Patent ID: 11905816
Assignee: HALLIBURTON ENERGY SERVICES, INC.
Field: Measurement (Instruments)
Classification: CPC E  G | IPC E  G

Claim 0:
1. A method comprising:
measuring a pulse-echo waveform with an ultrasonic logging tool disposed interior to a borehole casing;
extracting, from the measured pulse-echo waveform, a reflection portion corresponding to a reflection off an interface between the borehole casing and a borehole fluid contained within the borehole casing;
computing, for each of a plurality of casing thicknesses, a synthetic frequency spectrum as a weighted sum of plane-wave echo waveforms simulated for the respective casing thickness across a range of frequencies, using the reflection portion extracted from the measured pulse-echo waveform as a driving pulse to weight the simulated plane-wave echo waveforms;
correlating a frequency spectrum of the measured pulse-echo waveform with the synthetic frequency spectra computed for the plurality of casing thicknesses to obtain a correlation coefficient as a function of casing thickness; and
determining a thickness of the borehole casing based on a maximum of the correlation coefficient.