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Oil-free vacuum pump refers to the vacuum pump chamber has no any medium (gas, liquid) mixed with the pumped medium, such as dry screw vacuum pump, dry rotary vane vacuum pump, scroll vacuum pump, Roots vacuum pump, claw vacuum pump, piston and diaphragm vacuum pump. Oil-free vacuum pump is also usually called dry vacuum pump.

 

With the continuous innovation and development of industrial chemical technology, the requirement of chemical process cleaning and environmental protection emission becomes more and more urgent. Some old vacuum pumps such as oil rotary vane vacuum pump, slide valve vacuum pump, etc., the consumption of vacuum pump oil, the discharge of lampblack, as well as the pollution of vacuum process medium, make it more and more unable to keep up with the development of chemical process, some production processes must use a clean and pollution-free vacuum pump.

 

Dry screw vacuum pump is an ideal vacuum pump type, the development of more perfect, high efficiency, and can achieve the wide application of high pumping speed, is worth promoting the vacuum pump. In some production processes instead of oil and liquid ring vacuum pumps have great advantages.