Thickness value restoration in eddy current pipe inspection

A machine-readable storage device having instructions stored thereon, which, when executed by control circuitry of a machine, cause the machine to perform operations, the operations comprising:

• generating a set of log measurements obtained using an electromagnetic pulsed tool disposed in multiple nested conductive pipes in a wellbore, and forming a measured log having measurement data at different depths in the multiple nested conductive pipes;
• processing the set of log measurements to generate thickness estimations of the multiple nested conductive pipes:
• generating a set of small defect log measurements based on at least one of the multiple nested conductive pipes having a small defect:
• processing the set of small defect log measurements to generate small defect thickness estimations;
• and
• solving a system of equations involving the thickness estimations and the small defect thickness estimations to generate a set of curves that represent thickness variations for the multiple nested conducted pipes over the different depths.

A system comprising:

• a tool, the tool being an electromagnetic pulsed tool having a transmitter coil and a receiver coil arranged such the receiver coil receives a secondary field in response to a primary field generated from the transmitter coil;
• and
• control circuitry configured to:
• evaluate multiple nested conductive pipes in a wellbore from a set of log measurements acquired by use of the tool disposed in the multiple nested conductive pipes operable to form a measured log of measurement data at different depths in the multiple nested conductive pipes;
• process the set of log measurements to generate thickness estimations of the multiple nested conductive pipes;
• generate a set of small defect log measurements based on at least one of the multiple nested conductive pipes having a small defect;
• process the set of small defect log measurements to generate small defect thickness estimations;
• and
• solve a system of equations involving the thickness estimations and the small defect thickness estimations to generate a set of curves that represent thickness variations for the multiple nested conducted pipes over the different depths.