- Fluid Power efficiently transfers energy into motion
- Hydraulic oil is essentially incompressible; whereas air is highly compressible
- Fluid Power allows precise and smooth control of energy transfer
- Force = Cylinder Area x Pressure
Example:
A cylinder with 63 mm bore and 32 mm rod with 50 bar (5 MPa) on full bore side can generate a force of 1500 kgf. This is enough to lift a small family car.
Hydraulic fluids (liquids) are essentially incompressible and are generally used at higher pressures. Gases, e.g. air, are highly compressible. To achieve a 50 bar pressure with a gas the volume needs to be reduced to 1/50 of the ambient volume. This takes far more energy than generating the same pressure in a hydraulic fluid. The maximum pressure for pneumatic systems is typically 7 bar (0.7 MPa). Hydraulic systems are much safer and more controllable than pneumatic systems.
A cylinder with 2.5 in bore and 1.25 in rod with 700 psi on full bore side can generate a force of 3400 lbf. This is enough to lift a small family car.
Hydraulic fluids (liquids) are essentially incompressible and are generally used at higher pressures. Gases, e.g. air, are highly compressible. To achieve a 700 psi pressure with a gas the volume needs to be reduced to approximately 1/50 of the ambient volume. This takes far more energy than generating the same pressure in a hydraulic fluid. The maximum pressure for pneumatic systems is typically 100 psi. Hydraulic systems are much safer and more controllable than pneumatic systems.
