Abstract: The invention relates to devices for measuring the azimuth and the slope of drilling line. These devices comprise, in a container 1, a gyroscope 5 having two principal axes of sensitivity X--X and Y--Y and an accelerometer 12 having two principal axes of sensitivity parallel to those of the gyroscope 5; this gyroscope 5 is connected to a circuit to determine the component of the Earth's rotation vector along the axis of the drilling line.

Abstract: A device for continuously measuring the azimuth and slope of a drilling l includes a gyroscope and an accelerometer station disposed in a container suspended from a cable. The gyroscope and the accelerometer station are mounted on an inner frame pivotally mounted on an outer frame on an axis which is perpendicular both to the axis of rotation of the gyroscope and the axis of the drilling line. The outer frame is pivotally mounted in the container on the longitudinal axis of the container. An angular position detector measures the angular movements of the inner frame in relation to the outer frame. A first motor controlled by stabilization error information delivered by the gyroscope and corresponding to one axis of gyroscope sensitivity rotates the inner frame in relation to the outer frame, and a second motor controlled by stabilization error information delivered by the gyroscope and corresponding to a second axis of sensitivity rotates the outer frame in relation to the container.

Abstract: Improved apparatus for measuring the angular deviation from the vertical of the end of the drill string which includes a housing adapted for insertion in the drill string, a pendulum pivotally mounted in the housing and capable of swinging through large angles, and a substantially perfectly balanced catch link pivoted at the same point as the pendulum and normally coaxially aligned with the end of the drill string. Means are provided for coupling the pendulum and catch link together at a preselected angle and for measuring the deflection of the coupled pendulum and catch link from the axis of the end of the drill string so that the angular deviation from the vertical of the end of the drill string may be determined. Means are provided for signalling the measure of the deflection to the surface.

Abstract: A method of measuring the deviation of the run of the actual vertical center axis of fluid filled bore holes and trenches relative to the direction of the design center axis thereof which bore holes and trenches are excavated under bentonite slurry comprises inserting into said bore holes and trenches a gauge means suspended from a cable means, whereby said gauge means is arrested inside said bore hole at any desired level, and thereafter a measuring cable means is connected to said gauge means and substantially tensioned and brought to run in an exact vertical direction whereupon above ground level the horizontal deviation of said cable means from the design center line of said bore hole or said trench is measured.

Abstract: A reversible baffle plate for receiving and supporting a bottom hole survey apparatus on the interior of a directional drilling string is characterized by concentrically disposed inner and outer members supported one from the other by a plurality of webs. The webs cooperate with the inner and outer members to define a plurality of flow passages through the baffle plate. The first and second axial ends of the inner tubular member are each adapted to receive and support the lowermost axial end of a bottom hole survey apparatus.

Abstract: Mapping apparatus comprises:(a) a gyroscope and a carrier frame therefor,(b) the gyroscope characterized as having a spinning rotor and torsion structure defining a gimbal, and wherein the rotor spin frequency has a predetermined relation to a resonant frequency of said structure,(c) the gyroscope further characterized as having two input axes, and an output axis about which the spin rotor rotates,(d) drive means operatively connected with said frame to rotate the frame about one of said axis, and(e) the gyroscope having means to detect rotor pivoting about one of said two input axes in response to said rotation of the frame.A second gyroscope may be employed, with its frame. rotated by the same drive means; and the output axes of the two gyroscopes are typically orthogonally related.

Abstract: Survey apparatus and method employs one or more rate gyroscopes having spin axis components directed along an instrument travel axis and in also in directions normal to the travel axis, so that when the gyroscope or gyroscopes are rotated, the earth's rate of rotation will be detected, at all latitudes and at all instrument attitudes.

Abstract: The invention contemplates use of a single magnetic-field (flux) sensor mounted within an elongate probe housing, to continuously generate telemetered electric signals from which the instantaneous orientation of the housing is at all times known and from which changes in orientation may be tracked as a function of probe depth within the borehole in which the probe housing may be displaced. The telemetered electric signals provide accurate and current indications of (a) magnitude of the horizontal component of the earth's magnetic-field lines, (b) direction and magnitude of probe-axis tilt with respect to the gravitational vertical, and the direction of the earth's magnetic field, and (c) a probe-housing frame-angle reference; provision being made within the probe housing for performing substantially all discriminating, detecting and other problem-solving functions, whereby the telemetered signals are directly utilizable by recording and/or display equipment at surface end of the borehole site.

Abstract: A bottom hole survey apparatus is characterized by a survey instrument having a reference line therein, the instrument being receivable by the engagement of flanges provided along the instrument into keyways provided on the interior of a non-magnetic instrument barrel. When engaged, the reference line of the survey instrument is disposed in a predetermined angular relation with respect to the barrel. The barrel has means provided on the exterior thereof for receiving a visual sighting element thereon, the sighting element being in a predetermined angular relationship with respect to the reference line. At least one non-magnetic spacer element is connectable to the barrel, the spacer element being provided with an adapter having a T-shaped head thereon which is received within a corresponding T-shaped groove provided at the lower end of the instrument.

Abstract: The apparatus includes a housing in which a frame is rotationally mounted, an instrument which is pivotally mounted about two axes within said frame, level sensing devices on the instrument to detect the tilt of the instrument about said two axes, and means for tilting the instrument within the frame so that the instrument's reference axis may be brought to a substantially vertical position when the apparatus is within an inclined well bore. The instrument is mounted unsymmetrically within the frame so that the instrument may be tilted in one direction on one axis a much greater amount than on the other axis and in the other direction.

Abstract: A borehole sensor is presented including a three axis gimbal device for determining (1) a vertical plane, using the force of gravity as a reference, (2) a horizontal plane, using the force of gravity as a reference, and (3) the north direction, using the earth's magnetic field as a reference. A motor drive system drives parts of the mechanism to desired positions about the three axes, and error transducers determine the deviation from desired positions about the axes and provide feedback to the motor drive system to eliminate the error.

Abstract: An apparatus for examining the interior of a bore hole and/or caisson. The apparatus includes a gyroscope arrangement for determining true azimuth reference and slant angle and slant angle azimuth direction relative to the reference. A television camera including a lighting section is fixed relative to the gyroscope package by a cage which is adapted for slidingly engaging the interior of the bore hole and/or caisson so that the gyroscope package can make effective determinations relative to the same in order to enable establishing the location of the television camera. A remote control is provided for controlling the lowering of the cage into the bore hole and/or caisson and for controlling the television camera as well as the lighting arrangement therefor. A television monitor is employed which is connected to the camera for displaying scenes of the interior as the gyroscope and camera arrangement is lowered through the bore hole and/or caisson.

Abstract: Borehole orienting apparatus is provided wherein motion is imparted to a permanent magnet assembly to generate a moving magnetic field and receiver means are provided such that measurable signals are induced therein when the magnetic field is distorted due to the presence of a ferrous anomaly. The receiver means is rotated to produce an azimuthal scan such that there are induced in the receiver means signals from which the azimuthal location of the anomaly can be determined.