During decarburization procedures the vacuum Gas-Cooling Roots Pump china system needs to operate very long time in a rough pressure range. An efficient gas-cooling is necessary as the extracted hot gases would or else overheat the filter and vacuum system.
With the development of technology and the improvement of product quality in aerospace, energy, 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 is definitely continuously raising, and the vacuum degree is continuously increasing. Moreover, the state’s environmental safety, energy conservation and three wastes discharge to the above-pointed out industries, etc. The requirements are more stringent. At the moment, the prevailing dry vacuum pumps out there, such as screw vacuum pumps and claw vacuum pumps, are unable to meet the requirements 
of oil-free large pumping velocity clean vacuum environment proposed by these industries due to the restrictions of pumping speed characteristics and structural mechanism.
Because of the shortcomings of the existing technology, the technical problem to be solved by the utility model is to provide an all-gas-cooled vacuum system to satisfy the use in a clean vacuum environment with large oil-free pumping speed.