What is the same between hydraulic and pneumatic?   

jauhar khan
@jauhar123 | Posted 31 Oct. 2019

Both systems, hydraulics and pneumatics, work as an actuator using a pump, and are controlled by valves like a Festo Valve, to convert fluid pressure to mechanical motion. The force that is applied at one point is transmitted to another point via an incompressible fluid. This is usually a type of oil for hydraulics and air for pneumatics.

  • Essentially the two systems are the same. A pneumatic system is anything that uses fluid pressure to do work. A hydraulic pressure system specifically uses water to do work. Every hydraulic system is a pneumatic system, but the sane cannot be said the other way around.
  • Both are similar in that they both use a fluid pressure to do work. However where oils (or water) are nearly incompressible and will transmit forces very similar to what is applied, the compressibility of air means it cannot be used to control fine emovements, e.g. moving a ram a controlled distance and stopping it, while maintaining the position it has stopped in regardless of the variations in load on the ram at the time. Using air, the ram would continue to move independently of the controls.