During decarburization processes the vacuum system must operate long time in a rough pressure range. An efficient gas-cooling is necessary as the extracted popular gases would otherwise overheat the filter and vacuum program.
With the development of technology and the improvement of product quality in aerospace, electric power, iron and steel processing, pharmaceutical and chemical industries, these industries need to obtain a certain vacuum environment. At the same time, the vacuum system used by these industries is definitely continuously Gas-Cooling Roots Pump increasing, and the vacuum degree is continuously increasing. Furthermore, the state’s environmental security, energy saving and three wastes discharge to the above-stated industries, etc. Certain requirements are more stringent. At present, the prevailing dry vacuum pumps on the market, such as for example screw vacuum pumps and claw vacuum pumps, cannot meet the requirements of oil-free large pumping velocity clean vacuum environment proposed by these industries due to the restrictions of pumping rate characteristics and structural mechanism.
Because of the shortcomings of the existing technology, the specialized problem to be solved by the utility model is to supply an all-gas-cooled vacuum system to fulfill the utilization in a clean vacuum environment with 
large oil-free pumping speed.