female quick connect.

Posted: Fri Apr 25, 2008 7:45 am
by judgment_arms
Hold it, Starman, every last quick-disconnect female I’ve seen for air compressors has a working pressure of only 150psi; unless it’s Chinese, in which case it has no mention of working pressure. :roll:

Now, hydraulic fittings, on the other hand, are rated to a working pressure of 1000psi :) ; and Military quick disconnects are rated to a fail pressure of 3000psi :shock: , unless I’m sorely mistaken.

Posted: Fri Apr 25, 2008 8:03 am
by bluerussetboy
You're right j_a. Most of the time the seal will blow out over 200 psi. It also depends on the locking groove and the ball bearings. Real cheap schraders only only have 3 bearings as opposed to some of the more expensive ones having 5 or 6 to lock the fittings together. 3 bearings is not going to 1000 psi after too many uses.

Posted: Fri Apr 25, 2008 8:07 am
by bigbob12345
judgment_arms wrote:Hold it, Starman, every last quick-disconnect female I’ve seen for air compressors has a working pressure of only 150psi; unless it’s Chinese, in which case it has no mention of working pressure. :roll:

Now, hydraulic fittings, on the other hand, are rated to a working pressure of 1000psi :) ; and Military quick disconnects are rated to a fail pressure of 3000psi :shock: , unless I’m sorely mistaken.
Well Iv taken the quick disconnects on my HP pump up to 350psi without leaking or blowing off although they will be replaced with hydrolic quick connects eventually.