Hydrolic bottle jack pump

Sticky_Tape · Thu Jan 29, 2009 1:35 pm

I had an idea for a really really high pressure pump made out of a bottle jack. I bought a bottle jack from canadien tire to have a look at it (it was on sale for $10). The pump has a small diameter and a lever like those old water pumps. You may say it is made for oil and scince that is incompressable check valve placement would be an issue. Well it would be because on the diagram I found on google images shows that the check would be at the base of the hydro cylinder a bit away from the pump creating dead space if it was use pneumaticly. Maybe you would be able to cut the pump off and use your own check valve I don't know. It would also olny be able to fill little chambers to high pressure but even that would be powerful. Just throwing my thoughts around. EDIT: I think that there is a check valve right at the base of the pump shaft that I didn't notice before I guess you could put the output on that tube.

maggotman · Thu Jan 29, 2009 2:59 pm

it was not made for air i would suspec the seals would fail quite fast use it to sompress a big spring an make a huge air rifel lol

Sticky_Tape · Thu Jan 29, 2009 3:17 pm

The hydro would be under alot more pressure with 2 tons on it I think. I know all the pump diameter psi thing incompressable bla bla.

psycix · Thu Jan 29, 2009 7:50 pm

The terribly short stroke may be annoying.

Sticky_Tape · Thu Jan 29, 2009 8:51 pm

Yeah I thought that but it would be high pressure like really high pressure 1000 or so psi so the size of the chamber wouldn't need to be large you could make a damn powerful mini.

VH_man · Thu Jan 29, 2009 9:45 pm

Technically, You could mount this all to a 2HP fan motor and a Cam, And have the motor do all the pumping for you....... Just a thought.

Im doing this with my next Shock Pump Venture. It just makes more sense!!!!!

maggotman · Fri Jan 30, 2009 1:50 pm

that pump wont make hpa even if you made your owen valves you could not get rid of the dead space and it would be stupidly slow

Sticky_Tape · Fri Jan 30, 2009 3:20 pm

like I said tiny chamber it olny needs to be tiny. So why wouldn't it make hpa? I am getting the idea that it has such a small diameter pump for HIGH PRESSURE. The hydrolic jack that I bought has a ram about 3/4'' in diameter and it can lift 2 tons. 0.375 X 0.375 X 3.14 x 2000 pounds = 883.5 psi don't you think that is relatively high pressure? I don't even know how much 2 tons is in pounds I just say 2000 but I think 2400.
0.375 X 0.375 X 3.14 X 2400 pounds = 1060.2 psi. The dead space wouldn't be too hard to shrink.

psycix · Fri Jan 30, 2009 4:17 pm

But on 200 bar the dead space may not be any more then 1/200th of the total volume.
A longer stroke would help and you could also look into a multi-stage pump.
If you feed the thing with a 8-9 bar from a shop compressor the dead volume becomes 10 times as ineffective. There are some ram dangers when feeding pumps with pressure though.

Sticky_Tape · Fri Jan 30, 2009 6:56 pm

I don't think it would be very dangerous with the pump lever and the small diameter and the short sroke. I think I might do this with my hydrolic jack could get interesting results. Any ideas about how I should go about this?
EDIT: I have an idea

maggotman · Fri Jan 30, 2009 7:13 pm

i think your problem will be the dead space as mentiond above and i think your seals wont seal properly because sealing a liquids is easy than air and it wont be lubricated try it you never no

Sticky_Tape · Fri Jan 30, 2009 7:45 pm

It would be easy to add lube through the input.

psycix · Mon Feb 02, 2009 10:11 am

Then there is only one way to find out! Go ahead and do your thing.
If you can take it apart and look down onto the dead volume you could try to fix that up with a bit of epoxy.

john bunsenburner · Mon Feb 02, 2009 10:17 am

I am not sure but i would be careful with hpa and epoxy, expecially pluggig holes with it, i am afraid it could either shatter or be puhed out(seeing as how all he tubes will be lubricated), so clean very well before using the epoxy i guess, i am not sure at all if the epoxy can handle such pressures though...

kenbo0422 · Tue Oct 20, 2009 11:37 am

The handle on a pump like that gives you an advantage, like a lever. Say for instance 10 to 1. If you put 10 lbf on the handle, it pushes the piston down with 100 lbf. Say the piston is 1/4" total area. That will give you 400 lbs/in^2 in the hydraulic fluid, max. It pumps into a larger cylinder. Lets say that cylinder has a piston with a face of exactly 2 square inches. This means that you can lift, or push a load of 400 lbs/in^2 x 2 in^2, or 800 lbs.

The pressure you are going to want will have to be generated on the outside of the jack. Using the jack to push against another piston and cylinder setup with a check valve into a small tank. The jack and cylinder will have to be placed in a strong frame to allow the pressures to work. What you're looking at is a hydraulic press, like for use in pressing bearings. You would probably have to unload the jack and start over to finish pressurizing your tank, depending on the size of the tank/charging cylinder, maybe several (hundred) times. A 4" steel pipe with a piston, check valves and return spring would eliminate a lot of repetitive unloading of the charging chamber.

To get 500psi into 1 cubic inch you would have to compress 34 cubic inches of air. A pump up gun with a small cylinder, a large stroke, and a large lever would be easier to use, even though it may take 34 strokes with a total volume of 1 inch in the cylinder. But, the hydraulic pump would take at least that many strokes to do it as well.

Yes, its an old thread...

Hydrolic bottle jack pump

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