1. The principle is different

Roots vacuum pump (hereinafter referred to as roots pump) is a variable volume vacuum pump with two blades rotating synchronously in opposite directions. There is a small gap between the rotors, between the rotors and the inner wall of the pump shell.

An eccentric rotor with fixed blades is installed in the water ring vacuum pump. The water (liquid) is thrown to the stator wall. The water (liquid) forms a liquid ring concentric with the stator. The liquid ring and the rotor blade form a variable volume rotary variable volume vacuum pump.

2. The scope of application is different

Roots vacuum pump has been tested in petroleum, chemical, plastic, pesticide, steam turbine rotor dynamic balance, aerospace space simulation and other devices for a long time, so it should be vigorously promoted and applied in China. It is also widely used in petroleum, chemical, metallurgy, textile and other industries. Vacuum pump accessories for vacuum pump noise control, vacuum pump muffler.

Water ring vacuum pump is mainly used in coal mine (gas drainage), chemical industry, pharmaceutical industry, mining, papermaking, food, beer, building materials, plastics, metallurgy, electrical appliances and other industries.

3. Different characteristics

The characteristics of Roots vacuum pump are: fast start-up, low power consumption, low operation and maintenance costs, high pumping speed and high efficiency. It is not sensitive to a small amount of water vapor and dust contained in the extracted gas. It has a large pumping rate in the pressure range of 100 ~ 1 pa, which can quickly remove the gas suddenly released. This pressure range is just between oil sealed mechanical vacuum pump and diffusion pump. Therefore, it is often connected in series between the diffusion pump and the oil sealed mechanical vacuum pump, which is used to increase the pumping volume in the middle pressure range. At this time, it is also known as the mechanical booster pump.

The advantages of the water ring vacuum pump are simple structure, low manufacturing accuracy, easy processing, compact structure, high speed pump, generally can be directly connected with the motor, without deceleration device. Therefore, with a small structure size, large exhaust volume can be obtained, the floor area is small, the suction is uniform, the work is stable and reliable, the operation is simple, and the maintenance is convenient, but the disadvantage is that the efficiency is low, generally about 30%, the better can reach 50%, and the vacuum degree is low.