Rational use of hydraulic oil pump in hydraulic system

In the hydraulic system, the hydraulic oil pump is the most important power output component and is indispensable. However, in the hydraulic system, there are many key points in the use of the oil pump, which need to be known, otherwise, the service life of the oil pump may be reduced or damaged. Let's take a look at Yihe hydraulic manufacturers.

①The hydraulic oil pump can be installed with a support or a flange. The pump and the prime mover should use a common foundation support, and both the flange and the foundation should have sufficient rigidity. Special attention: The piston pump with a flow rate greater than (or equal to) 160L/min should not be installed on the oil tank.

②The hydraulic oil pump and the output shaft of the prime mover should be connected by an elastic coupling. It is strictly forbidden to install a pulley or gear on the hydraulic pump shaft to drive the hydraulic pump. The seat is used to install the pulley or gear, and the coaxiality error between the support and the pump shaft should not be greater than Φ0.05mm.

③ The oil suction pipe should be as short, straight, large and thick as possible. Generally, the oil suction pipe needs to be equipped with a coarse filter with a nominal flow rate not less than twice the pump flow rate (the filtration accuracy is generally 80-180 μm). The oil drain pipe of the hydraulic pump should be directly connected to the oil tank, and the oil return back pressure should not be greater than 0.05MPa. The oil suction pipe port and the oil return pipe port of the oil pump must be 200mm below the minimum oil level of the fuel tank. Special attention should be paid to the installation of oil filter on the oil suction pipe of the piston pump. The diameter of the shut-off valve on the oil suction pipe should be one block larger than the diameter of the oil suction pipe. The length of the oil suction pipe is L<2500mm, and there are no more than two pipe elbows.

④The oil inlet and outlet of the hydraulic oil pump should be installed firmly, and the sealing device should be reliable, otherwise air inhalation or oil leakage will occur, which will affect the performance of the hydraulic pump.

⑤The self-priming height of the hydraulic oil pump shall not exceed 500mm (or the inlet vacuum shall not exceed 0.03MPa). If the oil supply pump is used for oil supply, the oil supply pressure shall not exceed 0.5MPa. When the oil supply pressure exceeds 0.5MPa, the pressure-resistant seal shall be used lock up. For plunger pumps, reverse irrigation and self-priming should be used as much as possible.

⑥Before installing the hydraulic oil pump, check whether the depth of the installation hole is greater than the shaft extension of the pump to prevent the phenomenon of shaft jacking, otherwise the pump will be burned.

Precautions for the use of hydraulic oil pumps:

① When the hydraulic oil pump is started, it should be jogged several times. After the oil flow direction and sound are normal, it should be operated under low pressure for 5 to 10 minutes, and then put into normal operation. Before the plunger pump is started, the pump must be filled with clean working oil through the oil drain port on the casing.

②The viscosity of the oil is affected by the temperature, and the viscosity of the oil decreases with the increase of the temperature, so the oil temperature is required to be kept below 60°C. In order to make the hydraulic pump work stably at different working temperatures, the selected oil should have The viscosity is less affected by temperature changes, oil temperature characteristics, and better chemical stability, anti-foaming performance, etc. It is recommended to use L-HM32 or L-HM46 (GB11118.1-94) anti-wear hydraulic oil.

③The oil must be clean and must not be mixed with mechanical impurities and corrosive substances. For hydraulic systems without filter devices on the oil suction pipeline, oil must be refueled to the oil tank through an oil filter vehicle (filter accuracy less than 25 μm).

④The maximum pressure and maximum speed of the hydraulic oil pump refer to the peak value allowed in a short period of time during use, and long-term use should be avoided, otherwise the life of the hydraulic pump will be affected.

⑤The normal working oil temperature of the hydraulic oil pump is 15-65°C. The highest temperature on the pump casing is generally 10-20°C higher than the oil temperature at the pump inlet in the fuel tank. When the oil temperature in the fuel tank reaches 65°C, the highest temperature on the pump casing The temperature should not exceed 75-85°C.