A system for determining a location and a diameter of a pipe deployed in a bore includes a plurality of circumferentially spaced acoustic transmitters and a plurality of circumferentially spaced acoustic receivers deployed in a wall of the bore. A processor is configured to identify and process received acoustic waveforms that are reflected by the pipe to compute the location and the diameter of the pipe. The system may include a drill string deployed in a drilling riser.

A technique facilitates use of acoustic measurements to enable geo-steering during a well operation. A steerable well string is provided with acoustic systems used to collect data which is then processed to determine geo-steering inputs. In some applications, the well string may comprise a coiled tubing drilling tool. The coiled tubing drilling tool or other well string tool is combined with an azimuthally distributed pitch-catch micro-sonic sensor system and an azimuthally distributed ultrasonic pulse-echo transducer system. Data from these two systems is provided to a processing system which processes the data to determine, for example, real-time, geo-steering inputs. These inputs may then be used to more effectively steer the coiled tubing drilling tool or other well string tool.

A well-logging tool may include a sonde housing and a radiation generator carried by the sonde housing. The radiation generator may include a generator housing, a target carried by the generator housing, a charged particle source carried by the generator housing to direct charged particles at the target, and at least one voltage source coupled to the charged particle source. The at least one voltage source may include a voltage ladder comprising a plurality of voltage multiplication stages coupled in a uni-polar configuration, and at least one loading coil coupled at at least one intermediate position along the voltage ladder. The well-logging tool may further include at least one radiation detector carried by the sonde housing.

A pipe inspection tool includes a body having a central axis, and one or more azimuthal antenna arrays operatively coupled to the body. Each azimuthal antenna array includes a plurality of antenna coils arranged circumferentially about the central axis and comprising an azimuthal array of z-coils or an azimuthal array of separated x-coils and separated y-coils. The separated x-coils are oriented in a first direction with respect to the central axis, the separated y-coils are oriented in a second direction with respect to the central axis, and the z-coils are oriented in a third direction with respect to the central axis. The second direction is orthogonal to the first direction, and the third direction is orthogonal to both the first and second directions.

In accordance with embodiments of the present disclosure, systems and methods for improving performance of ultrasonic transducers, particularly those used in borehole environments, are provided. The disclosed ultrasonic transducers all feature a backing element that is a ceramic backing material. The ceramic backing material may include a solid piece of ceramic material that is disposed on a back end of a piezoelectric element used in the ultrasonic transducer. The disclosed ceramic backing material may be used to mechanically match the backing element to the piezoelectric source element, while minimizing the amplitude of reflections of the ultrasonic pulse generated by the piezoelectric element and reflected at the far end of the backing element. This ceramic backing material may provide consistent performance regardless of the surrounding pressure and temperature, making it particularly useful in borehole applications.

A method comprising: conveying a downhole tool in a tubing that is positioned in a casing that is positioned to form an annulus between the casing and a wall of a wellbore formed in a subsurface formation, wherein a cement with unknown bonding condition exists in the annulus, wherein the downhole tool includes at least one transmitter and a receiver array physically positioned in different azimuthal directions; emitting, from the at least one transmitter, a first and second acoustic transmissions in a first and second azimuthal directions; detecting, by the receiver array, a first acoustic response and a second acoustic response that is derived from the first and second acoustic transmissions, wherein the second azimuthal direction is orthogonal to the first azimuthal direction; determining a dipole wellbore resonance based on the first and acoustic responses; and evaluating a property of the cement based on the dipole wellbore resonance.

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.

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.

An example method includes determining a frequency response of a tuned pulse to be transmitted from a transmission element. A matching frequency envelope corresponding to a frequency envelope of the frequency response may be determined. A time domain signal corresponding to the matching frequency envelope may be determined. A series of digital pulses corresponding to the time domain signal may be determined. An analog output at a switching amplifier corresponding to the series of digital pulses may be generated. A transmission element may be excited with the analog output.

An apparatus for measuring environmental parameters along a drill string includes a protector disposed radially around the drill string, and a sensor system with an optical fiber configured to collect data on environmentalditions within a wellbore through which the drill string is being inserted. Protector is made of a composite material having the sensor system and the optical fiber embedded within. Collected data may be extracted from the sensor system. A method of collecting data on environmental conditions within a wellbore includes disposing a sensor system onto a matrix substrate of a protector; coating the sensor system and matrix substrate with a composite material; curing the composite material so as to embed the sensor system within the protector; forming a protector around a drill string; using the sensor system to collect data from within the wellbore upon insertion of the drill string and protector; and retrieving the collected data.