Gate valve

A slab gate valve assembly comprising a housing providing an inlet, an outlet, and a gated fluid passage between the inlet and the outlet, at least one valve seat disposed in the housing, a gate-carrying shaft, and a slab gate plate arrangement in slidable engagement with the at least one valve seat and to be operated via the gate-carrying shaft between an open condition and a shut condition, wherein at least one plate of the gate plate arrangement comprises a fluid aperture to provide a passage between the inlet and the outlet when in registration with the fluid passage, and a solid slab portion to cover the valve seat in the shut condition, and is mounted at one plate end to the gate-carrying shaft, via at least one connector component oriented across an axis of the gate-carrying shaft, to form a connection arrangement providing a non-circular cross-section, to limit axial movement of the gate plate relative to the gate-carrying shaft more than perpendicular movement thereof, to reduce slack when translating axial movement of the gate-carrying shaft to an axial movement of the gate plate, while permitting gate plate articulation perpendicular to the gate-carrying shaft, and wherein the at least one plate comprises a free end not mounted to the gate-carrying shaft, whereby the gate plate articulation relative to the gate-carrying shaft and the free end allow the at least one plate to float into a sealing contact abutment against the valve seat when moved between the open and shut conditions.