Abstract: This relates to a ball valve of the top entry non-spherical type. A soft metal coating is deposited on that portion of the seat ring which contacts the valve member or ball. The ball and seat assembly is inserted into a valve chamber such that the seat rings are in an unstressed condition. After insertion, the ball is rotated 90.degree. causing the ball to engage the soft metal coating, thereby crushing the soft metal to form a tight seal with the ball. In this manner, the lapping process, generally required when metal seats are employed, is eliminated. Further, the seats may be replaced without replacing the ball.

Abstract: In a top entry ball valve, a ball having a bore therethrough is provided with chamferred edges around the periphery of the bore at both the inlet and outlet ends. In this manner, due to the geometric configuration of the valve seats, compression sealing takes place only when the valve is closed. When the valve is open, the chamferred edges merely engage the valve seats, thereby allowing easy insertion or removal of the ball/seat assembly.

Abstract: This relates to a ball valve of the top entry non-spherical type. A soft metal coating is deposited on that portion of the seat ring which contacts the valve member or ball. The ball and seat assembly is inserted into a valve chamber such that the seat rings are in an unstressed condition. After insertion, the ball is rotated 90.degree. causing the ball to engage the soft metal coating, thereby crushing the soft metal to form a tight seal with the ball. In this manner, the lapping process, generally required when metal seats are employed, is eliminated. Further, the seats may be replaced without replacing the ball.