Self-Restricting Shutoff Valve

摘要

This report describes a self-restricting shutoff valve for use with a fluid leak detector to prevent excessive loss of fluid in event of a high flow-rate leak. A valve spool within a valve body is spring-biased to a partial flow position and is maintained in an opened position by fluid pressure. Upon loss of fluid system pressure, springs move the valve spool to a position to restrict fluid flow through the valve body. When sufficient loss of fluid occurs, a fluid leak detector actuates a pilot valve so that system fluid moves the valve spool to a closed position. (Author)