CDG control valves are widely used in petroleum, chemical, electric power, metallurgy, mining, urban construction, water conservancy, shipbuilding and many other fields. It can be divided into two types: unbalanced and balanced. The valve body adopts unique technology to cast the contour of the air inlet principle in the valve body inlet and outlet, so that the fluid entering the valve can be evenly distributed on the valve cage, so that turbulence and other unstable factors can be reduced to the minimum, thereby improving the flow capacity of the valve. At the same time, the turbulence of the valve outlet reduces the noise and valve body wear to a minimum, and a variety of interchangeable valves can be fixed and fixed. The characteristic curve valve cage gives users more choices. It is admirable in the aspects of high quality, high performance, low weight and easy maintenance, and at the same time, it has the advantages of single seat valve and sleeve valve. It has all the functions of high adjustment precision, large cut-off pressure difference and small leakage. It is especially suitable for small working conditions with small leakage and high pressure difference. It can completely replace the traditional single seat valve, double seat valve and fine series control valve.