The fail pressure of a Schrader valve?

[Gippeto]

@ rp181

Some information on dead weight testers.

http://www.chandlerengineering.com/prod ... ration.cfm

This is similar (but not the same) to the tester I used.

http://dh-budenberginc.com/common/showi ... =210&h=210

[fogus]

Just to clarify, has anyone tested a schrader until it failed? If so, what pressure did it fail at?

[Gippeto]

300bar (4350psi) not enough for you?

What ARE you building?

I'll throw it back on the tester and take it to 700bar (~10000psi) or burst. (That's my comfort level.)

I'll post the results here later.

Edit: It is now "later".

I tested the same schrader to 700bar.

It did not "blow up" or even leak while under pressure.

Post test examination revealed the sealing face of the valve core to be destroyed. (Hey, 700 bar is REAL pressure, something had to happen.)

This was the only visible damage.

A new core, and this one will be back in business. 8)

I guess no one has tested a schrader to burst yet.

I think I can live with that.

[jackssmirkingrevenge]

Edit: It is now "later".

And good stuff, though given the fact that the schrader stem is held shut by pressure, somewhat expected.

[fogus]

300bar (4350psi) not enough for you?

What ARE you building?

I'll throw it back on the tester and take it to 700bar (~10000psi) or burst. (That's my comfort level.)

I'll post the results here later.

Edit: It is now "later".

I tested the same schrader to 700bar.

It did not "blow up" or even leak while under pressure.

Post test examination revealed the sealing face of the valve core to be destroyed. (Hey, 700 bar is REAL pressure, something had to happen.)

This was the only visible damage.

A new core, and this one will be back in business. 8)

I guess no one has tested a schrader to burst yet.

I think I can live with that.

Oh dear, no, I misunderstood. I thought the maximum anyone tested it was to 700psi.

I thought that you were only testing black iron joints, not schrader.

Thanks though, I really appreciate it! Interesting results. Sorry about your valve

I plan to stay below 1000psi.

Gippeto, have you ever tested any PVC sch40 or 80? I'd be interested to know what they normally blow at. I am most interested in 1.5 and 2 inch pieces with glued end caps.

Thanks man!!

[Gippeto]

I don't know Jack, I was half expecting the threads on the core to shear off, sending the core out like a bullet. It's happened before with a quick connect.(Yeah, not threaded, I know.)

The "steel guts" penetrated a piece of fir about 1/4", that would have hurt some.

@ fogus

No, I have not tested any pvc. Pressure rated pvc generally has a rating printed on it.

General consensus seems to be that the fittings have a rating matching that of the pipe they fit.

Use the lowest rated part as the maximum.

I use less than the rating on pvc. (I guess I'm a coward. )

It's all about comfort level.

[kablooie]

Very cool info, thank you for testing this stuff.

When I saw this topic title, I immediately though of rubber tire valves, which, before I got some threaded schraders, I was using on my high pressure cannon . If anyone is interested, my rubber valve blew out at 200 psi, scaring the pants off me. Luckily it all stayed (just barely) in one piece.

I agree with staying below the rating of pvc, I've grown attached to my shrapnel-free body parts.

[john bunsenburner]

I know old topics shouldn't be thrown up without reason but I believe i have on todo so:

Gippeto you mentioned that you tested a quick disconnect until it burst, mind telling us what it was rated to and when it burst, I would like to know as i am planning on using a few quick disconnects on my gun. I would of sent a pm but i think every one can profit from info like that.

[Gippeto]

It's really not relevant John.

The quick connect was rated for 15000psi, it's unlikely to be the same as what most people are using.

It failed at 15000psi. Stored energy in the bourdon tube of the gauge is what made it somewhat "dramatic". It would have been much worse with air in the system.

It had been in use for many years before failing. Fatigue likely played a role in its failure.

Hydraulic supply stores are likely your best bet for quick connects with a higher pressure capability.

[john bunsenburner]

what about price, are such quick connects horribly expensive? If they are over 5$ a piece, what would a better alternative for a way to connect a HP hose to my a tank, threaded ends, small sized is really the best?

[Gippeto]

Horribly...no...but more than $5.

Threaded connections using suitable materials, are incredibly strong, and very easy to use.

For example;

My hp nitrogen regulator has a brass body, with 1/4"npt connections, and is rated for 6000psi inlet. In stainless, the rating goes up to 10000psi.

At the 800psi that I think you were looking at using, I would simply look at paintball equipment. You would be well inside the working rating of such fittings.

[john bunsenburner]

And price wise?

[Gippeto]

I'm not sure what you mean?

Each half of a quick connect has threads for mounting, so you'll need threaded ends on your hose, etc. anyway. So if you just used threaded fittings and left out the quick connects, it would have to be less money, right?

The paintball fittings will also require you to have existing threads to mount them.

You've made mention on several occasions that things cost "more" in Switzerland. It might be best for you (and more accurate) if you were to price these things locally.

Hydraulic fittings from the nearest tractor dealers should be your first phone call.