How Do Hydraulic Cylinder Work

Update:Sep 12, 2019

Hydraulic system generally speaking its convert from Me […]

Hydraulic system generally speaking its convert from Mechincal energy to hydraulic energy such as centerfugle pump which can transfer the flow through the pipe.

The machines called ‘hydraulic machines’ or ‘hydraulically powered’ or any synonyms of that are using fluid power. It means that the power is transfered through oil (in pneumatics the air is the fluid).

To make hydraulic machine work, you first need some source of the energy which is either electric or ICE. Then there has to be at least one pump connected to this source.

PUMP is a device which converts the energy from rotating shaft (the power is then described by rpm and torque) into the hydraulic power which is flow and pressure. Pump is characterized by its displacement which describes how much fluid it will pump while rotated by one turn.

Hydraulic actuators are either linear - rams/cylinders or rotational - motors.
In linear actuators, hydraulic power is converted into mechanical displacement. Flow provides the speed and pressure provides the force (this is actually other way around but I will explain it later).

Important thing in hydraulics which many people don’t understand is that pump does not generate the pressure. Pump generates the flow and the pressure comes from the load in the system (force on ram or torque on motor). Of course, pump together with the energy source have to be able to work under certain pressure. To make it clearer consider simple example when you have massive motor, lets say 300kW together with massive pump, so you could expect crazy high flow and pressure, but if you will power up some actuator with really low load, the real pressure in the circuit will be really low, because the load generate the pressure in circuit, not the pump.