The fact that hydraulic technology has revolutionised engineering applications needs no second opinion. This science has lent an unmatched impetus to dynamics and also made easier the functioning of almost every other utility or activity. For instance, hydraulic power systems are used extensively in aviation, both in the aircraft and allied systems on the ground. The technology has kept pace with the developments witnessed vis-à-vis newer models of aircraft and other gadgets.
A hydraulic power pack is a simple consisting of an electric pump, filters, reservoir, valves, and pressure relief valve. It has several benefits such as doing away with a centralised hydraulic power supply system and long stretches of hydraulic links. Thus there is considerable reduction in weight. A power pack may be driven either by an engine gearbox or an electric motor. The weight is reduced by the integration of essential valves, filters, sensors, and transducers. Thus chances for external leakage are eliminated and thereby simplify troubleshooting as and when the need arises. Some power pack systems are designed and made with an integrated actuator. These systems have applications in controlling the stabilizer trim, flaps, landing gear, brakes and also flight controls with perfection.
In a hydraulic system, the cylinder is one of the most important integrated parts. It is a mechanical actuator that is renders a unidirectional force through a unidirectional stroke. There are variants like special hydraulic cylinders. Depending on the design and applications, these are mainly:
- Telescopic
- Plunger
- Differential
- Position sensing also known as ‘smart’
Hydraulic cylinders have thousands of applications, particularly in earth moving and specialised vehicles like excavators, dumpers and bulldozers used at construction sites and mines, manufacturing machinery, garages, winches in ports and civil engineering. The hammer used in piles foundation is a ready example.