Summarization JZS series serew roots vacuum pump set is made up with the Roots pump and screw vacuum pump.Serew vacuum pump is used as the pre-vacuum pump and the backing vacuum pump of the roots vacuum pump. Features JZS series serew roots vacuum pump set is a completely dry system, it has no pollution to the pumped medium; It's not sensitive to the pumped medium steam or dust environment, it has have obvious advantages compared to the JZX series single stage rotary vane vacuum pump set or JZH series rotary piston vacuum pump set; Dry running, will not produce waste oil, waste water or smoke, is conducive to environmental protection, saving oil and water resources; High vacuum degree, single roots and serew tandem can reach the ultimate vacuum of less than 1Pa; The maintenance and cleaning of the pump set is convenient, because there is no contact and no wear in the pump cavity, the vacuum performance of the long-term use is basically unchanged; The gas is directly discharged from the pump, no pollution of water and oil, gas and solvent is convenient to recycle. Applications Widely used in chemical, pharmaceutical, electrical engineering, aerospace, vacuum coating, vacuum furnace, vacuum drying, vacuum pressure impregnation, vacuum metallurgy and so on.