Roots pump, also named as roots booster, its main function is increasing vacuum pressure. Single roots pump can reach 5*10-2Pa, suitable for application with working pressure ranging 103~10-1Pa.
But traditional roots pump cannot be started separatly, it should be supported by mechanical pump (also named as fore pump). And they can achieve varied pressured when working with different type of mechanical pump. Hence in mechanical pump selection process, except for working environment request, working pressure should be considered as well. Below sheet is ultimate pressure of roots pump with regular mechanical pump for reference:
Explanation in real case:
A vacuum coating plant have a vertical chamber in Ø 1.20 m *1,20 m. The roots pump system should achieve 3~4torr (300~400 Pa) within 2mins.
A system including ZJP1200 roots pump and H150 rotary piston pump is provided, general power is <18.5Kw only (traditional power consumption reaches 26Kw ). The roots pump system achieves 2.5*10-1Pa within 30sec after roots pump started, much better than customer request.
Below is system photo from customer:
Edited by Shell Hu / EVP Vacuum Solution