1、 Reasons for adding water when vacuum pump is running

Vacuum pump in operation requires liquid as working fluid, which is basically water as the working fluid. When the impeller rotates clockwise, the water is thrown around by the impeller. Because of the centrifugal force, the water forms a closed ring with the same thickness which is determined by the shape of the pump chamber. The inner surface of the lower part of the water ring is just tangent to the impeller hub, and the upper inner surface of the water ring just contacts with the top of the blade (in fact, the blade has a certain insertion depth in the water ring) A crescent shaped space is formed between the hub and the water ring, and this space is divided into several cavities equal to the number of blades by the impeller. If the lower 0 ° of the impeller is taken as the starting point, then the volume of the small cavity changes from small to large when the impeller is 180 ° before rotation, and it is connected with the suction port on the end face. At this time, the gas is inhaled, and when the suction is finished, the small cavity is isolated from the suction port; when the impeller continues to rotate, the small cavity becomes smaller and the gas is compressed; when the small cavity is connected with the exhaust port, the gas is discharged from the pump. When water is reduced, its working efficiency will be reduced, which will increase energy consumption and increase operating costs. The function of working fluid is not only used to extract gas, but also to reduce the temperature of pump body. The working fluid is much lower than the normal level, which will increase the heat output of the pump body, reduce the durability of the pump and increase the maintenance cost. Therefore, the water ring vacuum pump must maintain the normal level of working fluid during operation, which is conducive to the normal operation of the pump, but also conducive to maintenance and reduce costs.

2、 Water adding procedure of vacuum pump

1. Cut off the power supply and unplug the power plug. If the pump is on the system, it should be removed from the equipment.

2. Screw the oil opening bolt to drain oil, and manually turn the belt pulley to drain all the remaining oil in the pump chamber. The oil should be collected well. Generally, an iron oil pan or disk is placed under the bottom plate of the mechanical pump for collection, so as to facilitate distillation recovery and avoid environmental pollution in the future.

3. Remove the belt, pulley and key, and disconnect the bottom plate. Repair the motor or send it to the electrician for oil washing according to the motor's quality (such as heating, dirty, dry grinding noise, large vibration, etc.).

4. First remove the low vacuum end cover plate (rear cover plate, that is, the end far away from the pump wheel), and use different tools according to different screws. For general hexagon screw, solid wrench can be used, and socket wrench should be used if necessary, so as not to damage the screw. After screwing the open cover plate screw, gently open the end cover plate. If the end cover plate is tightly closed, try to open it slowly. For example, file a small slot at the joint of the pump chamber and the end cover plate with a file, and then insert a driver (screwdriver) into the small slot and tap the handle of the driver by hand. You can also use a small hammer to tap the driver to exit the end cover plate. Do not hit it with heavy hammer.

5. If the rubber washer is used for sealing, remove the rubber washer and exit the locating pin.

6. Take out the rotor and rotor. Usually, there are two thread piercing daggers at the low rotor end, which can be easily pulled out by screwing in the thread rod. However, it should be noted that when pulling out the rotor, the rotating blade must be pinched tightly by hand. As the rotating blade is subject to large spring force, it is easy to fly out of hand, fall on the ground or hit hard objects, which will damage the edges and corners and surface of the rotor, resulting in endless scrapping.

7. Disassemble the high vacuum end in the same way as 4, 5 and 6, and take out the high rotor and rotor. At this time, the rotor can be taken out by simply pinching the rotating blade and shaft by hand.

8. Before dismantling the pump, the structural characteristics of the pump to be repaired and the structure type of each component should be understood in advance. For example, for those components that are components of the assembly, such as the rotors of some vane pumps, do not disassemble them, but make appropriate correction and adjustment on their surface; if the glass chips and metal foreign matters fall into the combined rotor and damage the cavity or the vane groove has been worn too much, the parts can be removed, but the assembly method should be remembered carefully.

9. Every time a component is removed, check its accuracy, finish and damage. Special attention should be paid to check whether the edges and corners of the rotor and rotor are damaged, and make records. For the pump repairers who are not familiar with the business, they should gradually remember the original location of each component and spare part, and make a record, so as to avoid mistakes when re assembling. At the same time, the removed parts should not be misplaced, piled up, damaged or lost. It is best to put it in a square disk, or put it in a wooden box and clean it, and cover it with silk cloth (if there is no silk cloth, cover it with smooth white paper at least).