Control Valves and Drains
Examples of Indicating Control Valves
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Outside Stem and Yoke Valve The outside stem and yoke valve is the most common type of indicating valve. The valve operates by raising and lowering a gate that cuts off the water flowing through the valve casing. The gate connects to a large brass threaded stem with a circular threaded handle that connects to the yoke. As the operator rotates the handle counterclockwise, the stem extends further and further out of the handle, indicating the relative degree of the gate opening. As the operator rotates the handle clockwise, the threaded stem moves back into the valve and presents a lower profile. When the stem is no longer protruding beyond the handle, the gate valve is closed. Post Indicator Valve Located outside a building, the post indicator valve extends up from the ground over a water-supply main. As a detachable hand crank operates the valve, a tag connected to the stem reveals the word “open” or “shut” in a window on the side of the valve housing. You can lock the hand crank and the valve itself in position using a padlock or chain. |
Outside stem and yoke valve in open position
Outside stem and yoke valve in closed position
Post indicator valve in open position |
