Before the mechanical vacuum pump needs to be shut down for maintenance, the connecting pipe of the mechanical vacuum pump must be disconnected first to ensure that the mechanical vacuum pump has been supplied with atmospheric pressure, and then the mechanical vacuum pump can be cooled. The vacuum pump oil in the pump can be drained first, and the oil in the pump is drained completely. After cooling for 20 minutes, the mechanical vacuum pump can be disassembled.

Mechanical vacuum pump routine maintenance and maintenance precautions

一、 Mechanical vacuum pump maintenance schedule

The maintenance interval of mechanical vacuum pump should be determined according to the use environment of vacuum pump. If the gas contains water, impurities, dust and other foreign matters, the vacuum pump must be frequently overhauled, otherwise, the maintenance schedule can be extended.

1. Daily maintenance items, check the oil quality and oil level in the pump

2. Maintenance items need to be done every week. Check whether the vacuum pump leaks oil. Clean the dust and foreign matters on the assembly and air inlet filter element with air gun.

3. Monthly maintenance items, check the exhaust filter (oil mist separator) function, whether there is smoke, fuel injection and other phenomena, if there is a problem, it is necessary to replace the vacuum pump exhaust filter.

4. Maintenance items should be carried out every 6 months. Check whether there is dust, dirt, carbon deposit and impurities in the vacuum pump cavity. If necessary, clean the vacuum pump, including oil tank, pump body, fan, fan wheel, ventilation grille and cooling fins.

5. Maintenance items for every 500 ~ 2000 hours: replace the vacuum pump exhaust filter, vacuum pump oil and vacuum pump oil filter, and check the float valve and oil return pipe in the pump.

When doing the above operation, please make sure that the vacuum pump is stopped.

二、 Inspection method of vacuum pump oil

If the pump oil is lower than the "Min" mark of the oil sight glass, check whether it is caused by process requirements.

The coloring of vacuum pump oil must be bright and clear. No foam or turbidity can be found. After the oil is precipitated, there is obvious milky white substance and black carbon crystal. Then the vacuum pump oil must be replaced and the same type of vacuum pump special oil should be added.

三、 Service life of vacuum pump oil

The service life of pump oil depends on the working environment in which the vacuum pump is located. When the clean and dry gas is extracted and the working temperature is lower than 100 ℃, the oil and oil filter must be replaced every 500-2000 working hours or every half a year. In a very bad working environment, the oil must be changed less than 500 working hours. If corrosive gas is pumped out, it must be specially designed Intake filter and special synthetic oil, if necessary, use fluorine oil.

四、 Replacement of vacuum pump oil and oil filter

1. Drain the oil from the vacuum pump. After cutting off the power supply of the vacuum pump for 20 minutes, make sure that the vacuum pump has been connected with atmospheric pressure. Find the oil drain port of the vacuum pump (under the oil sight glass), screw down the oil drain port to drain the vacuum pump oil. When the flow rate of the pump oil is small, restart the vacuum pump for several seconds, close the vacuum pump again, and then turn off the power supply of the vacuum pump again to drain oil. Repeat this action several times until the vacuum pump Drain the oil.

2. To clean the vacuum pump, the waste oil shall be drained first, and 2L cleaning fluid shall be prepared according to 50% vacuum pump oil, 50% paraffin or diesel fuel / fuel oil ratio; the oil drain plug shall be tightened, the cleaning fluid shall be injected into the vacuum pump, the air inlet shall be closed, and the vacuum pump shall be operated for at least 30 minutes; then the cleaning fluid shall be discharged and the discharged cleaning fluid shall be disposed according to environmental protection regulations.

3. Check the float valve: remove the joint between the oil return pipe and the oil tank, then remove the two screws of the float valve flange and take out the float valve from the oil tank; check whether the float valve is clean and damaged, and clean it with compressed air if necessary. During assembly, pay attention to that the sealing ring has been installed on the flange of float valve and is intact, and put the float valve in the correct position of the oil tank.

4. Replace the oil filter: drop lubricating oil on the sealing ring in the new oil filter, assemble and tighten it by hand.

5. New oil injection: screw off the oil filling plug and inject special oil for vacuum pump. Make sure that the oil level is between the "Min" and "Max" marks of the oil level mirror; tighten the oil filling plug with sealing ring.

五、 Exhaust filter

1. Inspection of vacuum pump operation: use exhaust filter pressure gauge to check whether exhaust filter is blocked. When the pressure gauge reading is in the red area, it indicates that the exhaust filter is blocked and must be replaced. If there is no exhaust filter pressure gauge, the resistance of the exhaust filter is determined by the change of the driving motor current. If the driving motor consumes too much current or the flow of the vacuum pump decreases, it indicates that the exhaust filter is blocked and must be replaced.

If the pressure indicated by the exhaust filter pressure gauge is lower than usual, or the driving motor consumes less current than usual, the reason is that one exhaust filter is damaged and the exhaust filter needs to be replaced. If the exhaust gas contains oil, the reason is that the exhaust filter is blocked or damaged, it must be replaced. The exhaust filter can not be cleaned thoroughly, and the blocked exhaust filter must be replaced.

2. Before replacing the exhaust filter, please turn off the vacuum pump and cut off the power supply to ensure that the vacuum pump has been supplied with atmospheric pressure. Open the cover plate of the exhaust port from the oil tank, and remove the exhaust filter with the help of the special inner six hand. Install the open end of the new exhaust filter with the sealing ring in the correct position in the oil tank.

六、 Overhaul of vacuum pump

In order to achieve the highest efficiency and longer service life of the vacuum pump, its installation and calibration have precise tolerances. Assembly and disassembly of vacuum, calibration tolerance will be lost. Therefore, disassembly and assembly must be provided by "professional vacuum pump manufacturer" company. Pollutants will remain in the pores, gaps and interior of the vacuum pump; disassembly and assembly of the vacuum pump containing pollutants will be harmful to health. When disassembling vacuum pump, operators must wear protective equipment.

七、 Vacuum pump out of service

1. Temporarily stop using: please turn on atmospheric pressure first, and then disconnect the pipe or air inlet.

2. Reuse: first remove the fan cover of the drive motor, rotate the fan wheel a few circles slowly by hand according to the rotation direction, and then install the fan cover. Turn on the power and start. If it is not used for a long time, the vacuum pump oil should be drained.