Roots pump (Roots vacuum pump), also known as mechanical booster pump, is a rotary variable capacity vacuum pump without internal compression. It uses two "8" shape rotor in the pump shell rotation and the role of suction and exhaust, because it works in the low pressure range, the free path of gas molecules is large, the resistance of gas leakage through the small gap is great, so it can obtain a higher compression ratio, can be used as a booster vacuum pump; However, it cannot directly discharge the gas into the atmosphere alone. It needs to be used in series with the front stage vacuum pump. The pumped gas is discharged into the atmosphere through the front stage vacuum pump. It can be used with screw pump, water ring pump, slide valve pump, rotary vane pump, etc., working in a wide range of pressure. It can be seen from the characteristic curve that when the pressure is 1330 ~ 1.33pA, the pump has the maximum pumping speed.

Working pressure: 1.33×103 ~ 0.133Pa, depending on the primary pump.

Pumping speed: 150 ~ 5000L/s.

Speed: 3000 ~ 1500r/min.

The gas extracted by roots pump shall be filtered to prevent condensate and dust particles from adhering to the surface of the rotor and pump housing, which may cause motion obstruction or even damage of the rotor.

In recent years, the roots pump is widely used in vacuum metallurgy industry of the vacuum degassing, vacuum smelting, steel vacuum processing and spatial simulation, such as low density wind tunnel device of the corrosive gas, in addition, the roots pump can also be used in chemical, food, medicine, machine manufacturing and other industrial production process such as distillation, dry.