The crude vacuum pump is mainly used to pump out air and other gases with certain corrosiveness, insoluble in water and small amount of solid particles. It is widely used in vacuum evaporation, concentration, impregnation, drying and other processes in food, textile, medicine, chemical and other industries. The vacuum pump is characterized by high vacuum degree, simple structure, convenient use, reliable operation and convenient maintenance.
According to the scope of use and pumping efficiency, vacuum pumps can be divided into three categories:
(1) In general, the pressure of water pump can reach 1.333-100kpa (10-760mmhg), which is “coarse” vacuum.
(2) The pressure of oil pump can reach 0.133-133.3pa (0.001-1mmhg), which is a “sub high” vacuum.
(3) Diffusion pump, the pressure can be up to 0.133Pa or below, (10-3mmhg) is “high” vacuum.
The oil-free (corrosion-resistant) vertical reciprocating vacuum pump is an updated product of the horizontal vacuum pump, and it is the main equipment to obtain the coarse vacuum. Due to the use of full sealing device, the crankcase and cylinder are completely isolated; in addition, the piston ring is made of self-lubricating material, so the advanced oil-free lubrication is realized.
Water ring vacuum pump is a kind of crude vacuum pump. The limit vacuum it can obtain is 2000 ~ 4000Pa, and the series atmospheric ejector can reach 270 ~ 670pa. Water ring pump can also be used as compressor, which is called water ring compressor. It belongs to low-pressure compressor, and its pressure range is 1 ~ 2 × 105Pa gauge pressure.
Working principle of water ring vacuum pump:
The water ring vacuum pump is used as a self-priming pump. It is composed of impeller, pump body, suction and exhaust disc, water ring formed by water on the inner wall of pump body, suction port, exhaust port, auxiliary exhaust valve, etc.
In many industrial processes, such as vacuum filtration, vacuum water diversion, vacuum feeding, vacuum evaporation, vacuum concentration, vacuum moisture return and vacuum degassing, water ring vacuum pump is widely used. Due to the rapid development of vacuum application technology, people have been paying attention to the water ring vacuum pump in obtaining the coarse vacuum. Because the gas compression in the water ring vacuum pump is isothermal, it can pump out inflammable and explosive gas, in addition, it can also pump out the gas containing dust and water. Therefore, the application of water ring vacuum pump is increasing day by day.