Abstract: A high pressure/high temperature process is disclosed for making polycrystalline diamond or CBN compacts having chip control surfaces formed thereon. Making these chip control surfaces is accomplished by pre-forming the indentations or raised dimples within the can used in the HP/HT process.

Abstract: A steel bodied PCD drag bit is disclosed having a plurality of blades integrally formed thereon, each blade having a bottom surface that includes an angular front section and rear section intersecting to form an apex, the front section having a plurality of sockets formed thereon to receive a plurality of cylindrical cutters elements, the rear section being substantially parallel to the cylindrical cutting.

Abstract: A nozzle retention receptacle for rotary cone rock bits consists of a nozzle retention receptacle body forming a fluid passage therethrough. The body forms a first upstream entrance end that forms part of a wall of a plenum formed within a rock bit body and a second downstream exit end. The upstream end further forms a mounting interface that circumvents a fluid entrance port to the passage in the nozzle retention receptacle. The port communicates with the fluid plenum in the bit body. The body of the rock bit further forms a nozzle retention receptacle mounting interface that is common to the mounting interface formed by the nozzle retention receptacle.

Abstract: A two trip sidetrack casing milling apparatus for elongating and enlarging a previously formed window in a cased borehole in preparation for a subsequent sidetracking drilling operation is disclosed. The apparatus consists of three mills on a shaft, a first window mill is secured to an end of a shaft. The first window mill forms a diameter larger than a diameter of a subsequent sidetracking drill bit that is passed through the window. A second pilot mill is secured to the shaft and strategically positioned above the first window mill. The second pilot mill forms a diameter that is less than the diameter of the first window mill. A third watermelon mill is secured to the shaft and strategically positioned above the second pilot mill. The third watermelon mill forms a diameter that is at least the same diameter as the first window mill.

Abstract: A radially disposed thrust bearing assembly for air cooled and lubricated mining type rotary cone rock bits consists of a first non-rotating radially disposed steel thrust bearing disc and an apposed, non-rotating carbide thrust bearing disc. One of the thrust bearing discs is pressed into a disc retention socket formed in the end of a spindle bearing extending from the end of a main axially aligned bearing cantilevered from a leg of the bit and the other thrust bearing disc is pressed into a disc retention socket formed in the rotary cone. An edge of the carbide disc is formed with large valleys and peaks, the robust undulations resist cracking when the carbide thrust bearing disc is pressed into its respective socket. Unique air passages and channels are formed in the main and spindle bearings to direct cooling air to the apposed thrust bearing discs.

Abstract: A retrievable whipstock which can be hydraulically set within a wellbore and following the drilling procedure mechanically released and retrieved for future use. The whipstock includes a whip which directs a milling tool from the main well and a hydraulically actuated packer or anchor for setting the whipstock in the wellbore. The retrieval tool includes a nose piece to ensure proper orientation relative to the whipstock and a die collar to threadably engage the whip. An adapter on the retrieval tool wedges the whip away from the casing wall to ensure mating engagement between the retrieval tool and the whip. The whipstock is released through the application of tension through the retrieval tool allowing removal from the wellbore.

Abstract: A chisel type insert is disclosed having a contoured surface in which the vertical lines located on the surface are bowed outwardly in a convex manner thereby eliminating blend radii from the cutting tip and the high stress concentrations associated therewith.

Abstract: A conical insert is disclosed having a cutting tip which includes a spherically shaped apex and a substantially conical surface therebelow. The trailing side of the cutting tip is convex as seen in the longitudinal section taken normal to the apex. The leading side of the cutting tip is either a straight line segment or is concave as seen in the longitudinal section taken normal to the apex.

Abstract: A rock bit is disclosed having a plurality of rolling cone cutters each having a gage row of inserts oriented to face the borehole bottom for crushing the same, and a second row of heel gage inserts which are oriented to face the borehole sidewall for scraping the same, heel inserts are nestled within the profile of the gage inserts in order to alleviate most of the scraping action normally encountered by gage inserts.

Abstract: A tungsten carbide chisel insert for rock bits is disclosed having a cylindrical base section and a cutting tip section, the top of the tip section having an elongated crest, the remainder of the cutting tip section below the crest is a contoured surface formed having cross-sections being shaped as to provide for better overall performance.

Abstract: A chisel insert for rolling cone rock bits is disclosed in which the crest of the insert has a "dog bone" shape by being rounded with the crest ends flaring out to a larger dimension than the middle thereof. The crest is also convex upwardly along its median line thereby making a shorter moment arm at the ends of the crest.

Abstract: A chisel gage insert is disclosed having a larger nose radius at the outer end of the insert crest than at the inner end thereby providing more mass on the portion of the insert that contacts the borehole sidewall. The rounded crest also blends with the convex surfaces of the insert extension so as not to have any non-tangential intersections.

Abstract: A remedial bottom hole assembly for casing retrieval is disclosed having a spear and an inflatable packer utilized in combination with a pipe cutter. With such an assembly, after the spear is set and the casing is cut, the packer can be inflated to determine if circulation can be established without the removal of the spear and pipe cutter.

Abstract: A retention system is disclosed for a hammer-percussion bit assembly which prevents the loss of the lower section of bit after a crack propagates through the shank (rotational drive) section of the bit. The system includes retainer which is mounted onto the drive sub of the assembly. The retainer is adapted to extend around the head section of the bit and functions to grab the severed bit head section upon lifting of the drill string while not interfering with the normal operation of the assembly.

Abstract: A bottom hole assembly is described having a bit driven by a downhole motor and stabilizers located above the motor on the drill string. A subassembly is also provided for controlling the bit trajectory that is operational on demand at the rig site. The subassembly comprises an underreamer located directly above the bit. The underreamer is hydraulically actuated to retract and extend the cutters.

Abstract: A bearing assembly for a downhole motor comprising a pair of annular support rings, each having a plurality of polycrystalline diamond thrust bearing inserts mounted thereon. The rings are oriented to have the respective inserts face and bear against each other. In operation, drilling mud passes through the space between the inserts to cool the inserts. The rings are made of tungsten carbide to prevent erosion of the areas at the bases of the inserts, thereby improving the life of the thrust bearings.

Abstract: A composite material is disclosed along with the method of making the same. The material comprises a tough grade of cemented carbide granule dispersed with a hard brittle grade of cemented carbide granules to form a matrix. The quantity of hard, brittle cemented carbide granules is between 20% to 60% of the total composition. Such material functions to improve wear resistance without sacrificing toughness.

Abstract: A bottom hole assembly is disclosed consisting of a downhole motor having a drill bit connected to its lower end and a bent sub attached to its upper end. The downhole motor includes a motor housing, a connecting rod housing and a bearing housing. The connecting rod housing has a bend angle formed on the housing, which is enlarged to enable the connecting rod to be titled at a larger angle than otherwise possible. The enlarged connecting rod housing also functions as a near bit stabilizer.

Abstract: A new and improved tungsten carbide insert for rock bits is disclosed, in which the inserts are subject to extended vibratory tumbling in order to increase their fracture toughness. More specifically the vibratory finishing or tumbling of the inserts has been increased from a typical time of 30-60 minutes to time periods of at least 90 minutes and preferably a minimum of 225 minutes. A marked improvement in toughness is obtained by this process because the size and distribution of surface flaws of the inserts were greatly reduced, and because the surface hardness of the inserts was increased, thereby resulting in an increase in the stress required to cause fracture, and a consequent increase in resistance to breakage.

Abstract: A drill string sub is disclosed for measuring the torque and axial compression in the drill string. The drill string sub includes an outer tubular housing and an inner sleeve type apparatus mounted thereto for amplifying the strain the sensors measure. The sub further includes a section for compensating for the axial stresses due to the local pressure differential between the drill string bore and the well bore annulus and for the thermal gradients occurring during operation. This section includes a balance tube for isolating the internal bore pressure from acting on the strain amplifier and for creating an upward axial force on the tubular housing and strain amplifier which is responsive to this pressure differential to counter the axial stresses mentioned above. The sensors are encapsulated in oil to avoid the effects of the corrosion and electrical shorting which are promoted by drilling fluids.