3 EMPLOYEES WERE PULLNG FM#3 FK PUMP SCREW. ONE EE WAS USING A 5' PRY BAR TO MOVE THE SCREW FORWARD AND INJURED EE WAS HOLDING THE LOCKING COLLAR. THE LOCKING COLLAR BIT FAST TO THE PUMP SCREW SHAFT AND MOVED WITH THE SCREW PINCHING FINGER BETWEEN THE LOCKING COLLAR ADN SCRWE BEARING HOUSING.