Abstract: An apparatus for measuring a resistivity of a formation comprising an instrumented bit assembly coupled to a bottom end of the apparatus. At least one first electromagnetic wave antenna transmits an electromagnetic wave signal into the formation. At least one second electromagnetic wave antenna located on the instrumented bit assembly and longitudinally spaced apart from the at least one first electromagnetic wave antenna receives the electromagnetic wave signal transmitted through the formation. Electronic circuitry is operably coupled to the at least one second electromagnetic wave antenna to process the received signal to determine a resistivity of the formation proximate the instrumented bit assembly.

Abstract: A formation core analysis system can include an inner barrel and a toroidal electromagnetic antenna which transmits electromagnetic signals into a formation core when the core is received in the inner barrel. Another formation core analysis system can include an inner barrel and multiple longitudinally spaced apart electrodes which electrically contact a formation core when the core is received in the inner barrel. A speed of displacement of the core into the inner barrel may be indicated by differences between measurements taken via the electrodes as the core displaces into the inner barrel. A method of measuring resistivity of a formation core as the core is being cut can include transmitting electromagnetic signals into the core from a toroidal electromagnetic antenna as the core is being cut by a coring bit.

Abstract: One method of monitoring a formation core during coring operations can include measuring resistivities of a formation internal and external to a core barrel assembly, comparing the resistivities of the formation internal and external to the core barrel assembly, and determining a displacement of the core into the core barrel assembly, based at least in part on the comparing, while the core is being cut. A formation core analysis system can include multiple longitudinally spaced apart sets of transmitters and receivers which measure resistivity of a core while the core displaces into a core barrel assembly, and multiple longitudinally spaced apart sets of transmitters and receivers which measure resistivity of a formation external to the core barrel assembly while a coring bit penetrates the formation. A speed of displacement of the core may be indicated by differences in time between measurements taken via the different sets as the core displaces.

Abstract: A disclosed method for obtaining a core sample includes directing light at a core sample being collected, receiving reflected light from the core sample, and analyzing the received reflected light to determine one or more characteristics of the core sample and/or form an image of the core sample. Characteristics include rock type, hydrocarbon type, water concentration, porosity, and permeability. The light may be infrared (IR), visible, and/or ultraviolet (UV). The received reflected light may be passed through one or more multivariate optical elements (MOEs). Measurements made at two different positions on the core sample may be used to determine a coring rate. A described coring bit includes a barrel to receive a core sample, a light source illuminating the core sample as it enters the barrel, a detector system that receives reflected light from the core sample, and an optical transmission system communicating light to and from the core sample.

Abstract: The disclosure provides a super-abrasive body including a thermally stable polycrystalline diamond (TSP) body having a top region and an enhanced attachment region, wherein the enhanced attachment region includes tungsten carbide particles having a volume of at least 30% of the total volume of the enhanced attachment region. The disclosure further provides a super-abrasive element having the super-abrasive body attached to a substrate via an attachment material located in or around the tungsten carbide particles. The disclosure additionally provides earth-boring drill bits with such a super-abrasive element. Further, the disclosure provides methods of forming such super-abrasive bodies and elements by forming a PCD body with particle of tungsten carbide in an enhanced attachment region, then leaching the PCD body and attaching it to a substrate via an attachment material in or around the tungsten carbide particles.

Abstract: The disclosure provides a PCD element containing a substrate and a PCD layer. The PCD has a top surface, a side surface, an intermediate surface, an unleached region containing a diamond body matrix and an interstitial matrix including a catalyst, and a leached region containing a diamond body matrix and empty space in the place of the interstitial matrix. The catalyst has been leached from the empty space in the place of the interstitial matrix. The unleached region is adjacent to a substantial portion of the side surface and the leached region is not adjacent to a substantial portion of the side surface, and the leached region is adjacent to the top surface or the intermediate surface. The disclosure also provides a system and method for leaching a PCD element including a liquid able to leach a catalyst and a protective member.

Abstract: A method of reducing contact pressure between bearing surfaces of a well tool can include constructing a structure which supports one bearing surface in contact with the other bearing surface, and reducing contact pressure between the bearing surfaces by relieving strain energy in the structure. A well tool can include one bearing surface which contacts another bearing surface. There is a transition between contact and lack of contact between the bearing surfaces. A structure supporting one of the bearing surfaces can have a reduced stiffness, whereby a contact pressure between the bearing surfaces is reduced at the transition. The bearing surfaces can be formed on a thrust bearing, plain bearing, or other type of bearing between components of the well tool.

Abstract: The disclosure provides to a PDC element protective system including a mask configured to protect a non-leached portion of a leached polycrystalline diamond compact (PDC) element during a leaching process. The mask may be formed from or coated with polytetrafluoroethylene (PTFE). The disclosure also provides a leaching system containing such a mask and a leaching vessel as well as methods of using the protective and leaching systems. The disclosure further provides a Lewis acid-based leaching agent and methods of its use. Finally, the disclosure provides a method of recycling a PDC or carbide element using a Lewis acid-based leaching agent.

Abstract: The present disclosure provides mechanical attachments of TSD body to a carrier or substrate sufficient to allow eventual conventional attachment of the TSD to a drill bit or other component. According to one aspect, the disclosure includes a composite assembly including a thermally stable diamond (TSD) body and a substrate with aligned holes and a joining pin located in the aligned holes to mechanically attach the TSD body and substrate. The composite assembly may lack any non-mechanical attachment between the TSD body and the substrate, or may lack particular types of non-mechanical attachments. The disclosure also provides drill bits and other devices containing such composite assemblies as well as methods of making such composite assemblies and drill bits or other devices.

Abstract: The disclosure provides to a PDC element protective system including a mask configured to protect a non-leached portion of a leached polycrystalline diamond compact (PDC) element during a leaching process. The mask may be formed from or coated with polytetrafluoroethylene (PTFE). The disclosure also provides a leaching system containing such a mask and a leaching vessel as well as methods of using the protective and leaching systems. The disclosure further provides a Lewis acid-based leaching agent and methods of its use. Finally, the disclosure provides a method of recycling a PDC or carbide element using a Lewis acid-based leaching agent.

Abstract: An apparatus for measuring a resistivity of a formation comprising an instrumented bit assembly coupled to a bottom end of the apparatus. At least one first electromagnetic wave antenna transmits an electromagnetic wave signal into the formation. At least one second electromagnetic wave antenna located on the instrumented bit assembly and longitudinally spaced apart from the at least one first electromagnetic wave antenna receives the electromagnetic wave signal transmitted through the formation. Electronic circuitry is operably coupled to the at least one second electromagnetic wave antenna to process the received signal to determine a resistivity of the formation proximate the instrumented bit assembly.

Abstract: A method of reducing contact pressure between bearing surfaces of a drill bit can include constructing a structure which supports one bearing surface in contact with the other bearing surface, and reducing contact pressure between the bearing surfaces by relieving strain energy in the structure. A drill bit can include one bearing surface which contacts another bearing surface. There is a transition between contact and lack of contact between the bearing surfaces. A structure supporting one of the bearing surfaces has a reduced stiffness, whereby a contact pressure between the bearing surfaces is reduced at the transition.

Abstract: A method of reducing contact pressure between bearing surfaces of a well tool can include constructing a structure which supports one bearing surface in contact with the other bearing surface, and reducing contact pressure between the bearing surfaces by relieving strain energy in the structure. A well tool can include one bearing surface which contacts another bearing surface. There is a transition between contact and lack of contact between the bearing surfaces. A structure supporting one of the bearing surfaces can have a reduced stiffness, whereby a contact pressure between the bearing surfaces is reduced at the transition. The bearing surfaces can be formed on a thrust bearing, plain bearing, or other type of bearing between components of the well tool.

Abstract: A method and apparatus for predicting the performance of a drilling system for the drilling of a well bore in a given formation includes generating a geology characteristic of the formation per unit depth according to a prescribed geology model, obtaining specifications of proposed drilling equipment for use in the drilling of the well bore, and predicting a drilling mechanics in response to the specifications as a function of the geology characteristic per unit depth according to a prescribed drilling mechanics model. Responsive to a predicted drilling mechanics, a controller controls a parameter in the drilling of the well bore. The geology characteristic includes at least rock strength. The specifications include at least a bit specification of a recommended drill bit. Lastly, the predicted drilling mechanics include at least one of bit wear, mechanical efficiency, power, and operating parameters.

Abstract: A method and apparatus for predicting the performance of a drilling system for the drilling of a well bore in a given formation is disclosed. The method generates a geology model of a given formation. The geology model includes a geology characteristic of the given formation per unit depth. The method also determines a predicted drilling performance for a proposed drilling equipment based on the geology model and specification data of the proposed drilling equipment, wherein the specification data of the proposed drilling equipment is a function of the geology characteristic.

Abstract: A method and apparatus for predicting the performance of a drilling system for the drilling of a well bore in a given formation includes generating a geology characteristic of the formation per unit depth according to a prescribed geology model, obtaining specifications of proposed drilling equipment for use in the drilling of the well bore, and predicting a drilling mechanics in response to the specifications as a function of the geology characteristic per unit depth according to a prescribed drilling mechanics model. Responsive to a predicted-drilling mechanics, a controller controls a parameter in the drilling of the well bore. The geology characteristic includes at least rock strength. The specifications include at least a bit specification of a recommended drill bit. Lastly, the predicted drilling mechanics include at least one of bit wear, mechanical efficiency, power, and operating parameters.

Abstract: A method and apparatus for predicting the performance of a drilling system for the drilling of a well bore in a given formation is disclosed. The method generates a geology model of a given formation. The geology model includes a geology characteristic of the given formation per unit depth. The method also determines a predicted drilling performance for a proposed drilling equipment based on the geology model and specification data of the proposed drilling equipment, wherein the specification data of the proposed drilling equipment is a function of the geology characteristic.

Abstract: A method and apparatus for predicting the performance of a drilling system for the drilling of a well bore in a given formation includes generating a geology characteristic of the formation per unit depth according to a prescribed geology model, obtaining specifications of proposed drilling equipment for use in the drilling of the well bore, and predicting a drilling mechanics in response to the specifications as a function of the geology characteristic per unit depth according to a prescribed drilling mechanics model. Responsive to a predicted-drilling mechanics, a controller controls a parameter in the drilling of the well bore. The geology characteristic includes at least rock strength. The specifications include at least a bit specification of a recommended drill bit. Lastly, the predicted drilling mechanics include at least one of bit wear, mechanical efficiency, power, and operating parameters.

Abstract: A method and apparatus for predicting the performance of a drilling system for the drilling of a well bore in a given formation includes generating a geology characteristic of the formation per unit depth according to a prescribed geology model, obtaining specifications of proposed drilling equipment for use in the drilling of the well bore, and predicting a drilling mechanics in response to the specifications as a function of the geology characteristic per unit depth according to a prescribed drilling mechanics model. Responsive to a predicted drilling mechanics, a controller controls a parameter in the drilling of the well bore. The geology characteristic includes at least rock strength. The specifications include at least a bit specification of a recommended drill bit. Lastly, the predicted drilling mechanics include at least one of bit wear, mechanical efficiency, power, and operating parameters.

Abstract: A method and apparatus for predicting the performance of a drilling system for the drilling of a well bore in a given formation includes generating a geology characteristic of the formation per unit depth according to a prescribed geology model, obtaining specifications of proposed drilling equipment for use in the drilling of the well bore, and predicting a drilling mechanics in response to the specifications as a function of the geology characteristic per unit depth according to a prescribed drilling mechanics model. The geology characteristic includes at least rock strength. The specifications includes at least a bit specification of a recommended drill bit. Lastly, the predicted drilling mechanics include at least one of bit wear, mechanical efficiency, power, and operating parameters. A display is provided for generating a display of the geology characteristic and predicted drilling mechanics per unit depth, including either a display monitor or a printer.