Abstract: A method and system for identifying bonding between a material and tubing. The method may include disposing an acoustic logging tool in a wellbore, wherein the acoustic logging tool comprises a transmitter, a receiver, or a transceiver, broadcasting a shaped signal with the transmitter such that the shaped signal interacts with a boundary of a casing and a material and recording a result signal from the boundary with the receiver. The method may further comprise identifying a cut-off time to be applied to the result signal, transforming the result signal from a time domain to a frequency domain, selecting one or more modes sensitive to a bonding at the boundary between the casing and the material, computing a decay rate of the one or more modes that were selected based at least one or more decay curves, and converting the decay rate to a bonding log.

Abstract: Aspects of the subject technology relate to systems and methods for identifying the quality of cement bonding of an exterior surface of a wellbore casing to an Earth formation. Methods of the present disclosure may allow for bond indexes to be identified in real-time as a cementing operation is performed even when tools that perform the cementing operation generate acoustic noise that interfere with measurements used to evaluate cement bonding quality. These methods may include transmitting acoustic signals, receiving acoustic signals, filtering the received acoustic signals, identifying magnitude and attenuation values to associate with the received acoustic signals, and comparing trends in the magnitudes with the identified attenuation values. These methods may also include correcting attenuation values associated with measured data based on a set of correction rules such that bond indexes can be identified. Such correction rules may be associated with data generated by a computer model.

Abstract: A method comprises conveying a downhole tool in a production tubing within a casing that is around a wall of a wellbore formed in a subsurface formation, wherein cement is placed in an annulus defined between the casing and the wall of the wellbore. The downhole tool includes at least one unipole receiver and a transmitter that comprises at least one of a unipole transmitter and a monopole transmitter. The transmitter and receiver are mounted on a rotatable portion of the downhole tool. The method includes performing the following operations at at least two azimuthal positions, emitting an acoustic transmission outward toward the cement and detecting an acoustic response that is in response to the acoustic transmission propagating through the production tubing and the casing and into the cement. The acoustic response includes casing extensional waves, casing non-extensional waves, and tubing waves. The method includes evaluating the cement based on the casing extensional waves.

Abstract: The disclosure presents processes to determine the direction and magnitude of tubing eccentricity along the length of a tube inserted within a borehole. The tubing can be a wireline, a drill string, a drill pipe, or tubing capable of allowing fluid or other material to flow through it. As borehole operations proceed, the tubing can move toward the side of the borehole. This eccentricity can cause excess wear and tear on the tubing, on the casing of the borehole, or on the inner surface of the subterranean formation. The eccentricity can be measured using acoustic signals that are collected downhole covering the azimuthal angles 0° to 360° at a location in the borehole. The collected signals can be filtered, transformed, and analyzed to estimate the tubing eccentricity. Other processes and systems can use the results to obtain cement bond evaluations through tubing and to determine preventative or restorative actions.

Abstract: Methods, systems, and program products are disclosed for implementing acoustic logging and determining wellbore material characteristics. In some embodiments, a method may include determining a polar differential signal for each of one or more pairs of azimuthally offset acoustic measurements within a wellbore. A reference azimuth is identified based, at least in part, on comparing the polar differential signals to a modeled bonding differential signal within a target response window. The method further includes determining differences between an acoustic measurement at the reference azimuth and acoustic measurements at one or more other azimuths and determining a wellbore material condition based, at least in part, on the determined differences.

Abstract: Methods and systems are disclosed for determining a material property transition within a wellbore. In some embodiments, a method includes determining a material transition profile for each of a plurality of test points within a linear measurement path including, for each test point, determining an acoustic response for a first location within the linear measurement path, and determining an acoustic response for a second location within the linear measurement path. The test point is between the first and second locations. The method further includes generating a material transition profile for the test point based, at least in part, on a difference between the acoustic response at the first location and the acoustic response at the second location.

Abstract: Methods and systems are disclosed for determining a material property transition within a wellbore. In some embodiments, a method includes determining a material transition profile for each of a plurality of test points within a linear measurement path including, for each test point, determining an acoustic response for a first location within the linear measurement path, and determining an acoustic response for a second location within the linear measurement path. The test point is between the first and second locations. The method further includes generating a material transition profile for the test point based, at least in part, on a difference between the acoustic response at the first location and the acoustic response at the second location.

Abstract: A method and system for identifying bonding between a material and tubing. The method may include disposing an acoustic logging tool in a wellbore, wherein the acoustic logging tool comprises a transmitter, a receiver, or a transceiver, broadcasting a shaped signal with the transmitter such that the shaped signal interacts with a boundary of a casing and a material and recording a result signal from the boundary with the receiver. The method may further comprise identifying a cut-off time to be applied to the result signal, transforming the result signal from a time domain to a frequency domain, selecting one or more modes sensitive to a bonding at the boundary between the casing and the material, computing a decay rate of the one or more modes that were selected based at least one or more decay curves, and converting the decay rate to a bonding log.

Abstract: Methods, systems, and program products are disclosed for implementing acoustic logging and determining wellbore material characteristics. In some embodiments, a method may include determining a polar differential signal for each of one or more pairs of azimuthally offset acoustic measurements within a wellbore. A reference azimuth is identified based, at least in part, on comparing the polar differential signals to a modeled bonding differential signal within a target response window. The method further includes determining differences between an acoustic measurement at the reference azimuth and acoustic measurements at one or more other azimuths and determining a wellbore material condition based, at least in part, on the determined differences.