What is Pressure?

Oil is an incompressible liquid. It exerts the same pressure in all directions, as long as the pump can provide pressure.

And don't forget enough volume to keep the system charged.

Isn't the area. All of the pipe big or small with in the system. Their connect together.

All areas of a closed hydraulic system will be at the same pressure.

(the hydraulic system works due to those big'uns and little'uns)

You just have to use the Google square to round calculator.

Search engines seem to be a foreign concept here.

Maybe Common Core math would work.

:-)

Lyn, its obviously a pair of square pistons.

A piston with a larger area would have a greater force. Suppose you have a hydraulic system with a large piston (say 10 square inches area) and a small piston (1 square inch area). If you move the small piston 1 inch, it displaces 1 cubic inch of fluid, and the large piston moves 1/10 inch due to the 1 cubic inch of fluid. It works like a lever, where the part that moves the least has the greater force. It's all because of conservation of energy. Energy equals force times distance.

I would not go into the concept of energy conservation when discussing pressure and force. But thats just me trying to understand OP and its misunderstanding and where it comes from.

You are witnessing the system pressure constant (say 290 bar) when the system is static, so the pressure is the same throughout. When the fluid moves within the system, say when a plunger (of a cylinder) is pushed out or in, the instantaneous pressure inside the cylinder should be more or less than the supply/drain line. Unless there is pressure difference the fluid will not go from one place to other.

That's right but you're going beyond what OP was asking and likely to confuse him more. #4 pretty much covered it IMHO.

To point out by your logic it's the gauge your testing with. It has a port in it that the area of never changes. The port is another branch off of any size line you attach it to.

I like your way of thinking!