First, the product description?? Air flow control valve is the company developed and produced a new type of air-flow valve, which combines the advantages of domestic and foreign air valve. Has a simple and reasonable structure, a small amount of leakage, low friction torque, rotating flexible blade rigid, corrosion-resistant, variety and so on. Its performance parameters and indicators exceed the JB / 7228-94 standards. Can be widely used in industrial and commercial air conditioning and ventilation systems in order to achieve precise control of air flow purposes. Second, the scope? Off more Yefeng flow valve, generally used in air conditioning, ventilation pipes used to regulate air flow manifold can also be used with the new wind? Back. Third, the model and the classification?? The series is divided into manual and electric valves, according to the tightness can be divided into a closed and non-closed two. Electric can automatically adjust the air volume control and automatic control system supporting.