Abstract: A robust transmission element for transmitting information between downhole tools, such as sections of drill pipe, in the presence of hostile environmental conditions, such as heat, dirt, rocks, mud, fluids, lubricants, and the like. The transmission element maintains reliable connectivity between transmission elements, thereby providing an uninterrupted flow of information between drill string components. A transmission element is mounted within a recess proximate a mating surface of a downhole drilling component, such as a section of drill pipe. The transmission element may include an annular housing forming a trough, an electrical conductor disposed within the trough, and an MCEI material disposed between the annular housing and the electrical conductor.

Abstract: An improved data telemetry system for multi-conductor wirelines to achieve satisfactory transmission of analog and digital signals with frequency content up to 100 kHz by assigning at least two conductors to a first terminal of a data transmittal means and to a first terminal of a data receiver means and connecting at least one additional conductor to a second terminal of a data transmittal means and to a second terminal of a data receiver means. Pairing conductors reduces attenuation and crosstalk and permits the signal to contain multiple frequency modulated carrier bands with individual channel bandwidths of up to 3 kHz or higher.

Abstract: A robust transmission element for transmitting information between downhole tools, such as sections of drill pipe, in the presence of hostile environmental conditions, such as heat, dirt, rocks, mud, fluids, lubricants, and the like. The transmission element maintains reliable connectivity between transmission elements, thereby providing an uninterrupted flow of information between drill string components. A transmission element is mounted within a recess proximate a mating surface of a downhole drilling component, such as a section of drill pipe. To close gaps present between transmission elements, transmission elements may be biased with a “spring force,” urging them closer together.

Abstract: An electromechanical transducer formed by an electrical and mechanical combination of a piezoelectric device and a magnetostrictive device. The two devices are electrically coupled so that their capacitive and inductive reactances approach a balance to provide an essentially resistive combined input at a selected frequency. Efficiency of circuits driving the transducer is improved. The devices are mechanically coupled so that the mechanical outputs add or reinforce each other. Two transducer pairs may be used in a two frequency telemetry system with each pair tuned to one of the frequencies for optimal reactance balancing and transduction efficiency.

Abstract: The specification discloses algorithms for error recovery in pulse position modulation-based mud pulse telemetry. More particularly, the specification discloses detection and attempted correction of at least five possible error mechanisms: the missed detection of a pulse that creates an interval greater than maximum; the missed detection of a pulse that results in an interval still within acceptable boundaries; detection of an extra pulse; a pulse shift that results in data in contiguous intervals being affected; and a pulse shift resulting in a single interval data corruption.

Abstract: The present invention relates to a drill string fitted with information transmission means. The hollow rods of conductive material have their inside faces covered in an insulating material. The transmission means comprise a first electrical unit having at least a first annular electrode secured to the insulating inside face of the drill string, said electrode being in electrical contact with the mud contained inside the drill string so as to establish a flow of current in the conductive mud; and a second electrical unit disposed in said borehole, close to the top end of the drill string in order at least to receive the information contained in said electrical current.

Abstract: A system and method of communicating among devices via a piping structure using at least one induction choke about the piping structure to route a time-varying current carrying communication signals between the devices. A communications system comprises a piping structure, a first communication device, a second communication device, and an induction choke. The piping structure comprises a first location, a second location, and an electrically conductive portion extending between the first and second locations. The first and second locations are distally spaced along the piping structure. The first and second communication devices are each electrically connected to the electrically conductive portion of the piping structure along the first location and second location, respectively, and each is adapted to send and receive communication signals via time-varying current.

Abstract: The invention relates to a hollow drilling rod for transmitting information, said rod being for placing in a borehole filled with drilling mud. The rod comprises an electrically conductive cylindrical wall (521, 522) having an inside face, an outside face, a first end provided with a male coupling sleeve (62), and a second end provided with a female coupling sleeve (60), and being characterized in that it further comprises: a layer of electrically insulating material (70) covering the inside face over its entire length; and a conductive layer (80) covering said insulating layer and electrically connected at its ends to two electrically conductive rings, said conductive layer itself being covered by a second insulating layer (86) leaving said conductive rings in contact with the drilling mud.

Abstract: The invention describes a method and apparatus for effectively communicating data along the acoustic channel of a subterranean well. The method comprises optimally driving an acoustic transmitter with an adaptive transmitter controller. A data signal is transmitted along the acoustic channel and detected as a distorted signal along the acoustic channel. The distorted signal is input to the adaptive transmitter controller which, based on the detected signal, modifies later transmissions to counteract the distorting effects of the transmitter and acoustic channel. The adaptive transmitter controller preferably comprises a neural network. Another receiver may be employed, at a point further from the transmitter, to receive the optimized signals.

Abstract: A downlink telemetry system providing improved apparatus and methods for communicating instructions via pressure pulses from surface equipment to a downhole assembly. The apparatus comprises a surface transmitter for generating pressure pulses, a control system, and a downhole receiver for receiving and decoding pulses. In operation, a bypass valve is opened and closed to create a series of pressure pulses received and decoded by a downhole receiver. The method significantly reduces the time required for downlink communication without interrupting drilling and without interrupting uplink communications such that simultaneous, bi-directional communication is achievable if the uplink and downlink signals are sent at different frequencies. The telemetry scheme and algorithm provide an inventive method for filtering and decoding the downlink signals. The algorithm determines the time intervals between pulse peaks and decodes the intervals into an instruction.

Abstract: The present disclosure provides several methods for selecting and transmitting information from downhole using more than one channel of communication wherein data streams transmitted up each communications channel are each independently interpretable without reference to data provided up the other of the communications channels. Preferred embodiments incorporate the use of a combination of at least two of mud-based telemetry, tubular-based telemetry, and electromagnetic telemetry to achieve improved results and take advantage of opportunities presented by the differences between the different channels of communication.

Abstract: A petroleum well for producing petroleum products that incorporates a system adapted to controllably route communications and/or electrical power having a time-varying current through a piping structure in the well, and methods of producing petroleum products use such a well, are provided by the present invention. The system comprises a first induction choke, a second induction choke, and a controllable switch. The first induction choke is located about a portion of a first branch of the piping structure. The second induction choke is located about a portion of a second branch of the piping structure. The controllable switch having two switch terminals. A first of the switch terminals I is electrically connected to the piping structure on a junction side of the induction chokes. The first and second branches of the piping structure intersect on the junction side of the induction chokes.

Abstract: The invention is directed to a borehole logging apparatus for deep well drilling, with a signal transmitter for transmitting measured data obtained while drilling from a borehole through the drilling fluid to the earth's surface, and with an elongated housing which is adapted for insertion in the drilling fluid conduit of a drill string. Accommodated in the housing is a flow regulator with a control piston, which controls the cross-section of opening of a bypass opening in response to the pressure differential generated by a flow restrictor and in response to the force of a spring in such manner that the part of the drilling fluid current fed to the signal transmitter through the flow restrictor is maintained substantially constant, and the remaining excess drilling fluid current is routed to the drilling fluid conduit via the bypass opening.

Abstract: An apparatus for use in drilling or producing from a well bore, the apparatus comprising a downhole member such as a drilling device or a production device which is capable of being attached to a tubular such as a drill string, production string or the like, means for rotating a tubular, control means for controlling the rotation of said tubular in order to transmit information along said tubular and means for monitoring the rotation of said tubular and for decoding said information transmitted along said tubular such that a magnitude of a parameter can be determined by the drilling member from the rotation or said tubular. The invention also relates to a method for communicating with a downhole tool using the apparatus.

Abstract: A method and system for data transmission where data is encoded in a number of messenger modules that are physically transported by a natural or artificially created fluid flow or in a slurry stream from one location to one or more other locations to transmit the data. In a specific embodiment, the invention is directed to the use of such messenger modules for continuous, quasi-continuous or time-dependent data transmission between surface-based equipment and a logging tool placed in a borehole and vice versa, or between various locations in the borehole.

Abstract: A method of transmitting information between a salt-cavern and the surface of the ground, the cavern being drilled in geological formation beds and being connected to the surface via an access borehole cased at least in part by metal tubes and presenting at least one safety valve, the method consisting in suspending a string of tools from a hanger system positioned in the access borehole downstream from the safety valve and in electrical contact with the metal tubes, the string of tools including at least one measuring device connected to the hanger system via a first segment of conductor cable and an information transceiver operating by means of waves and connected to the measuring device via a second segment of conductor cable, the transceiver being positioned in such a manner as to be in contact with structural means linked to the cavern; and establishing coupling between the transceiver and the structural means, in order to enable information to be transmitted between the measuring device and the surface

Abstract: A device, system, and methods of use for wireless transmission of a detected parameter obtained from inside a wellbore is disclosed. The wireless device comprises an acoustic wireless transceiver and a selectively expandable acoustic coupler operatively in communication with the acoustic wireless transceiver, the acoustic coupler adapted to physically couple the acoustic wireless transceiver with an interior of a tubular and acoustically transmit and/or receive data. The wireless monitoring device is deployed through a tubular to a predetermined position within the tubular, a predetermined portion physically coupled to the tubular once the monitoring device reaches the predetermined position, and data transmission acoustically coupled between the monitoring device and a remote receiver through the tubular.

Abstract: This invention relates to a power line communication (PLC) system wherein the power supply line supplies power and also acts as a communications supply line. A receiver is able to detect small changes in the modulated transmitted information and thereby shut down the circuit. The invention is particularly suitable for use where the IEL is remote from the power supply such as, for example, in down hole oil production situations where very long power cables are used.

Abstract: A method and a downhole telemetry system a downhole telemetry system using discrete multitone modulation for transmitting a data stream over a plurality of transmission modes is provided. The downhole telemetry system includes a downhole transmitter, a cable, and a surface receiver. The downhole transmitter is configured to transmit the data stream over the plurality of transmission modes. The surface receiver is coupled to the downhole transmitter via the cable and is configured to combine signals from each of the plurality of transmission modes to obtain the data stream transmitted by the downhole receiver. The method includes receiving a plurality of signals over the plurality of transmission modes from a downhole package, and may further include combining the plurality of signals to form at least one data stream.

Abstract: The present invention provides a self-contained sensor module for use in a subterranean well that has a well transmitter or a well receiver-associated therewith. In one embodiment, the sensor module comprises a housing, a signal receiver, a parameter sensor, an electronic control assembly, and a parameter transmitter; the receiver, sensor, control assembly and transmitter are all contained within the housing. The housing has a size that allows the module to be positioned within a formation about the well or in an annulus between a casing positioned within the well and an outer diameter of the well. The signal receiver is configured to receive a signal from the well transmitter, while the parameter sensor is configured to sense a physical parameter of an environment surrounding the sensor module within the well. The electronic control assembly is coupled to both the signal receiver and the parameter sensor, and is configured to convert the physical parameter to a data signal.

Abstract: A method for reducing noise in borehole electromagnetic telemetry systems in which a signal receiver is positioned at a distance from a drill site borehole at which the signal receiver couples strongly to a signal from a signal transmitter disposed in the borehole and weakly to drill site noise emanating from the drill borehole, a noise receiver is positioned at a distance from the drill site borehole at which the noise receiver couples substantially only to magnetotelluric and/or drill site noise, the contributions of the magnetotelluric noise and drill site noise are determined, and subtracted from the signal received by the signal receiver, resulting in a reduced noise signal.

Abstract: A transmission line network system for transmitting and/or receiving data from a downhole tool. The invention is achieved by providing one or more transceiving elements, preferably rings, at either end of a downhole tool. A conduit containing a coaxial cable capable of communicating an electrical signal is attached to the transceiving element and extends through a central bore of the downhole tool and through the central bore of any tool intermediate the first transceiving element and a second transceiving element. Upon receiving an electrical signal from the cable, the second transceiving element may convert such signal to a magnetic field. The magnetic field may be detected by a third transceiving element in close proximity to the second transceiving element. In this manner, many different tools may be included in a downhole transmission network without requiring substantial modification, if any, of any particular tool.

Abstract: A robust data transmission element for transmitting information between downhole components, such as sections of drill pipe, in the presence of hostile environmental conditions, such as heat, dirt, rocks, mud, fluids, lubricants, and the like. The data transmission element components include a generally U-shaped annular housing, a generally U-shaped magnetically conductive, electrically insulating element such as ferrite, and an insulated conductor. Features on the magnetically conducting, electrically insulating element and the annular housing create a pocket when assembled. The data transmission element is filled with a polymer to retain the components within the annular housing by filling the pocket with the polymer. The polymer can bond with the annular housing and the insulated conductor but preferably not the magnetically conductive, electrically insulating element.

Abstract: A system and method in accordance with the invention communicator remotely with remotely controllable down hole tools in a well bore at a drilling installation. At the surface, high energy pressure impulses directed into the tubing or the annulus, or both, being at a level to propagate through an interface between very different impedances zones, such as an upper level gas zone and a lower level of mobile fluid media extending down into the desired downhole location. The pressure impulses, provided by directionally gating along the longitudinal confining path a pressure impulse initially having sharp leading and trailing edges, reach the downhole location as physical perturbations forming a discernible pattern that can be detected by one or more energy responsive transducers. With combinations of these signals, one of a number of separate control devices can be remotely actuated.

Abstract: A signal transmission connection for a tool string used in exploration and production of natural resources, namely: oil, gas, and geothermal energy resources. The connection comprises first and second annular elements deployed in cooperative association with each other. The respective elements comprise inductive transducers that are capable of two-way signal transmission between each other, with downhole components of the tool string, and with ground-level equipment. The respective inductive transducers comprise one or more conductive loops housed within ferrite troughs, or within ferrite trough segments. When energized, the conductive loops produce a magnetic field suitable for transmitting the signal. The second element may be rotational in drilling applications. The respective elements may be fitted with electronic equipment to aid and manipulate the transmission of the signal. The first element may also be in communication with the World Wide Web.

Abstract: A section of pipe for well operations has a cylindrical fiber composite pipe body and a pair of metallic end fittings. The end fittings differ from each other in that they are provided with mating key features to ensure proper angular or rotational alignment between two abutting sections of pipe. Each pipe is also provided with an optical fiber for data transmission. A fiber optic coupling is located at each end of the optical fiber for sending and receiving data transmissions via optical signals. Multiple strings of pipe are abutted end to end to complete both mechanical and data interfaces. At the junction of each pair of adjacent pipes, the end fittings axially and rotationally align. The flanges of the end fittings are fastened together with bolts such that data transmission takes place between the optical fibers.

Abstract: A pressure pulse generator to generate pressure signals in drilling fluid for transmission to surface comprising: an outer housing (100) having an inlet (9) and an outlet for supply to the drilling assembly (59); a control element (10) slidably mounted in the housing (100) for opening and closing said inlet (9), said element being operative to generate a pressure pulses when it closes; a control passage (26, 27, 28) extending through the element (10) and closable by a valve element (36) arranged to be exposed to the pressure in the passage; and an actuator assembly (13, 14, 15, 17, 19, 21, 35, 36, 37) connected to the control element (10). The control element moves upon activation (10) relative to the inlet to generate a pulse. When deactivated, it blocks the flow through the passage (26, 27, 28) so that all of the fluid bypasses via the inlet.

Abstract: A method and apparatus for transmitting information to the surface from down hole in a well in which a pulser is incorporated into the bottom hole assembly of a drill string that generates pressure pulses encoded to contain information concerning the drilling operation. The pressure pulses travel to the surface where they are decoded so as to decipher the information. The pulser includes a stator forming passages through which drilling fluid flows on its way to the drill bit. The rotor has blades that obstruct the flow of drilling fluid through the passages when the rotor is rotated into a first orientation and that relieve the obstruction when rotated into a second orientation, so that oscillation of the rotor generates the encoded pressure pulses. An electric motor, under the operation of a controller, drives a drive train that oscillates the rotor between the first and second orientations.

Abstract: An apparatus and method of communicating in a tubular system (20) through a media (65) disposed therein and actuating a controllable device (58) are disclosed. The apparatus and method utilize a transmission apparatus (16) at a transmission node that is in communication with the media (65). The transmission apparatus (16) generates pressure impulses that are propagated through the media (65). The pressure impulses may be either positive or negative pressure impulses depending upon the selected transmission apparatus. The pressure impulses are detected by a reception apparatus (77) at a reception node. The detection apparatus may detect the pressure impulses as variation in the media (65) or as variation in the tubular system (20) caused by the pressure impulses. Once the detection apparatus (77) has detected the appropriate pressure impulse or pattern of pressure impulses, a signal may be generated to actuate the controllable device (58).

Abstract: The invention is directed to a borehole logging apparatus for deep well drilling, with a signal transmitter for transmitting measured data obtained while drilling from a borehole through the drilling fluid to the earth's surface, and with an elongated housing which is adapted for insertion in the drilling fluid conduit of a drill string. Accommodated in the housing is a flow regulator with a control piston, which controls the cross-section of opening of a bypass opening in response to the pressure differential generated at an entrance opening of the housing and the force of a spring, in such manner that the part of the drilling fluid current delivered to the housing conduit, which is fed to the signal transmitter, is maintained substantially constant, and the remaining excess drilling fluid current is routed to the drilling fluid conduit via the bypass opening.

Abstract: A petroleum well (20) for producing petroleum products that incorporates a system adapted to controllably route communications and/or electrical power having a time-varying current through a piping structure (30 and/or 40) in the well (20), and methods of producing petroleum products use such a well, are provided by the present invention. The system comprises a first induction choke (70 or 100), a second induction choke (70 or 100), and a controllable switch (90). The first induction choke (70 or 100) is located about a portion of a first branch (26) of the piping structure (30 and/or 40). The second induction choke (70 or 100) is located about a portion of a second branch (29) of the piping structure (30 and/or 40). The controllable switch (90) comprises two switch terminals. A first of the switch terminals is electrically connected to the piping structure (30 and/or 40) on a junction side (81) of the induction chokes (70 or 100).

Abstract: In a borehole logging apparatus (1) for deep well drillings having a device for transmitting measured data obtained while drilling from a borehole through the drilling fluid to the earth's surface, there is arranged in the upper end of a housing (2) a signal transmitter (13) comprising a beaker-shaped rotor (24) and a stator sleeve (25) surrounding said rotor. Fluid impinges on the signal transmitter (13) through a central feed pipe (15) surrounded by an exchangeable bypass ring (14) to which the complete current of drilling fluid is routed through a filter pipe (3) and through which part of the drilling fluid current is routed back into the drill string (6). From a set of bypass rings (14) of different bypass cross sections it is possible to select one suited for the particular on-site conditions and insert it into the logging apparatus (1) in order to obtain a significant signal through the signal transmitter (13).

Abstract: A system and method of communicating among devices via a piping structure using at least one induction choke about the piping structure to route a time-varying current carrying communication signals between the devices. A communications system comprises a piping structure, a first communication device, a second communication device, and an induction choke. The piping structure comprises a first location, a second location, and an electrically conductive portion extending between the first and second locations. The first and second locations are distally spaced along the piping structure. The first and second communication devices are each electrically connected to the electrically conductive portion of the piping structure along the first location and second location, respectively, and each is adapted to send and receive communication signals via time-varying current.

Abstract: Energy dissipating loads are controlled from a location remote from the load. Load control information is transmitted between the remote location and the load by way of electrical energy transmission lines including a neutral conductor, a ground conductor and a line conductor. Load control information representative of the electrical energy applied to the load is determined and the load control information and applied to the energy transmission lines at an impressing end for transmission to a receiving end wherein the load control information is impressed between the neutral conductor and the ground conductor to provide impressed load control information. The impressed load control information is received at the receiving end by obtaining the load control information from between the neutral conductor and the ground conductor to provide received load control information. The energy of the load is controlled in accordance with the received load control information.

Abstract: A communication system is disclosed enabling communication from a surface location to a downhole location where instructions communicated are executed. The system employs accelerometers to sense vibrations traveling within the annulus fluid or the tubing string. The accelerators provide signals representative of the vibration generated at the surface of the well to a microcontroller. The microcontroller is programmed to energize a nichrome element to actuate the downhole tool in response to a user-defined vibration sequence. The vibration sequence includes a defined number of vibration cycles. Each cycle includes alternating periods of vibration and no vibrations with each period lasting for a defined length of time. The user may program the parameters of the sequence and arm the vibration receiving unit on site through a handheld terminal that interfaces with the microcontroller.

Abstract: A method and system for telemetry through a drilling fluid during drilling is disclosed. A reflector (110) is positioned downstream from the drilling mud pumps (80) and causes reflected pressure waves having the same pressure polarity as incident pressure waves traveling upwards. At least one pressure sensor (92) is positioned below the reflector (110) to sense pressure in the drilling fluid. The reflector can be a fixed orifice plate or an adjustable aperture.

Abstract: A pressure pulse sensor and associated methods provide enhanced functionality and convenience in detecting pressure pulses. In a described embodiment, a hydrophone includes a stack of disc-shaped lead titanate piezoelectric crystals enclosed within an epoxy membrane and a mounting portion which is aligned with a center of mass of the crystal stack.

Abstract: A well control system and associated method of controlling well tools provides downhole well tool control without requiring the use of electricity or complex pressure pulse decoding mechanisms. In a described embodiment, a digital hydraulic well control system includes multiple well tool assemblies, with each assembly including a well tool, an actuator and an addressable actuation control device. Multiple hydraulic lines are interconnected to each control device. The hydraulic lines transmit addresses or codes to respective selected ones of the control devices, thereby selecting corresponding respective ones of the well tools for actuation thereof. Hydraulic lines are also used to actuate the selected well tools.

Abstract: An apparatus and method is presented for establishing electrical connection to permanent downhole oilfield installations using an electrically insulated conducting casing. Current is caused to flow in the casing by a source on the surface connected to the casing. One or more permanent downhole installations are electrically connected to the casing, and the electrical connection to the casing is used to power the downhole installations. The downhole installations also inject a signal into the insulated casing that passes via the casing to a surface readout which detects and records the downhole signals.

Abstract: A sequential hydraulic well control system provides actuator selection and operation utilizing pressure applied to hydraulic lines in a sequence. In a disclosed embodiment, an actuation control device of a well control system includes multiple pistons, at least one of which is included in a latch for selectively permitting and preventing displacement of another of the pistons. When one of the pistons displaces in response to pressure applied sequentially to hydraulic inputs of the control device, an associated actuator is placed in fluid communication with the inputs.

Abstract: A reservoir production control system includes a plurality of wells for producing a reservoir linked to a central computer over a downhole communication network and a surface communication network. Both the downhole and the surface communication networks are wireless communications paths for transmitting downhole data and surface data to the central computer. Both networks include a series of interconnected tubing or pipe that allows transmission of data over electrically isolated portions of the pipe and tubing. After integrating and analyzing all relevant data and comparing the data with a reservoir model, the central computer initiates changes in a plurality of downhole control devices associated with the wells, thereby optimizing the production of the reservoir.

Abstract: A hydraulic actuator system includes a power source, a controller in communication with the power source, a piezoelectric stack comprising a plurality of piezoelectric elements disposed within a sleeve to define a chamber at one end of the sleeve, pressure accumulators in fluid communication with the chamber, a flow control valve in communication with the accumulators, and a hydraulic piston in fluid communication with the flow control valve. The communication between the power source and the controller may be electrical or photo communication, and the power source is preferably remotely located relative to the other elements of the hydraulic actuator system. The method for controlling a remotely located hydraulic actuator includes communicating a signal to the hydraulic actuator, pressurizing a hydraulic fluid in the hydraulic actuator, and directing the hydraulic fluid to a cylinder in the hydraulic actuator to bias a piston either into or away from the cylinder.

Abstract: A hybrid, hardwired (4) and wireless (8) well communication system comprises a fiber optical, electrical or other signal transmission conduit (4) extending from the wellhead into the well and one or more wireless signal transducers (7) that are located at a distance from the conduit (4) and transmit wireless signals (8) to one or more signal converters (5) which are coupled to the conduit, and which are located near branchpoints (3) of a multilateral well.

Abstract: A downlink telemetry system providing improved apparatus and methods for communicating instructions via pressure pulses from surface equipment to a downhole assembly. The apparatus comprises a surface transmitter for generating pressure pulses, a control system, and a downhole receiver for receiving and decoding pulses.

Abstract: A reprogrammable data communications system for use in a gas or oil well borehole is disclosed. The borehole includes a casing and a piping structure therein and at least one downhole equipment module located therein. The system provides for data and control signals to be coupled to the casing and piping structure by a surface modem and transmitted to the downhole equipment located in the downhole equipment modules. The downhole equipment modules include a downhole modem that is coupled to the casing and piping structure and receives the transmitted data and command signals and recovers the transmitted data and commands therefrom. A downhole processor is coupled to the downhole modem and receives the data and commands from the downhole modem and stores the data and commands in retentive memory that is coupled to the downhole processor. In this way, the downhole processor can be reprogrammed with new algorithms and communications parameters.

Abstract: A subsea communication system is used to communicate between a position that is proximal to a surface of the sea and an apparatus of the seabed. The subsea communication system includes an umbilicalless communication system.

Abstract: A telemetry system involving a shear-type mud pulser valve as the preferred embodiment is described. The control system includes a motor driver for the mud pulser which, in essence, moves one movable plate with respect to a stationary plate to create openings of various sizes. Pressure is sensed uphole of the pulser valve and is compared in real time to the desired pressure pulse amplitude. By allowing different relative rotational positions of the rotatable plate with respect to the stationary plate, different amplitudes can be achieved to further enhance the transmission of data to the surface. The control system compensates for wear in the mud pulser valve itself as well as drastic changes in mud flow and pressure. The configuration is simple and not prone to fouling from grit or other particles in the mud.

Abstract: An apparatus and method of communicating in a tubular system (20) through a media (65) disposed therein and actuating a controllable device (58)are disclosed. The apparatus and method utilize a transmission apparatus (16) at a transmission node that is in communication with the media (65). The transmission apparatus (16) generates pressure impulses that are propagated through the media (65). The pressure impulses may be either positive or negative pressure impulses depending upon the selected transmission apparatus. The pressure impulses are detected by a reception apparatus (77) at a reception node. The detection apparatus may detect the pressure impulses as variation in the media (65) or as variation in the tubular system (20) caused by the pressure impulses. Once the detection apparatus (77) has detected the appropriate pressure impulse or pattern of pressure impulses, a signal may be generated to actuate the controllable device (58).

Abstract: A system and method of communicating among devices via a piping structure using at least one induction choke about the piping structure to route a time-varying current carrying communication signals between the devices. A communications system comprises a piping structure, a first communication device, a second communication device, and an induction choke. The piping structure comprises a first location, a second location, and an electrically conductive portion extending between the first and second locations. The first and second locations are distally spaced along the piping structure. The first and second communication devices are each electrically connected to the electrically conductive portion of the piping structure along the first location and second location, respectively, and each is adapted to send and receive communication signals via time-varying current.

Abstract: An acoustic transmission system is presented, wherein acoustic communication is transmitted over an acoustic medium comprising production tubing, well casing or over continuous tubing in a well (e.g., coil tubing, chemical injection tubing or dewatering string). More specifically, the acoustic medium has an acoustic tool associated therewith, which is permanently located downhole with the sensors and electromechanical devices typically employed in a well, and an acoustic tool associated therewith uphole. The downhole sensors are connected to the downhole acoustic tool for acoustic communication. The acoustic tool includes a piezoelectric ceramic transducer (i.e., a stack of piezoelectric elements) or an accelerometer for transmitting or receiving acoustic signals transmitting through the medium.