The hydraulic pump is the power component of the hydraulic system. It is driven by an engine or an electric motor, sucks oil from the hydraulic oil tank, forms the pressure oil and discharges it, and sends it to the actuator. Hydraulic pumps are divided into gear pumps, plunger pumps, vane pumps and screw pumps according to their structure.

1. Working principle of hydraulic pump
The working principle of the hydraulic pump is that the movement brings about a change in the volume of the pump cavity, thereby compressing the fluid so that the fluid has pressure energy. The necessary condition is that there is a change in the sealing volume of the pump cavity.

A hydraulic pump is a hydraulic component that provides pressurized liquid for hydraulic transmission, and is a type of pump. Its function is to convert the mechanical energy of power machines (such as electric motors and internal combustion engines) into liquid pressure energy. Its cam is rotated by an electric motor. When the cam pushes the plunger to move upward, the sealing volume formed by the plunger and the cylinder is reduced, and the oil is squeezed out from the sealing volume and discharged to the required place through the one-way valve. When the cam rotates to the descending part of the curve, the spring forces the plunger downward to form a certain degree of vacuum, and the oil in the tank enters the sealing volume under the action of atmospheric pressure. The cam makes the plunger rise and fall continuously, the sealing volume decreases and increases periodically, and the pump continuously absorbs and discharges oil.

There are many factors affecting the service life of the hydraulic pump, in addition to the design and manufacturing factors of the pump itself, the selection of some components related to the use of the pump (such as couplings, oil filters, etc.), and the operation during the commissioning process are also related.

2.the composition of the hydraulic pump
The hydraulic pump consists of three parts: coupling, hydraulic oil tank and oil filter.

1. Coupling:
The hydraulic pump drive shaft cannot bear radial force and axial force, so it is not allowed to directly install pulleys, gears and sprockets on the shaft end, and couplings are usually used to connect the drive shaft and the pump drive shaft. If due to manufacturing reasons, the coaxiality between the pump and the coupling exceeds the standard, and there is a deviation during assembly, the centrifugal force will increase with the increase of the pump speed, and the coupling will be deformed, and the large deformation will increase the centrifugal force. A vicious circle is created, which results in vibration and noise, which affects the service life of the pump. In addition, there are other influencing factors such as the loose coupling pin and not being fastened in time, and the wear and tear of the rubber ring not being replaced in time.

2. Hydraulic oil tank:
The main function of the hydraulic oil tank in the hydraulic system is to store oil, dissipate heat, separate the air contained in the oil and eliminate foam. When selecting a fuel tank, first consider its capacity. Generally, mobile equipment takes 2 to 3 times the maximum flow rate of the pump, and fixed equipment takes 3 to 4 times. Secondly, consider the oil level of the oil tank. When all the hydraulic cylinders of the system are extended, the oil level of the oil tank should not be low. At the lowest oil level, the oil level should not be higher than the highest oil level when the oil cylinder is retracted; finally, considering the structure of the oil tank, the diaphragm in the traditional oil tank cannot play the role of depositing dirt, and a vertical diaphragm should be installed along the longitudinal axis of the oil tank. There is a space between one end of the diaphragm and the end plate of the fuel tank so that the space on both sides of the diaphragm is connected. The oil inlet and outlet of the hydraulic pump are arranged on both sides of the diaphragm at the disconnected end, so that the distance between the oil inlet and the oil return is the farthest. The hydraulic oil tank has more cooling effect.

3. Oil filter:
Generally, pollutants with a particle size of less than 10 μm have little effect on the pump, while those larger than 10 μm, especially above 40 μm, have a significant impact on the service life of the pump. The solid pollution particles in the hydraulic oil can easily aggravate the surface wear of the relatively moving parts in the pump. Therefore, it is necessary to install an oil filter to reduce the pollution degree of the oil. Filtration accuracy requirements: 10-15μm for axial piston pumps, 25μm for vane pumps, and 40μm for gear pumps. The pollution and wear of the pump can be controlled within the allowable range. At present, high-precision oil filters are widely used, which can greatly extend the service life of hydraulic pumps.

3. Classification of hydraulic pumps

Common types of hydraulic pumps:

1.According to whether the flow can be adjusted, it can be divided into: variable pump and quantitative pump. The output flow can be adjusted according to the needs called variable pump, the flow can not be adjusted called quantitative pump.

2. According to the pump structure commonly used in hydraulic system, it is divided into three types: gear pump, vane pump and plunger pump.
Gear pump: small in volume, simple in structure, less strict on oil cleanliness, and cheaper in price; but the pump shaft is subject to unbalanced force, serious wear, and large leakage.

Vane pump: divided into double-acting vane pump and single-acting vane pump. This kind of pump has uniform flow, stable operation, low noise, higher working pressure and volumetric efficiency than gear pump, and more complicated structure than gear pump.
Plunger pump: high volumetric efficiency, small leakage, can work under high pressure, mostly used in high-power hydraulic systems; but complex structure, high requirements for materials and processing accuracy, high price, and high requirements for oil cleanliness.
Piston pumps are generally used when gear pumps and vane pumps cannot meet the requirements. There are some other forms of hydraulic pumps, such as screw pumps, etc., but the application is not as common as the above three.

If you want to purchase the hydraulic pump,Beijing Vigers Co., Ltd. is a good choice.

Beijing Vigers Co., Ltd. Beijing Vigers Co., Ltd. is located in Beijing, the capital city of China, which is a manufacturer specializing in machinery parts. The mian products are Fuel Injector, turbocharger, Hydraulic Pump, Cylinder HeadInjector Nozzles, Valve Assembly, Fuel Injection Pump, Machinery Parts and so on.

And Vigers’s products are exported to the United States, the United Kingdom, Finland, Germany, South Korea, Vietnam, India and other countries, and have won the recognition of foreign consumers with high quality and low price, and have a good reputation in foreign markets.

For more information, please contact:
Kaiyuan Business Office, Haidian District, Beijing, China
Telephone (+86) 15911077288. Email: [email protected].
Website: https://www.bjvigersinjector.com/en-US/