Hydraulic pump , which is a water pump that uses the kinetic energy of flowing water to force a small fraction of that water to a reservoir at a higher level, is a mechanical device used to move liquids in a hydraulic system.
It can be mainly divided into hydrostatic and hydrodynamic. The former is a kind positive displacement pumps . Being distinguished from hydrostatic pump , the later one can be fixed displacement, in which the displacement cannot be adjusted. At the same time, hydrodynamic pumps have a more complicated construction that allows the displacement to be adjusted in special need by the user.
How does the hydraulic pump work? It works based on Pascal’s Law which states “The pressure, in a static hydraulic fluid in a closed system is everywhere the same”. Generally, in a hydraulic pump , water or another fluid is highly pressurized and moved through various motors and cylinders. To control the fluid various valves, hoses and tubes block or disperse the fluid creating the pressure and force without the need of an external power source. By using the kinetic energy (molecular energy) of the water/fluid to power the pump , no electricity is needed. And according to the law, if you increase the pressure in one area of a system, it increases throughout the system.
Of course, like many other types of pumps , the hydraulic pump also has a wide range of applications. Its application can be summarized as transferring and circulation of liquids within light industry and farming irrigation and pressure boosting. And it also can be applied tin cooling systems and air-conditioning systems.
And in daily applications, especially in the hydraulic installation, one pump can serve more cylinders and motors. However, the attendant problem is that in that case a constant pressure system is required and the system always needs the full power. The more economic way to solve this problem is to give each cylinder and motor its own pump .
The hydraulic pumps include gear pump , screw pump , bent axis pump , peristaltic pump , and so on. All these different types of pumps have many common features. Most of them are designed to be ideal for water supply, irrigation, commercial and industrial uses. Besides, most of them are made of cast iron and brass. Taking the gear pump as an example, it is the most common where pressure can remain low in simple systems. They are simple, reliable, and much less dirt sensitive.