Oil contamination caused by high-temperature decomposition and volatilization is one of the main sources of pollutants in oil-sealed vane pumps.
Installing an oil mist filter for the vacuum pump can effectively prevent this type of pollution. Additionally, the pumping speed of a vane-style vacuum pump is not constant; it changes with various factors.
A decrease in pumping speed significantly prolongs the time required to reach ultimate vacuum and increases energy consumption. To know how to increase the pumping speed of a vane-style vacuum pump, it’s necessary to understand what factors affect its pumping speed. Below,
BTLAS will share some methods to improve the pumping speed of a vane pump based on these influencing factors.
A vane pump operates under initial atmospheric pressure. As the pumping time increases, the vacuum level within the evacuated container gradually rises, while the actual pumping speed of the vacuum pump decreases. When the container reaches ultimate vacuum, the pumping speed becomes zero. The reasons for the continuous decline in actual pumping speed include pipeline flow resistance, oil leakage, and oil vapor reflux. Oil vapor reflux is the primary influencing factor. To increase pumping speed, it’s essential to control the reflux phenomenon. An oil mist separator for the vacuum pump can filter oil mist, achieving clean and environmentally friendly emissions while also making exhaust more efficient.
During the first period after startup, the pressure inside the container is relatively high, and the gas density is large, leading to relatively large resistance to oil vapor reflux.
However, as the vacuum level within the container increases, reflux occurs. Improving its exhaust capacity is key at this point, so installing an oil mist separator with smooth exhaust and low pressure drop should be considered. As the reflux rate of the vane pump continues to rise, its pumping speed will continue to decrease.
Methods to reduce reflux and increase the pumping speed of the pump include:
- Optimized structural design: Using molecular sieves or activated alumina adsorption traps can absorb oil vapor. Alternatively, combining an adsorption pump with a vane pump allows the adsorption pump to perform pre-evacuation.
- Using the recommended vacuum pump oil from the manufacturer: Using suitable high-quality vacuum pump oil often has a lower oil vapor pressure, reducing reflux at the source.
An oil mist filter for a vane pump resolves smoking and oil spraying issues in oil-sealed vane pumps, improving the performance of the vacuum pump and extending its service life. With smooth exhaust, reflux will be reduced.