Subsurface drilling tool

摘要

An improved subsurface drilling tool comprises a shank having a cutting end opposite a pin end configured to attach to a drill string. A plurality of ear portions is associated with the proximate end of the shank and configured to form a socket. A ball-shaped cutting tool is configured to fit inside the socket and is rotatably attach to the ear portions via an axle. A locking pin may be installed within one or more of the ear portions and perpendicular to the axle. A plurality of blade inserts is connected to the ball-shaped cutting tool. The blade inserts may be removable and/or configurable to be oriented in varied directions. A series of milling courses may extend longitudinally along an outside length of the shank. A fluid course may extend longitudinally within the shank to deliver drilling fluid to the cutting end.

主权项

1. A drill bit, comprising:
a shank, wherein the shank comprises a cutting end and an opposite pin end configured to be attached to a drill string; a plurality of ear portions disposed proximate to the cutting end of the shank and configured to form a socket, at least one of the plurality of ear portions having a locking pin hole configured to receive a locking pin; a ball-shaped cutting tool comprising a plurality of cones partially recessed within the socket; milling courses separated by ridges extending outwardly from the shank, wherein the ridges have a planar surface substantially aligned with a plane separating the plurality of cones; wherein the ball-shaped cutting tool is rotatably attached to the plurality of ear portions via an axle; wherein the locking pin is perpendicular to the axle; and wherein the plurality of cones rotates in opposite directions around the axle while the drill bit is drilling.