Abstract: Annular angulated spring-like seat rings of a floating or trunnion type ball valve are positioned within the angulated seat recess and define inner and outer circular edges, an annular face sealing surface and an annular back face sealing surface. The seat rings each establish annular face sealing with the spherical sealing surface of said valve ball and annular sealing with the annular angulated seat recess surface. The inner periphery of each annular spring-like seat ring is defined by an annular radiused edge providing a smoothly contoured annular internal edge surface establishing initial sealing with the valve ball and minimizing the potential for erosion of the spherical sealing surface of the valve ball during opening and closing rotation of the valve ball. The valve mechanism is provided with a valve stem actuator and a spring cover with adjustable stem rotation stop.

Abstract: Annular spring-like seat rings of a floating or trunnion type ball valve are positioned within the angulated seat recess and define inner and outer circular edges, an annular face sealing surface and an annular back face sealing surface. The seat rings each establish annular face sealing with the spherical sealing surface of said valve ball and annular sealing with the annular angulated seat recess surface. The inner periphery of each annular spring-like seat ring is defined by an annular radiused edge providing a smoothly contoured annular internal edge surface establishing initial sealing with the valve ball and minimizing the potential for erosion of the spherical sealing surface of the valve ball during opening and closing rotation of the valve ball. The valve mechanism is provided with a valve stem actuator and a spring cover with adjustable stem rotation stop.