Patent ID: 6386302
Filing Date: 2002-05-14
Classification: E21B

Abstract:
A reaming tool, comprising:a body having reaming blades affixed thereto at azimuthally spaced apart locations, said body adapted to be coupled at axial ends thereof to a drill string, selected ones of said reaming blades having cutters attached thereto at selected positions, an outermost surface of each of said reaming blades conforming to a radially least extensive one with respect to a longitudinal axis of said reaming tool of a pass through circle and a drill circle, said drill circle substantially coaxial with said longitudinal axis, said pass-through circle axially offset from said drill circle and defining an arcuate section wherein said pass-through circle extends from said longitudinal axis past said drill circle, so that radially outermost cutters disposed on ones of said reaming blades positioned azimuthally within said arcuate section drill a hole having a drill diameter substantially twice a maximum lateral extension of said reaming blades from said longitudinal axis while substantially avoiding wall contact along an opening having a diameter of said pass through circle.