Abstract: A PCD cutting element for use in earth boring drill bits where die interstices remote from the working surface are filled with a catalyzing material and the interstices adjacent to the working surface are substantially free of the catalyzing material is described. An intermediate region between the substantially free portion and filled portion has a plurality of generally conically sectioned catalyst-free projections which taper down, extending to a second depth from the planar working surface, preferably about 0.5 times or more of the first depth.

Abstract: A polycrystalline diamond cutting element for earth boring drill bits presents regions of different abrasion resistance to the earthen formation when in operation. The cutting element has an end working surface and a region which is substantially free of catalyzing material, forming a layer. In operation, this layer wears at a different rate than the underlying material causing a pair of protruding lips to form. The end working surface may be substantially planar or frusto-conical in form.

Abstract: Disclosed is a method of comparing the relative lateral stability among drill bits (that is, the tendency for a bit to whirl). This allows improved bit selection in applications where whirl is apparent. Because there will likely be many different acceptable bit designs produced by the above method, the comparison of the regenerative forces among these bits allows a customer to make a more informed choice between stability and other performance features among a range of bit designs.

Abstract: A stabilizer comprises a body having first and second ends, each of which is formed with a respective connector means, the body having an outer wall upon which is formed a plurality of the upstanding blades radially outer surfaces of which define gauge pads, flow channels being defined between adjacent ones of the blades, and at least one bridging region interconnecting two adjacent ones of the blades to form an enclosed passage communicating with an associated one of the flow channels, the bridging region having a surface defining part of an outer gauge surface of the stabilizer, the at least one bridging region being located intermediate and spaced from the first and second ends.

Abstract: The present invention provides a method of making an earth boring drill bit having a superhard polycrystalline diamond or diamond-like element with greatly improved resistance to thermal degradation without loss of impact strength. Collectively called PCD elements, these elements are formed with a binder-catalyzing material in a high-temperature, high-pressure process. The PCD element has a plurality of partially bonded diamond or diamond-like crystals forming at least one continuous diamond matrix, and the interstices among the diamond crystals forming at least one continuous interstitial matrix containing a catalyzing material. The element has a working surface and a body, where a portion of the interstitial matrix in the body adjacent to the working surface is substantially free of the catalyzing material, and the remaining interstitial matrix contains the catalyzing material.