With the development of vacuum applications, many types of vacuum pumps have been developed, with pumping speeds ranging from a few tenths of a liter per second to hundreds of thousands and millions of liters per second.
As vacuum technology has wider and wider requirements for its application pressure range in the field of production and scientific research, most of them need to be composed of several vacuum pumps and vacuum pumping systems can meet the requirements of production and scientific research processes. The range of working pressure involved in the application department is very wide, so any type of vacuum pump cannot be completely suitable for all working pressure ranges. Different types of vacuum pumps can only be used according to different working pressure ranges and different working requirements. . In order to facilitate the use and the needs of various vacuum processes, sometimes various vacuum pumps are combined according to their performance requirements and applied in unit type.
