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: The invention relates to a data transmission or telemetry system and a method for communicating information axially along a drill string. The method includes the step of conducting an axial electrical signal embodying the information between a first axial position in the drill string and a second axial position in the drill string through an axial conducting loop formed by the drill string, which axial conducting loop extends between the first and second axial positions. The system includes the axial conducting loop for conducting the axial electrical signal embodying the information between the first and second axial positions and a transmitter for transmitting the information to the axial conducting loop. The system further preferably includes a receiver for receiving the information from the axial conducting loop. Finally, the portion of the drill string forming the axial conducting loop is preferably comprised of a downhole motor drilling assembly.

Abstract: An annular wire harness for use in drill pipe comprising two rings interconnected by one or more insulated conductors. The rings are positioned within annular grooves located within the tool joints and the conductors are fixed within grooves along the bore wall of the pipe. The rings may be recessed within annular grooves in order to permit refacing of the tool joint. The rings are provided with means for coupling a power and data signal from an adjacent pipe to the conductors in such a fashion that the signal may be transmitted along the drill pipe and along an entire drill string.

Abstract: Method and system for subsurface logging utilizing a modified metallic tubular having an elongated body with tubular walls and a central bore adapted to receive a support member. The tubular including slotted stations to provide through-tubular signal transmission and/or reception. Pressure barrier means provide hydraulic isolation at the slotted stations. The support member is equipped with various sources and sensors, including an antenna adapted to generate a magnetic dipole moment with a transverse or controllable orientation, and adapted for engagement within the tubular. The apparatus is suitable for LWT, LWD, and TLC logging operations.

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 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: 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 pressure pulse generator for use in transmitting pressure signals to surface in a fluid-based drilling system. The generator is arranged in use in the path of a pressurized fluid to operate a drilling assembly and is capable of being actuated to generate pressure signals in such fluid for transmission to surface pressure monitoring equipment. The pulse generator includes pulse height compensation to keep the pulse height within acceptable limits over a wide flow range.

Abstract: A system of downhole communication and control is provided in methods and associated apparatus for data retrieval, monitoring and tool actuation. In a described embodiment, an item of equipment installed in a tubular string has a first communication device associated therewith. A tool conveyed into the tubular string has a second communication device therein. Communication is established between the first and second devices. Such communication may be utilized to control operation of the tool, retrieve status information regarding the item of equipment, supply power to the first device and/or identify the item of equipment to the tool.

Abstract: A method and apparatus for acoustically actuating wellbore tools using two-way acoustic communication is disclosed.

Abstract: A system is disclosed for generating and transmitting data signals to the surface of the earth while drilling a borehole, the system operating by generating pressure pulses in the drilling fluid filling the drill string. The system is designed to maximize signal strength while minimizing the probability of jamming by drilling fluid particulates. The system uses a rotary valve modulator consisting of a stator with flow orifices through which drilling fluid flows, and a rotor which rotates with respect to the stator thereby opening and restricting flow through the orifices and thereby generating pressure pulses. The flow orifices with the stator in a “closed” position are configured to reduce jamming, and to simultaneously minimize flow area in order to maximize signal strength. This is accomplished by imparting a shear to the fluid flow through the modulator, and minimizing the aspect ratio and maximizing the minimum principal dimension of the closed flow area.

Abstract: An electromagnetic pickup apparatus (46) and method for use of the same is disclosed. The apparatus (46) comprises a probe (60) that is insertable into a bore hole (64) or a trench (70) and a conductive backfill composition (62) that substantially surrounds the probe (60) having intimate contact with the probe (60) and the earth, thereby establishing a highly electrically conductive region (66) between the probe (60) and the earth.

Abstract: The method of remotely actuating a downhole device provides the initiation of an acoustic signal. The acoustic signal is amplified within a resonance chamber and is transmitted down a fluid column in the tubing string or in the annulus around the tubing string. The signal can be coded to allow activation of multiple downhole devices. The use of a resonance chamber allows for the amplification of the actuation signal to ensure that a downhole receiver can detect it. The receiver can be either a transducer or a hydrophone. The apparatus and method allow for remote actuation without the need for intervention into the well.