During decarburization processes the vacuum system needs to operate very long time in a rough pressure range. A competent gas-cooling is necessary as the extracted warm gases would otherwise overheat the filter and vacuum system.

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 have to obtain a certain vacuum environment. At the same time, the vacuum system used by these industries can be continuously increasing, and the vacuum level is continuously increasing. Furthermore, the state’s environmental protection, energy conservation and three wastes discharge to the above-mentioned industries, etc. Certain requirements are more stringent. At present, the existing dry vacuum pumps in the marketplace, such as screw vacuum pumps and claw vacuum pumps, are unable to meet the requirements of Gas-Cooling Roots Pump oil-free large pumping quickness clean vacuum environment proposed by these industries due to the restrictions of pumping swiftness characteristics and structural system.

Because of the shortcomings of the prevailing technology, the technical problem to be solved by the utility model is to provide an all-gas-cooled vacuum system to fulfill the utilization in a clean vacuum environment with huge oil-free pumping speed.