<p>SLIDING GATE VALVES Sliding gate valve for molten material includes fixed upper and lower valve plates 6, 8 and a movable valve plate 7 between them which has two flow openings 31 in it. Passive steering members comprising parallel guide arms 15 (Fig. 2) are arranged to guide the movable valve plate selectively in one of two directions x, y. The guide arms are switchable between two positions when the valve is closed so that a single linear actuator 23 connected to the movable plate may move the latter selectively in either of the said two directions to bring one or other flow opening in the movable plate into registry with the flow opening 5 in each fixed plate.</p>
