Abstract: According to embodiments of the disclosure, a downhole tool for taking acoustic measurements in a wellbore is provided. The tool may have an acoustic dipole transmitter with a piston made from a soft magnetic material, mounted on a centering spring between the first coil and the second coil, which moves the piston bi-directionally along a longitudinal axis when energized. The tool may also have a feedback winding on at least one of the first or second coils. The tool may also have a circuit for energizing the first and second coils which includes an input for receiving a signal responsive to the position of the piston relative to the coils and a processor for determining an output waveform used to generate an acoustic signal.

Abstract: According to embodiments of the disclosure, a downhole tool for taking acoustic measurements in a wellbore is provided. The tool may have an acoustic dipole transmitter with a piston made from a soft magnetic material, mounted on a centering spring between the first coil and the second coil, which moves the piston bi-directionally along a longitudinal axis when energized. The tool may also have a feedback winding on at least one of the first or second coils. The tool may also have a circuit for energizing the first and second coils which includes an input for receiving a signal responsive to the position of the piston relative to the coils and a processor for determining an output waveform used to generate an acoustic signal.

Abstract: An attenuation apparatus, system, and method are disclosed. The attenuator is attached to a pipe and includes a housing that includes an inner sleeve and an outer sleeve. The attenuator includes one or more masses, to resonate when exposed to waves including acoustic frequency components.

Abstract: An acoustic logging tool including an elongated body, one or more acoustic transmitters, one or more acoustic receivers, and a broadband acoustic absorption region. A substantial portion of the broadband acoustic absorption region is between the transmitter and the receiver. The acoustic energy absorber includes a first absorber for absorbing a first mode of acoustic energy and a second absorber for absorbing a second mode of acoustic energy. The acoustic absorption material used to make the acoustic absorbers has an acoustic impedance between 20% and 120% of the material used to construct the acoustic logging tool. The acoustic logging tool includes an elongated hollow tool body, an insert configured to be inserted into the tool body, and a ring configured to be inserted onto the insert. A first element is supported by the ring and exposed to a pressure field, and a second element is supported by the ring and exposed to a pressure field.

Abstract: An acoustic logging tool including an elongated body, one or more acoustic transmitters, one or more acoustic receivers, and a broadband acoustic absorption region. A substantial portion of the broadband acoustic absorption region is between the transmitter and the receiver. The acoustic energy absorber includes a first absorber for absorbing a first mode of acoustic energy and a second absorber for absorbing a second mode of acoustic energy. The acoustic absorption material used to make the acoustic absorbers has an acoustic impedance between 20% and 120% of the material used to construct the acoustic logging tool. The acoustic logging tool includes an elongated hollow tool body, an insert configured to be inserted into the tool body, and a ring configured to be inserted onto the insert. A first element is supported by the ring and exposed to a pressure field, and a second element is supported by the ring and exposed to a pressure field.

Abstract: An acoustic logging tool including an elongated body, one or more acoustic transmitters, one or more acoustic receivers, and a broadband acoustic absorption region. A substantial portion of the broadband acoustic absorption region is between the transmitter and the receiver. The acoustic energy absorber includes a first absorber for absorbing a first mode of acoustic energy and a second absorber for absorbing a second mode of acoustic energy. The acoustic absorption material used to make the acoustic absorbers has an acoustic impedance between 20% and 120% of the material used to construct the acoustic logging tool. The acoustic logging tool includes an elongated hollow tool body, an insert configured to be inserted into the tool body, and a ring configured to be inserted onto the insert. A first element is supported by the ring and exposed to a pressure field, and a second element is supported by the ring and exposed to a pressure field.