Metering slot configuration for a valve spool

摘要

Metering slots in valve spools are useful for modulatably controlling fluid flow through a control valve. The current metering slot configurations used in a meter out condition have high flow forces acting on the spool or metering areas that open or increase in size rather slowly relative to the valve spool movement. The subject metering slot is formed by plunging a ball-end end mill cutter into a control face of a valve spool at an acute angle and then moving the cutter laterally to provide the desired width of the metering slot. The resulting metering slot provides a metering area that increases in size rather quickly with a rather small increment of movement of the spool with the flow forces generated by the fluid passing through the metering slot being relatively low.