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Posted: Mon Feb 02, 2009 6:24 pm
by maggotman
Rating not burst pressure i think parts in the pump would fail like last time.

Just got 100 bar with 2 in line then one stalled im up loading a vid of the gage going up just 2 prove it.



Image

I will make another video going from 1200psi and up

Posted: Mon Feb 02, 2009 6:57 pm
by Hotwired
Brian the brain wrote:the best QD couplings I've seen have a rating of " only" 550 psi
Hydraulics also have their QD couplings and they exist for the realms of a few hundred bar.


Play safe Maggotman, I don't want to see you making a headline after a compressor daisy chain blows up in your workshop ^^

Posted: Mon Feb 02, 2009 7:14 pm
by VH_man
they have QD's rated to 3000 for paintball air tanks too. (i have to get one, they have Built in check valves and are TINY

Im amazed at the pressures your acheiving. Be careful though...

Posted: Mon Feb 02, 2009 7:30 pm
by maggotman
I think i have reached the limit with the fridge pump. no matter what i do the last pump always stalls at 130bar.

I think i am going to concet them in parallel and feed them with air just to get more flow so i can get 600~1000psi high volume then i can use higher pressure in my bigger guns i have tested the chamber on my 2 inch piston valve to 700psi i would feel safe using it at 400 and 29 liter at 400psi is gona send items quite far

Posted: Mon Feb 02, 2009 7:36 pm
by Lentamentalisk
The problem here is that so far, Maggot has done absolutely nothing to convince us that he has observed any safety precautions. Once he mentioned wearing safety goggles, but that will hardly save your face when the shell of the compressor comes flying at your heart at close to the speed of sound...
Show us your entire setup, as well as how it has been dug into a 5' deep hole in the ground, and you are hiding inside your house, and maybe we will support your ventures.
Hoping that some part inside the compressor will break before a part on the outside, is like playing Russian roulette with 5/6 of the chambers filled.

Posted: Mon Feb 02, 2009 7:43 pm
by Hotwired
Hope that's the testing over then. I know I'd have turned it off well before 1800psi personally.

Three pumps should be capable of putting out a decent volume at 400psi.

Posted: Mon Feb 02, 2009 8:06 pm
by maggotman
fridge compressors are a a designed pressure vessels. since i am only imputing 60psi ish, i think i am quite safe the only part under 1800psi is some 3mm od copper pipe connecting the pump to the case and some 6mm pipe connecting to to the gage have you ever looked at one in person seen the insides ?

Posted: Mon Feb 02, 2009 8:32 pm
by Lentamentalisk
Correct, they are designed for pressure, but they are not designed for 1800psi, as you demonstrated, by the fact that one of them actually broke, when you tried to get it up that high.
I did a little google searching to try to figure out the operating pressure of a refrigerator, and nowhere did I find a single number over 3.5MPa (507psi)
That means that you should be fine using them in parallel, but in series you are asking to lose your face.

Posted: Mon Feb 02, 2009 8:49 pm
by maggotman
is there something your not getting how is 10cc of 1800psi going to make me lose my face when let into a large volume steel case that is made for pressure. perhaps you could demonstrate on yourself prove me wrong.

Posted: Mon Feb 02, 2009 9:06 pm
by Lentamentalisk
Calm down! I am just trying to keep you safe, and you are asking me to kill my self...
Like I said, the parts inside are not the only parts that can fail. If you want feel that all of the parts, including your connecting fittings and all, are sufficiently pressure rated, show us in some way that that is the case. The reason I am so concerned is that few mortals have access to pipes rated at 1800psi, and getting such a strong connection on a little bit of pipe with a compression fitting or what ever, is quite a feat.

The other issue is that yes, 10cc of 1800psi may not make you lose your face, but 1L of 1000psi gas easily could, if the shell fails.

Posted: Mon Feb 02, 2009 9:19 pm
by maggotman
But the shell is only holding 60psi.

the outlet is braised into a steel female fitting with the gage connected to

Posted: Mon Feb 02, 2009 9:24 pm
by Lentamentalisk
Maybe I missed something, but where is this 60psi number coming from? Are you hooking up a normal compressor to the inlet or what?
Or am I wrong entirely, and the inlet doesn't go into the shell at all?
I worry that, as you say, it was designed for 60psi, but when you run the tanks in series, you are pumping 1000psi into the shell, rather than the usual 60psi that it sees when it is being used in a fridge.

Posted: Tue Feb 03, 2009 1:31 pm
by maggotman
the shell is only under the pressure im in putting to bost psi witch is coming from another compressor but i have a gage between the 2 and i dont go over 60psi or the second pump in the stage stalls.

Posted: Tue Feb 03, 2009 1:48 pm
by jeepkahn
one other note is that a tiny 1500psi leak could quite possibly sever a finger or inject air subcutaneously causing quite an uncomfortable little wound...

Posted: Tue Feb 03, 2009 3:56 pm
by Brian the brain
It was less then 10 cc at 80 bar that broke my face.
Literally broke my upper jaw, chipped a tooth, broke my nose, cut my cheek.Had numerous cuts in my upper lip.

It all healed up pretty nice.The tooth is still chipped, and I have a small scar on my upper lip.


You don't seem to understand what you are doing.

You probably think I'm kidding too
...I find your quest for dangerously high pressures worrying, my friend..