Rotary vane vacuum pump presents a trend of design improvement
1, material selection: to improve the rotary vane vacuum pump speed, reduce wear, reduce temperature, to ensure the normal performance of the pump, one of the keys is how to properly select the stator and rotary vane of the main friction pair of materials. Some domestic research units have also tested other materials as spiners, and the results show that it is of great value to use carbon fiber reinforced plastics and polymer liquid crystal materials as spiners.
2. Pump cavity profile: As the friction and wear between vane vacuum pump and stator increase, the temperature rise of vane vacuum pump increases, so improving the friction, wear and lubrication between vane vacuum pump and pump cavity is the key to develop a direct-coupled vane pump with good performance.
3. Rotor structure and rotary vane: According to the calculation of geometric pumping speed of rotary vane vacuum pump, when the pump speed has reached a certain high value, adding rotary vane can improve the pumping speed without increasing the rotor eccentricity or increasing the maximum linear velocity. It is also simple and feasible to increase the number of rotating blades in the structure, so it is a promising way to improve the pumping speed. At present, the rotary vane vacuum pump manufactured by domestic manufacturers has a three-slot integral rotor structure, which is equipped with three rotary plates. The structure of the integral rotor has higher strength and rigidity. It can reduce the unbalance of rotor in high speed operation to reduce the impact load of rotor.
4, the pump body structure and vent position side eccentric structure is a relatively new type of pump body structure. The side of the eccentric structure of the pump rotor and the cut-off point of the pump chamber is not on the top, but on the side, the oil tank is also on the side. It has the following advantages compared with the general upper cut point structure of the pump: because the oil level and the exhaust port in the side, and the oil level just put the exhaust valve and lubricating oil way of the oil inlet hole submerged, so stop the pump, can only return a little oil in the pump chamber, the rest of the oil can only return to the oil inlet hole can not be into the pump chamber. Because the amount of oil backflow to the pump chamber is very small, so the pump is easy to start, which can reduce the pump motor power. At the same time, when the oil returns to the inlet hole position, the inlet hole becomes the vent hole. Make the gas pressure in the pump equal to the external atmospheric pressure to prevent oil from returning into the vacuum system and causing pollution.
Rotary vane vacuum pump has many aspects to be improved. I believe, with the progress of vacuum technology, better performance, can adapt to a variety of process requirements of rotary vane pump will appear.