Abstract: A reciprocating gate valve having an adjustable low stress stem connection structure (70) for connecting an operating stem (42) to a gate member (24). The connection structure includes a stem extension (78) formed on the bottom end of the operating stem (42) threadably receiving a collar (84) having an axial bore (86) coaxial with the stem (42) and extending therethrough receiving a gate extension (72) formed on the top end of the gate member (24). The collar (84) has a slot (96) extending generally perpendicular to the axial bore (86) in the direction of fluid flow through the valve. An adjusting nut (106) fits into the slot (96) and threadably engages the gate extension (72). The slot (96) permits movement of the nut (106) and gate member (24) relative to the longitudinal axis of the stem (42) in a direction generally parallel to the direction of fluid flow through to the gate valve.

Abstract: A double acting manual override mechanism for the hydraulic actuator of a subsea gate valve, and a visual indicator device for indicating the gate position. The gate is normally held open by hydraulic pressure and is moved by a spring to a fail closed position in the event of a malfunction. The override includes a drive nut threaded onto the valve stem and a drive sleeve which is telescoped on the drive nut and connected therewith by a series of splines. Spaced apart abutment surfaces are provided on the sleeve to limit axial movement of the drive nut on the valve stem in both directions. Rotation of the sleeve by means of an adapter is translated into rotation of the drive nut which contacts one of the abutment surfaces and thereafter effects axial movement of the valve stem to open or close the gate. The indicator device includes a watertight, transparent housing within which an indicator disc moves in response to movement of the gate.