Operation problems of roots vacuum pump

In general, Roots pump will have this situation when pumping gas containing a lot of water vapor, and the oil seal is prone to problems. It is an exothermic phenomenon that water vapor changes from gas to water. Roots pump will generate heat and oil seal will rise. At this time, the pump has negative pressure and the gearbox has atmospheric pressure, so water vapor will be forced into the gearbox.

Usually, when designing a two-stage Roots unit, the front pump is designed into two paths: one path leads to the system pipeline (in parallel with the main pump Roots pump); One path is connected with Roots pump. At the beginning of pumping a large amount of water vapor, the roots pump was not used, and the front pump was used directly, so the gas volume was reduced. When the gas volume decreases, the water vapor will decrease, and then the Roots pump will not release heat, which improves the vacuum degree of the system.

This means that the pumping capacity of the backing pump cannot be selected according to the configuration ratio of the normal Roots unit, but should be enlarged or selected according to the pumping capacity of the system.