The nominal diameter of products in this series ranges from 20 mm to 200 mm, with nominal pressures of 1.0, 1.6, 4.0, and 6.4 MPa. The operating temperature range is from -250℃ to 450℃, and the received signal is 0～10 mA.DC or 4～20 mA.DC. The electric double-seat control valve is suitable for occasions with large pressure differences. According to the material of the sealing part of the valve inner components, there are two types: metal-metal sealing and non-metal-metal sealing. The leakage rate of the latter when the valve is closed can reach the Class Ⅵ (zero leakage) standard. According to different packings, it can be divided into general packing seal and bellows seal. The former is used in general occasions, while the latter is used in special occasions where external leakage is not allowed. The flow characteristics are linear or equal percentage. With different actuators, it can be divided into ordinary type and electronic type. A variety of specifications are available for selection.