Piloted milling tool

Claim 1

A MILLING TOOL FOR PERFORMING AN ENDWISE CUTTING OPERATION ON THE UPPER END OF A TUBING LOCATED IN A WELL BORE COMPRISING A GENERALLY CYLINDRICALLY SHAPED BODY ADAPTED TO BE CONNECTED TO AN OPERATING STRING FOR ROTATION AND LOWERING WITH THE STRING IN THE WELL BORE TO POSITION THE BODY WITH ITS LOWER END EXTENDING INTO THE UPPER END OF THE TUBING IN SUBSTANTIALLY CONCENTRIC RELATION THERETO, LONGITUDINALLY EXTENDING, PERIPHERALLY SPACED, CUTTER ELEMENTS ON THE BODY HAVING LOWER END PORTIONS EXTENDING RADIALLY OUTWARDLY FROM THE BODY TO POSITIONS FOR GUIDING ENGAGEMENT WITH THE INNER SURFACE OF THE TUBING WHEN THE BODY IS INSERTED INTO THE UPPER END OF THE TUBING TO CENTER THE BODY IN THE TUBING, SAID ELEMENTS HAVING CUTTING PORTIONS LOCATED ABOVE AND EXTENDING RADIALLY OUTWARDLY BEYOND SAID LOWER END PORTIONS IN POSITION FOR ENDWISE ENGAGEMENT WITH SAID UPPER END AND PORTIONS LOCATED ABOVE AND EXTENDING RADIALLY OUTWARDLY BEYOND SAID CUTTING PORTIONS AND WHOSE OUTER EXREMITIES ARE DISPOSED FOR MOVEMENT IN A CIRCULAR PATH WHOSE DIAMETER IS LESS THAN THE DIAMETER OF THE BORE.