During decarburization procedures the vacuum system needs to operate very long time in a tough pressure range. An efficient gas-cooling is necessary as the extracted hot gases would otherwise 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 specific vacuum environment. Simultaneously, the vacuum system utilized by these industries is certainly continuously increasing, and the vacuum level is continuously increasing. Furthermore, the state’s environmental security, energy saving and three wastes discharge to the above-talked about industries, etc. Certain Gas-Cooling Roots Pump china requirements are more stringent. At the moment, the existing dry vacuum pumps out there, such as for example screw vacuum pumps and claw vacuum pumps, cannot meet up with the requirements of oil-free large pumping rate clean vacuum environment proposed by these industries due to the restrictions of pumping rate characteristics and structural mechanism.
In view of the shortcomings of the existing technology, the technical problem to be solved by the utility model is to supply an all-gas-cooled vacuum system to satisfy the use in a clean vacuum environment with large oil-free pumping speed.