Abstract: The present invention is directed to an apparatus for use on a structural member having a longitudinal axis. The structural member conducts a pressurized fluid in an operational state. The apparatus includes a housing member having a first end, a second end, and at least one protective enclosure configured to accommodate at least one device. The housing member moves on the structural member parallel to the longitudinal axis in the operational state with a substantially frictionless reciprocating motion. The housing member is rotationally registered to the structural member when coupled thereto. A first pneumatic isolator is formed at the first end and receives a first pressurized fluid portion of the pressurized fluid in the operational state to thus drive the housing member toward a second direction of the substantially frictionless reciprocating motion.

Abstract: Measurement of the inclination and azimuthal direction of a borehole extending beneath an obstacle, such as a body of water, which utilizes magnetic and gravity sensors at the drill bit of a borehole being drilled. Embodiments of the present invention determine and remove remanent field components and the effects of ferromagnetic permeability prior to and during drilling of the borehole.

Abstract: The present invention is directed to an apparatus for use on a structural member having a longitudinal axis, the structural member being configured to propagate stress wave energy in an operational state, the stress wave energy being characterized by an operational frequency spectrum. The apparatus has a housing assembly including a first end, a second end, and one or more protective enclosures configured to accommodate one or more devices. The housing assembly is configured to be rotationally registered to the structural member when coupled to the structural member, and is characterized by a predetermined housing mass. A spring arrangement is coupled between the structural member and the first end and/or coupled between the structural member and the second end in the operational state. The spring arrangement is characterized by a predetermined force-displacement relationship.

Abstract: Determining distance and direction from a first borehole to a second borehole including generating a time-varying magnetic field by axially reciprocating magnets of opposed polarity, at a first location in a second borehole, and detectable in the region of the first borehole. First and second sensors positioned at an observation point in the first borehole measure the amplitude and relative phase of components of the magnetic field. From these measurements, the direction, relative to the sensors, from an observation point to the first location is determined. The distance between these points is determined by measuring amplitude variations with depth of the magnetic field at observation points in the first borehole and computing theoretical variations in the amplitude for different assumed distances between the observation points and the location of the magnetic field source which are compared with theoretical variations to determine the distance between the first and second boreholes.

Abstract: The present invention is directed to tracking a borehole drilling direction and magnetic azimuth and orienting the tool face which controls the direction of drilling in a generally horizontal path between a specified borehole entry point and a predetermined exit location. The generally horizontal path may be disposed under a geographic obstacle such a river, a highway, a railroad, or an airport runway wherein the ground above the borehole is difficult or impossible to access.

Abstract: The present invention is directed to a system that has a first sensor assembly coupled to a mobile platform that traverses a predetermined subsurface path and has an axis of motion. The first sensor assembly obtains a gravity vector of the Earth relative to the mobile platform. A second sensor assembly is disposed in substantial alignment with a predetermined position relative to the axis of motion and is characterized by a sensitivity axis. The second sensor assembly provides a sensor signal substantially corresponding to a single vector component of the Earth's rotation vector. A control system is configured to derive the path direction relative to a known direction and an inclination angle of the mobile platform relative to the surface based on the gravity vector and the single vector component of the Earth's rotation vector.

Abstract: The present invention is directed to tracking a borehole drilling direction and magnetic azimuth and orienting the tool face which controls the direction of drilling in a generally horizontal path between a specified borehole entry point and a predetermined exit location. The generally horizontal path may be disposed under a geographic obstacle such a river, a highway, a railroad, or an airport runway wherein the ground above the borehole is difficult or impossible to access.

Abstract: The present invention is directed to a system that has a first sensor assembly coupled to a mobile platform that traverses a predetermined subsurface path and has an axis of motion. The first sensor assembly obtains a gravity vector of the Earth relative to the mobile platform. A second sensor assembly is disposed in substantial alignment with a predetermined position relative to the axis of motion and is characterized by a sensitivity axis. The second sensor assembly provides a sensor signal substantially corresponding to a single vector component of the Earth's rotation vector. A control system is configured to derive the path direction relative to a known direction and an inclination angle of the mobile platform relative to the surface based on the gravity vector and the single vector component of the Earth's rotation vector.

Abstract: An apparatus and method for surveying the path of a borehole includes three single-axis electromagnetic field sensors and three single axis gravity direction sensors in the borehole being surveyed. A pair of closely spaced, parallel guide wires carrying oppositely directed electric current in a reference borehole generate a known electromagnetic field, which is detected by the sensors. Mathematical analysis of electromagnetic and gravity measurements determines the lateral location and the direction of drilling in the neighboring borehole.

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.