Relation between Pressure and weight

[Megahertz]

Hi,
1) Not sure if this is the answer you're looking for but 1Bar is roughly equal to 1kg/cm². So if you have a hydraulic cylinder with a diameter of 50mm and a pressure of 75Bar then the "force" is 25*25*PI*75/100=1472kg.

1) What about the length/height of the cylinder? Do I only need to know the radius of the cylinder and apply the above formula?

2) What do I do if I have two cylinders in parallel of the same diameter? Do I multiply the result by 2 ?

[HenrikOlsson]

1) Length doesn't matter, only the surface area upon which the pressure works.
2) Yes, If you double the effective area you double the force. It doesn't matter "how" you double the area.

[Megahertz]

HenrikOlsson, thanks a lot for your help.
Just one last question to confirm my understanding.
So, if I have two different diameters for two cylinders, I should calculate the weight individually for each and add it together towards the end to get the total weight.

[HenrikOlsson]

Yes, or calculate the total area and multiply that by the pressure.
If you have one 100mm and one 50mm cylinder you have an effective area of (50*50*pi/100) + (25*25*pi/100) = 78.5+19.6 = 98.1cm²

Just remember that if the cylinders aren't of the same size (diameter) they won't share the load equally (one will "push" more than the other at any given pressure).

/Henrik.