Patent ID: 6021858
Filing Date: 2000-02-08
Classification: E21B

Abstract:
A steel body PCD bit comprising:a steel body having one end adapted to be connected to the lower end of a drill string, and an opposite end forming a face facing the bottom of a borehole;a plurality of steel blades integrally formed on the end face, at least one blade extending substantially radially outward from the centerline of the end face, said one blade having a bottom surface facing the bottom of the borehole, said bottom surface being divided into a forward section extending upwardly at an angle to an apex and a rearward section extending from said apex rearwardly downwardly at an angle thereto, said forward section having at least one socket extending therethrough; said blade further having a back surface that is chamfered at an angle with respect to the rearward section to provide additional relief to the flow passing over the blade andat least one cylindrical PCD cutter mounted within said socket and extending outwardly in a forward direction, said cutter having a back face facing said socket, and a front face at the opposite end thereof.