Balanced stem gate valve

A gate valve mechanism comprising:

• a valve body having a valve chamber and inlet and outlet flow passages in communication with said valve chamber, annular seat carrier recess means being defined within said valve body about said flow passage means and forming a first annular abutment surface of generally planar configuration;
• gate means being movably disposed within said valve chamber and being movable between open and closed positions for controlling the flow of fluid through said flow passages;
• means for imparting opening and closing movement to said gate means;
• annular hard metal seat carrier means being disposed in interference-fitted relation within said seat recess means and defining a second annular abutment surface of generally planar configuration and an annular seat recess, said first and second abutment surfaces being oriented in substantially parallel relation;
• a substantially dead soft metal sealing ring being positioned within said seat carrier recess means and being in engagement with said first and second abutment surfaces, said dead soft metal sealing ring being of flat washer-like form and defining opposed annular flat surfaces being deformed by compressive engagement against said first and second abutment surfaces and establishing a seal between said valve body and said seat carrier means;
• a hard, wear resistant seat element being positioned within said seat recess and having sealing engagement with said gate means, said seat element cooperating with said seat carrier means to define an annular seal pocket therebetween;
• and
• annular resistant sealing means being disposed within said seal pocket and establishing a seal between said seat carrier means and said seat means.