Page 1 of 1

hydraulic fittings

Posted: Wed Jun 20, 2007 3:49 am
by RDX,
have anybody used hydraulic pipe and fittings to make cannon for high pressures . they cost much but I live in Finland and I cant find high pressure fittings for compressed air . hydraulic pressure raiting for those fittings and pipe is over 600bar so do you think that its ok to use them for hybrid or high pressure cannon :D

Posted: Wed Jun 20, 2007 3:53 am
by Hotwired
Yes but you're going to have to fork out waaay too much.

They're made to much tighter tolerances than pneumatic fittings and I've heard they have to be because o-rings deform at hydraulic pressure so they can't be used.

Getting pneumatic fittings mailed in from another country would probably be cheaper...

Posted: Wed Jun 20, 2007 8:50 am
by mark.f
Not to mention most hydraulic fittings I've seen over in the state are pretty small. You can get bigger ones but they go up in price a lot.

Only hydraulic fittings I've seen that look useful in pneumatic applications would be the double shut-off quick-disconnect couplings. That way, when you disconnect a 50' air hose, it doesn't shoot around smacking things if you don't hold it, like mine does. :P

Posted: Wed Jun 20, 2007 9:23 am
by spudthug
Only hydraulic fittings I've seen that look useful in pneumatic applications would be the double shut-off quick-disconnect couplings. That way, when you disconnect a 50' air hose, it doesn't shoot around smacking things if you don't hold it, like mine does.
i have a pair of those (mine are 3/8) and i am trying to find a use for them...any ideas?

as for teh hydraulic fittings..why not order from a online site? so ur saying u have no hardware stores within 20 miles of your house? i would cry...lol...

Posted: Mon Jul 02, 2007 8:46 am
by Jolly Roger
Yeah I'm trying to find something along those lines. Does anyone know what hydrualic rams etc. use instead of o-rings?

Posted: Mon Jul 02, 2007 11:01 am
by Hotwired
Actually they do use o-rings :oops:

I'ts just that more commonly you'll find they use more complicated non-o-ring seals like these instead.

Posted: Mon Jul 02, 2007 11:11 am
by Jolly Roger
Yeah thats what I was reffering to. Cheers. I think I might just stick with the o-rings though, they seem a little too complex. I don't think the o-rings will fail on me if I use them properly. :wink:

Posted: Mon Jul 02, 2007 1:56 pm
by frankrede
woot woot nptf threads!
I called a local hydraulic fittings supply and the prices were outrageous they wanted $70 for a 1/4" check valve. Rated to some ungodly high pressure though

Posted: Mon Jul 02, 2007 4:40 pm
by Hotwired
Heh

It's like using inch thick steel for your hairspray combustion :P

Posted: Tue Jul 03, 2007 12:54 am
by frankrede
Hotwired wrote:Heh

It's like using inch thick steel for your hairspray combustion :P
Haha, I have seen it before!
But with 1/2" aluminum and propane:(

Posted: Tue Jul 03, 2007 1:13 am
by TwitchTheAussie
Jolly Roger wrote:Yeah I'm trying to find something along those lines. Does anyone know what hydrualic rams etc. use instead of o-rings?
Where are you from mate? .

Posted: Tue Jul 03, 2007 2:37 am
by Jolly Roger
I'm from qld, aus, but I think I might just stick with the o-rings for now anyway.

Posted: Thu Jul 05, 2007 1:51 pm
by WOW!!
www.surpluscenter.com has a bunch of stuff and I think they ship over seas.