US 11,656,199 B2
System and method for obtaining and analyzing flux leakage data in the inspection of oil and gas wells
Yong-Hua Chen, Belmont, MA (US); Dzevat Omeragic, Lexington, MA (US); and Tarek M. Habashy, Burlington, MA (US)
Assigned to SCHLUMBERGER TECHNOLOGY CORPORATION, Sugar Land, TX (US)
Appl. No. 17/253,775
Filed by SCHLUMBERGER TECHNOLOGY CORPORATION, Sugar Land, TX (US)
PCT Filed Jun. 19, 2019, PCT No. PCT/US2019/037922
§ 371(c)(1), (2) Date Dec. 18, 2020,
PCT Pub. No. WO2019/246212, PCT Pub. Date Dec. 26, 2019.
Claims priority of provisional application 62/690,123, filed on Jun. 26, 2018.
Claims priority of provisional application 62/686,873, filed on Jun. 19, 2018.
Prior Publication US 2021/0285915 A1, Sep. 16, 2021
Int. Cl. G01N 27/83 (2006.01); E21B 47/00 (2012.01); E21B 47/092 (2012.01); G01M 3/04 (2006.01)
CPC G01N 27/83 (2013.01) [E21B 47/006 (2020.05); E21B 47/092 (2020.05); G01M 3/04 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method of improving flux leakage data to remove a sensor liftoff effect comprising:
measuring, using a magnetic flux leakage tool, magnetic flux leakage data from a casing;
determining sensor liftoff data from the magnetic flux leakage data;
performing outward analytic continuation of the magnetic flux leakage data from a sensor plane to one or more additional planes; and
extrapolating back from the one or more additional planes to a surface; wherein extrapolating back includes a linear extrapolation approach.