Rubber lined centerline butterfly valves are widely used as load and break fluids in industrial pipelines such as metallurgy, power, petrochemicals, water supply and drainage, and municipal construction. 1. The centerline butterfly valve has an elastic interference seal that gives the valve bi-directional zero leakage performance. 2. The valve body adopts precision casting technology, with rubber lining to avoid contact with fluid media. Different rubber material combinations meet various working conditions. 3. Streamlined butterfly plate design+edge polishing provides lower operating torque and minimal pressure loss, ensuring long-term zero leakage sealing and valve seat life. 4. The flexible and versatile design of the whole shaft and half shaft, with and without pins, meets the needs of different customers. 5. The valve seat design adopts a backing and vulcanization structure according to different specifications, isolating the valve body and stem from the fluid and providing a seal to the pipeline flange without the need for additional sealing gaskets.