1. There is a certain gap between the rotor and the pump cavity, the rotor and the rotor, and they do not contact each other and do not need to be lubricated with oil.

2. The rotor has good geometric symmetry, which can increase the speed, so as to produce a compact pump with high pumping speed.

3. When the pump is working, the vibration is small, the volume is large, and the volume utilization coefficient is about 0.5.

4. There is no compression in the pump chamber like a mechanical vacuum pump, so it does not need an exhaust valve. Because of this, condensable steam can be extracted.

5. Quick start, able to reach the ultimate vacuum in a short time. Low power and low operation and maintenance costs.

6. The Roots vacuum pump unit has a large pumping speed in a wide pressure range (1000Pa~1Pa), and can quickly discharge the suddenly released gas, which makes up for the pumping speed of the diffusion pump and the oil-sealed mechanical pump (1000Pa-1Pa). Small flaw. Therefore, it is suitable for use as a booster pump.