Patent ID: 7108082
Filing Date: 2006-09-19
Classification: E21B,E21C

Abstract:
1. A blade assembly for use in conjunction with a body of a reamer to facilitate enlargement of a bore of a subterranean pilot hole, the blade assembly comprising: an inner blade having a first extremity, a second extremity, and a central portion between the first and second extremities, wherein the inner blade is shaped to lie along the body for attachment thereto, wherein the inner blade comprises a plurality of circulation openings distributed along a length of the inner blade in alignment with a plurality of circulation openings of the body to permit passage of drilling fluid from an interior of the body to the outer blade; an outer blade having a first extremity, a second extremity, and a central portion between the first and second extremities, wherein the inner and outer blades are attached together such that the first extremities are adjacent to each other, the second extremities are adjacent to each other, and the central portions are spaced apart such that a gap remains between the central portions.