Abstract: The present invention is a method and apparatus used to transmit information to the surface from a subsurface location during the process of drilling a bore hole comprising a pressure pulse generator or “pulser” coupled to a sensor package, a controller, an active electromagnetic system for subsurface collision avoidance, and a battery power source all of which reside inside a short section of drill pipe close to the bit at the bottom of the bore hole being drilled wherein the apparatus or “MWD Tool” can be commanded from the surface to make a measurement of desired parameters and transmit this information to the surface by encoding data in pressure pulses generated by a pulser valve that includes a stator and a rotor which may be open and closed to create pressure pulses.

Abstract: The present invention is a method and apparatus used to transmit information to the surface from a subsurface location during the process of drilling a bore hole comprising a pressure pulse generator or “pulser” coupled to a sensor package, a controller, an active electromagnetic system for subsurface collision avoidance, and a battery power source all of which reside inside a short section of drill pipe close to the bit at the bottom of the bore hole being drilled wherein the apparatus or “MWD Tool” can be commanded from the surface to make a measurement of desired parameters and transmit this information to the surface by encoding data in pressure pulses generated by a pulser valve that includes a stator and a rotor which may be open and closed to create pressure pulses.

Abstract: Methods and apparatus for communicating between surface equipment and downhole equipment. One embodiment of the invention provides a wellhead assembly that allows electrical power and signals to pass into and out of the well during drilling operations, without removing the valve structure above the wellhead. Another embodiment of the invention provides an electromagnetic casing antenna system for two-way communication with downhole tools. Another embodiment of the invention provides an antenna module for a resistivity sub that effectively controls and seals the primary/secondary interface gap.

Abstract: Methods and apparatus for communicating between surface equipment and downhole equipment. One embodiment of the invention provides a wellhead assembly that allows electrical power and signals to pass into and out of the well during drilling operations, without removing the valve structure above the wellhead. Another embodiment of the invention provides an electromagnetic casing antenna system for two-way communication with downhole tools. Another embodiment of the invention provides an antenna module for a resistivity sub that effectively controls and seals the primary/secondary interface gap.

Abstract: Methods and apparatus for communicating between surface equipment and downhole equipment. One embodiment of the invention provides a wellhead assembly that allows electrical power and signals to pass into and out of the well during drilling operations, without removing the valve structure above the wellhead. Another embodiment of the invention provides an electromagnetic casing antenna system for two-way communication with downhole tools. Another embodiment of the invention provides an antenna module for a resistivity sub that effectively controls and seals the primary/secondary interface gap.

Abstract: A method of determining a holdup value for a multiphase fluid. A first holdup component is calculated using a first detection technique which is insensitive to small inclusions of a first fluid constituent (hydrocarbons) dispersed in a second fluid constituent (water). A second holdup component is also calculated using a second detection technique which determines a percentage of the small inclusions of the first fluid constituent that are dispersed in the second fluid constituent. The first and second holdup components are then combined to yield a total holdup value. The method can further compensate for displacement of the second fluid constituent by the small inclusions of the first fluid constituent. The second holdup component is preferably calculated by inferring a maximum heavy phase density (MHPD) of the multiphase fluid.

Abstract: A production logging tool is provided for use within a well to directly measure a velocity profile of a multiphase fluid flow within a cross-section of a well. The production logging tool includes a tool housing from which a plurality of arms are radially extensible. The plurality of arms are rotatably mounted to the tool housing for rotating around a tool axis extending longitudinally through the tool housing. At least one Doppler flow sensor is fixedly mounted to one of the plurality of arms for moving with the arm to dispose the Doppler flow sensor within different localized regions within a cross-section of the well. The localized regions of the cross-section are located at different radial distances from and at different angular displacements around the tool axis of the tool housing, at points distal from the tool axis.

Abstract: A production logging tool is provided for use within a well to determine fluid holdup of a multiphase fluid flow within the well. The production logging tool includes a plurality of sensors secured within a plurality of arms which radially extend from a tool housing to points distal from the tool housing. A plurality of sensors are included within the plurality of arms for detecting variations in fluid properties attributable to different flow constituents of the multiphase fluid flow along a path which circumscribes an exterior of the tool housing. The plurality of arms are rotated about the tool housing for moving these sensors through the path in order to ensure that the volumetric proportions of the different flow constituents of the multiphase fluid flow are accurately detected in highly deviated and in horizontal wells.

Abstract: A downhole electrical power supply apparatus has a high fluid pressure source zone and a low fluid pressure discharge zone each defined at least partially within the apparatus. A fluid powered engine provides rotational mechanical output and is powered by fluid flowing from the source zone through the engine to the discharge zone. An electrical powered generator converts the rotational mechanical output of the engine into electrical output.

Abstract: For use with a sonde adapted to be lowered into a well borehole, the sonde supports a thermal conductivity probe response to well fluid thermal conductivity. In the preferred and illustrated embodiment, a four leg resistor bridge circuit has two temperature-sensitive legs exposed to well fluid. In addition, one such bridge leg is positioned adjacent to a heater dissipating constant heat power. The remaining leg is exposed to ambient well fluid. The bridge incremental voltage varies with the ambient temperature of the well fluid, but such ambient variations are compensated for by the remaining temperature-sensitive leg which causes nulling of ambient temperature changes. The heat transferred to the heated bridge leg determines the incremental voltage and, hence, the conductivity of fluid in the well bore can be measured.