Patent ID: 11965408
Assignee: VECTOR MAGNETICS, LLC
Field: Civil engineering (Other fields)
Classification: CPC E | IPC E

Claim 9:
10. The method of claim 9, wherein after the step of calculating multipliers for x, y and z magnetic field components and remanent magnetic field components associated with the at bit inclination and azimuth tool and drill bit and placing the downhole drilling assembly in a borehole underneath an Earth's surface, the method further comprising:
recording measurements from the first set of three axis magnetometer sensors and the first set of three axis inclinometer sensors of the at bit inclination and azimuth tool of the downhole drilling assembly in the borehole underneath the Earth's surface;
drilling the borehole a distance, such that the steering tool is relocated to a location of the at bit inclination and azimuth tool in which measurements from the first set of three axis inclinometer sensors and the first set of three axis magnetometer sensors in the at bit inclination and azimuth tool were previously recorded with the downhole drilling assembly in the borehole underneath the Earth's surface;
recording measurements from a second set of three axis steering tool magnetometer and a second set of three axis steering tool inclinometer sensors of a steering tool of the downhole drilling assembly in the borehole underneath the Earth's surface at the location;
recalculating multiplies for x magnetic field components, y magnetic field components, and remanent magnetic field components;
comparing recalculated multipliers for the x magnetic field components, the y magnetic field components and the remanent magnetic field components to the calibration x magnetic field component, the calibration y magnetic field component and the calibration z magnetic field component and the calibration remanent magnetic field components; and
retrieving the downhole drill assembly from the borehole if the recalculated multipliers for the x magnetic field components, the y magnetic field components and the remanent magnetic field components differ by greater than two degrees from the calibration x magnetic field component, the calibration y magnetic field component and the calibration z magnetic field component and the calibration remanent magnetic field components for recalibration of the downhole drilling assembly.