Abstract: A system including a work string and an acoustic device for sensing or transmitting an acoustic signal at least partially traveling through a borehole fluid within a wellbore and a method of operation. The acoustic device includes a compensation fluid, an acoustic transducer at least partially disposed in the compensation fluid and configured to sense the acoustic signal, and a metallic cover that separates the compensation fluid from the borehole fluid and configured to deform in response to a pressure difference between the borehole fluid and the compensation fluid. The acoustic device is conveyed into the wellbore and an electric signal is sent or received with the processor to or from the acoustic transducer.

Abstract: A downhole tool can be deployed having an acoustic transducer array having a plurality of electroacoustic elements disposed circumferentially about the downhole tool, i.e., arrange in a circular shape. The acoustic transducer array can operate by activating active apertures to create synthesized acoustic pulses and receive the pulses' echoes, i.e., acoustic reflections, and then, in cooperation with one or more processors, create a 360° image of the casing and material behind the casing.

Abstract: This disclosure presents systems, methods, and apparatus for determining cluster efficiency during hydraulic fracturing, the method comprising: measuring acoustic vibrations in fracking fluid in a fracking wellhead, circulating fluid line, or standpipe of a well; converting the acoustic vibrations into an electrical signal in a time domain; recording the electrical signal to memory; analyzing the electrical signal in the time domain for a window of time and identifying two amplitude peaks corresponding to a fracture initiation; measuring a time between the two amplitude peaks; dividing the time by two to give a result; multiplying the result by a speed of sound in the fracking fluid to give a distance between the fracture initiation and a plug at an end of a current fracking stage of the well; and returning a location of the fracture initiation to an operator based on the distance between the fracture initiation and the plug.

Abstract: An integrated data recorder may be positioned within a slot in a tool. The integrated data recorder includes a sensor package that includes one or more drilling dynamics sensors, a processor in data communication with the one or more drilling dynamics sensors, a memory module in data communication with the one or more drilling dynamics sensors, a wireless communications module in data communication with the processor, and an electrical energy source in electrical communication with the memory module, the one or more drilling dynamics sensors, and the processor.

Abstract: An apparatus for inspecting a well having nested multi-tubular structure, includes: an acoustic transducer conveyed in an inner-most tubular in the structure and configured to receive a return acoustic signal having a plurality of resonances due to the structure; an acoustic impedance matching material disposed on a sensing face of the acoustic transducer; a signal generator that generates a signal having a plurality of frequencies to drive the acoustic transducer; a signal shaper that modifies the signal to provide a drive signal to the acoustic transducer; and a processor configured to determine an annulus distance of any tubular in the structure with respect to an adjacent tubular using a time of flight of a transmitted acoustic signal, an acoustic speed in a component in the nested multi-tubular structure using the annulus distance and the plurality of resonances, and a characteristic of the component that corresponds with the acoustic speed.

Abstract: A method and a system to determine fracture properties during standard operations and injection tests. Fracture compliance, fracture closure pressure, and perforation friction can be determined using a combination of acoustic data, pressure decay data, and wellbore models. A method of automating and adjusting fracture design in real-time. A method and system to recover active, single active pulse data from a background noise dataset.

Abstract: A system for controlling a flow of fluid includes a flow control device having a fluid channel configured to transport a fluid between a subterranean region and a borehole conduit, a resonant sensing assembly including a resonator body disposed in fluid communication with the fluid channel, and a controller configured to cause the resonator body to vibrate according to an expected resonance frequency of the resonator body. The system also includes a processing device configured to acquire a measurement signal generated by the resonator body, estimate a property of the fluid based on the measurement signal, and control a flow of the fluid through the flow control device based on the property of the fluid.

Abstract: A wireless sensor network (WSN) includes a sensor node cluster having a plurality of sensor nodes positioned along a section of a pipeline; a base station; a designated cluster head for the sensor node cluster, the designated cluster head configured to forward sensor data packets towards the base station; and a server having circuitry. The circuitry is configured to determine when the designated cluster head has a battery energy level below a predetermined level, elect a replacement cluster head for the designated cluster head when the battery energy level is below the predetermined level, and forward an energy status of the designated cluster head to the replacement cluster head.

Abstract: A gas concentration measurement device comprises: a transmission circuit and a transmission oscillator for transmitting first ultrasonic waves in a concentration measurement space and transmitting second ultrasonic waves, which continue temporally from the first ultrasonic waves in the concentration measurement space; a reception oscillator and a reception circuit for receiving the ultrasonic waves that have propagated through the concentration measurement space; and a propagation time measurement unit for determining, on the basis of the times at which the first ultrasonic waves and the second ultrasonic waves were transmitted and the times at which the first ultrasonic waves and the second ultrasonic waves were received, the time in which ultrasonic waves propagate through the concentration measurement space.

Abstract: Methods and systems for characterizing fractures in a subterranean formation are provided. The method includes introducing an encapsulated explosive unit into a casing located in a wellbore within the subterranean formation and maintaining the encapsulated explosive unit in a stage of the casing. The method also includes detonating the encapsulated explosive unit within the stage to generate a pressure wave that passes through a group of perforations and into the fractures and measuring a reflected pressure wave using a pressure sensor coupled to the bridge plug to produce a pressure measurement. The method further includes converting the pressure measurement into an acoustic signal correlated with the pressure measurement by an acoustic signal generator contained in the bridge plug and transmitting the acoustic signal to apply acoustic pressure on a fiber optic cable coupled to an exterior surface of the casing.

Abstract: A system and method for determining fluid inflow into a wellbore. The system may include a drill string including an earth-boring tool. The drill string may further include a first array of sensors arranged radially about the drill string in a region of the drill string after the earth-boring tool. The drill string may be configured to be inserted into the wellbore and the first array of sensors may be configured to detect an inflow of fluid into the wellbore through a change in an environmental property of the wellbore.

Abstract: A depth monitoring and valve lockout automatically resists operation of a valve when a wireline is being used within a well. The system utilizes components which can be attached to presently available wellheads, wireline lubricators, and accumulators without modification. A wellhead unit detects a beacon secured to a wireline lubricator to determine the wellhead for which the lubricator is being used. Proximity sensors detect proximity indicators secured to the wireline reel to detect rotation of the reel. Rotation of the reel is used to determine the presence of wireline within the wellhead having the wireline lubricator. An accumulator unit actuates linear actuators to move the presently existing lockout controls in response to the presence or removal of the wireline.

Abstract: A strain and acoustic wave testing device includes an acoustic wave transmitting terminal, an upper pressure-bearing shaft, corundum ejector pins, an upper displacement slide, a lower displacement slide, a heat insulation shell, a carbon fiber sleeve, a rock sample, a lower pressure-bearing shaft, an acoustic wave receiving terminal, a lower copper electrode, pearl powder, a temperature sensor, a transformer, a temperature-acoustic wave control box, an oscilloscope, an upper copper electrode, and a data collection and processing system.

Abstract: Methods and apparatus pertaining to determining shape and size of a borehole at a depth within a subterranean formation using ultrasonic measurements obtained by a downhole tool at four different azimuthal locations corresponding to four mutually orthogonal directions extending radially from a central axis of the downhole tool. The measurements are indicative of a distance between a wall of the borehole and the downhole tool at each azimuthal location. The borehole shape and size are determined by estimating an ellipse approximating the borehole shape and size using the ultrasonic measurements.

Abstract: An optical touch apparatus includes a light source unit, an optical signal processing unit, and a position computation unit. The light source unit emits light beams and generates three reference light spots at different positions. The optical signal processing unit receives three pieces of reflected light information respectively reflected and propagated by the three reference light spots and analyzes the three pieces of reflected light information to correspondingly generate three pieces of optical analysis information, each of the three pieces of optical analysis information includes a piece of vibration wave information and a piece of vibration time point information, and the piece of vibration wave information includes a touch vibration wave. The position computation unit computes a piece of touch position information according to each of the pieces of light spot position information, each of the pieces of vibration time point information, and the piece of vibration wave velocity information.

Abstract: A method includes introducing a tool string into a wellbore having material disposed in an annular region surrounding the casing. Obtaining acoustic refracted waveform measurements of the material from a cement bond logging tool, obtaining ultrasonic measurements of the material from a circumferential acoustic scanning tool, obtaining gamma radiation measurements scattered from the material from a circumferential spectral density logging (RSDX) tool by emitting gamma radiation from a radioactive source in a rotating portion of the RSDX and detecting scattered gamma radiation using near and far spectral density detectors, and obtaining thermal neutron radiation measurements scattered from the material from a dual spaced neutron logging tool. A computer obtains measurements and generates a deliverable that includes one or more cross plots that identify a compositional equivalent of the material in an entire circumference of the wellbore.

Abstract: A fiber optic termination sealingly connects to a cable which includes a casing having a cable tube and optical fibers. The termination includes a sealed housing, a manifold, a connector and termination tubes. The housing has an inlet to sealably receive the cable. The fibers extend from an end of the cable into a sealed chamber of the housing. The manifold is positionable in the housing, and has an inlet to receive the fibers and sealed passages shaped to distribute the fibers therethrough the connector includes contacts communicatively connectable to equipment and the fibers. The termination tubes are positionable within the chamber of housing, and have an entry end sealingly connectable to an end of the cable tube and a contact end sealingly connectable to the contacts.

Abstract: A flow imaging and monitoring system for synchronized management of wide area drainage that includes an interposer for supporting monitoring and management equipment in a manhole, a module for illuminating water flowing in pipes at the base of the manhole, a module for monitoring responses to reflected light, a sealed and rechargeable battery pack, and a data analysis and management system to interpret data streams in real time. The interposer can be adjusted to fit the diameter of the manhole and can be adjusted to be placed under the manhole cover. The module for illuminating the flowing water can be adjusted to generate various frequencies. The support structures for the modules can be adjusted for varying pitch, roll and yaw with respect to the manhole. The data analysis and management system is supported by cloud computing.

Abstract: A technique facilitates geophysical exploration and comprises deploying an optical fiber in a borehole formed in a formation. A seismic signal, e.g. seismic waves, is excited into the formation, and an optical interrogation system is used to obtain data at a plurality of fixed, sampling locations along the optical fiber. The data is processed to determine features in the formation. Based on the processed data, updated sampling locations are selected along the optical fiber to enable further analysis of the features of interest.

Abstract: A distance of a water flow path and a velocity of the water flow is calculated using data obtained from both a pulsed neutron sensor and distributed acoustic sensors. The two distance and velocity values are compared to obtain a first calculated distance and velocity. The distance of the water flow path and the velocity of the water flow are calculated using the Doppler data obtained from distributed Doppler sensors. The distance and velocity values are compared with the first calculated distance and first calculated velocity to obtain a second calculated distance and velocity values. The distance of the water flow path and the velocity of the water flow are calculated using temperature data obtained from distributed temperature sensors. The distance and velocity values are compared with the second calculated distance and velocity to determine a distance of a cement interface, and a velocity of a water flow therein.

Abstract: A distance of a water flow path and a velocity of the water flow is calculated using pulsed neutron data and noise data. The two distance and velocity values are compared with each other to obtain a first calculated distance and a first calculated velocity. The distance of the water flow path and the velocity of the water flow are calculated using Doppler data. The distance and velocity values are compared with the first calculated distance and first calculated velocity to obtain a second calculated distance and velocity values. The distance of the water flow path and the velocity of the water flow are calculated using temperature data. The distance and velocity values are compared with the second calculated distance and velocity to determine a distance of a cement interface and a velocity of a water flow in the cement interface.

Abstract: A distance of a gas flow path and a velocity of the gas flow therein are calculated using pulsed neutron data and noise data. The gas saturation and distance to flow path obtained from the pulsed neutron data and gas velocity and distance to flow path obtained from the noise data are compared with each other to obtain a first calculated distance and a first calculated velocity. The distance and the velocity of the gas flow are calculated using Doppler data. The distance and velocity values are compared with the first calculated distance and first calculated velocity to obtain a second calculated distance and velocity values. The distance and the velocity of the gas flow are calculated using temperature data. The distance and velocity values are compared with the second calculated distance and velocity to determine a distance of a cement interface and a velocity of a gas flow therein.

Abstract: A flow imaging and monitoring system for synchronized management of wide area drainage that includes an interposer for supporting monitoring and management equipment in a manhole, a module for illuminating water flowing in pipes at the base of the manhole, a module for monitoring responses to reflected light, a sealed and rechargeable battery pack, and a data analysis and management system to interpret data streams in real time. The interposer can be adjusted to fit the diameter of the manhole and can be adjusted to be placed under the manhole cover. The module for illuminating the flowing water can be adjusted to generate various frequencies. The support structures for the modules can be adjusted for varying pitch, roll and yaw with respect to the manhole. The data analysis and management system is supported by cloud computing.

Abstract: Methods, systems and acoustic tags for tracking, locating and identifying an object are disclosed. An acoustic tag may include a power source and a transmitter in electrical communication with the power source. The transmitter may be configured to transmit an acoustic signal. The power source and the transmitter may be configured to be affixed to and/or embedded in an electronic component. The acoustic signal may include a unique acoustic code that is configured to provide information pertaining to one or more of the electronic component and the recyclability of the electronic component.

Abstract: While an insert shaft (11) disposed with a wide angle lens (15) at a top end thereof is being inserted into a hole to inspect a wall surface of the hole on the basis of an image photographed through the wide angle lens (15), gas is injected into the innermost recess of the hole along the outer circumferential surface of the insert shaft (11) by a gas injection mechanism (19). The gas injection mechanism (19) is provided with a guide (13) configured to surround a top end portion of the insert shaft (11) and form a gas injection passage (R) extending in the longitudinal direction of the insert shaft (11) between the inner circumferential surface of the guide (13) and the outer circumferential surface of the insert shaft (11), and a gas supply unit (14c) configured to supply gas to an inner space of the guide (13).

Abstract: An ultrasonic transducer includes a wear plate (2), a piezoelectric element (8) arranged rearwards of the wear plate and a rigid block (16) arranged rearwards of the piezoelectric element and configured to provide a backing mass for the piezoelectric element. The wear plate extends across the piezoelectric element and rearwards so as to provide a cap over the piezoelectric element and sides of at least a forward portion of the rigid block.

Abstract: A dipole source for borehole acoustic logging is provided, including a cylindrical shell, a center beam coupled to the cylindrical shell and a movable projector inside the cylindrical shell to impact the center beam. The dipole source includes a cavity acoustically insulating the interior of the cylindrical shell from the exterior of the cylindrical shell. An acoustic logging tool for making measurements of a substrate surrounding a borehole with a body insertable in the borehole is also provided. The body includes an acoustic detector and a dipole source as above, along the axial length. The acoustic logging tool may include a control unit to process data collected from the acoustic detector and obtain information about the substrate surrounding the borehole. According to embodiments disclosed herein, a method for operating a dipole source and an acoustic logging tool as above is provided.

Abstract: A parking sensor device has a casing, a front cover, a sensor module and an assembling clamp. The casing has two first hooking elements. The front cover is mounted on the casing. The sensor module is mounted in the casing and the front cover. The assembling clamp detachably engages the casing and has two second hooking elements. The second hooking elements selectively hook the first hooking elements of the casing respectively. The casing and the assembling clamp are engaged quickly with each other, thereby facilitating the easy fabrication of the parking sensor device and improving the convenience of maintenance of the parking sensor device.

Abstract: The combination of one or more 3-component microseismic sensors deployed into a wellbore adjacent a microseismic event and a linear array of distributed fiber optic acoustic sensors deployed uphole thereof provides two sets of data for establishing noise-free signals for locating the microseismic event in the formation about the wellbore. The distributed fiber optic signals monitor noise transmitted along coiled tubing used to pump a completion operation or as a result of the fluid flowing through the casing or coiled tubing, or along wireline used to deploy the microseismic sensors. The noise is mapped and extrapolated for estimating noise at the 3-component sensors. The estimated noise is removed from the 3-component sensor data for producing clean signals representing the location of the microseismic events.

Abstract: An apparatus for monitoring vibration of a downhole component includes an optical fiber sensor including at least one optical fiber operably connected to an interrogation unit. The at least one optical fiber has a resonant segment that is fixedly attached to the component via attachment points on the component, the resonant segment between the attachment points being separate from the component and having a resonant frequency based at least on the length of the resonant segment.

Abstract: An acoustic sensing system includes, an optical fiber, a plurality of pairs of reflectors distributed along the optical fiber at specific areas where acoustic energy data is sought, a source of coherent radiation in operable communication with the optical fiber, and a detector in operable communication with the optical fiber configured to detect a different wavelength of coherent radiation reflected from each of the plurality of pairs of reflectors including a portion of the coherent radiation reflected from the reflector nearer the detector after having reflected from the reflector further from the detector that define one of the pairs of reflectors.

Abstract: A non-contact signal propagation property evaluation system for ropes can be deployed for a number of different applications including, but not limited to, moving lines, e.g., crane or winch and static lines, e.g., mooring lines, stays, etc., to evaluate physical properties of the ropes and, in some cases, to help evaluate structural health of the ropes. The system includes a first transducer for generating ultrasonic waves, a second transducer for receiving ultrasonic waves propagated transversely through and around the rope, and a processor executing computer readable code to determine acoustic propagation properties of the rope.

Abstract: An apparatus having a transducer configured to generate acoustic energy, a buffer rod with a first end and a second end, the transducer in contact with the first end, a cylinder configured to define a volume, the second end of the buffer rod abutting the cylinder; and a piston within the cylinder.

Abstract: A method for measuring the deformation of elastomeric materials using acoustic signals involves obtaining a sample, positioning the sample in a sealable chamber, sealing the chamber, and setting a temperature and pressure inside the chamber. A test fluid may be introduced to the chamber. An acoustic signal is used to measure a characteristic of the sample, such as a dimension or a modulus. Repeated measurements may be made overtime to monitor changes in the sample in response to temperature and pressure. The acoustic signal may be generated by an acoustic transducer including a backing component including a fluorine-containing polymer in which metal particles are incorporated. The sample may be a non-metallic material. Conditions inside the chamber may be set to simulate a wellbore environment.

Abstract: Provided is a device for predicting an underground behavior by using an acoustic emission (AE) sensor, including: a waveguide rod having an elongated end to be inserted in a borehole; a plurality of acoustic emission sensors mounted on different positions of the waveguide rod; a wrapping layer configured to cover a circumferential surface of the waveguide rod such that a gap is formed between the waveguide rod and the wrapping layer; an acoustic emission generating layer filled into the gap and being homogeneous along a direction of the waveguide rod; and a grouting layer configured to fix the waveguide rod in the borehole.

Abstract: A sensor pod housing assembly for placement within a borehole includes a housing, a selectively operable first hydraulic actuator supported by the housing and adapted to act in a first direction and a selectively operable second hydraulic actuator supported by the housing and adapted to act in a second direction which is substantially parallel to and opposite the first direction. The sensor pod housing assembly further includes a sensor pod adapted to contact a wall of the borehole when deployed to substantially immobilize the sensor pod relative to the borehole. A first substantially rigid link pivotally connects the first hydraulic actuator and the sensor pod, and a second substantially rigid link pivotally connects the second hydraulic actuator and the sensor pod.

Abstract: A system and method of monitoring a pressure, temperature, and/or vibration of a hostile environment without requiring the use of active electronics or an oscillator circuit in that environment. The system and method interrogate a resonant pressure sensor and a resonant or passive temperature sensor connected to a transmission line and located at least 100 feet (30.48 m) away from a network analyzer. The system and method use the reflected frequencies from the sensors to determine the pressure, temperature, and/or vibration. If the sensors are networked by the transmission line or a network filter, the reflected portion can include the reflected transmission energy. The applied signal and reflected portion travel along the transmission line, which is preferably impedance matched to that of the system. If a multi-conductor cable is used, the effects of the cable's length and temperature are compensated for via a system calibration when in field use.

Abstract: A sensing subassembly for use with a downhole tool comprises a housing, a cavity disposed within the housing, at least one electronic component disposed within the cavity, and at least one isolating member disposed within the cavity. The at least one isolating member is configured to attenuate at least a portion of frequency components of a mechanical wave above a threshold and transmit at least a portion of frequency components below the threshold to the at least one electronic device.

Abstract: A sensing subassembly for use with a downhole tool comprises a housing, a cavity disposed within the housing, an electronic board disposed within the cavity, a stiffening member engaging the electronic board and configured to limit flexing of the electronic board, and a spring member configured to provide an isolation mount for the electronic board within the cavity.

Abstract: In an embodiment, a sensing subassembly for use with a downhole tool comprises a housing, a cavity extending into the housing, a sensor disposed at least partially within the cavity, a shock mitigating member disposed between at least one end of the sensor and the housing, and at least one seal member disposed between the sensor and the housing. At least a portion of the sensor is in fluid communication with an exterior of the housing, and the shock mitigating member is configured to attenuate at least a portion of a shock wave between the housing and the sensor.

Abstract: A pneumatic vibration isolating suspension is disclosed for supporting a payload on a moving carrier while suppressing the transmission of vibrations in the 1 to 50 Hz band between the carrier and the payload. The disclosed invention can be deployed in the air in a towed carrier or sonde, and operated from aircraft power, making it a suitable platform for airborne geophysical instrumentation. It also has particular application to airborne electromagnetic surveying operating in the same frequency band because the sensor vibrations that result in noise created by the modulation of the sensor coupling with the earth's magnetic field are suppressed. Furthermore, the invention can be constructed from resistive composite materials and non-magnetic metals, so it can be operated without producing significant modification to the ambient electromagnetic field being measured.

Abstract: A method and apparatus for determining the relative orientation of objects downwell, and especially to determining perforator orientation, involves varying the orientation of an object, such as a perforator gun (302) in the wellbore (202) and activating at least one directional acoustic source (402a-c). Each directional acoustic source is fixed in a predetermined location to the object and transmits an acoustic signal preferentially in a known direction. The directional acoustic sources are activated so as to generate sound in a plurality of different orientations of said object. An optical fibre (104) is interrogated to provide distributed acoustic sensing in the vicinity of the object; and the acoustic signals detected by the optical fibre are analysed to determine the orientation of the at least one directional acoustic source relative to the optical fibre, for instance by looking at the relative intensity in the different orientations.

Abstract: The present invention relates to a downhole tool (1) for determining laterals in a borehole wall (3) or a borehole casing (4), comprising a tool housing (5) extending along a longitudinal axis (6) and having a circumference perpendicular to the longitudinal axis and adapted to be lowered into a well, and a plurality of sonic transceivers (7), each sonic transceiver transmitting sonic signals (8) from the housing and receiving sonic signals reflected from the borehole wall or borehole casing in a pre-defined angular segment (9), wherein the plurality of sonic transceivers are arranged along the circumference of the tool housing having a mutual distance and are capable of transmitting sonic signals radially away from the tool housing in an entire central angle of 360 degrees towards the borehole wall or borehole casing and wherein, during use, one sonic transceiver, during a pulse time, transmits a sonic signal in the predefined angular segment of that sonic transmitter, and wherein one sonic transceiver, durin

Abstract: An apparatus for estimating at least one of a dynamic motion of a portion of interest of a drill string and a static parameter associated with the portion of interest, the apparatus having: a plurality of sensors operatively associated with the drill string at at least one location other than the portion of interest; and a processing system coupled to the plurality of sensors, the processing system configured to estimate at least one of the dynamic motion and the static parameter using a measurement from the plurality of sensors as input.

Abstract: A method of calibrating a distributed acoustic sensing system can include receiving predetermined acoustic signals along acoustic sensors distributed proximate a well, and calibrating the system based on the received acoustic signals. A method of calibrating an optical distributed acoustic sensing system can include displacing an acoustic source along an optical waveguide positioned proximate a well, transmitting predetermined acoustic signals from the acoustic source, receiving the acoustic signals with the waveguide, and calibrating the system based on the received acoustic signals. A well system can include a distributed acoustic sensing system including an optical waveguide installed in a well, and a backscattered light detection and analysis device, and at least one acoustic source which transmits predetermined acoustic signals at spaced apart locations along the waveguide. The device compensates an output of the system based on the acoustic signals as received at the locations along the waveguide.

Abstract: Devices and methods for borehole seismic investigation. The devices can include a first sensor for acquiring data relating to a microseismic event, a second sensor for detecting the start of a microseismic event and a command module for activating the first sensor to transmit data when the second sensor detects the start of the microseismic event. The methods can include activating a first sensor to transmit data relating to a microseismic event when a second sensor detects the start of the microseismic event. The method can also include deactivating the first sensor, or stopping data transmission substantially when the microseismic event ends.

Abstract: A transducer for use with a downhole tool, where the transducer includes concentric piezoelectric elements coupled with a member that extends from the top surface of one element to the bottom surface of another element. The elements expand and contract to vibrate by applying electrical potential to the elements. The element having the member on its bottom surface expands and contracts with applied electrical potential and also is urged upward, by the coupling member, an amount equal to the vertical displacement of the element having the member on its top surface. Thus the element having the member on its bottom surface is vertically displaced by an amount substantially equal to the expansion of the elements.

Abstract: Disclosed is a method for estimating downhole lateral vibrations a drill tubular disposed in a borehole penetrating the earth or a component coupled to the drill tubular. The method includes rotating the drill tubular to drill the first borehole and performing a plurality of measurements in a time window of one or more parameters of the drill tubular at or above a surface of the earth during the rotating using a sensor. The method further includes estimating the downhole lateral vibrations using a processor that receives the plurality of measurements.

Abstract: The invention provides a system for leak detection of a fluid in a pipe network. The system includes flow meters, and vibration detectors adapted to be attached to a pipe at a location in the pipe network. A processor analyzes signals generated by the flow meters and vibration detectors to identify the presence of one or more leaks in the pipe network. The invention also provides a method for detecting and localizing leaks in a pipeline network, and a device comprising a flow meter integral with a vibration detector for use in the system of the invention.

Abstract: A method for monitoring fluid flow through a downhole device, comprises a) providing an acoustic tube wave in fluid in the device; b) measuring the acoustic tube wave after it has passed through the fluid in the device; and c) assessing the permeability of the device by measuring the attenuation of the acoustic signal. Changes in velocity of the acoustic signal may also be measured. The device may be a permeable downhole device such as a sand screen the measurements in step b) are made using a plurality of sensors deployed in the hole. The method may further including the step of cross-correlating a signal received at a first receiver with signals received at additional sensors so as to obtain an effective response as if the signal had been emitted from a source at the position of said first receiver.