Measurement of inclination and true vertical depth of a wellbore
AssigneeHalliburton Energy Services, Inc.
InventorStephen Daniel Lloyd
Life of this patent
Estimating the term…
Abstract
The accuracy of directional surveys may be improved using accelerometers, magnetometers, or both. A control system containing accelerometers is configured specifically to correct errors in bias and gain of each accelerometer by requiring the measured field strengths to be as constant as possible over several tool face angles over multiple points in a wellbore, even when all measurements are within a tangent or lateral section of a wellbore. Corrections for the bias and gain errors determined based on one or more measurements from the accelerometers are applied to measurements at other survey points to improve the accuracy of surveys and the efficiency of drilling operations.
Claims18
A measurement system, comprising:
- a drill string;
- and
- an inclination sensor mounted on the drill string, the inclination sensor comprising:
- an inclination sensor body;
- a set of accelerometers, wherein the set of accelerometers comprises a first accelerometer, a second accelerometer, and a third accelerometer, wherein the first accelerometer, the second accelerometer, and the third accelerometer are disposed out of alignment with the drill string, wherein each of the first accelerometer, the second accelerometer, and the third accelerometer comprise a measurement axis, and wherein the measurement axis of each of the first accelerometer, the second accelerometer, and the third accelerometer is out of alignment with a longitudinal axis of the drill string, wherein the set of accelerometers further comprises a fourth accelerometer, wherein the fourth accelerometer comprises a measurement axis parallel to the longitudinal axis of the drill string;
- an electronics package, wherein the electronics package receives one or more measurements from at least one accelerometer of the set of accelerometers.
A method for determining an inclination of a borehole within a formation, comprising:
- obtaining, by a set of accelerometers of an inclination sensor disposed on a drill string in the borehole, one or more accelerometer measurements, wherein the set of accelerometers comprises a first accelerometer, a second accelerometer, and a third accelerometer, wherein each of the first accelerometer, the second accelerometer, and the third accelerometer comprises a measurement axis, and wherein the measurement axis of each of the first accelerometer, the second accelerometer, and the third accelerometer is out of alignment with a longitudinal axis of the drill string, wherein the set of accelerometers further comprises a fourth accelerometer, wherein the fourth accelerometer comprises a measurement axis parallel to the longitudinal axis of the drill string;
- correcting for measurement error at least one of the one or more accelerometer measurements;
- determining at least one of an orientation or an inclination of the inclination sensor based, at least in part, on the corrected at least one of the one or more accelerometer measurements;
- and
- adjusting one or more drilling parameters based, at least in part, on the at least one of orientation or inclination of the inclination sensor.
A non-transitory storage computer-readable medium storing one or more instructions that, when executed by a processor, cause the processor to:
- obtain, by a set of accelerometers of an inclination sensor disposed on a drill string in a borehole, one or more accelerometer measurements, wherein the set of accelerometers comprises a first accelerometer, a second accelerometer, and a third accelerometer, wherein each of the first accelerometer, the second accelerometer, and the third accelerometer comprises a measurement axis, and wherein the measurement axis of each of the first accelerometer, the second accelerometer, and the third accelerometer is out of alignment with a longitudinal axis of the drill string, wherein the set of accelerometers further comprises a fourth accelerometer, wherein the fourth accelerometer comprises a measurement axis parallel to the longitudinal axis of the drill string;
- and
- correct for measurement error at least one of the one or more accelerometer measurements;
- determine at least one of an orientation or an inclination of the inclination sensor based, at least in part, on the corrected at least one of the one or more accelerometer measurements;
- and
- adjust one or more drilling parameters based, at least in part, on the at least one of orientation or inclination of the inclination sensor.
Dependencies are inferred from the claim text.