Artificial Magnetic Toolface for Vertical Borehole Kickoff

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

In directional borehole drilling, especially in vertical or near-vertical wells, existing methods for determining the toolface angle are unreliable due to limitations in using accelerometers and magnetic toolface, which can fail at high magnetic latitudes or be affected by interference, and gyroscopes are costly and unreliable.

Innovation Solution

An artificial toolface reference system is introduced, which generates a reference magnetic field along a conductor in a reference wellbore using a power supply and grounding points, allowing a guidance sensor outside the wellbore to measure this field and determine the toolface angle, even in challenging environments.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If magnetic toolface is used to determine toolface angle in vertical wells, then it provides a reference direction using Earth's magnetic field, but it fails at high magnetic latitudes or where magnetic interference from nearby wellbores or surface facilities alters the local magnetic field

Engineering Contradiction:

Improvetoolface angle measurementVSAvoidmagnetic field reference

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The patent introduces a reference conductor as an intermediary element that generates a controlled reference magnetic field. This reference magnetic field serves as a mediator between the magnetometer and the toolface determination, replacing the unreliable Earth's magnetic field. The reference conductor carries current to produce a known magnetic field pattern that the magnetometer can use to determine toolface angle independently of external magnetic interference.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Measurement precision

If accelerometers are used to determine toolface angle in deviated wellbores, then gravity reference direction is available, but in vertical or near-vertical wells the gravity direction aligns with the drill string axis and cannot provide a useful reference direction

Engineering Contradiction:

Improvetoolface angle measurementVSAvoidreference direction availability

Core Design Contradiction:

Measurement precisionVSAdaptability or versatility

Solution Approach 1:

The patent changes the fundamental parameter used for reference from gravity-based (accelerometer) or Earth magnetic field-based to an artificially generated magnetic field from a reference conductor. This parameter change enables toolface determination in vertical wells where the gravity reference becomes unavailable, as the artificial magnetic field reference does not depend on well inclination or Earth's magnetic field orientation.

Inventive Principle:

Principle #35Parameter changes

3Reliability

If gyroscopes are used to provide true North reference, then reliable reference direction is obtained, but cost and reliability concerns arise

Engineering Contradiction:

Improvereference directionVSAvoidcost and reliability

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent replaces expensive, complex gyroscopes with a simple reference conductor and magnetometer system. The reference conductor is a basic electrical component that generates a magnetic field, and the magnetometer is a standard sensing device. This substitution dramatically reduces cost and complexity while maintaining reliability, as the artificial magnetic field reference can be precisely controlled and measured without the mechanical complexity of gyroscopes.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This system provides a reliable and cost-effective method for determining the toolface angle by isolating the reference magnetic field from natural and interference fields, enabling accurate borehole steering and placement in various drilling conditions.

Implementation Method 1

providing a current, with the power supply, through the reference conductor, the ground, and the ground point such that a reference magnetic field is generated along the reference conductor

Methodology Applied

Scientific EffectElectromagnetic field generation: Electromagnet

Implementation Method 2

measuring the reference magnetic field with a magnetometer positioned outside of the reference wellbore

Methodology Applied

Scientific EffectMagnetic field detection: Magnetometer

Data Source

PatentUS9938773B2Active magnetic azimuthal toolface for vertical borehole kickoff in magnetically perturbed environments

Publication Date: 2018.04.10 APPLIED TECHNOLOGIES ASSOCIATES INC

AI summary

An artificial toolface reference system includes a power supply providing current to a ground lead and a reference lead. A ground point is coupled to the ground lead and in electrical connection with the ground. A reference wellbore includes a reference conductor in electrical connection with the ground. The reference conductor is in electrical connection with the reference lead. A guidance sensor positioned outside the reference wellbore includes at least one magnetometer. The power supply may be used to provide a current through the reference conductor, the ground, and the ground point such that a reference magnetic field is generated along the reference conductor. The guidance sensor may measure the reference magnetic field with a magnetometer. An artificial magnetic toolface may be calculated therefrom.