Our country hydraulic industry enterprises to accelerate technological innovation, and constantly improve the market competitiveness of the products, a number of high-quality products for the success of national key projects and key supporting host, achieved good economic and social benefits. At present, there are more than 1 thousand enterprises with a certain scale in China's hydraulic industry, of which more than 300 are the main enterprises. The project of the national west east gas transmission project, Dalian hydraulic parts factory and Changzhi Shanxi hydraulic parts factory, is the key component in the steering system of medium and heavy duty truck. At present, the annual output has reached more than 100 thousand units. Tianjin Jing special Limited by Share Ltd hydrostatic transmission and multi valve, Huzhou Shengli hydraulic company multifunctional Fengyang hydraulic slide valve, Guizhou company, Wuxi Hefeng mechanical equipment factory hydraulic equipment etc., are praised by users. Thus it can be seen that the status and function of hydraulic transmission products are very important in national economy and national defense construction. It can not only meet the requirements of the diversification of mechanical and electrical products, but also is the basic guarantee for the completion of major projects and major technical equipment.