Roots pump pump working process

High-viscosity gear pumps, like Roots pumps, are used to convey media with high medium viscosity. Belongs to a type of vacuum pump without internal compression, usually low compression ratio, so high, the vacuum pump requires a foreline pump. In the course of their work, Roots pumps can be used in series. Taking an LC Roots pump for example, it works like a Roots blower. Due to the constant rotation of the rotor, the drawn gas is sucked into the space v0 between the rotor and the pump housing through the air inlet and then discharged through the air outlet. Since inhaled v0 space is completely closed state, so the gas in the pump chamber is not compressed and expanded. However, when the top of the rotor rotates over the edge of the exhaust port, when the v0 space communicates with the exhaust side, part of the gas bounces back into the space v0 due to the higher gas pressure on the exhaust side, causing the gas pressure to suddenly increase. When the rotor continues to rotate, the gas is discharged outside the pump. Roots pump in the pump chamber, the two "8" -shaped rotor perpendicular to each other mounted on a pair of parallel shaft, the gear ratio of 1 pairs of gear driven reverse rotation of each other in sync. Between the rotors, between the rotor and the pump housing to maintain a certain gap, you can achieve high-speed operation.