# Hydraulic Cylinder Compressor?

Ok, so I need to make a compressor that reaches 4500 psi.  I live in a farm town and my dad has a tractor so I wondered if I took two identical hydraulic cylinders and filled one with what I was compressing, and the other I powered with the tractors hydraulic system, if I would be able to achieve high pressure and fill tanks, assuming the hydraulic pump and cylinders are rated for that pressure.  Or could I just use a hydraulic compressor.

3 years ago
No, the capacity is too small. You need a really efficient compressor system. To get to 4500 psi these are usually multicylinder compressors with several stages to get it up to 4500 psi.

3 years ago
I'm wondering whether something could be done with varying-diameter hydraulic cylinders -- apply 100 PSI to a 2"-square piston, get 200 pounds of force, apply that force to a 1"-square piston and get 200 PSI in its hydraulics. Stack those multipliers up until you get enough pressure or something fails...

There's got to be something inherently stupid about this idea, but I'm not sure what.
jj.inc (author)  orksecurity3 years ago
Thanks, I didn't think of this, its a great idea, exept instead of using many pistons I I would still use the one, just multipul time.
3 years ago
Well, that could work if the idea is to put 4500 psi of force on something, but I assumed that since the op mentioned compressor he needed a quantity of air compressed to 4500 psi. Maybe to fill scuba tanks, air packs for the vol. fire department or something like that.
jj.inc (author)  Re-design3 years ago
It is for a large cascade system and/or painball, thanks for your earlier input.
Dark_Snowy2 years ago
You can't just use the one multipul times.

Air volume = origional volume x (origional pressure / final pressure)
Compressed volume of 100 litres = 100 x (1 / 4500)
So 100 litres becomes 0.022 recuring.

If you used a 4500psi pump capable of taking in 100litres an hour it would take 450 hours to fill just a 10 litre tank. 18 days is too long for me.

You need to feed 3000psi into to 4500psi pump.
Compressed volume = 100 x (3000/4500)
So instead you get out 66.66 recuring

So you start with a normal air compressor, say 110psi. Feed that into your 1000psi pump, which feeds into a 2000psi pump which feeds the 3000psi pump which feeds the 4500psi pump.