When operating the imported vacuum pump, pay special attention to the following ten points:
1. Before using the imported vacuum pump, ensure that the pump is clean and prevent dirt from entering the pump. Check the oil quantity, and it is advisable to fill the oil to the oil level gauge when the pump is stopped. If it is too low, the automatic exhaust valve cannot seal the oil and affect the vacuum degree. If it is too high, it will cause fuel injection when starting from the atmosphere. When running at high speed, the oil level will increase further, which is a normal situation. Oil selection requires clean vacuum pump oil, which is added from the oil injection hole. After refueling, the oil plug should be screwed on. The oil should be filtered through the filter system to prevent dirt from entering and blocking the oil inlet. When refueling, add vacuum pump oil according to the scale indicated by the oil level gauge. Turn the three-way valve to make the suction pipe of the pump communicate with the atmosphere, block it from the evacuated container, and open the air outlet.
2. When the working temperature is too high, the ambient temperature of the oil will rise, the viscosity will decrease, the saturated vapor pressure will expand, and the vacuum will be formed and then reduced, especially the total pressure measured by the thermocouple meter. The vacuum limit can be alleviated by improving the exhaust air for heat dissipation or improving the pump oil characteristics.
3. The imported vacuum pump should not be used to remove the gas with high oxygen content, explosiveness, and corrosion to metal materials. On the other hand, it is also not suitable to inhale gases that can react chemically with pump oil and gases with a large amount of water vapor.
4. The pump can be started next time in the atmospheric environment or at other vacuum degrees. If a solenoid valve is installed at the pump port, it should be operated together with the pump.
5. After the pump operates normally, turn the three-way valve slowly to make the suction pipe of the pump communicate with the evacuated vessel and block it from the atmospheric environment.
6. Rotate the pulley by hand, and check the rotation details regularly. After there is no abnormal phenomenon, turn on the switch power supply, and pay special attention to the rotation direction.
7. After using it for a period of time, the transmission belt becomes more and more loose, and the adjustment of the position of the motor should be done. Pay special attention to replenishing the pump oil. When you find that the pump oil is stained with dirt or water, you should replace it with new oil, clean the pump body, and avoid cleaning the pump body with liquids of volatile organic compounds such as acetic acid and acetone.
8. Check the vacuum degree of the imported vacuum pump based on the compressed mercury vacuum gauge. If the meter has undergone sufficient pre-pumping tests, the pump temperature is stable, the pump port and the meter are connected at the same time, and the vacuum degree will be reached within three minutes of operation, The value measured by the total pressure gauge is related to the pump oil and vacuum gauge and the deviation of the regulation, and sometimes the error value may be too large.
9. If the relative humidity is high, or the pumped gas contains more condensable steam, after connecting the pumped container, it is advisable to open the gas ballast valve, and close the gas ballast valve after 20–40 minutes of movement. Before stopping the pump, the gas ballast valve can be opened for 30 minutes without load to prolong the life of the pump oil.
10. When the imported vacuum pump is stopped, in order to maintain a certain degree of vacuum in the vacuum system, the three-way valve should be rotated to block the vacuum system, and the suction pipe of the pump should be connected to the atmosphere. Turn off the power and stop the operation. Close the exhaust port and cover the pump tightly.
