Abstract: A cutter is configured with a diamond table made from a thin hard facing material layer of polycrystalline diamond bonded to a backing layer made from cemented tungsten carbide. The face of the diamond table includes a concavity formed with a curved shape wherein at least a portion of the face in a center of the cutter is recessed with respect to at least some portion of the face about the perimeter of the cutter. This concave curved shape is formed in the diamond table itself such that the diamond table has a varying thickness depending on the implemented concavity. Alternatively, the concave curved shape is formed in the backing layer and a substantially constant thickness diamond table layer is attached thereto.

Abstract: A process is presented which produces at least one block of dense material constituted by hard particles dispersed in a binder phase, it being possible for the dense material to be enriched locally with binder phase by imbibition. The process includes bringing at least one imbibition area of a surface of the block, preferably coated with a coating material, into contact with an imbibiting material which locally enriches the block with binder phase. The block in contact with the imbibiting material is then subjected to a suitable thermal cycle constituted by heating, temperature maintenance and cooling. This serves to bring some or all of the imbibiting material and the binder phase of the block into the liquid state in such a manner that the enrichment with binder phase takes place solely through the imbibition area. The block is used in connection with the building of a drill bit or tool.

Abstract: A PDC cutter utilizes the combination of an elliptical shape with higher thermal resistance obtained through leaching to provide a cutter which is more effective than a cutter using either concept alone. The PDC cutter includes a tungsten carbide portion with protrusions extending from a surface thereof in a pattern. The diamond volume is mounted to the surface wherein the protrusions allow for the diamond volume to be larger about a perimeter edge of the cutter and smaller/shallower in a center region of the cutter. The protrusions providing surfaces for the diamond layer (table) to bond to the underlying tungsten carbide portion. With this configuration, diamond volume is maximized around the edge of the cutter.

Abstract: A drag-type drill bit for bore hole drilling in earth formation comprises a bit body having a threaded pin on one end for coupling to a drill string. A substantially dome-shaped cutter head is formed integral with the bit body opposite from the threaded pin. Formed integral with and extending from the cutter head is a plurality of circumferentially spaced fixed and/or variable pitch spiral blades having a succession of curved segments. The variable pitch pattern curves from substantially the center of and around the cutter head to the gage area. A plurality of generally cylindrical cutting elements, such as PDC elements, are fixed to each of the spiral blades and a plurality of nozzles are positioned around the cutter head to direct drilling fluid passing through the bit body against the blades to the annulus surrounding the bit body and the bore hole.

Abstract: A method for creating a rapid prototype mold for parts of an earth boring tool for manufacture thereof comprises initially optimizing the drill bit design and integrating this design into CAD code. The CAD code is utilized to generate a prototype file in a computer outputting command signals to a laser, and a laser scanner to prototype a mold utilizing stereolithography, selective laser sintering, or laminated object manufacturing, in addition to other prototype techniques to manufacture earth boring tool parts.

Abstract: A cutting element for an earth boring bit comprises a cutting compact of a superabrasive material layer bonded to a supporting substrate. The superabrasive material layer has a pattern of radially extending ribs, the ribs extending from the peripheral surface of the layer, and a second pattern of circular ribs radially spaced from the peripheral surface and intersecting the first pattern of radially extending ribs. The supporting substrate comprises a first pattern of radially extending grooves for mating with the first pattern of radially extending ribs. In addition, the supporting substrate comprises a second pattern of circular grooves for mating with the first pattern of circular ribs. The interface between the substrate and the superabrasive material has a dome-shaped configuration.