Manufacturer: Zhejiang Xinhai Valve Manufacturing Co., Ltd. Pneumatic hard seal butterfly valve utilized a U shape seal ring which is made of stainless steel. The elastic seal ring connect with eccentric disc which has been polished. The disc separates form sealing face when valve opened and connect with sealing face when valve closed to realize sealing, having the advantages of long service life and good sealing. Applicable temperature belows 550℃. Pneumatic hard seal butterfly valve is widely used for pipelines to regulate flow or closure fluid in metallurgy, petroleum, gas and other industries. Characteristics 1. The butterfly valve has simple structure, light weight and convenient utilization. 2. The valve utilizes U shape stainless steel seal ring, having elasticity. The seal ring, cooperating with disc, ensure the excellent seal with the disc, under low temperature or high temperature. 3. Three dimensional eccentricity of valve is calculated strictly. U shape seal ring has advantages of long service life and excellent seal. 4. Seal facing overlay with STL, has the advantages of wear resistance and long service life. 5. The valve has unique structure and is convenient to use. 6. Heat resistance, low temperature resistance and corrosion resistance.