2 Hydraulic cylinders on a press

[TJ Smith]

When using 2 Hydraulic cylinders on a press, does the pressure double. If 1 puts out 10 tons does 2 then put out 20?

 

Thank You

TJ

[the iron dwarf]

if using the same motor and pump yes you will get twice the force ( but the speed will be half ).

you would also probably have to balance the 2 cylinders, there are valves you can get to do this and i have also seen it done mechanically with a rack and pinion

[Frosty]

AS shorty said, Yes at half speed. And yes, you need to balance them. You can plumb them together with equal length and diameter hard pipe and supply the plumbing at a central point.

 

The base principle of hydraulics is equal pressure on all surfaces IN the system. Where this breaks down is when the fluid is moving. If it takes longer to fill one volume that volume's psi will be lower. Making the supply equal throughout solves this.

 

I tried to avoid hoses when ever I could, too much energy is lost stretching and flexing the hoses. I made them as short as possible and eliminated them when possible. It made for better energy on the work end and smoother operation.

 

I was not making presses though, I was plumbing on drill rigs and carrier drive systems. Different application but same principles and problems.

 

Frosty The Lucky.

[Randy]

I've been running a two cylinder 60 ton press for about 7 years. No equalizer needed. The pressure will equalize between the two cylinders just due to its pressure. It needs equal length hoses, but that's it. You can buy equalizers, but for the little difference that I have between cylinder push I don't need it. If you watch my youtube videos you will not see a difference in the push from either side.

 

The pump and motor were designed for this press and it runs at about 2" per second. A good fast speed for a general forging press.

 

Photo is of the back of my press.