Abstract: A wireline apparatus for deep well measurements in a borehole being drilled includes a drill string having multiple drill pipe sections connected end-to-end, with at least one of the drill pipe sections being electrically conductive and isolated to provide an electrode section. A nonmagnetic drill pipe section is connected in the drill string below said electrode section, and a hydraulic motor having a rotatable drill bit carrying a drill bit instrument sub having a magnetic field sensing instrument package is connected to a lowermost end of the drill string. A wireline locatable within said drill string incorporates an electrode locatable within the drill pipe electrode section, and carries at its distal end a wireline instrument package that is locatable within the nonmagnetic drill pipe section to receive data representing magnetic field data from the magnetic field sensing instrument package.

Abstract: An electromagnetic method and apparatus for determining the azimuthal orientation of a drill bit instrumentation sub (70), with respect to a borehole bottom drilling assembly (150) includes an electromagnet (152) fastened to the drilling assembly to produce an auxiliary alternating electromagnetic field (162) having an axis (163) that is perpendicular to the borehole axis (160). The direction of the field lines (162) generated by this magnet (152) and the simultaneous measurement of an electromagnetic field (36) generated by current flow in a blowout well casing is measured by electromagnetic field sensors in the drill bit instrument sub (70) to determine the direction to a blowout The direction of the auxiliary field (162) produced by the electromagnet (152) makes it possible to determine the direction to the blowout with reference to the direction of drilling without using an intermediate parameter such as, for example, the direction of gravity.

Abstract: A method and apparatus for tracking the drilling progress of a borehole such as a horizontal borehole that is drilled under an obstacle along a prescribed path is based upon triangulation from two laterally separated loops of wire lying on the ground, which generate corresponding alternating magnetic fields.

Abstract: A method and apparatus for magnetic field measurements to determine the proximity of a nearby target incorporating electrically conductive material includes a drill string (54) having multiple drill pipe sections (56, 57, 58, 59) connected end-to-end, with at least one of the drill pipe sections (57) being electrically conductive and isolated to provide an electrode section. A nonmagnetic drill pipe section (84) is connected in the drill string below the electrode section (57), and a hydraulic motor (62) having a rotatable drill bit sub (70) carrying a magnetic field sensing instrument package (102) is connected to a lowermost end of the drill string.

Abstract: A wireline apparatus for deep well measurements in a borehole being drilled includes a drill string having multiple drill pipe sections connected end-to-end, with at least one of the drill pipe sections being electrically conductive and isolated to provide an electrode section. A nonmagnetic drill pipe section is connected in the drill string below said electrode section, and a hydraulic motor having a rotatable drill bit carrying a drill bit instrument sub having a magnetic field sensing instrument package is connected to a lowermost end of the drill string. A wireline locatable within said drill string incorporates an electrode locatable within the drill pipe electrode section, and carries at its distal end a wireline instrument package that is locatable within the nonmagnetic drill pipe section to receive data representing magnetic field data from the magnetic field sensing instrument package.

Abstract: A downhole source of electrical power for drilling tools is driven by the rotation of a drillstring or, if the drillstring is not rotating, by the rotation of a drilling sub. The source consists of an alternator having a rotor made up of a series of coils that are mounted on, and spaced around the circumference of, a rotating drilling sub, and a stator made up of a multiplicity of permanent magnets also spaced around the circumference of the drilling sub. The stator is mounted on the drilling sub by means of bearings and incorporates a counterweight that holds the rotor relatively stationary with respect to the sub and with respect to the coils, so that rotation of the sub, either by rotation of the drillstring or by rotation of a drill motor in the drilling sub, produces relative rotation of the rotor and stator to generate an AC electrical output.

Abstract: Electrically powered electromagnetic field source beacons installed in a reference well in combination with a down-hole measurement while drilling (MWD) electronic survey instrument near the drill bit in the borehole being drilled permit distance and direction measurements for drilling guidance. Each magnetic field source beacon consists of a coil of wire wound on a steel coupling between two lengths of steel tubing in the reference well, and powered by an electronic package. Control circuitry in the electronic package continuously “listens” for, and recognizes, a “start” signal that is initiated by the driller. After a “start” signal has been received, the beacon is energized for a short time interval during which an electromagnetic field is generated, which is measured by the MWD apparatus.

Abstract: A downhole source of electrical power for drilling tools is driven by the rotation of a drillstring or, if the drillstring is not rotating, by the rotation of a drilling sub. The source consists of an alternator having a rotor made up of a series of coils that are mounted on, and spaced around the circumference of, a rotating drilling sub, and a stator made up of a multiplicity of permanent magnets also spaced around the circumference of the drilling sub. The stator is mounted on the drilling sub by means of bearings and incorporates a counterweight that holds the rotor relatively stationary with respect to the sub and with respect to the coils, so that rotation of the sub, either by rotation of the drillstring or by rotation of a drill motor in the drilling sub, produces relative rotation of the rotor and stator to generate an AC electrical output.

Abstract: A pair of elongated crossed coils is deployed in a first borehole and an instrument containing magnetic field sensors is deployed in a second borehole. The crossed coils are energized in quadrature by AC currents producing a rotating, elliptically polarized magnetic field at the second borehole. Mathematical analysis of the magnetic field sensor readings determines the location of the second borehole relative to the first. Both the distance and the rotational direction to the second borehole are determined as a function of depth of the sensors relative to that of the pair of crossed coils. Twisting of the long coil in the borehole is evaluated and the relative distance between the boreholes and the corrections needed due to such twisting are determined.

Abstract: An apparatus and method for measuring the location of one borehole relative to another includes a pair of elongated crossed coils deployed in the first borehole and an instrument containing magnetic field sensors deployed in the second borehole. The crossed coils are energized in quadrature by AC currents producing a rotating, elliptically polarized magnetic field at the second borehole. Mathematical analysis of the magnetic field sensor readings determines the location of the second borehole relative to the first. Both the distance and the rotational direction to the second borehole are determined as a function of depth of the sensors relative to that of the pair of crossed coils. No knowledge or measurement of the rotational orientation of the crossed coil in the first borehole is needed.

Abstract: Electrically powered electromagnetic field source beacons installed in a reference well in combination with a down-hole measurement while drilling (MWD) electronic survey instrument near the drill bit in the borehole being drilled permit distance and direction measurements for drilling guidance. Each magnetic field source beacon consists of a coil of wire wound on a steel coupling between two lengths of steel tubing in the reference well, and powered by an electronic package. Control circuitry in the electronic package continuously “listens” for, and recognizes, a “start” signal that is initiated by the driller. After a “start” signal has been received, the beacon is energized for a short time interval during which an electromagnetic field is generated, which is measured by the MWD apparatus.

Abstract: Measurement of the location and direction of a drill head in a borehole extending beneath an obstacle such as a body of water utilizes a single AC solenoid at a known location but having an unknown orientation. The measurements are used to direct the path of the borehole.

Abstract: A new and improved leg assisted forward facing rowing system is disclosed wherein a rower applies leg power to propel a boat by means of a rope connected between his or her foot and an oar. A unique feature is a roller, fastened under the heel of the rower's foot, that rolls along the bottom of the boat supporting the weight of the rower's leg while the reciprocating motion of the leg is transmitted by rope going through pulleys to reverse the force applied to the oar. The oar is pivoted at the center of the boat above the rower's knees by a mechanism that includes provision for applying lifting force to support the oar weight thereby holding the oar blade out of the water when no force is applied. The rower's legs, back and arms simultaneously apply rowing force. Feathering at the end of a stroke and squaring action at the beginning are provided by wrist action to rotate the oar blade.

Abstract: An electromagnetic method and apparatus for directional drilling guidance of horizontal boreholes for the installation of pipelines and communication cables beneath rivers, highways and other obstacles is disclosed. A solenoid source, with horizontal axes, generates alternating electromagnetic fields which are measured in the borehole by a magnetometer with known orientation with respect to the direction of gravity near the drill bit. A preferred embodiment has a useable range of 150 meters from the source.

Abstract: Apparatus and Methods are disclosed for determining the direction between a rotating magnetic field and alternating magnetic field sensors at a remote location. The curvature of a borehole drilling assembly between a rotating drill bit carrying a permanent magnet and sensors behind a drilling motor is measured to provide early indication of changes in drilling direction. A second application concerns measurement of the convergence and divergence and the skewness of two approximately parallel well bores to provide information for correcting the drilling direction to maintain parallelism. A third application measures the direction and distance to a point target to provide data for guiding drilling toward that target. The primary apparatus are an oriented, rotating permanent magnet and an oriented, three component alternating magnetic field sensor.

Abstract: An electromagnetic method and apparatus for directional drilling guidance of horizontal boreholes for the installation of pipelines and communication cables beneath rivers, highways and other obstacles is disclosed. A solenoid source, with horizontal axes, generates alternating electromagnetic fields which are measured in the borehole by a magnetometer with known orientation with respect to the direction of gravity near the drill bit. A preferred embodiment has a useable range of 150 meters from the source.

Abstract: An electromagnetic method and apparatus for directional drilling guidance of horizontal boreholes for the installation of pipelines and communication cables beneath rivers, highways and other obstacles is disclosed. A solenoid source, with horizontal axes, generates alternating electromagnetic fields which are measured in the borehole by a magnetometer with known orientation with respect to the direction of gravity near the drill bit. A preferred embodiment has a useable range of 150 meters from the source.

Abstract: An electromagnetic method and apparatus for directional drilling guidance of horizontal boreholes for the installation of pipelines and communication cables beneath rivers, highways and other obstacles is disclosed. A solenoid source, with horizontal axes, generates alternating electromagnetic fields which are measured in the borehole by a magnetometer with known orientation with respect to the direction of gravity near the drill bit. A preferred embodiment has a useable range of 150 meters from the source.

Abstract: Apparatus and Methods are disclosed for determining the direction between a rotating magnetic field and alternating magnetic field sensors at a remote location. The curvature of a borehole drilling assembly between a rotating drill bit carrying a permanent magnet and sensors behind a drilling motor is measured to provide early indication of changes in drilling direction. A second application concerns measurement of the convergence and divergence and the skewness of two approximately parallel well bores to provide information for correcting the drilling direction to maintain parallelism. A third application measures the direction and distance to a point target to provide data for guiding drilling toward that target. The primary apparatus are an oriented, rotating permanent magnet and an oriented, three component alternating magnetic field sensor.

Abstract: An apparatus and method for surveying the path of a borehole includes two single-axis field sensors located at a radius centered at a fixed location. Guide wires are located along the earth's surface above the prescribed borehole path and the known electromagnetic field produced by current in the guide wires are detected by the sensors. Values of X and Y vectors at multiple locations on a spherical surface at the radial distance of the sensors are calculated and compared with measured values to define the location of the sensors on the spherical surface to permit the lateral spacing between the sensors and the desired borehole path to be determined.