Hydraulics is the use of liquids as a source of mechanical force. Hydraulic machinery uses pressurized liquid as the powering medium. Hydraulics are used in a wide range of different industries including construction, automobile engineering, and aviation engineering.
Hydraulics is the use of liquids to carry out mechanical work. Hydraulics is the liquid counterpart to pneumatics, which uses gases. Hydraulics use the movement of pressurized fluids through pipes as a source of mechanical force.
Blaise Pascal first laid out the principles behind hydraulic power in 1648. He found that when pressure is applied to a fluid in a closed system, the pressure is transmitted in all directions through the liquid. One early device that used hydraulic power is the hydraulic press, also known and the Bramah Press. The press was invented by British inventor Joseph Bramah in 1795. The press is used in a wide range of metal forming functions.
Bramah was a big proponent of hydraulic power and recommended that hydraulic power grid systems were built. These hydraulic power grid systems are similar to modern electrical power grid systems. Hydraulic accumulator towers were built in certain areas to provide water pressure to power machinery. In Grimsby, England, a 94 meter high tower was built to contain 140,000 liters of water. The hydraulic power was used to operate machines as well as the port's locks.
Hydraulic power is now used for a wide range of applications. Car brakes use hydraulic power to apply a force to the wheel. The break pedal is connected to a piston so that when it is pushed, it puts the brake fluid under pressure. This pressure then causes brake pads to touch the brake disc, which causes friction that slows the car down. Hydraulics are also used in construction vehicles, like backhoes. A backhoe has three joints, similar to a human arm. Instead of muscles, the backhoe uses pistons connected to pumps which can cause then to extend or contract using hydraulic pressure. These pumps are controlled by the operator from the cab.