The stem is fully guided at both top and bottom with precision bushings for smooth and reliable operation. An advanced packing design with live-loading spring washers provides long-lasting stem tightness. An auto-lubricated thrust washer at the top of the stem reduces operating torque for easier actuation. The downstream seat is securely anchored—either seal-welded or pressed in place—to ensure perfect sealing under high pressure and temperature. Anti-blowout stem design prevents accidental stem ejection during maintenance or repacking. Coil springs and loading rings maintain consistent contact between the seat and ball, while allowing for thermal expansion in both open and closed positions. A one-piece body eliminates potential leakage at the body/closure and body/bonnet joints. A mechanical stop ensures proper ball orientation in both open and closed positions.
