Abstract: A drill bit made according to one embodiment may include a bit body having a longitudinal axis, a plurality of gamma sensors placed in the bit body, at least two gamma ray sensors in the plurality of sensors are spaced-apart from each other along the longitudinal axis of the bit body, wherein each such sensor in the plurality of sensors is configured to detect gamma rays from the formation during drilling of the wellbore and to provide signals representative of the detected gamma rays, and a circuit configured to process at least partially the signals from each of the at least two gamma ray sensors for estimating an inclination of the bit body relative to the longitudinal axis.

Abstract: In one aspect, the present disclosure provides an apparatus for determining formation density. One embodiment of the apparatus includes a bottomhole assembly having a drill bit attached to end thereof for drilling through a formation, a first sensor in the drill bit configured to provide first signals for determining a first density of the formation proximate to the drill, a second sensor distal from the first sensor configured to provide signals for determining density of a second density of the formation, and a processor configured to determine the formation density from the first density and the second density.

Abstract: A method of forming an earth-boring tool includes introducing metal into a die, rotating the die to generate centrifugal forces on the metal, and cooling the metal in the rotating die. A rotary drill bit may include a unitary, centrifugally cast bit body including an integral shank, at least one blade, and at least one cutting element on the blade. A rotary drill bit or a roller cone may include a first centrifugally cast material and a second centrifugally cast material. Another rotary drill bit includes a bit body comprising a maraging steel alloy. A method of forming a rotary drill bit may include disposing cutting elements on a rotary drill bit comprising maraging steel and aging the rotary drill bit to form at least one intermetallic precipitate phase. Methods of repairing a rotary drill bit include annealing and aging at least a portion of a rotary drill bit.

Abstract: Methods of attaching cutting elements to earth-boring tools, comprising abutting a portion a cutting element against at least one surface of an earth-boring tool with a braze material disposed therebetween; and brazing the cutting element to the earth-boring tool by applying high-frequency vibrations to cause the braze material to become flowable. Methods of securing cutting elements to earth-boring tools may comprise at least partially coating a cutting element with a braze material. The cutting element may be at least partially disposed in a pocket formed in a body of an earth-boring tool with the braze material adjacent surfaces defining the pocket. The cutting element and the braze material may be ultrasonically torsionally oscillated to braze the cutting element within the pocket.

Abstract: A data acquisition module comprising a base sized and configured for disposition within a shank of a drill bit bore and an extension protruding therefrom having electrical contacts on an exterior surface thereof for connection to electrical contacts on an interior surface of a sub secured to the bit shank. A drill bit equipped with a data acquisition module, a bottom hole assembly including a drill bit bearing a data acquisition module operably coupled to a sub secured to the drill bit, and a method of transferring data from a data acquisition module carrying a data acquisition module to a sub secured to the drill bit.

Abstract: In one aspect, a method of making a drill bit is disclosed that includes selecting a drill bit configuration, obtaining a stress map for the drill bit configuration relating to a drilling operation, performing a mechanical test with an actual drill bit having the selected configuration, and selecting a location on a surface of the drill bit for installing a sensor thereat based on a location of low stress from the stress map and results of the mechanical test, and placing a sensor at the selected location.

Abstract: In one aspect, the present disclosure provides an apparatus for determining formation density. One embodiment of the apparatus includes a bottomhole assembly having a drill bit attached to end thereof for drilling through a formation, a first sensor in the drill bit configured to provide first signals for determining a first density of the formation proximate to the drill, a second sensor distal from the first sensor configured to provide signals for determining density of a second density of the formation, and a processor configured to determine the formation density from the first density and the second density.

Abstract: A cutting element for an earth-boring tool includes an elongated body having a longitudinal axis, a generally planar volume of hard material attached to the elongated body, and a sensor affixed to the elongated body. The sensor may be configured to sense at least one of stress and strain. An earth-boring tool includes a cutting element disposed at least partially within a pocket of a body. Methods of forming cutting elements comprise securing a generally planar volume of hard material to an elongated body, attaching a sensor to the elongated body, and configuring the sensor. Methods of forming earth-boring tools comprise forming a cutting element and securing the cutting element within a recess in a body of the earth-boring tool. Methods of forming wellbores comprise rotating an earth-boring tool comprising a cutting element and measuring at least one of stress and strain.

Abstract: The disclosure, in one aspect, provides a method of drilling a wellbore that includes features of drilling the wellbore using a drilling assembly that includes a drill bit that further includes a weight sensor and a torque sensor, determining weight-on-bit using measurements from the weight sensor and torque-on-bit using measurement from the torque sensor during drilling of the wellbore, obtaining measurements for rotational speed of the drill bit and rate of penetration of the drill bit during drilling of the wellbore, determining mechanical specific energy of the bottomhole assembly using the determined weight-on-bit, torque-on-bit and obtained rotational speed of the drill bit and the obtained rate of penetration of the drill bit, and altering a drilling a parameter in response to the determined mechanical specific energy.

Abstract: In one aspect, a method of determining a corrected weight-on-bit is provided, which method, in one embodiment, may include: drilling a wellbore with the drill bit; determining a weight-on-bit while drilling the wellbore; determining a pressure differential across an effective area of the drill bit while drilling the wellbore; and determining the corrected weight-on-bit from the determined weight-on-bit and the determined pressure differential.

Abstract: A drill bit made according to one embodiment includes at least one of a weight sensor and a torque sensor configured to provide signals representative of the weight and torque on the drill bit when the drill bit is used for cutting into a formation. A circuit may be configured to process signals from the weight and torque sensors to provide an estimate of the weight and torque on the bit when the drill bit is used for cutting into the formation.

Abstract: A rock bit is formed with pockets for enhanced cutting element retention and support of cutting elements during operation of the rock bit. Portions of the pockets are carburized to increase a yield strength of the pockets, which also increases the retention of the cutting elements. The pockets are formed at a diameter that is slightly smaller than an outer diameter of the cutting elements. Portions of the pockets are then carburized. The pockets are heated until the diameter of the pockets is equal to the outer diameter of the cutting elements. After the rock bit has been cooled and cleaned, a material is placed in each pocket prior to installing the cutting elements. The material homogenizes support for the cutting elements during operation of the rock bit.

Abstract: A drill bit having a bit body includes one or more acoustic sensors that are configured to detect elastic waves when the drill bit is used for drilling a wellbore. The acoustic sensor may be configured to detect a sonic signature associated with a failure event. In further arrangements, the acoustic sensors may be configured to receive signals from a controlled acoustic source.

Abstract: A drill bit made according to one embodiment includes at least a gamma ray sensor configured to provide signals representative of a presence and/or amount of a naturally occurring gamma ray source when the drill bit is used for cutting into a formation. A circuit may be configured to process signals from the gamma ray sensor to provide an estimate a parameter relating to the naturally occurring gamma ray source, which may used for purposes such as optimizing drilling parameters and geosteering.

Abstract: A drill bit made according to one embodiment includes a bit body and at least one preloaded sensor in the bit body. In one aspect, the sensor may include a sensor element on a sensor body having a first end and a second end and wherein the sensor is preloaded after placing the sensor body in the bit body. In another aspect, the sensor may be preloaded outside the bit body and then placed in the bit body in a manner that enables the sensor to retain the preloading.

Abstract: An apparatus made according to one embodiment includes a drill bit that has a cavity at an end thereof and a communication device placed in the cavity, wherein the communication device includes a first section and a second section, wherein an outer dimension of the second section is greater than an outer dimension of the first section, and wherein the second section includes a conduit configured to allow passage of a conductor from the drill bit to a location outside the drill bit so as to provide a direct connection of the conductor from the drill bit to an element outside the drill bit.

Abstract: A drill pipe made according to one embodiment includes a number of serially connected tubulars with a communication device placed between the connecting ends of the tubulars, wherein the communication device provides a direct data communication link between the adjoining tubulars.

Abstract: Drill bits and methods for sampling sensor data associated with a state of a drill bit are disclosed. A drill bit for drilling a subterranean formation comprises a bit configured for receiving a data analysis module. The data analysis module comprises at least one sensor, a memory, and a processor. The processor is configured for executing computer instructions to filter information derived from sensor data in the drill bit to develop a piecewise polynomial curve of the sensor data. Filtering information derived from the sensor data comprises approximating a first derivative of a sensor data waveform, calculating a plurality of zeros for the first derivative of the sensor data waveform, and fitting a cubic polynomial between adjacent zeros calculated from the first derivative of the sensor data waveform resulting in a piecewise cubic polynomial.

Abstract: Drill bits and methods of measuring drill bit conditions are disclosed. A drill bit for drilling a subterranean formation comprises a bit bearing at least one cutting element and adapted for coupling to a drill string. The drill bit may also comprise a chamber formed within the bit and configured for maintaining a pressure substantially near a surface atmospheric pressure while drilling the subterranean formation. In addition, the drill bit may comprise at least one optical sensor disposed in the chamber and configured for sensing at least one physical parameter exhibited by the drill bit while drilling a subterranean formation.

Abstract: In one aspect, an apparatus for use in a wellbore is provided that in one embodiment includes a drill bit having a bit body that is susceptible to corrosion when the drill bit is utilized in wellbore, an anode placed at a selected location on the bit body, a cathode associated with the bit body and a power source configured to provide electrical power to the anode to complete an electrical circuit between the anode and the bit body, wherein the supply of the electrical power to the anode arrests corrosion of the bit body when the drill bit is in the wellbore.