The roots pump and screw pump vacuum system is a dry vacuum system which consists of a roots pump as the main pump and a screw vacuum pump as a backing pump. The screw vacuum pump is connected with the roots vacuum pump, which increases the pumping speed exponentially and increases the ultimate vacuum degree. The roots screw unit has high vacuum degree and high vacuum efficiency. Through the supporting control system, the unit can start and stop automatically, and has automatic protection functions such as overload, over-current and water cut-off. The whole vacuum unit can be treated with anti-corrosion to pump corrosive gas. Each vacuum system adopts vertical stack structure or cascade structure, use small space and the middle line are not easily deposited,which in smoke gas containing a small amount of non-condensable gas or a small amount of dust conditions have obvious advantages.
According to the size of the pumping system and working pressure to allocate vacuum system, the ratio between each pump in the system can be selected 1:2 ~ 8, tatio increasing can reduce the extraction efficiency of vacuum pumps, reduce working pressure range and slow start.
Roots pump and screw pump vacuum system has high vacuum degree, wide range of working pressure and high extraction efficiency, can be widely used in pharmaceutical, chemical, aerospace, electronics, solar energy, metallurgy, food and other industries. The system is suitable for high vacuum distillation, vacuum evaporation and dehydration crystallization in chemical and pharmaceutical industries. Particularly in the chemical industry, unit roots screw is a good way to replace water ring instead of double roots and three units, has been widely applied in the market, the effect is obvious, environmental protection and energy saving.