Vogele Basic Training Hydraulics & Electrics

H.13.0 Annex
H.13.4 Disadvantages
- The elasticity of the fluid that leads to compression under pressure is a disadvantage of hydraulic drives.
Under certain circumstances, this can lead to pressure or motion oscillations. However, this problem only affects
drives with stringent requirements on the uniformity of the speed under greatly varying loads, e.g. feed drives
on machine tools. This effect has to be counterbalanced via a flexible coupling, which increases the costs.
- Stringent demands on filtering the hydraulic fluid.
- Development of heat and a consequent change in the viscosity of the hydraulic fluid.
- Valve switching noise.
- Danger of leakage.
- Low clearance between hydraulic components.
- Temperature dependency of hydraulic oils (viscosity and expenditure of energy increase with decreasing temperatures).
- Leakage oil loss.
- Components are heavier than pneumatic components.
- High degree of flow loss within the hydraulic fluids, which is converted into heat and can elevate the system temperature
(energy loss).
- Tendency to oscillate as a result of pressure surges and the associated noise generation.