RFEC Total Thickness Logging via Segmented Inversion
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Solution Overview
Problem
Incorporating the description of the technical problem from the patent description.
Innovation Solution
The patent introduces remote-field eddy current (RFEC)-based techniques for quickly deriving total thickness measurements using a multi-array electromagnetic logging tool, which allows for real-time monitoring of pipe corrosion in nested, concentric arrangements by employing phase difference measurements from multiple TRF combinations to estimate total wall thickness, enabling immediate feedback and focused inversion on potentially problematic regions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If electromagnetic tools with multiple transmit and receive antennas are used to acquire measurements with different antenna spacings and frequencies, then the wall thickness of each pipe in a nested arrangement can be determined, but the inversion process becomes computationally intensive and cannot be conducted in real time
Solution Approach 1:
The patent segments the inversion process by first acquiring all necessary measurements (multiple antenna spacings and frequencies) during the logging operation, then performing the computationally intensive inversion process separately in a post-processing stage. This segmentation allows the logging tool to focus on data collection without being constrained by real-time computational requirements, while still enabling timely availability of corrosion assessment results through offline processing.
Solution Approach 2:
The patent applies preliminary action by pre-acquiring all electromagnetic measurements during the logging operation before the inversion process is performed. The measurements are stored and then processed in batches or in advance, allowing the complex inversion to be completed before final results are needed, thus enabling real-time or near-real-time availability of corrosion assessments without requiring real-time computational inversion during the logging process.
2Reliability
If the inversion process is performed to determine wall thickness of each pipe, then accurate corrosion monitoring is achieved, but the computational intensity prevents real-time feedback
Solution Approach 1:
The patent segments the workflow into two distinct phases: a data collection phase during logging where all electromagnetic measurements are acquired and stored, and a separate inversion phase where the computationally intensive processing is performed. This segmentation eliminates the need for real-time inversion during logging, reducing feedback time by allowing batch processing of measurements after logging is complete or in advance of final analysis requirements.
Solution Approach 2:
The patent performs preliminary data acquisition during the logging operation, storing all necessary measurements before the inversion process. This preliminary action allows the complex inversion to be performed in advance or in batches, significantly reducing the time between measurement completion and results availability, thereby enabling timely feedback for corrosion monitoring without requiring real-time computational inversion.
3Measurement precision
If multiple TRF combinations are used to measure phase difference, then total thickness can be estimated, but the complexity of processing increases
Solution Approach 1:
The patent segments the processing of multiple TRF combinations by treating each combination's phase difference measurements independently, then combining the results through a systematic inversion process. This segmentation allows complex measurements from multiple TRF combinations to be managed and processed in an organized manner, reducing overall processing complexity while maintaining measurement precision through comprehensive data utilization.
Solution Approach 2:
The patent applies multi-functionality by using the same electromagnetic logging tool and measurement framework to simultaneously obtain data from multiple TRF combinations, each contributing to the total thickness estimation. The unified processing approach handles all TRF combinations through a single inversion framework, reducing complexity compared to separate processing of each combination while maintaining comprehensive measurement precision.
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 provides accurate and efficient real-time monitoring of pipe corrosion, allowing for prompt corrective actions and reducing computational intensity, thereby preventing fluid loss and formation damage in subsurface reservoirs.
Implementation Method 1
remote-field eddy current (RFEC)-based techniques for quickly deriving a total thickness measurement from a multi-array electromagnetic logging tool
Implementation Method 2
employing phase difference measurements from multiple TRF combinations to estimate total wall thickness
Data Source
AI summary
Eddy current logging enables corrosion monitoring in nested-pipe arrangements. An illustrative method of logging total thickness of the pipe walls includes acquiring measurements from an electromagnetic logging tool conveyed through the innermost bore, each measurement associated with a TRF combination (transmit antenna, receive antenna, and frequency), and further associated with a position along the bore. Multiple scale factors are applied to the measurements to determine multiple total thickness estimates for each position, each of the multiple scale factors corresponding to a subset of single-pipe defect profiles. Preferably, every possible single-pipe defect profile is included in at least one of these subsets. A total thickness log value for each position is derived from the multiple total thickness estimates for that position, and the derived total thickness log values are used to update a displayed total thickness log as the measurements are being acquired.