Abstract: A bit mold is milled using a turning stage which forms a base mold component and a base gagering component. Next, a blade milling stage is performed in which the base mold component and base gagering component are milled to define integral junkslot formers separated by blade regions. Lastly, a pocket milling stage is performed in which the blade regions and integral junkslot formers of the base mold component are milled to define a plurality of cutter pockets in primary and perhaps secondary rows. Each cutter pocket includes a seat portion and a face portion. The milling of the pocket milling stage provides, at one or more of the cutter pockets, a facet. This facet is provided in an area about the junkslot former associated with the face portion of the cutter pocket, the face portion having, due to the presence of the facet, a surface for matching a cutter core displacement end surface without voids of a size which would require the use of fill material.

Abstract: An apparatus that includes one or more flow channels and method for fabricating such flow channels. The apparatus includes a body and one or more blades extending from one end of the body. Each blade includes a leading section, a trailing section, a face section extending from one end of the leading section to an end of the trailing section, and at least one flow channel extending from the leading edge section to the trailing edge section.

Abstract: A PDC bit includes a plurality of blades including primary blades and secondary blades. The included primary blades are set with PDC cutters in accordance with a “single set” methodology. The included secondary blades, however, are set with PDC cutters using a type of “plural set” methodology such that the radial positions of cutters on a secondary blade match the radial positions of cutters on a single set primary which is immediately preceding that secondary blade. Plural secondary blades can be positioned to follow a single primary blade, and the cutters on those plural secondary blades will have radial positions matching the cutters of the immediately preceding single set primary blade.

Abstract: A PDC bit includes a plurality of blades including primary blades and secondary blades. The included primary blades are set with PDC cutters in accordance with a “single set” methodology. The included secondary blades, however, are set with PDC cutters using a type of “plural set” methodology such that the radial positions of cutters on a secondary blade match the radial positions of cutters on a single set primary which is immediately preceding that secondary blade. Plural secondary blades can be positioned to follow a single primary blade, and the cutters on those plural secondary blades will have radial positions matching the cutters of the immediately preceding single set primary blade.

Abstract: A bit mold is milled using a turning stage which forms a base mold component and a base gagering component. Next, a blade milling stage is performed in which the base mold component and base gagering component are milled to define integral junkslot formers separated by blade regions. Lastly, a pocket milling stage is performed in which the blade regions and integral junkslot formers of the base mold component are milled to define a plurality of cutter pockets in primary and perhaps secondary rows. Each cutter pocket includes a seat portion and a face portion. The milling of the pocket milling stage provides, at one or more of the cutter pockets, a facet. This facet is provided in an area about the junkslot former associated with the face portion of the cutter pocket, the face portion having, due to the presence of the facet, a surface for matching a cutter core displacement end surface without voids of a size which would require the use of fill material.

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: An earth boring bit having a body, pressure compensating lubricating system and cantilevered bearing shaft with an annular seal surface and a radial seal surface. A cutter is rotatably secured to the bearing shaft, with an annular seal recess having radial and cylindrical seal surfaces to oppose the seal surfaces on the body and bearing shaft to define a seal gland. A resilient and annular packing ring is compressed between the cylindrical seal surfaces, but has a length less than the minimum length of the gland. A shroud extends inwardly near the outer backface a selected distance behind the packing ring to bias it inwardly. The shroud extends inwardly toward the bearing not more than about 30% of the cross-sectional thickness of the O-ring in the relaxed condition. The O-ring is compressed in a range of about 10 to 15 percent.