Electromagnetic pipe inspection inversion with adaptive filter for artifact removal

Patent metadata

Field	Value
Publication number	US-12013370-B2
Application number	US-202217850008-A
Country	US
Kind code	B2
Filing date	Jun 27, 2022
Priority date	Jun 27, 2022
Publication date	Jun 18, 2024
Grant date	Jun 18, 2024

Abstract

Aspects of the subject technology relate to systems, methods, and computer-readable media for accounting for artifacts in pipe measurements made by an electromagnetic pipe inspection tool. Measurements gathered in a plurality of pipes across different depth points are accessed. Initial estimates of an attribute associated with the plurality of pipes are made for each pipe and a total estimate of the attribute for the plurality of pipes as a whole are made across the different depth points. Corresponding initial estimates of the attribute for each pipe are filtered to remove an artifact present in at least one of the corresponding initial estimates while the total estimate is preserved. Corresponding final estimates of the attribute for each pipe are determined based on both the measurements and corresponding filtered initial estimates of the attribute for each pipe. Integrity of each pipe can be determined based on the corresponding final estimates of the attribute.

First claim

What is claimed is:

1. A method comprising:
accessing measurements at different depth points of a plurality of pipes in a downhole environment;
determining an initial estimate of an attribute associated with the plurality of pipes for each pipe of the plurality of pipes across the different depth points based on the measurements;
identifying a total estimate of the attribute for the plurality of pipes as a whole across the different depth points;
filtering the corresponding initial estimates of the attribute for the each pipe of the plurality of pipes to remove an artifact present in at least one of the corresponding initial estimates of the attribute present across at least a portion of the different depth points while preserving the total estimate of the attribute;
determining corresponding final estimates of the attribute for the each pipe of the plurality of pipes based on both the measurements and corresponding filtered initial estimates of the attribute for the each pipe of the plurality of pipes; and
identifying an integrity of a pipe of the plurality of pipes based on a corresponding final estimate of the attribute for the pipe.

2. The method of claim 1 , wherein the measurements are gathered by an electromagnetic pipe inspection tool with at least one transmitter coil and at least one receiver coil.

3. The method of claim 2 , wherein the electromagnetic pipe inspection tool operates either in a time-domain or a frequency-domain.

4. The method of claim 1 , wherein determining the initial estimate of the attribute for each pipe of the plurality of pipes includes applying calibration, applying model-based inversion, applying supervised machine learning, or a combination thereof.

5. The method of claim 4 , wherein the model-based inversion is a radial one-dimensional inversion.

6. The method of claim 1 , wherein the attribute associated with the plurality of pipes includes a thickness of the each pipe of the plurality of pipes, a magnetic permeability of the each pipe of the plurality of pipes, an electrical conductivity of the each pipe of the plurality of pipes, and an eccentricity between pipes of the plurality of pipes.

7. The method of claim 1 , wherein filtering the corresponding initial estimates of the attribute for the each pipe of the plurality of pipes to remove the artifact further comprises:
comparing derivatives of the corresponding initial estimates of the attribute for the each pipe of the plurality of pipes to derivatives of the total estimate of the attribute for the plurality of pipes with respect to depth of the different depth points;
flagging depth intervals based on differences between absolute values of the derivatives of the corresponding initial estimates of the attribute for the each pipe of the plurality of pipes and absolute values of the derivatives of the total estimate of the attribute for the plurality of pipes in relation to a specific threshold;
excluding flagged depth intervals from the corresponding initial estimates of the attributes for the each pipe of the plurality of pipes to create gaps in the corresponding initial estimates of the attribute;
supplementing the gaps through interpolation to obtain a filtered initial estimate of the attribute for a pipe of the plurality of pipes.

8. The method of claim 7 , wherein the process of comparing the derivatives, flagging and excluding depth intervals, and interpolation is repeated iteratively until the differences between the absolute values of the derivatives of the corresponding initial estimates of the attribute for the each pipe of the plurality of pipes and the absolute values of the derivatives of the total estimate of the attribute for the plurality of pipes are less than or equal to the specific threshold across at least a portion of the different depth points.

9. The method of claim 7 , wherein the process of filtering the corresponding initial estimates of the attribute for the each pipe of the plurality of pipes is applied sequentially to different pipes in an arbitrary order.

10. The method of claim 7 , wherein either or both the derivatives of the corresponding initial estimates of the attribute and the derivatives of the total estimate of the attribute include a first derivative as well as higher order derivatives with respect to depth.

11. The method of claim 7 , wherein the specific threshold is 30%, 20%, 10%, or 0%.

12. The method of claim 1 , wherein the total estimate of the attribute for the plurality of pipes as whole is identified by either summing up the corresponding initial estimates of the attribute or a filtered version of a sum of the corresponding initial estimates of the attribute.

13. The method of claim 1 , wherein the total estimate of the attribute is identified directly from the measurements using a process that is substantially different from a process used to calculate the corresponding initial estimates of the attribute.

14. The method of claim 1 , wherein the artifact arises from RID model mismatch created when a tool that gathers the measurements encounters 2-D features or from an inherent non-uniqueness of an applied inversion process.

15. The method of claim 1 , wherein the corresponding final estimates of the attribute are used as an initial guess to a second inversion.

16. A method comprising:
accessing measurements at different depth points of a plurality of pipes in a downhole environment;
determining a total estimate of thickness for the plurality of pipes as a whole across the different depth points based on the measurements;
determining corresponding initial estimates of the thickness for each pipe of the plurality of pipes based on the measurements;
filtering the corresponding initial estimates of the thickness for the each pipe to remove an artifact present in at least one of the corresponding initial estimates of the thickness across at least a portion of the different depth points, wherein:
the corresponding initial estimates of the thickness for the each pipe are filtered based on the total estimate of thickness for the plurality of pipes as the whole;
the filtering is performed while preserving the total estimate of the thickness for the plurality of pipes as the whole; and

identifying an integrity of a pipe of the plurality of pipes based on a corresponding filtered initial estimate of the thickness of the pipe.

17. The method of claim 16 , wherein the total estimate of the thickness for the plurality of pipes as the whole is calibrated to a cumulative sum of the corresponding initial estimates of the thickness for the each pipe and a calibrated total estimate of the thickness for the plurality of pipes as the whole is applied in filtering the corresponding initial estimates of the thickness for the each pipe.

18. The method of claim 17 , wherein the calibration comprises curve fitting between the total estimate of the thickness for the plurality of pipes as the whole and the cumulative sum of the corresponding initial estimates of the thickness for the each pipe.

19. The method of claim 16 , wherein the total estimate of the thickness for the plurality of pipes as the whole is computed directly from the measurements using either a regression function or a machine learning model.

20. A system comprising:
one or more processors; and
at least one computer-readable storage medium having stored therein instructions which, when executed by the one or more processors, cause the one or more processors to:
access measurements at different depth points of a plurality of

Assignees

• Halliburton Energy Services Inc

Inventors

• Fouda Ahmed E
• Dai Junwen
• Hill Freeman L

Classifications

• G01B7/10 Primary

  using magnetic means, e.g. by measuring change of reluctance · CPC title

• G01V3/28

  using induction coils · CPC title

• G01N27/82 Primary

  for investigating the presence of flaws · CPC title