| 摘要 |
A valve has annular metal seats (26, 28) mounted in seat pockets (18, 20) around the inlet and outlet passage-ways (12, 14) at the valve chamber (16). Each of the seat members has a front face which includes an outer seal surface (36, 36a) around the outer perimeter of the seat and a flexible annular metal lip (38, 38a) around the inner perimeter of the seat. The lip has an inner seal surface (40, 40a) on its free end in spaced concentric relation to the outer seal surface (36, 36a) and maintains a fluid-tight seal with the closing member or gate (22, 24) while deflecting to compensate for deformations of the valve body (10) that would otherwise affect the seal. The inner peripheral surface of the seat has an annular groove (44) which defines the back surface (48) of the lip (38, 38a) which tapers from the base to the free extending end thereof. Each of the seat members (26, 28) has a back face which rests in contact with the outer peripheral portion of the bottom (32) of the associated seat pocket (18, 20). The seat member (26, 28) preferably has an annular flexible member (62) extending from its back face which may be welded to the valve body (10). The flexible lip (38, 38a) and flexible member (62) deform to compensate for deformations of the valve body (10) so the seat can maintain sealing contact with the gate (22, 24) when the valve is in the opened and the closed positions. |
