Technical Standards 

Design and Manufacture:API 609,MSS SP-67,MSS SP-68  Inspection and Test:API 598  End  flange dimension:ASME B16.5(NPS≤24),ASME B 16.47 B  BW end dimension:ASME B 16.25   Face to face and end to end:API 609   Pressure-temperature ratings:ASME B 16.34

Specification:

The seal principle of hard Seal Butterfly Valve triple offset:The Triple Offset Butterfly Valve provides a bi-directional bubble tight shut-off.This goemetry 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 auniform seal contact.

The triple offset geometry  OFFSET1 The shaft is offset behind the seat axis to allow complete sealing contact around the entire seat      OFFSET2 The shaft centerline is offset from the pipe and valve which provides interference free opening and closing of the valve        OFFSET3 The seat come axis is offset from the  shaft centerline to eliminate friction during closing and opening and to achieve uniform compressive sealing arount the entire seat.

Friction free sealing for long cycle life (1)Seat is Cr13 matal alloy or hardfaced with Stellite as standard.   (2)The gasket is spiral wound SS/Graphite for zero leakage.   (3)Seat ring forces are generated by the torque during closing uniformly around the entire circumference.The resilent seal fleses and energizes,assuming the shape of the seat,The compression forces equally distributed around the perimeter provide a tight bi-directional shut off. The resiliency of the seal allows the valve body and disc to contract or expand,without the risk of jamming duo to temperature flunctuations.It is self-adjusting.