Vacuum pumps are widely applied in many industries with the deep development of modern science and technology. They can be used for scientific research, production and teaching in metallurgical, chemical, light industry, petroleum, medical, pharmaceutical, printing and dyeing, electrical appliances, semiconductor, food, atomic energy, textile and other scientific research institutions, colleges and universities, industrial and mining enterprises.There are two types of vacuum pumps that are most commonly used in above fields, which are diaphragm vacuum pump and rotary vane vacuum pump. But what are they and what is the difference between them?

Diaphragm Vacuum Pump VS. Rotary Vane Vacuum Pump

　　Diaphragm Vacuum Pump

A diaphragm vacuum pump is a kind of mechanical vacuum pump without the use of oil or liquid. It a new generation of high-tech product, with the advanced design, high efficiency and long service life.Generally a diaphragm vacuum pump is oil free with less maintenance. They work by moving a flexible diaphragm that forces air in through one side and out the other by controlling valves.It is not only an accessory product of the precision chromatography instrument but also one of the essential instrument in laboratories, widely used in the application scenarios of the water circulating vacuum pump and rotary vane vacuum pump as well as the medical and pharmaceutical product analysis, fine chemical, biochemical pharmaceutical, food inspection, criminal investigation technology and other fields. But a diaphragm vacuum pump can’t achieve as low vacuum as a rotary vane vacuum pump, which is not applicable for vacuum freezing and drying.

　　Rotary Vane Vacuum Pump

A rotary vane vacuum pump is a kind of positive-displacement pump, which is one of the basic equipment for removing gas from sealed containers. Generally, the gap between the rotary vane and the pump cavity is sealed by oil, so the rotary vane vacuum pump is usually regarded as a kind of oil-sealed mechanism vacuum pump.A rotary vane vacuum pump works by moving volumes of gas through the system and out of the outflow. It requires oil in the system to lubricate the moving parts and create a seal. As a result, a rotary vane vacuum pump requires more maintenance, such as oil changing.A rotary vane vacuum pump can achieve a lower vacuum than a diaphragm vacuum pump, which can be used with freeze dryers for vacuum freezing and drying.