◆ The outer frame of air valve is rolled by high-quality galvanized steel plate / stainless steel plate. It has high strength and corrosion resistance, and can punch flange mounting holes for users.

◆ The blade is made of double-layer high-quality galvanized steel plate / stainless steel rolled into corrugating shape, and two pieces are welded together. It has the advantages of high strength, high static pressure resistance, high wind speed, etc.

The airtight air volume regulating valve has common type, temperature resistant type and heat preservation type, which can be selected by users. The air temperature range of the inflow air valve is: class I: - 40 ~ 95 ℃ class II: - 55 ~ 205 ℃ class III: ≤ 280 ℃

◆ Special material and type of sealing structure are adopted to ensure that the blades are sealed and reliable with low leakage when the air valve is fully closed. Silicon rubber products are used between the blades, which have good elasticity (shore 35-75 degrees), high and low temperature resistance (- 50-280 degrees C), and are not easy to aging and deformation.