Ring vacuum pump (referred to as water ring pump) is a rough vacuum pump, it can get the ultimate pressure, for a single-stage pump 2.66 ~ 9.31kPa; for two-stage pump 0.133 ~ 0.665kPa. Water ring pumps can also be used as compressors, which belong to the low pressure compressor, the pressure range (1 ~ 2) X105Pa gauge pressure (under specific conditions). Water ring pump in the petroleum, chemical, machinery, mining, light industry, papermaking, power, metallurgy, pharmaceutical and food industries and municipal and agricultural departments of many processes, such as vacuum filtration, vacuum feeding, vacuum degassing, vacuum Evaporation, vacuum concentration and vacuum regurgitation, has been widely used, as the water ring pump is compressed gas process isothermal, it can be extracted flammable and explosive gases, in addition to pumping out dust, water-containing gas Therefore, the application of water ring pump is increasing day by day. Water ring pump is composed of impeller, pump body, suction exhaust plate, water ring formed in the inner wall of the pump body, suction port, exhaust port, auxiliary exhaust valve and other components. The impeller is eccentrically installed in the pump body, when the impeller rotates in the direction as shown in the figure, the water entering the water ring pump body is thrown around by the impeller. Due to the centrifugal force, the water forms an equal thickness The closed water ring. The upper inner surface of the water ring is just tangential to the impeller hub and the lower inner surface of the water ring is just in contact with the top of the blade (in fact, the blade has a certain insertion depth in the water ring). At this point, a crescent-shaped space is formed between the impeller hub and the water ring, and this space is again divided into a number of small cavities equal to the number of blades by the impeller. If the upper part of the impeller 0 ° as a starting point, then the impeller 180 ° before rotation, the volume of the small chamber gradually from small to large (ie from the section â… -â… to â…¡-â…¡), the pressure continues to decrease, The suction port on the gas tray is communicated with each other. When the pressure in the small chamber is lower than the pressure in the container being pumped, according to the principle of gas pressure balance, the drawn gas is continuously drawn into the small chamber, process. When inhalation is completed and the suction port isolated from â…¡-â…¡ to â…¢-â…¢ cross-section, the volume of the small cavity is gradually reduced, the pressure continues to increase, this time in compression, when the compressed gas reaches the row in advance Gas pressure, exhaust from the auxiliary exhaust valve in advance. From sections III-III to I-I, the volume of the small chamber in communication with the exhaust port further reduces the pressure increase further, and when the pressure of the gas is greater than the discharge pressure, the compressed gas is exhausted from the exhaust port Discharge, in the continuous operation of the pump process, continue to inspiratory, compression, exhaust process, so as to achieve the purpose of continuous extraction. In the water ring pump, the auxiliary exhaust valve is a special structure, the general use of rubber ball valve, its role is to eliminate over-compression and under-compression caused by the pump during operation. Both of these phenomena cause excessive power consumption. Because the water ring pump does not have a direct exhaust valve, and the exhaust pressure is always constant, the water ring pump's compression ratio is determined by the end of the intake port and the exhaust port. However, these two positions are fixed Unchanged, and therefore not suited to the needs of changes in inhalation pressure. In order to solve this problem, the rubber ball valve is generally arranged below the exhaust port, so that when the pump chamber reaches the exhaust pressure prematurely, the ball valve is automatically opened and the gas is discharged, thereby eliminating the over-compression phenomenon. Water ring pump is generally designed to determine the lowest suction pressure to determine the compression ratio, in order to determine the starting position of the exhaust port, thus solving the phenomenon of insufficient compression.