ZheJiang Hisun Automation Instrument Co.,Ltd

Overview Features and Advantages Stem Blow Out Prevention Ring Prevent stem ejection in accidental working situation. Replaceable Disc Seal Reduce field maintenance costs. Live Loading Packing Gland Standard low emission stem seal with 0-20 PPM live-loading provides predictable and constant packing compression for more than 5000cycles before adjustment or re-packing. Metal-to-Metal Patented Sealing System Stellite Alloy HRC 40-60° Disc Position indication Stem end provides fool-proof verification of disc location. Universal Mounting Actuator Mounting Plate and Stem Connection conform to ISO5211 Principle Of Operation The SDF Triple Offset Butterfly Valve provides a bi-directional bubble tight shut-off. This geometry ensures that the disc seal contacts the body seat only at the final shut-off position without rubbing or galling, providing a torque generated resilient seal with sufficient“wedging”to ensure a uniform seal contact. THE TRIPLE OFFSET GEOMETRY OFFSET 1 The shaft is offset behind the seat axis to allow complete sealing contact around the entire seat. OFFSET 2 The shaft centerline is offset from the pipe and valve  which provides interference free opening and closing of the valve. OFFSET 3 The seat cone axis is offset from the shaft centerline to eliminate friction during closing and opening and to achieve uniform compressive sealing around the entire seat.