11 precautions for the use of hydraulic pumps

11 precautions for the use of hydraulic pumps

(1) Precautions for hydraulic pump connection

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

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

③The oil suction pipe should be as short as possible, straight, large, and thick. The oil suction pipe generally 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 80-180μm). The drain pipe of the hydraulic pump should be directly connected to the oil tank, and the back pressure of the oil return should not be greater than 0.05 MPa. The oil suction pipe port and the oil return pipe port of the oil pump must be less than 200mm of the lowest oil level of the oil tank. Pay special attention to the installation of oil filters on the oil suction pipe of the plunger pump. The diameter of the stop 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 less than 2500mm.

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

⑤The self-priming height of the hydraulic pump does not exceed 500mm (or the imported vacuum does not exceed 0.03MPa). If a charge pump is used for oil supply, the oil supply pressure must not exceed 0.5MPa. When the oil supply pressure exceeds 0.5MPa, pressure-resistant seals should be used. ring. For plunger pumps, back-filling and self-priming should be used as much as possible.

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

 

 (2) Precautions for the use of hydraulic pumps

①When the hydraulic pump is started, it should be jog several times. After the oil flow direction and sound are normal, run it at low pressure for 5-10 minutes, and then put it into normal operation. Before starting the plunger pump, the pump must be filled with clean working oil through the drain port on the shell.

②The viscosity of the oil changes under the influence of temperature, and the viscosity decreases with the increase of oil temperature. Therefore, the oil temperature is required to be kept below 60℃. In order to make the hydraulic pump work stably at different working temperatures, the selected oil should have The viscosity of the oil is less affected by temperature changes, and the oil temperature characteristics, as well as better chemical stability, anti-foam 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. The hydraulic system without a filter device on the oil suction line must be refueled to the oil tank through an oil filter truck (with a filtration accuracy of less than 25μm).

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

⑤The normal working oil temperature of the hydraulic pump is 15～65℃, and the highest temperature on the pump casing is generally 10～20℃ higher than the oil temperature at the inlet of the pump in the oil tank. When the oil temperature in the oil tank reaches 65℃, the highest temperature on the pump casing The temperature does not exceed 75～85℃.