Abstract: A hole opener includes a body with cone arms. The body includes pockets formed in the body in which each of the pockets includes a forwardly-positioned shoulder pocket section, a rearwardly-positioned tapered pocket section and a base opening axially extending through a wall of the corresponding pocket that receives a fastener therethrough. The cone arms each include a cone head attached to an arm. The arm includes a forwardly-positioned shoulder arm section, a rearwardly-positioned tapered arm section, and a rearwardly-facing opening axially extending through the rearwardly-positioned tapered arm section that receives the fastener.

Abstract: A drill bit includes a bit body, a plurality of blades extending radially from the bit body, a plurality of cutter pockets disposed on the plurality of blades, at least one rolling cutter disposed in one of the cutter pockets, wherein each rolling cutter has a substrate, a cutting face, a cutting edge, and a side surface, and at least one blocker positioned adjacent to each of the at least one rolling cutters on a leading face of the blade, wherein each blocker has a retention end and an attachment end. The retention end of each blocker is positioned adjacent to a portion of the cutting face of each rolling cutter to retain the rolling cutter in the cutter pocket and the attachment end is attached to a portion of the blade.

Abstract: A cutting element for use with a drill bit includes a substrate having a longitudinal axis, a lateral surface substantially symmetric about the longitudinal axis and one or more key elements coupled to the lateral surface. The lateral surface lies between an insertion end and a cutting end of the substrate. The one or more key elements are substantially axially aligned with the longitudinal axis and configured to selectively rotationally locate the substrate in a pocket. A drill bit configured for retaining a cutting element having one or more key elements is also disclosed.

Abstract: The present disclosure relates to a microtunnelling apparatus including a cutting apparatus adapted to be rotated by a drill shaft defining a central axis of rotation that extends along a length of the drill shaft. The cutting apparatus includes a front cutting rotor having a hub defining a shaft receiver that extends at least partially through the hub in a direction extending from a back side toward a front cutting side of the front cutting rotor. The shaft receiver is configured to receive the drill shaft. The drill shaft and the shaft receiver cooperate to define a torque transmitting mechanical interface for allowing torque to be transferred between the drill shaft and the front cutting rotor such that the drill shaft can be used to rotate the front cutting rotor about the central axis of rotation. The front cutting rotor also includes a plurality of cutting bars that project at least partially radially outwardly from the hub.

Abstract: This invention includes drilling assemblies, drilling reamer arm assemblies, and methods of drilling. In one implementation, a drilling assembly includes a cutting head apparatus configured to cut into earthen material as the cutting head apparatus is rotated. A drive shaft extends aft of and is configured to rotate the cutting head apparatus. A plurality of reamer arm assemblies projects radially outward of the drive shaft and are mounted for rotation therewith aft of the cutting head apparatus. Individual of the reamer arm assemblies include a radial inner portion extending radially outward of the drive shaft. A radial outer portion connects with and extends radially outward of the radial inner portion. The radial outer portion includes a cutter. At least one breakaway retainer fastens the radial inner and outer portions together and restrains the radial outer portion from moving relative to the radial inner portion towards the cutting head apparatus and the drive shaft. Other aspects are contemplated.

Abstract: A cutter for a tunnel boring machine is equipped with a cutter body (1) with a slanting surface (2), a cylindrical contact surface (12) and a preferably tapered threaded portion with specially designed threads (6), a clamping ring (4) with threads adapted to the cutter body's threads with a slanting surface (5) with a groove (13) with a spring (14). The cutter has an undivided (3) or divided cutter ring (with segments 3a, 3b) with a cross section with slanting lateral surfaces (7, 8) in the foot and a cylindrical contact surface (11). The diameter of the cutter ring's cylindrical contact surface (11) has a clearance tolerance relative to the diameter of the cylindrical contact surface (12) of the cutter body.

Abstract: A rotary mine drilling bit for making blast holes having a connection at one end of the body for attachment to a drill string and the second end of the body having a plurality of longitudinally extending slots. A thrust shoulder is provided between the ends of the body and longitudinally extending supporting legs are positioned in each of the slots and are releasably connected to the body. One end of the supporting legs are positioned the adjacent the shoulders for receiving longitudinal thrust and for avoiding thrust on the connecting means. A roller bit is connected to the end of each supporting leg.

Abstract: A rotary cone drill bit is provided with enhanced fluid flow near the bottom of an associated borehole resulting in improved removal of cuttings and other debris from the bottom of the borehole. The drill bit includes a plurality of fluid passageways extending from the bit body to the exterior of the drill bit. The bit body may include an enlarged cavity with the fluid passageways extending therefrom. One end of the cavity preferably includes an opening to receive fluid from a drill string attached to the drill bit. The end of the cavity opposite from the opening may have a generally parabolic configuration. For one application, a web member extends from the lower portion of the bit body, occupying a void area between each cutter cone assembly. The web member preferably contains a plurality of fluid passageways which direct drilling fluid from the drill string, through the bit body, through the web member, and exiting at nozzles adjacent to the bottom of the associated borehole.

Abstract: A roller cone drill bit includes a bit body adapted to be rotated about a longitudinal axis. At least one leg depends from the bit body, and a journal is cantilevered from the leg. A roller cone is rotatably mounted on the journal. A cone retention member is disposed between a first slot in the journal and a corresponding second slot in the roller cone. An access hole runs through the journal to the first slot, penetrating the first slot at a location away from the top dead center of the first slot.

Abstract: A method of manufacturing a rolling cutter drill bit comprising a bit body which carries cutter assemblies each of which includes a cutter journal on the bit body, a cutter rotatably mounted on the journal, and a threaded retention ring screwed onto the cutter to retain the cutter on the journal while permitting a limited degree of axial displacement of the cutter relative to the journal. The method comprises the steps of predetermining a desired magnitude of maximum permitted axial displacement between the cutter and the journal, and then employing components for the cutter assembly which are so dimensioned as to provide, when assembled to form the cutter assembly, a maximum permitted axial displacement which is not greater than the predetermined magnitude. The appropriately dimensioned components may be specifically manufactured to the required size, or may be selected from a stock of components of differing sizes.

Abstract: A modular drill bit mounts legs within recesses in a body which are parallel to the central axis of the body using threaded studs with tapered outer portions, in conjunction with an attached pin having recesses therein receiving the upper ends of the legs. The lower ends of the legs terminate in spindles of open face configuration rotatably receiving cones thereon for rotation via a arrangement of bushings, roller bearings and thrust bearings, and a plurality of seals which slide and therefore rotate relative to both the leg spindle and the cone with the help of pressure compensating apparatus. A bushing disposed in the cone-leg spindle interface has oil-lubricated rubber rods disposed in apertures therein to prevent lock-up on an adjacent bearing surface. The cone is held in the leg spindle by a lock nut forming one end of a race for receiving rollers of a roller bearing, in conjunction with a ring-nut secured to an extended portion of the cone protecting the leg from wear and damage.

Abstract: A roller cutter (28) of a drill bit (10) is retained on a journal (24) for rotation by a retainer ring (82) having external screw threads (88) which are threaded onto mating screw threads (108) on the roller cutter (28) for rotation therewith. The retainer ring (82) is mounted within a semicircular groove (68) on the journal (24) and has an inner periphery formed of a smooth arcuate surface contacting the annular groove at a position spaced at least 10.degree. from the entrance opening of the groove thereby to reduce bending stresses exerted against the root (74) of the groove (68).

Abstract: An underreamer including a body having a bore therethrough, an arm mounted at its upper end to the body, a sleeve member detachably secured to the lower end of each arm and adapted to receive the frictional wear caused by the rotation of the conical cutter mounted thereto. Bearings and seals disposed between the cutter and the sleeve member provide smooth rotation of the cutter. In addition, locking pins and bearings extending between the arm and the sleeve member secure the sleeve on the arm. The arms are pivotally mounted in slots in the body and mechanical structure is provided for moving the arms to their cutting position with their lower ends positioned radially outward from the body.

Abstract: An earth boring bit having an improved two piece bearing construction using an internally tapered and threaded, cantilevered bearing lug extending obliquely inwardly and downwardly from a leg carried by the body of the bit. An internally tapered and threaded bearing sleeve is made up on the lug, and includes a mouth that engages a shoulder on a base region of the bearing lug. The mouth of the sleeve has a minimum radial thickness such that the sleeve may be made up to a selected minimum torque. The bearing sleeve has a length greater than that of the treaded portion to define a thick walled inner end region to receive a resilient retainer ring in a groove that provides a minimum section over the threads on the interior of the sleeve. The sleeve is boronized to achieve wear resistance in a manner that does not substantially reduce strength.