of a valve assembly 100 pumping fluid at or above a maximum flow rate to deactivate the differential fill feature the fluid as illustrated by arrow 215 initially enters the upper housing 105 in the valve assembly 100 the fluid flows through the passageway 185 and acts upon the orifice 175 and exerts a force that urges the locking sleeve 170 axially downward at the maximum flow rate the locking sleeve 170 is urged sufficiently downward to completely expose segments 110 upon exposure of the segments 110 the biasing member 165 causes the lower end of the segments 110 to move radially inward and the upper end to pivot in the groove 107 as the segments 110 move radially inward the locking shoulder 112 wedges against surface 172 of the locking sleeve 170 thereby preventing the locking sleeve 170 from moving axially upward in the valve assembly 100 as the locking sleeve 170 moves axially downward it also compresses the sleeve biasing members 115 against the seat 160 the force on the seat 160 by the sleeve biasing members 115 causes the seat 160 to move axially downward until the bottom of the seat 160 hits a stop 220 in the lower housing 120 the fluid as illustrated by arrow 215 continues through the.