Abstract: An acoustic transceiver assembly including a housing, an oscillator, and at least one membrane. The housing has at least one inner wall defining a cavity. The housing also has a first end and a second end defining an axis of the acoustic transceiver assembly. The oscillator is provided in the cavity. The oscillator is provided with a transducer element, and a backing mass acoustically coupled to the transducer element. The at least one membrane extends outward from the backing mass to support at least the backing mass within the cavity. The at least one membrane is flexible in an axial direction parallel to the axis of the acoustic transceiver assembly to permit the backing mass to oscillate in the axial direction, and rigid in a transverse direction to restrict lateral movement of the backing mass relative to the housing.

Abstract: A telemetry system produces, transmits and receives signal sets from network nodes, which correspond to transceiver stations. Repeater scheduling and other interference mitigating techniques are utilized to simultaneously transmit from multiple nodes with minimized network degradation. Update interval/rate and network throughput are thereby fixed regardless of the number of network nodes and a network telemetry method is provided using the system.

Abstract: A robust network telemetry repeater system exploits the repeater structure of data propagation and transmission and reception bi-directionality to increase network robustness. For example, multiple perceived receive attempts are created with no additional overhead. The system can be configured whereby nodes “hear” the transmissions of both adjacent and non-adjacent nodes forming implicit acknowledgement (“Acks”), and originating nodes can retransmit until implicit acknowledgments (“Acks”) are “heard,” indicating a successful link relay. Implicit acknowledgment can be applied to bidirectional networks, and bidirectional action can enable all nodes in the network to know the status of all other nodes.

Abstract: Pressure measurements are made using a pressure sensor in the proximity of the drillbit during drilling operations. A filtered version of the pressure measurements is provided to a pulser for a mud-pulse telemetry system so as to cancel pressure variations due to drilling noise while a telemetry signal is being sent. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: A disclosed acoustic telemetry system includes a downhole acoustic telemetry module that generates an acoustic uplink signal such as a pulsed fluid flow or compressional waves in a tubing string wall. An optical waveguide transports an optical signal representing the acoustic uplink signal to the surface interface. A related telemetry method includes acquiring measurements downhole, transmitting the measurements in the form of an acoustic signal, and sensing the acoustic signal via an optical waveguide.

Abstract: A downlinking signal is transmitted downhole from the surface using drilling fluid as the communications medium. The downlinking signal includes at least a synchronization phase and a command phase. The downlinking signal is differentiated upon reception such that attributes of the synchronization phase may be used to determine corresponding attributes of the command phase. Commands may be transmitted downhole while drilling and simultaneously while using mud-pulse telemetry uplinking techniques.

Abstract: A method of generating an acoustic signal in a subterranean well can include converting optical energy to acoustic energy downhole, thereby transmitting the acoustic signal through a downhole environment. A well system can include an optical acoustic transducer disposed in the well and coupled to an optical waveguide in the well, whereby the transducer converts optical energy transmitted via the optical waveguide to acoustic energy. An optical acoustic transducer for use in a subterranean well can include various means for converting optical energy transmitted via an optical waveguide to acoustic energy in the well.

Abstract: A system and method for downhole data communication using an infrasound wave generator and receivers. The infrasound waves have a low frequency and a wavelength that is much larger than the transverse dimensions of the well. When the infrasound waves are directed down the well, the well will act as a wave guide for low frequency excitations. The receivers are operatively connected to inflow valves and other downhole equipment, and receive the infrasound waves. If the waves are of a predetermined frequency, the receivers command the valves to open or close, or otherwise control downhole equipment. The infrasound waves can also be used to probe well geometry and to identify fluid properties within the well.

Abstract: A method of synchronization between downhole components includes: generating a dual tone synchronization signal by a signal generator in a first downhole component disposed in a borehole in an earth formation, the dual tone signal including a first constituent periodic signal having a first frequency f1 and a second constituent periodic signal having a second frequency f2 that is different from the first frequency; transmitting the synchronization signal to a second downhole component disposed in the borehole; receiving the synchronization signal by a signal processor in the second downhole component, calculating a phase difference between the first constituent signal and the second constituent signal, and calculating a transmission delay based on the phase difference; and synchronizing operation of the first and second downhole components based on the delay.

Abstract: Acoustic isolators are disclosed herein. An example apparatus includes a transmitter to transmit an acoustic signal. The example apparatus also includes an acoustic isolator substantially surrounding a receiver, and the receiver is to receive the acoustic signal via an opening in the acoustic isolator. The transmitter and the acoustic isolator are coupled to a base. The acoustic isolator includes a first layer coupled to a second layer defining a plurality of spaces. The second layer is to provide an acoustic impedance mismatch.

Abstract: A method is for determining the position of a lower portion of a drill string in a bore hole. The drill string comprises a number of drill string components, each drill string component being interconnected by means of at least one joint. Several ultrasonic sensors are arranged after each other along a drill string. The method comprises localizing the position of the chamfer of the joint relative to the ultrasonic sensors.

Abstract: An acoustic transceiver assembly including a housing, an oscillator, and at least one membrane. The housing has at least one inner wall defining a cavity. The housing also has a first end and a second end defining an axis of the acoustic transceiver assembly. The oscillator is provided in the cavity. The oscillator is provided with a transducer element, and a backing mass acoustically coupled to the transducer element. The at least one membrane extends outward from the backing mass to support at least the backing mass within the cavity. The at least one membrane is flexible in an axial direction parallel to the axis of the acoustic transceiver assembly to permit the backing mass to oscillate in the axial direction, and rigid in a transverse direction to restrict lateral movement of the backing mass relative to the housing.

Abstract: A plurality of phased array acoustic communication devices are used to communicate data along a tubulation, such as a well. The phased array acoustic communication devices employ phased arrays of acoustic transducers, such as piezoelectric transducers, to direct acoustic energy in desired directions along the tubulation. The system is controlled by a computer-based controller. Information, including data and commands, is communicated using digital signaling.

Abstract: An acoustic telemetry method for use with a subterranean well can include positioning a well tool in the well, the well tool including an acoustic transmitter and a sensor, and an acoustic receiver in the well receiving an acoustic signal transmitted by the transmitter, the acoustic signal including information representative of a measurement by the sensor. A system for use with a subterranean well can include a well tool positioned in the well, the well tool including an acoustic transmitter and a sensor, the acoustic transmitter transmits an acoustic signal including information representative of a measurement by the sensor to an acoustic receiver positioned in the well.

Abstract: A system for use with a subterranean well can include a well tool which generates an acoustic signal in response to operation of the well tool, the acoustic signal being detected by an acoustic receiver in the well. A method for verification of operation of a well tool can include operating the well tool, thereby generating an acoustic signal, and an acoustic receiver receiving the acoustic signal generated by the well tool, the acoustic signal including information indicative of the well tool operating. Another system for use with a subterranean well can include a well tool which generates an acoustic signal in response to operation of the well tool, an optical waveguide which receives the acoustic signal, and an optical interrogator connected to the optical waveguide. The optical interrogator detects the acoustic signal, which is indicative of the well tool operation.

Abstract: A method for aggregating data for a drilling operation. The method includes acquiring the data from a number of data sources associated with the drilling operation, synchronizing a timing of the data for aggregating the data to generate synchronized aggregated data, determining a drilling context based on the synchronized aggregated data, and assigning the determined drilling context to the synchronized aggregated data. The method further includes analyzing the synchronized aggregated data in the drilling context to generate an analysis and presenting the analysis to at least one user.

Abstract: An influx of gas into a borehole can be detected by deploying a string of acoustic sensors along a drill string or other conduit to monitor an acoustic characteristic, such as velocity or attenuation, of the drilling fluid present in the borehole. In response to detection of acoustic pulses propagating in the drilling fluid, the acoustic sensors generate signals that are representative of acoustic characteristics if the drilling fluid. Based on the generated signals, a data acquisition system can determine whether a change in the monitored acoustic characteristic is indicative of a gas influx.

Abstract: An apparatus for creating pressure pulses in the fluid of a bore hole is described. The preferred embodiment takes the form of a mud pulser apparatus having a signalling valve controlled by a variable pilot valve. The forces on the signalling valve are balanced and controlled by the flow of mud through the variable orifice of the pilot valve. The arrangement is such as to act like a hydraulic amplifier, and results in the signalling valve being compensated for variable flow rates. In the preferred embodiment, the pilot valve has rotary vanes that allow it to be self-cleaning.

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: A subsea electronic information system for managing data related to a characteristic of subsea equipment locatable subsea. The system includes sensors locatable subsea and in communication with and capable of measuring a characteristic of the subsea equipment. A sensor interface box (SIB) separate from the sensors and locatable subsea includes a processor and a memory device capable of receiving and storing sensor measurement data. Additionally, the SIB is in data and power communication with the sensors. The system further includes a subsea retrievable data capsule capable of recording all system data over a long period. The capsule may be recovered from subsea (independently of the other elements of the information system) for forensic analysis of the recorded data.

Abstract: A communication method includes: receiving input data at a transmitter, the transmitter including at least one convolutional encoder and at least one modulator; applying the input data to a trellis-coded modulation (TCM) scheme to encode the input data and produce one or more TCM symbols representing the encoded data; applying the one or more TCM symbols to a second modulation scheme, the second modulation scheme including a pulse modulation in combination with an additional modulation; and generating one or more modulation symbols representing the encoded data based on the second modulation scheme.

Abstract: An embodiment includes a method comprising transmitting and receiving an acoustic signal that is modulated along a jointed tubing. The acoustic signal may be transmitted in multiple passbands of the jointed tubing and may be modulated differently in different passbands. A swept frequency signal may be used to determine transmission characteristics of the jointed tubing and to select the multiple passbands. Additional embodiments are disclosed.

Abstract: A system and a method use dual telemetry for tools located in a wellbore. A first telemetry system and a second telemetry system coordinate communication with the tools. Both the first telemetry system and the second telemetry system may transmit data regarding the tools and/or drilling conditions from the tools to a surface location simultaneously. The first telemetry system or the second telemetry system may communicate with the surface location if communication using the other telemetry system is interrupted. The first telemetry system and the second telemetry system may have a master/slave relationship so that data requests from a specific telemetry system do not interfere with data requests from the other telemetry system.

Abstract: A miner communication and locating system is disclosed. Two technologies used in the system include a communicator, and a locator array that may be used with a computer. The communicator portion allows trapped miners to continually signal without physical effort that they have survived a cave-in or explosion in a direct, mechanical, and reliable manner. The locator array receives the communicator signal for use to accurately identify where the survivors are underground, and facilitate their rescue; a computer can be used to calculate the position of the communicator from information provided by a plurality of locators: global positioning system receivers may be used with the locator array.

Abstract: A method, apparatus and system for estimating a parameter of interest downhole is disclosed. An acoustic source signal is generated at a drill bit downhole. The generated acoustic source signal is received at a source sensor at the drill bit. A character of the generated acoustic source signal is determined from the received signal at the source sensor. The characterized source signal is used to estimate the downhole parameter of interest.

Abstract: A method for synchronizing an actuation of a seismic source with at least one of an acquisition and storage of an acoustic wave by a seismic tool having steps of determining at least one of a drilling pause and a seismic measurement, transmitting a trigger signal to a tool controller, actuating the seismic source; receiving the trigger signal and recording seismic waves in a data storage medium.

Abstract: An apparatus and method for estimating a parameter of interest of an earth formation involving alignment information between receivers and their corresponding oriented transmitters. The method may include generating signals indicative responses to energy transmitted into an earth formation; estimating differences in alignment between transmitters and receivers; using the estimated differences in alignment to compensate for misalignment; and estimating a parameter of interest using the misalignment compensated signals. The apparatus may include a bottom hole assembly with one or more oriented transmitters, one or more oriented receivers, one or more alignment sensors, and at least one processor configured to compensate for misalignment using information about difference in alignment between the at least one oriented transmitter and at least one oriented receiver.

Abstract: A downhole tool includes a tool body, stator, and rotor. The tool body is aligned along a tool centerline and includes an aperture therethrough operable to pass a fluid to an exterior of the body. The stator is fixed relative to the tool body and includes a fluid flow restriction operable to pass at least a portion of the fluid from an interior of the stator to the exterior of the body at an adjustable flow rate. The rotor is disposed within the tool body and rotatable relative to the stator and includes an exhaust port selectively aligned with at least one aperture through the tool body by rotation of the rotor relative to the stator. The exhaust port is operable to pass at least a portion of the fluid from an interior of the rotor to the exterior of the body when aligned with the aperture.

Abstract: A downhole communication system and method is presented for communicating between a downhole location within a wellbore and a surface location. The system preferably comprises a first and second telemetry module, a downhole tool, and an interface electrically connecting the downhole tool to the first and second telemetry modules. The first telemetry module is connected to a string and positioned downhole within the wellbore, and configured to receive communication signals via acoustic propagation or low frequency electromagnetic transmission. The second telemetry module is connected to the string and positioned downhole within the wellbore, and configured to receive communication signals via fluid pressure pulse commands. The downhole tool is operatively connected to the string. And the interface is adapted to selectively relay digital communication signals between the downhole tool and at least one of the first and second telemetry modules.

Abstract: An acoustic telemetry isolation system and method for use with tubular assemblies such as drillpipe and production tubing includes an acoustic wave transmitter and an acoustic isolator. A “down” wave propagated toward the isolator is reflected back substantially in phase with an “up” wave propagated from the acoustic wave source away from the isolator. Furthermore, the acoustic isolator is similarly effective in reflecting “up” propagating waves originating from below the isolator, hence further protecting the acoustic wave source from possible deleterious interference. The construction of the isolator utilizes a specified combination of waves traveling in parallel in materials whose properties aid the beneficial combination of reflected and transmitted waves. The design of the isolator is to generally provide a bandstop filter function, thereby aiding the frequency isolation of an acoustic transmitter over a passband that may be constrained by the geometry of drill pipe or components of production tubing.

Abstract: A system and method of closed loop control whereby groupings of surface sonic transmitters disposed along the planned path of a well send sonic wave energy to a downhole sonic receiver (or alternatively a downhole sonic transmitter signalling to grouping of surface sonic receivers) in a manner that facilitates the downhole positioning of the well. Subsequent offset well positioning, relative to the first well, may be achieved in a similar manner.

Abstract: A system for directing the drilling of a well at a drill-site includes an instructing unit, an instructed unit, and a central unit. The instructed unit receives drilling instruction from an instructing driller, sends drilling instructions to the central unit, and presents to the instructing driller drilling instructions and instruction confirmations received from the central unit. The instructed unit receives instruction confirmations from an instructed driller, sends instruction confirmations to the central unit, and presents to the instructed driller drilling instructions received from the central unit. The central unit stores and forwards drilling instructions and instruction confirmations to the instructing unit and instructed unit, and generates and stores slide sheet information from the drilling instructions.

Abstract: Disclosed is a method for transmitting data from a tool disposed in a borehole penetrating the earth to a receiver. The method includes disposing the tool in a borehole and receiving a series of measurements using a processor disposed at the tool. A telemetry system transmits a latest received measurement that meets acceptance criteria to the receiver after completion of transmission of a previously transmitted measurement.

Abstract: A downhole tool system includes a first downhole tool and a second downhole tool. The first downhole tool includes a first controller operable to receive an actuation signal including a tone. The first controller actuates the first downhole tool if the tone is a first specified frequency and changes the first downhole tool to communicate the actuation signal to the second downhole tool if first downhole tool is not actuated in response to the actuation signal. A second downhole tool includes a second controller operable to receive the actuation signal. The second controller actuates the second downhole tool if the tone is a second specified frequency. The second frequency is different from the first frequency.

Abstract: The present disclosure is direct to method of performing measurements while drilling in an earth formation. The method may include estimating a location of a seismic reflector using signals from one or more of seismic sensors located at a plurality of locations in a borehole and the drilling depth of the one or more seismic sensors in a borehole. The signals may include information about times when the seismic sensors detect a direct wave and a reflected wave. The method may include storing the information in a memory using a processor.

Abstract: A technique for communicating data within a wellbore is provided. In one embodiment, a method includes receiving digital data and encoding the digital data into symbols each representative of one or more data bits of the digital data. In this embodiment, the method also includes modulating the phase of an acoustic wave within the wellbore to represent the plurality of symbols, wherein modulating the phase of an acoustic wave includes changing the phase of the acoustic wave such that the acoustic wave includes smooth phase transitions between successive phases representative of the plurality of symbols. Various additional methods, systems, and devices are also provided.

Abstract: A system for communicating with downhole tools and devices is disclosed. The system includes multiple communication devices which, in combination, permit operators at the surface to operate downhole tools and to receive feedback regarding the state of the tools.

Abstract: Apparatus for acoustic measurement in a downhole environment to enable high quality measurements to be obtained in difficult logging conditions are disclosed. An example apparatus includes a downhole tool having a body with a plurality of transmitters located on the body. A receiver is located on the body a distance from the transmitters and an attenuator section is integrally formed on the body between at least one transmitter and the receiver.

Abstract: A method and apparatus for estimating a pressure transition zone in a borehole is disclosed. A parameter indicative of formation fluid pressure at a plurality of borehole depths is measured. A global trend of the parameter is determined over a first depth interval and a local trend of the parameter is determined over a second depth interval. A relation is determined between the global trend and the local trend, and the pressure transition zone is determined from the determined relation between the determined global trend and the determined local trend.

Abstract: Methods and apparatus to process time series data for propagating signals in a subterranean formation are disclosed. An example method described herein for processing measured data comprises receiving a time series of measured data obtained by sensing a propagating signal, the propagating signal having passed through a subterranean formation, transforming the time series of measured data to generate a time-frequency representation of the time series, and processing the time-frequency representation to at least one of reduce noise in the time frequency representation, or enhance a component of the propagating signal present in the time-frequency representation.

Abstract: The invention provides a system and method for facilitating oilfield operations utilizing auditory data. In one embodiment, the present invention generates one or more auditory mapping structures whereby oilfield data may be mapped to sounds. The present invention provides at least one computer generated selection tool through which the user may select one or more portions of displayed oilfield data for auditory enhancement. Once the user has indicated an area of interest using the selection tool, the present invention may identify the oilfield data displayed within the outlined area of interest, identify auditory data associated with the displayed oilfield data utilizing one or more auditory mapping structures, and emit at least a portion of the identified auditory data to enhance the user's understanding of the displayed oilfield data.

Abstract: A method and apparatus for packaging a surface acoustic wave transponder for use in down-hole tool oil & gas environments is provided. An exemplary transponder comprises a surface acoustic wave piezoelectric device, wire bonds, an antenna element, an antenna substrate, a header, and protective coating. The exemplary surface acoustic wave piezoelectric device is attached into a header and wire bonded to the connection leads, which are connected to an antenna element, and then sealed by a protective coating. The header is hermetically sealed and withstands high pressure high temperature environment found in oil & gas down-hole environment.

Abstract: A sensing and data recording downhole system and method for monitoring of firing of a perforating gun system in a well, including a perforating gun system having charges or bullets for performing well perforation; and one or more downhole recorders and/or one or more fluid detection sensors located above, along, below or in array on the perforating gun system or inside the perforating gun system on a conveyance and configured to at least one of record sound waves generated by explosions of the charges or bullets during the firing of the perforating gun system and detect a presence of fluid within a body of the perforating gun system before and after guns of the perforating gun system are fired.

Abstract: Devices capable of being disposed in a wellbore for outputting acoustical signals for monitoring downhole parameters are described. Receiving devices positioned remote from the devices and can receive the acoustical signals and determine the downhole parameters. The devices can output acoustical signals in response to fluid flow or otherwise.

Abstract: An acoustic transmitter includes: an acoustic diaphragm configured to transmit acoustic waves into a medium; a piezoelectric actuator assembly configured to deform in an axial direction in response to an applied electrical signal; and a highly incompressible elastic material disposed between the piezoelectric actuator and the acoustic diaphragm and configured to transmit pressure waves to the acoustic diaphragm in response to motion of the piezoelectric actuator.

Abstract: This application describes methods and apparatus for downhole monitoring in real-time. The method involves interrogating an unmodified optic fibre (102) arranged along the path of a well bore (106) to provide a distributed acoustic sensor and sampling data gathered from a plurality of sensing portions of the fibre. The sampled data is then processed to provide a real-time indication of the acoustic signals detected by the sensing portions of the fibre. The real-time indication provides information to an operator or controller of the downwell process with real-time feedback data regarding what is happening during the down-well process which allows the identification of any problems and adjustment of the process parameters.

Abstract: A drilling tool having memory to store measured data, a transceiver and an embedded antenna, where a transceiver is lowered into the bore of the drilling tool to receive a radio signal from the drilling tool transceiver to receive the stored measured data. Data may also be transmitted from the lowered transceiver to the drilling tool transceiver. Various methods may be employed to cause the transmitter to transmit the stored measured data while the drilling tool is still in the borehole. Other embodiments are described and claimed.

Abstract: An MWD data transmission system and method for determining and transmitting the environmental properties of the downhole borehole assembly (BHA) to surface data receivers via mud pulse telemetry, EM telemetry, or both mud pulse telemetry and EM telemetry based on one or more determined properties of the downhole environment.

Abstract: A method of signal processing includes providing at least a first pressure sensor and a second pressure sensor spaced in a drilling system and using an algorithm to separate the downwardly propagating waves from the upwardly propagating waves. In one or more examples, an algorithm may include determining a velocity of pressure signals in a wellbore, time-shifting and stacking pressure signals from at least the first pressure sensor and the second pressure sensor to determine a downwardly propagating noise signal, and subtracting the downwardly propagating noise signal from at least the signal from the first pressure sensor.

Abstract: Purging of fiber optic conduits in subterranean wells. A downhole optical sensing system includes an optical line, at least two tubular conduits, one conduit being positioned within the other conduit, and the optical line being positioned within at least one of the conduits, and a purging medium flowed in one direction through one conduit, and flowed in an opposite direction between the conduits. A method of purging a downhole optical sensing system includes the steps of: installing at least two conduits and an optical line in a well as part of the sensing system, one conduit being positioned within the other conduit, and the optical line being positioned within at least one of the conduits; and flowing a purging medium through the conduits in the well, so that the purging medium flows in one direction through one conduit and in an opposite direction between the conduits.