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.

Abstract: The present invention provides an earth boring drill bit with 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. This translates to higher wear resistance in cutting applications and has advantages in numerous other applications.

Abstract: The present invention provides 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.

Abstract: The present invention provides 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.

Abstract: Griffin, Nigel, et al78.1081-1.3-29 Disclosed is a method for manufacturing a polycrystalline diamond or diamond-like element with greatly improved wear resistance without loss of impact strength. These elements are formed with a binder-catalyzing material in a high-temperature, high-pressure (HTHP) process. The PCD element has a body with a plurality of bonded diamond or diamond-like crystals forming a continuous diamond matrix that has a diamond volume density greater than 85%. Interstices among the diamond crystals form a continuous interstitial matrix containing a catalyzing material. The diamond matrix table is formed and integrally bonded with a metallic substrate containing the catalyzing material during the HTHP process. The diamond matrix body has a working surface, 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.

Abstract: A rotary drill bit includes cutters arranged in a series of concentric rings, the cutters of one of the rings having a different wear resistance to the cutters of another of the rings with the result that the stability of the drill bit improves with wear. Although the wear resistance is different, the cutters have substantially the same impact toughness.

Abstract: A rotary valve assembly for a rotary steerable tool is disclosed for directing flow of an abrasive laden drilling fluid; the valve assembly has a first sealing surface rotatably engaging a second sealing surface. At least one of the surfaces has at least about 5% of its area comprising interconnecting voids to an average depth of at least 0.02 mm. The interconnected voids allow fluid pressure to equalize between the sealing faces by flowing through the interconnecting voids to the sealing surfaces. Because the fit of the sealing surfaces of the valve is less than perfect, and because the voids on mating surfaces do not necessarily overlap, the 5% of the surface area comprising interconnected voids can easily translate to a 10% or more reduction in sealed area when both sealing surfaces have the interconnecting voids. The additional reduction in surface area subjected to differential pressure has substantially eliminated the hydraulic lock problem previously encountered upon startup.

Abstract: A method for use in designing rotary drill bits comprises determining locations in which cutters are to be provided, determining likely wear rates for cutters positioned at those locations, and using the likely wear rates to chose between relatively high and relatively low wear rate cutters for each location. The cutters all have substantially the same impact toughness.

Abstract: A method of machining a polycrystalline diamond material including a matrix of interstices containing a catalyzing material and a volume close to a working surface thereof substantially free of catalyzing material which comprises the steps of treating the volume to render the polycrystalline diamond electrically conductive, and using an electron discharge machining technique to machine the polycrystalline diamond. In one embodiment, the treatment comprises applying a conductive material layer to a surface of the diamond.

Abstract: Disclosed is a polycrystalline diamond or diamond-like element with greatly improved wear resistance without loss of impact strength. These elements are formed with a binder-catalyzing material in a high-temperature, high-pressure (HTHP) process. The PCD element has a body with a plurality of bonded diamond or diamond-like crystals forming a continuous diamond matrix that has a diamond volume density greater than 85%. Interstices among the diamond crystals form a continuous interstitial matrix containing a catalyzing material. The diamond matrix table is formed and integrally bonded with a metallic substrate containing the catalyzing material during the HTHP process. The diamond matrix body has a working surface, where a first portion of the interstitial matrix in the body adjacent to the working surface is substantially free of the catalyzing material, and a second portion of the interstitial matrix in the body adjacent to the working surface contains the catalyzing material.

Abstract: Disclosed is a polycrystalline diamond or diamond-like element with greatly improved wear resistance without loss of impact strength. These elements are formed with a binder-catalyzing material in a high-temperature, high-pressure (HTHP) process. The PCD element has a body with a plurality of bonded diamond or diamond-like crystals forming a continuous diamond matrix that has a diamond volume density greater than 85%. Interstices among the diamond crystals form a continuous interstitial matrix containing a catalyzing material. The diamond matrix table is formed and integrally bonded with a metallic substrate containing the catalyzing material during the HTHP process. The diamond matrix body has a working surface, 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.

Abstract: A polycrystalline diamond material including a matrix of interstices containing a catalyzing material and a volume close to a working surface thereof substantially free of catalyzing material is treated to render the polycrystalline diamond electrically conductive. In one embodiment, the treatment comprises applying a conductive material layer to a surface of the diamond.

Abstract: The present invention provides 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.

Abstract: Disclosed is a polycrystalline diamond or diamond-like element with greatly improved wear resistance without loss of impact strength. These elements are formed with a binder-catalyzing material in a high-temperature, high-pressure (HTHP) process. The PCD element has a body with a plurality of bonded diamond or diamond-like crystals forming a continuous diamond matrix that has a diamond volume density greater than 85%. Interstices among the diamond crystals form a continuous interstitial matrix containing a catalyzing material. The diamond matrix table is formed and integrally bonded with a metallic substrate containing the catalyzing material during the HTHP process. The diamond matrix body has a working surface, 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.

Abstract: A rotary drill bit includes cutters arranged in a series of concentric rings, the cutters of one of the rings having a different wear resistance to the cutters of another of the rings with the result that the stability of the drill bit improves with wear. Although the wear resistance is different, the cutters have substantially the same impact toughness.

Abstract: A method for use in designing rotary drill bits comprises determining locations in which cutters are to be provided, determining likely wear rates for cutters positioned at those locations, and using the likely wear rates to chose between relatively high and relatively low wear rate cutters for each location. The cutters all have substantially the same impact toughness.