An apparatus and system for deploying an acoustic sensor are disclosed. In some embodiments, an acoustic sensor includes a transducer comprising a piezoelectric material layer having a front side from which the transducer is configured to transmit acoustic sensing signals and an opposing back side. A backing material layer comprising an acoustic damping material is coupled at a front side to the back side of the piezoelectric material layer. An acoustic reflector such as may comprise a cavity containing gaseous or liquid fluid is disposed between the front side and a back side of the backing material layer.

A well tool for sensing seismic activity at a downhole location has an anchoring mechanism for mechanically coupling the tool to a formation by contact engagement with a wall of a subterranean cavity in which the well tool is located. The anchoring mechanism is deployable by a pressure-triggered hydraulic actuator incorporated in the tool. The actuator is configured for pressure-triggered activation and for hydraulic actuation by agency of borehole fluids (e.g., drilling mud). The actuator can provide a persistent contacting force urging the anchoring mechanism into contact with the cavity wall, to promote firm coupling with the formation for seismic sensoring purposes.

Methods, systems, devices, and products for ultrasonic borehole logging using an ultrasonic borehole imaging tool in a borehole intersecting the earth formation. Methods may include adjusting a focus for an ultrasonic beam generated from a single-transducer ultrasonic assembly of the ultrasonic imaging tool; using a receiver to generate measurement information responsive to an ultrasonic signal caused by the ultrasonic beam; and estimating a parameter of interest from the measurement information. Methods may include adjusting the focus in dependence upon environmental conditions, the environmental conditions comprising at least one of: i) standoff between the ultrasonic imaging tool and a wall of the borehole; and ii) borehole annulus conditions. Methods may include adjusting the focus in substantially real-time. The ultrasonic beam may be focused with a focal zone at the borehole wall configured to produce a beam spot size of a selected diameter.

A system includes a first instrumented bridge plug positionable in a downhole wellbore environment. The first instrumented bridge plug includes an acoustic source for transmitting an acoustic signal. The system also includes a second instrumented bridge plug positionable in the downhole wellbore environment. The second instrumented bridge plug includes an acoustic sensor for receiving a reflected acoustic signal originating from the acoustic signal. The reflected acoustic signal being usable to interpret wellbore formation characteristics of the downhole wellbore environment.

A downhole device for installation in a petroleum well, comprising a sensor, a controller and a power source. The device further comprises an acoustic speaker configured to output a sound signal from the downhole device to a fiber optic cable in the well.

A method of imaging a wellbore casing using an ultrasonic sensing system through the material of a drill string as the drill string is tripped out of the wellbore.

A Transducer in a downhole environment with an increased amplitude of the transducer output at lower frequencies. A transducer may include a bender bar, wherein the bender bar may include a first piezoelectric layer disposed on one surface of the bender bar, a second piezoelectric layer disposed on the opposite surface of the bender bar, and a metallic substrate disposed between the first piezoelectric layer and the second piezoelectric layer. The transducer may further include a first fixed end is attached to the bender bar and connects the bender bar to a base, a second fixed end opposite the first fixed end that attaches the bender bar to the base, and a compartment disposed within the base.

Disclosed is an acoustic sensor system comprising an electrical connector, at least one transducer connected to the electrical connector, a fluid compensating piston connected to the electrical connector, a housing having the electrical connector, the at least one transducer, and the fluid compensating piston arranged in a linear arrangement, and a collar having the housing mounted along an interior surface of the collar.

An apparatus for use in acoustically assessing a wellbore, comprises a tubular body, an acoustic transmitter supported on the body, first and second acoustic receivers supported on the body with the second receiver being farther from the transmitter, wherein at least one of the inner and outer body surfaces includes a helical groove between the acoustic transmitter and the first acoustic receiver and the helical groove is filled with a composite material. The body may include a second helical groove that has the same pitch as the first helical groove and is diametrically opposite the first helical groove and may further include a third helical groove between the first and second receivers. At least one of the grooves may an opening width that is less than the maximum groove width and may have a cross-sectional area that includes a neck. The composite material may comprise tungsten particles in rubber.

Example ultrasonic transducers for measuring formation velocities are disclosed herein. An example apparatus includes a housing and an acoustic transducer having a first surface and a second surface opposite the first surface. The acoustic transducer is at least partially disposed in the housing. The example apparatus includes a window supported by the housing. At least a portion of the first surface of the acoustic transducer is in contact with the window. The housing and the window are to form a fluid seal for the acoustic transducer.