Abstract: A method and system for conducting a seismic survey by lowering a string of intelligent clampable sensor pods with 3-C sensors into a borehole. The string of pods is serially interconnected by a cable having a conductor pair which provides both power and data connectivity. The uppermost sensor pod is connected to a downhole telemetry and control module. The cables and pods use connectors to allow assembly, customization, repair, and disassembly on site. Each pod has an upper and a lower connector, a processor, and memory which is coupled to both the upper and the lower connectors. Each pod is capable of simultaneous and independent serial communications at each connector with the memory. The telemetry and control module is designed to query the pods to determine the system configuration. The telemetry and control module then simultaneously triggers all pods to acquire data, the pods storing the collected data locally in the memory.

Abstract: An attenuation apparatus, system, and method are disclosed. The attenuator is attached to a pipe and includes a housing that includes an inner sleeve and an outer sleeve. The attenuator includes one or more masses, to resonate when exposed to waves including acoustic frequency components.

Abstract: An acoustic logging tool including an elongated body, one or more acoustic transmitters, one or more acoustic receivers, and a broadband acoustic absorption region. A substantial portion of the broadband acoustic absorption region is between the transmitter and the receiver. The acoustic energy absorber includes a first absorber for absorbing a first mode of acoustic energy and a second absorber for absorbing a second mode of acoustic energy. The acoustic absorption material used to make the acoustic absorbers has an acoustic impedance between 20% and 120% of the material used to construct the acoustic logging tool. The acoustic logging tool includes an elongated hollow tool body, an insert configured to be inserted into the tool body, and a ring configured to be inserted onto the insert. A first element is supported by the ring and exposed to a pressure field, and a second element is supported by the ring and exposed to a pressure field.

Abstract: The acoustic isolator assembly of the present invention comprises a elongated cylindrical body suited for connection to an acoustic array and subsequent disposition within a wellbore. According to one embodiment of the present invention, the acoustic isolator comprises a plurality of cylindrical isolator modules that are coaxially arranged to form the body of the tool. Each isolator module comprises a spring disposed within an outer housing. The separate isolator modules are attached to one another by connecting rods around which are disposed a plurality of metal spacers. The isolator module further comprises mechanical stops that limit the deflection of the spring during high axial loading. These features enable the acoustic isolator assembly to withstand the high loading that may be applied during logging operations. Therefore, the isolator modules are capable of supporting high compressive and tensile loads without suffering permanent deformation of the springs.

Abstract: A downhole crystal-based clock that is substantially insensitive to the factors that cause frequency deviation. The clock may be maintained at a predetermined temperature using a temperature sensing device and a heating device, where the predetermined temperature corresponds to the temperature at which the crystal experiences only slight frequency deviation as a function of temperature. A microprocessor may monitor the clock and compensate for long-term aging effects of the crystal according to a predetermined algorithm. The predetermined algorithm may represent long-term aging effects of the crystal which were derived by comparing the crystal clock to a more accurate clock (e.g., an atomic clock) prior to placing the clock downhole. In this manner, the crystal-based clock may be substantially free from the factors that cause frequency, and therefore time variations.

Abstract: Methods and apparatus for isolator pad assemblies used in formation testing equipment. The pad comprises a primarily metallic pad member and a retractable resilient sealing member. The resilient sealing member is maintained in a retracted, protected position until extended to seal against the wellbore. When extended the metallic pad pushes into the mudcake until a raised ring of material on the surface of the pad contacts the formation. Once the pad is in place, the resilient sealing member, which is molded to an extending metal sleeve, is extended and contacts the mudcake to form a primary seal. With the primary and secondary seals energized, a fluid sample can be collected from the formation without contamination from wellbore fluids.

Abstract: The acoustic isolator assembly of the present invention comprises a elongated cylindrical body suited for connection to an acoustic array and subsequent disposition within a wellbore. According to one embodiment of the present invention, the acoustic isolator comprises a plurality of cylindrical isolator modules that are coaxially arranged to form the body of the tool. Each isolator module comprises a spring disposed within an outer housing. The separate isolator modules are attached to one another by connecting rods around which are disposed a plurality of metal spacers. The isolator module further comprises mechanical stops that limit the deflection of the spring during high axial loading. These features enable the acoustic isolator assembly to withstand the high loading that may be applied during logging operations. Therefore, the isolator modules are capable of supporting high compressive and tensile loads without suffering permanent deformation of the springs.

Abstract: An acoustic logging tool including an elongated body, one or more acoustic transmitters, one or more acoustic receivers, and a broadband acoustic absorption region. A substantial portion of the broadband acoustic absorption region is between the transmitter and the receiver. The acoustic energy absorber includes a first absorber for absorbing a first mode of acoustic energy and a second absorber for absorbing a second mode of acoustic energy. The acoustic absorption material used to make the acoustic absorbers has an acoustic impedance between 20% and 120% of the material used to construct the acoustic logging tool. The acoustic logging tool includes an elongated hollow tool body, an insert configured to be inserted into the tool body, and a ring configured to be inserted onto the insert. A first element is supported by the ring and exposed to a pressure field, and a second element is supported by the ring and exposed to a pressure field.

Abstract: The invention is a method and apparatus for acoustic logging including one or more acoustic transmitters and one or more acoustic receivers. One or more of the elements of a set made up of the acoustic receivers and acoustic transmitters are spaced radially apart from one or more of the remaining elements of the set. The acoustic receivers and acoustic transmitters are configured along with electronics and software incorporated in the tool to allow the acoustic receivers and acoustic transmitters to act as multi-pole receivers and multi-pole transmitters, respectively. The tool is configured to compute one or more acoustic velocities and to provide storage for unprocessed and processed, compressed and error correction coded data. The tool is configured to provide the data for transmission to the surface.

Abstract: An acoustic logging tool including an elongated body, one or more acoustic transmitters, one or more acoustic receivers, and a broadband acoustic absorption region. A substantial portion of the broadband acoustic absorption region is between the transmitter and the receiver. The acoustic energy absorber includes a first absorber for absorbing a first mode of acoustic energy and a second absorber for absorbing a second mode of acoustic energy. The acoustic absorption material used to make the acoustic absorbers has an acoustic impedance between 20% and 120% of the material used to construct the acoustic logging tool. The acoustic logging tool includes an elongated hollow tool body, an insert configured to be inserted into the tool body, and a ring configured to be inserted onto the insert. A first element is supported by the ring and exposed to a pressure field, and a second element is supported by the ring and exposed to a pressure field.

Abstract: The invention is a method and apparatus for acoustic logging including one or more acoustic transmitters and one or more acoustic receivers. One or more of the elements of a set made up of the acoustic receivers and acoustic transmitters are spaced radially apart from one or more of the remaining elements of the set. The acoustic receivers and acoustic transmitters are configured along with electronics and software incorporated in the tool to allow the acoustic receivers and acoustic transmitters to act as multi-pole receivers and multi-pole transmitters, respectively. The tool is configured to compute one or more acoustic velocities and to provide storage for unprocessed and processed, compressed and error correction coded data. The tool is configured to provide the data for transmission to the surface.

Abstract: An acoustic logging apparatus includes a tool body and a housing. A transducer operating in the bending mode is mounted in the housing. The transducer operates such that it is excited by or emits acoustic energy in only one of the two directions substantially perpendicular to the face of the transducer. The housing is mounted substantially removed from the axis of the body. An acoustic receiver includes an outer sleeve having a flange and a hat slidably mounted within the outer sleeve. The sliding of the hat compensates for variations in pressure and temperature. An acoustic transmitter includes a main housing and a hat slidably supported within the main housing. The sliding of the hat compensates for variations in pressure and temperature. Combinations of air gaps and o-rings in the transducer acoustically isolate a piezoelectric crystal from its housing and the housing from its enclosure. The acoustic receiver and acoustic transmitter are configured to be replaced in the field.

Abstract: An acoustic logging tool, useful for creating a circumferential image of an earth borehole or well casing, which includes one or many acoustic transceivers mounted in substantially the same plane, in a drill string sub. The mounting receptacles are located in blocks, flexibly mounted in fixed inserts within the interior of the drill string sub. Each of the transceivers is structured to provide temperature and pressure compensation. The echo signals received by the transceivers are digitized and processed to eliminate extraneous noise created by the ringing of the transducers, by the signals reflected from the material backing the transducer ultrasonic element, and by any other sources inherent to the drilling environment. Digitization and further processing also allows for signal enhancement, thus allowing detection of signals in the presence of substantial noise.

Abstract: An adjustable valve for controlling fluid flow between an inlet and an outlet in a valve. A compressed spring biases a valve member against the valve inlet to prevent fluid flow until the fluid pressure reaches a certain level. One end of the spring contacts a hydraulic plunger which is moved with a hydraulic fluid. The hydraulic fluid pressure can be raised to increase the spring force acting against the valve element, and the hydraulic fluid pressure can be reduced to decrease the spring force acting against the valve element. The flow rate at the valve outlet can be monitored, and flow rate signals can be transmitted to a controller for adjusting the hydraulic fluid pressure in response to the flow rate detected.

Abstract: An assembly for dispensing a core separator ring on the top of a previously-cut core that is ejected from a core-cutting bit in a storage bin. The core separator assembly is integral with the forward end of the core ejector system.