DETERMINATION OF WELL ANGULAR ORIENTATION Russian patent published in 2015 - IPC E21B47/22 

FIELD: instrumentation.

SUBSTANCE: claimed comprises the steps that follow. Geomagnetic field complete vector components are measured with the help of three mutually perpendicular ferroprobes. Readings of three mutually perpendicular accelerometers are used to define the gravity full vector components to compute therefrom the intermediate magnitudes of azimuthal and zenith angles. Then, errors are defined to computer the well target azimuthal and zenith angles for every measurement points. Note here that before measurements in the well, systematic errors of ferroprobes and accelerometers are defined. Expected rate of the change in said angles are defined in drilling process. Geomagnetic field complete vector components and gravity magnitude are defined in drilling site. Besides, additionally measured is the vibration level by accelerometers. At low vibrations level, data are accumulated to calculate the error for external magnetic interferences and to calculate the azimuthal, zenith angles and deflector setting angle with due allowance for predefined systematic errors, expected reading of geomagnetic field in drilling site and expected rate of the change in well angles at drilling. At high vibrations level, calculated, preferably, are the refined the deflector setting angle with allowance for current readings of ferroprobes. Note here that vibrations are measured with the help of the second three-axis accelerometer that features higher sensitivity to vibrations.

EFFECT: higher accuracy of well parameters determination.

2 cl