The ultimate vacuum of the reciprocating vacuum pump (also known as the piston vacuum pump), the single stage is 4 X 102Pa--103Pa, the double stage can reach 1Pa, the pumping speed range is 45m3/h-20000m3/h, and it is used for pumping from the sealed container gas. The gas to be pumped does not exceed 35t, and if auxiliary equipment such as a refrigerator is added, the gas can also be pumped. The exhaust t of the reciprocating vacuum pump is relatively large, and it is mostly used for vacuum impregnation, vacuum treatment of molten steel, vacuum distillation, vacuum swallowing, vacuum concentration, vacuum crystallization, vacuum drying, vacuum filtration, and vacuum operation of concrete to extract gas.

Reciprocating vacuum pumps are not suitable for pumping corrosive gases or gases containing small particles of dust. If the pumped air contains dust, a filter must be installed at the inlet of the pump.

The oil-free reciprocating vacuum pump adopts the piston ring and sealing ring of self-lubricating material, so there is no need for lubrication in the cylinder; an oil separation chamber (its length is greater than one stroke length) is added between the cylinder and the body to prevent the lubricating oil in the body from moving along the piston rod. Leaky air cylinder, so the pump has no pollution to the pumped system. There are two types of oil-free reciprocating vacuum pumps, vertical and horizontal.

The scope of application of the pump is:
① In an environment that needs to be cleaned and vacuumed;
② When the gas poultry needs to be recycled, the gas can be filled in the gas chamber to ensure the purity of the gas;
③ When extracting flammable and explosive gases, the isolation chamber can be filled with inert gas so that the air (auxiliary agent) cannot leak out of the cylinder and avoid accidents.