Hydraulic Pump Connection and Use Precautions

Ⅰ. The hydraulic pump connection precautions

1. The hydraulic pump can be installed with bearings or flanges. The pump and the prime mover should use a shared base bearing, and the flange and foundation should have sufficient rigidity. Special attention: Piston pumps with a flow rate greater than (or equal to) 160L/min should not be installed on the oil tank.

2. An elastic coupling should be used to connect the hydraulic pump and the output shaft of the prime mover. It is strictly forbidden to install a pulley or a gear-driven hydraulic pump on the hydraulic pump shaft. If a pulley or a gear must be used to connect the pump, a pair of support seats should be installed When the pulley or gear is used, the coaxiality error between the bearing and the pump shaft should not be greater than Φ0.05mm.

3. The suction pipe should be as short as possible. Straight, large and coarse, the oil suction pipeline generally needs to be equipped with a coarse filter whose nominal flow is not less than twice the pump flow (the filtration accuracy is generally 80 to 180 μm). The oil 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 0.05MPa. The oil pump suction pipe port and the oil return pipe port are required to be 200mm below the minimum oil level of the oil tank.

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

5. The self-priming height of the hydraulic pump should not exceed 500mm (or the inlet vacuum should not exceed 0.03MPa). If the oil of the charge pump is used, the oil pressure should not exceed 0.5MPa. When the oil pressure exceeds 0.5MPa, a pressure sealing ring should be used. For plunger pumps, self-priming should be used as much as possible.

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

Ⅱ. Precautions for the use of hydraulic pumps

1. Start the hydraulic pump and move it several times first, the oil flow direction and sound are normal, run at low pressure for 5 to 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 oil discharge port on the pump casing.

2. The viscosity of the oil is affected by the temperature change. The oil temperature increases and the viscosity decreases, 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 a viscosity that is affected by the oil temperature change. Smaller characteristics, as well as better chemical stability and anti-foaming properties.

3. The oil must be clean, and must not be mixed with mechanical impurities and corrosive substances. The oil suction line has no filter device hydraulic system, and must be filtered by an oil truck (filtering accuracy less than 25μm) to the fuel tank.

4. The maximum pressure and maximum speed of the hydraulic pump refer to the allowable peak use in a short period of time. Long-term use should be avoided, otherwise the service life of the pump will be affected.

5. The normal working temperature of the hydraulic pump is 15°C to 65°C, and the maximum temperature on the pump casing is 10°C to 20°C higher than the oil temperature at the pump inlet. When the oil temperature reaches 65°C, the maximum temperature does not exceed 75°C to 85°C.