Drilling Assembly Magnetic Field Navigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drilling technologies face challenges in navigating a drill string through a reservoir layer of an earth formation without straying into adjacent conductive formations, as they lack effective methods to differentiate and steer within non-conductive reservoir layers based on electromagnetic properties.
Innovation Solution
The method involves positioning a drilling assembly within a reservoir between conductive upper and lower layers, using sensors to measure the magnetic fields generated by these layers, and employing a processor to steer the assembly based on these measurements, allowing for precise navigation by determining locations where the magnetic field is zero or calculating distances to the conductive layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional drilling technologies are used, then drilling operations can be performed, but the drill string cannot effectively differentiate and steer within non-conductive reservoir layers based on electromagnetic properties
Solution Approach 1:
The patent replaces conventional mechanical/electrical steering systems with a magnetic field-based navigation system. Magnetic sensors detect DC magnetic fields generated by conductive boundary layers, enabling the drill string to determine its position and steer accurately within non-conductive reservoir layers where traditional electromagnetic methods fail.
Solution Approach 2:
The patent introduces DC magnetic fields as an intermediary mechanism. Conductive boundary layers generate DC magnetic fields that penetrate non-conductive reservoir layers, serving as a mediator that allows the drill string to detect boundary layer positions and steer without direct electromagnetic contact with the non-conductive formation.
2Reliability
If the drill string uses traditional navigation methods, then drilling can proceed, but the drill string may stray into adjacent conductive formations
Solution Approach 1:
The patent implements a feedback control system where magnetic sensors continuously monitor DC magnetic field strengths, the processor compares readings to determine drift toward boundary layers, and the steering system adjusts the drill string position in real-time to maintain centered navigation within the reservoir layer.
Solution Approach 2:
The patent performs preliminary detection of DC magnetic field characteristics before drilling begins and establishes baseline field strength profiles. This preliminary action enables the system to predict boundary layer positions and proactively adjust steering to prevent drift into adjacent formations before it occurs.
3Loss of information
If no magnetic field measurement system is used, then the drilling assembly cannot determine its position, but the system remains simpler
Solution Approach 1:
The patent employs a self-service approach where the conductive boundary layers themselves generate the DC magnetic fields used for navigation. The formation's natural electrical properties create the signaling field, eliminating the need for external field generation equipment and reducing overall system complexity while providing continuous position information.
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 approach enables accurate steering of the drilling assembly within the reservoir by utilizing the differences in DC magnetic fields, ensuring that the drill string remains within the target layer and avoids adjacent conductive formations, thereby improving the efficiency and accuracy of horizontal drilling operations.
Implementation Method 1
measuring a magnetic field at the drilling assembly resulting from a DC magnetic field at an upper formation layer above the reservoir and a DC magnetic field at a lower formation layer below the reservoir
Data Source
AI summary
A method and apparatus for steering a drilling assembly within a reservoir of an earth formation is disclosed. The drilling assembly is positioned within the reservoir between a conductive upper layer having a DC magnetic field and a conductive lower layer having a DC magnetic field. A sensor of the drilling assembly measures a magnetic field in the reservoir resulting from the DC magnetic field of the conductive upper layer and the DC magnetic field of the conductive lower layer. A processor uses the measured magnetic field to steer the drilling assembly within the reservoir.