For the rotary vane vacuum pump, it must be divided into single-stage and two-stage. There is also a great difference in terms of single-stage and two-stage. For the oil seal rotary vane vacuum pump, we used to call the direct belt driven rotary vane vacuum pump, and directly connect the pump with the motor or connect it with a coupling, which is called the direct rotary vane vacuum pump.Here, we should pay attention to that for each pump, there are single-stage and two-stage. And in the single-stage pump, because the selected structural form and its parameters are different, the ultimate pressure of the pump and its purpose are also different.As far as the single-stage and bipolar rotary vane vacuum pumps are concerned, in terms of their common characteristics and their structure, they are actually relatively simple and convenient in terms of their use, that is, they can be started under atmospheric pressure, that is, they can be directly discharged into the atmosphere, and their eccentric mass is relatively small, In terms of its maintenance, it is also relatively simple. In terms of the structure of the pump itself, it is also improved. In this way, its reliability will be improved.In terms of the structure of the vacuum pump, in order to prevent oil return when the pump is stopped, a check valve that can automatically cut off the oil circuit will be set. However, in other terms, it will also be equipped with an air inlet channel stop valve. In addition, in order to automatically cut off the gas circuit to our pump port when the pump operates in the gas town and there is a sudden power failure, When it is in the state of vacuum rotary vane vacuum pump, in fact, it will be equipped with oil pump and control structure.For the two-stage rotary vane vacuum pump, it can also be widely used in refrigerators, air conditioners, light bulbs and fluorescent lamps. In addition, it can be used in bottle bladder production and electronics. In addition, it can be used in many industries such as metallurgy and medicine. Moreover, because the direct vacuum pump has no dust pollution caused by belt friction, its volume is relatively small and its weight is very light.