Processing and joint interpretation using multiple borehole acoustic waves for through tubing cement evaluation

A system comprising:

• an acoustic logging tool disposed within a tubing located inside a casing in a cased-borehole and comprising:
• a transmitter configured to broadcast acoustic wave signals such that the acoustic wave signals interact with the cased-borehole;
• and a receiver configured to receive the acoustic wave signals;
• a processor;
• and
• a non-transitory computer-readable medium having instructions stored thereon that are executable by the processor to cause the system to:
• obtain acoustic cement bond evaluation data relating to a property of a cement bond of the cased-borehole for each of a plurality of acoustic methods by processing the received acoustic wave signals, wherein the acoustic cement bond evaluation data comprises a quality control (QC) value indicative of a confidence level of cement bonding conditions;
• determine an eccentricity value of the tubing relative to the casing in a borehole, wherein the eccentricity value provides a direction and a magnitude of the tubing relative to the casing, wherein the eccentricity value varies between 0% to 100%, wherein the eccentricity value 0% indicates that the tubing is centered in the casing, and wherein the eccentricity value 100% indicates that the tubing is touching a wall of the casing;
• determine an output of each acoustic method by combining the eccentricity value and the acoustic cement bond evaluation data associated with each of the acoustic methods;
• combine the output of each of the acoustic methods to generate an optimized cement bonding index log;
• and
• employ the optimized cement bonding index log to provide an interpretation of an overall cement bonding condition.

A well measurement system, comprising:

• an acoustic logging tool deployed in a cased-borehole in which a production tubing is installed within cement and casing, wherein the acoustic logging tool comprises:
• at least one transmitter configured to broadcast acoustic wave signals such that the acoustic wave signals interact with the cased-borehole;
• and
• at least one receiver configured to receive the acoustic wave signals;
• and
• an information handling system configured to:
• obtain acoustic cement bond evaluation data relating to a property of a cement bond for each of a plurality of acoustic methods by processing the received acoustic wave signals, wherein the acoustic cement bond evaluation data comprises a quality control (QC) value indicative of a confidence level of cement bonding conditions;
• determine an eccentricity value of the production tubing relative to the casing in the cased-borehole, wherein the eccentricity value provides a direction and a magnitude of the production tubing relative to the casing, wherein the eccentricity value varies between 0% to 100%, wherein the eccentricity value 0% indicates that the tubing is centered in the casing, and wherein the eccentricity value 100% indicates that the tubing is touching a wall of the casing;
• determine an output of each acoustic method by combining the eccentricity value and the acoustic cement bond evaluation data associated with each of the acoustic methods;
• combine the output of each of the acoustic methods to generate an optimized cement bonding index log;
• and
• employ the optimized cement bonding index log to provide an interpretation of an overall cement bonding condition.