Hydraulic pumps are a major component of hydraulic machinery. Hydraulic pumps refer to pumps that are used primarily to deliver hydraulic liquids such as oil or water to the pump outlet. An interesting feature of hydraulic pumps is that when they are powered by hydraulic liquids, they can also function as motors.
In a fluid-power system the pump is the power source. It is generally operated by an electric motor or an internal combustion engine. The pump uses fluid in a reservoir and then pumps it to an actuator which performs the work of the fluid-power system. The pump works in a rotary fashion. As the pump rotates, it produces a vacuum on the inlet side, which enables the fluid to flow into the pump. The pump then ejects the fluid at a higher pressure than the atmospheric pressure around it. The standard hydraulic fluid that is used in these types of pumps is petroleum oil. However, various types of non-flammable fluids are now being used more often for safety considerations.
Most hydraulic pumps are rated between 500 to 15,000 pound force per square inch (psi), with most continuous-service pumps falling within the 2,000 to 4,000 psi range. Hydraulic piston pumps operate in the higher range for intermittent peak loads. Because hydraulic pumps have such a wide range they are commonly used at home as well as in the industrial sector.
While choosing the appropriate hydraulic pump, some important operational specifications and considerations need to be kept in mind. Hydraulic pumps are mainly differentiated on the basis of the technological differences and the mechanisms that are used to operate them. Some common types of hydraulic pumps are: radial piston, external and internal gear, and vane. A typical hydraulic pump has three to four stages in its operations. Operational specifications such as: the operating temperature, the continuous operating pressure, the maximum operating pressure, the horsepower, the operating speed and the maximum fluid flow must be considered when choosing hydraulic pumps.
Hydraulic pumps are normally made from sturdy materials as they typically experience heavy wear and tear. The air temperature as well as the temperature of the pump will determine the density of the fluid and how well the pump works. Because of this you shouldn’t use the pump in extreme temperatures or let the pump operate to a high temperature.
There are several trusted names in the world of hydraulic pumps. One of the best is Bosch Rexroth. Rexroth pumps are reliable and provide good value for their price.