Midline Wafer butterfly valve with rubber seals and seal in the form of the midline. Use pipe clamp flanges at both ends of the body. With easy installation and maintenance, a small opening and closing moments, sealing reliability, long life, wide application range of features. This series of butterfly valves are widely used in petrochemical, textile, papermaking, metallurgy, electric power industry, gas, liquid, semi-liquid pipeline regulation and closure for use. The valve structure length dimensions conform to GB12221-89 standard wafer butterfly. Detection methods conform GB/T13927-92 standards.