Butterfly valve and stem sealing assembly

摘要

A butterfly valve capable of preventing leakage under demanding environmental and operating conditions. The valve includes two stem seal assemblies. The stem seal assemblies include a first pusher, a first energizer, a second pusher, a second energizer, and a force transmitting member. The force transmitting member is configured to transfer an axial load to the second pusher, which causes the first and second energizer to expand radially to create a secondary and tertiary seals between the stem seal assembly and valve stem. In addition, the force transmitting member is configured to transfer an axial load to the first pusher which creates a primary seal.

主权项

1. A butterfly valve comprising:
a. a top body half, a bottom body half, and a flow-element positioned between said top body half and said bottom body half, b. a stem having a liner and secured to said flow-element and an actuator, wherein said stem extends through said top body half; c. a first stem seal assembly positioned substantially adjacent to said stem and configured to be seated within an annular space between the stem and the top body half; d. a second seal assembly is positioned between the bottom body half and the flow element e. a first pusher having a groove, wherein said first pusher is seated in the annular space; f. a first energizer positioned within the groove of the first pusher; g. a force transmitting member configured to transfer an axial force to said first pusher and said first energizer; h. wherein said first pusher is configured to enact a primary seal when subjected to said force; and i. wherein said first energizer is configured to expand radially when subjected to said force and thereby drive said stem and said first body half together to create a secondary seal, and wherein said secondary seal is configured to fluidly isolate said first energizer from said stem.