Valve manifold

Abstract

Instead of the usual three or five valves a valve manifold includes four valves, namely a pair of line block valves intersecting a longitudinally extending flow passage in the valve body for normally closing inlet passages, an equalizer valve between the line block valves intersecting the flow passage; below the equalizer valve is a vent passage and a vent valve in the vent passage. During operation the line block valves are open to promote the flow of process pressure to the measuring instrument and the equalizer valve is closed to prohibit the flow along the longitudinally extending flow passage. The vent valve is in the open position. By closing the line block valves with respect to the inlet passages, while leaving them open with respect to the flow and outlet passages, closing the vent valve and opening the equalizer valve permits the flow to be balanced between each side of the manifold. Upon opening the vent valve the manifold can be vented.

Dependencies are inferred from the claim text.