METHOD FOR WELL PATH MEASURING IN AZIMUTH AND DUAL-MODE BODY-MOUNTED GYROSCOPIC INCLINOMETER FOR ABOVE METHOD IMPLEMENTATION

摘要

FIELD: survey of boreholes or wells, particularly equipment to control spatial cased or uncased well position during well building.;SUBSTANCE: method involves measuring gravity acceleration projections onto measuring axes of borehole instrument, projections of Earth angular velocity onto corresponding sensitive axes of borehole instrument; measuring borehole instrument standoff angle during continuous movement and rotation thereof about longitudinal axis under the action of twisted logging cable, wherein in the first point of well path azimuth measuring the gyroscope is switched-on in angular velocity sensor mode for well azimuth determination and then gyroscope is switched to angle sensor mode and borehole instrument is switched to continuous motion mode to measure turn angles and then turn angle increment between measurements are determined; subtracting angle of gyroscope drift from Earth rotation from predetermined turn angle increment in X-direction to obtain turn angle increment in X-direction due to well path deviation; refining well path azimuth change in accordance with functional dependence obtained during inclinometer calibration with the use of testing rig; summing turn angle increment and full azimuth magnitude obtained at prior path point stop and performing continuous borehole instrument movement until turn angles reach maximal allowable values; stopping borehole instrument operation; shifting the gyroscope to angular velocity mode and repeatedly determining full well path azimuth value. Device comprises ground-based instrument connected to borehole instrument by cable. The borehole instrument comprises magneto-spherical gyroscope having angle sensors, namely sensors, which measure momentum along two measuring axes. Device also includes serially connected acceleration components generation unit and transmitting apparatus. Two control units to control mode of gyroscope operation are included in borehole instrument. The control units control gyroscope operation in X- and Y-directions and have the first and the second inputs connected to transmitting apparatus output and to control output of magneto-spherical gyroscope correspondingly. Control unit outputs are linked with data inputs of the transmitting apparatus. Each control unit comprises electronic switch, feedback voltage changer, the first and the second voltage summing units, two current sources for two coils of angle sensor, namely momentum sensor, differential amplifier, band-pass filter, phase-sensitive rectifier and integro-differential link. The first inputs of electronic switches are the first inputs of the control units, the second input of electronic switch in X-direction is linked with output of integro-differential link output in Y-direction. The second input of electronic switch in Y-direction is linked with output of integro-differential link output in X-direction. Output of electronic switch if each control unit is linked with summing units inputs through voltage changer. Outputs of summing units are connected with the first inputs of current sources having the second inputs linked with inputs of corresponding angle sensor coils. Angle sensor outputs are connected to inputs of differential amplifier having output connected to phase-sensitive rectifier input. Phase-sensitive rectifier output is connected to integro-differential link input. Phase-sensitive rectifier and integro-differential link outputs are outputs of the control unit, which controls gyroscope mode of operation.;EFFECT: increased accuracy and rate of well path measuring.;2 cl, 3 dwg