Use and maintenance of plate bending machine hydraulic pump (2)
① Precautions for connecting the hydraulic pump of the plate bending machine
a. The hydraulic pump of the plate bending machine can be installed with a support or flange. The pump and the prime mover should use a common basic support, and both the flange and the foundation should have sufficient rigidity. Pay special attention to the fact that piston pumps with a flow rate greater than (or equal to) 160L/min should not be installed on the oil tank.
b. The hydraulic pump of the plate bending machine and the output shaft of the prime mover should be connected by an elastic coupling. It is strictly prohibited to install a pulley or gear on the hydraulic pump shaft of the plate bending machine to drive the hydraulic pump of the plate bending machine. If the pulley or gear must be connected to To connect the pump, a pair of supports should be added to install the pulley or gear. The coaxiality error between the supports and the pump shaft should not be greater than 0.05mm.
c. The oil suction pipe should be as short, straight, large and thick as possible. 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 80~180/m). The drain pipe of the hydraulic pump of the plate bending machine 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 and oil return pipe mouth of the oil pump must be 200ram below the lowest oil level of the oil tank. Pay special attention to the fact that oil filters are not allowed to be installed on the oil suction pipeline of the plunger pump. The diameter of the stop valve on the oil suction pipeline should be one step larger than the diameter of the oil suction pipeline. The length L of the oil suction pipeline should be less than 2500mm, and there should be no more than 2 pipeline elbows.
d. The inlet and outlet of the hydraulic pump of the plate bending machine should be firmly installed, and the sealing device should be reliable. Otherwise, air inhalation or oil leakage will occur, which will affect the performance of the hydraulic pump of the plate bending machine.
e. The self-priming height of the hydraulic pump of the plate rolling machine shall not exceed 500mm (or the inlet vacuum degree shall not exceed 0.03MPa). If an oil supply pump is used to supply oil, the oil supply pressure shall not exceed 0.5MPa. When the oil supply pressure exceeds 0.5MPa, a pressure-resistant sealing ring must be used instead. For plunger pumps, try to use reverse pouring and self-priming.
f. Before installing the hydraulic pump of the plate bending machine, check whether the depth of the installation emulsion is greater than the auxiliary extension length of the pump to prevent shaft lifting, otherwise the pump will be burned.
② Precautions for using the hydraulic pump of the plate rolling machine
a. When starting the hydraulic pump of the plate bending machine, pump it several times to make sure that the slag flow direction and sound are at normal pressure. Run it 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 drain sleeve on the shell 1:3.
b. The viscosity of the oil changes due to the influence of temperature. As the oil temperature increases, the viscosity decreases. Therefore, the oil temperature is required to be kept below 60°C. In order to ensure that the hydraulic pump of the plate bending machine can work stably at different operating temperatures, the selected The oil should have the characteristics that the viscosity is less affected by temperature changes, as well as good chemical stability and anti-foam properties. It is recommended to use L-HM32 or L-HM46 (GB11118.1-94) anti-wear hydraulic oil.
c. The oil must be clean and must not be mixed with mechanical impurities and corrosive substances. Hydraulic systems without filtering devices on the oil suction pipeline must be refueled to the fuel tank through an oil filter truck (filtration accuracy less than 25/m).
d. The maximum pressure and maximum speed of the hydraulic pump of the plate bending machine refer to the peak value allowed in a short period of time during use. Long-term use should be avoided, otherwise the life of the hydraulic pump of the plate bending machine will be affected.
e. The normal operating oil temperature of the hydraulic pump of the plate bending machine is 15-65℃. The maximum temperature on the pump casing is generally 10-20℃ higher than the oil temperature at the pump inlet in the tank. When the oil temperature in the tank reaches 65℃, The maximum temperature on the pump casing does not exceed 75--85℃.