Abstract: A method for determining a rate of penetration of a drill bit during an earth drilling operation may comprise first urging an element to extend out from a working face of the drill bit. As drilling progresses, this extended element may then be forced back into the drill bit by an internal surface of a borehole being formed. A rate at which the element retracts back into the working face may be measured to aid in estimating a rate of penetration of the drill bit into the earth.

Abstract: A drilling apparatus may alter a direction of travel of a drill bit as it forms a borehole in the earth by furnishing the borehole with a cross-sectional shape that urges the drill bit in a radial direction. Such a cross-sectional shape may comprise two circular arcs, one larger than the apparatus and one smaller. The apparatus may be urged away from the smaller circular arc and into the open space provided by the larger circular arc. Such an apparatus may comprise an axial body and a cutting element extendable in a single radial direction from an exterior of the axial body. Extension of the cutting element may allow it to engage and degrade an inner wall of the borehole. An abrasion-resistant gauge pad protruding from the exterior of the body may ride against the borehole wall and urge the body radially.

Abstract: A method for determining a rate of penetration of a drill bit during an earth drilling operation may comprise first urging an element to extend out from a working face of the drill bit. As drilling progresses, this extended element may then be forced back into the drill bit by an internal surface of a borehole being formed. A rate at which the element retracts back into the working face may be measured to aid in estimating a rate of penetration of the drill bit into the earth.

Abstract: A drilling apparatus may alter a direction of travel of a drill bit as it forms a borehole in the earth by furnishing the borehole with a cross-sectional shape that urges the drill bit in a radial direction. Such a cross-sectional shape may comprise two circular arcs, one larger than the apparatus and one smaller. The apparatus may be urged away from the smaller circular arc and into the open space provided by the larger circular arc. Such an apparatus may comprise an axial body and a cutting element extendable in a single radial direction from an exterior of the axial body. Extension of the cutting element may allow it to engage and degrade an inner wall of the borehole. An abrasion-resistant gauge pad protruding from the exterior of the body may ride against the borehole wall and urge the body radially.

Abstract: Devices and methods for well logging using a wear-resistant electrode are provided. A downhole device may include a drill collar and a first electrode mounted on the drill collar. Further, the first electrode may include a wear-resistant face. The first electrode may be movably coupled within the drill collar, and the first electrode may be configured to extend and retract into a wellbore to maintain contact with a wall of the wellbore. Furthermore, the first electrode may be configured to measure impedance of a geological formation.

Abstract: Devices and methods for well logging using a wear resistant electrode are provided. A downhole device may include a drill bit, a gauge pad mounted on the drill bit, and a first electrode mounted in the gauge pad. An insulating polycrystalline diamond (PCD) material may surround at least a portion of the first electrode. Additionally, the first electrode may include an electrically conductive wear resistant contact point that maintains constant contact with a wall of a wellbore. Additionally, the first electrode may measure an impedance of a geological formation during a drilling operation.

Abstract: A linear measurement device may be formed from a first tube axially translatable with respect to a second tube. Inside the first tube may be placed a sensor capable of sensing a magnetic field. A magnet may also be found within the first tube and produce a magnetic field sensible by the sensor. The second tube may comprise a plurality of deviations disposed therealong capable of altering the magnetic field when near the magnet. As the first tube is axially translated with respect to the second tube, the sensor may sense alterations in the magnetic field due to the plurality of deviations thus allowing for a linear displacement to be determined.

Abstract: Devices and methods for well logging using a wear-resistant electrode are provided. A downhole device may include a drill collar and a first electrode mounted on the drill collar. Further, the first electrode may include a wear-resistant face. The first electrode may be movably coupled within the drill collar, and the first electrode may be configured to extend and retract into a wellbore to maintain contact with a wall of the wellbore. Furthermore, the first electrode may be configured to measure impedance of a geological formation.

Abstract: Devices and methods for well logging using a wear resistant electrode are provided. A downhole device may include a drill bit, a gauge pad mounted on the drill bit, and a first electrode mounted in the gauge pad. An insulating polycrystalline diamond (PCD) material may surround at least a portion of the first electrode. Additionally, the first electrode may include an electrically conductive wear resistant contact point that maintains constant contact with a wall of a wellbore. Additionally, the first electrode may measure an impedance of a geological formation during a drilling operation.