Patent ID: 6923423

Claim:
A gate valve which comprises: a valve body which includes a stem bore that extends therethrough and a seat bore that extends therethrough and intersects the stem bore generally transversely; a stem which is disposed in the stem bore and which includes a first stem portion that is sealed to the stem bore and a second stem portion that is sealed to the stem bore; first and second seats which are each positioned at least partially within the seat bore and which each include a flow bore that extends therethrough; a gate which is operatively connected to the first and second stem portions and is disposed between the first and second seats; first actuating means for moving the gate from a first position to a second position; second actuating means for moving the gate from the second position to the first position; wherein one of the first and second positions corresponds to an open position in which a through bore in the gate is aligned with the flow bores in the first and second seats, and the other position corresponds to a closed position in which the through bore is offset from the flow bores; a first seat retaining flange which is secured to the valve body over a first end of the seat bore; wherein the first seat is retained in the seat bore between the gate and the first seat retaining flange; and wherein the first seat retaining flange comprises an integral metal seal which seals against the seat bore.