Precision Energy Services, Inc.

Numar Corporation

Dresser Industries, Inc.

Halliburton Energy Services, Inc.

Baroid Technology, Inc.

Precision Drilling Technology Services Group, Inc.

Weatherford Canada Partnership

Dale Allen Jones

Medhat Mickael

Paul F Rodney

Manfred G Prammer

George David Goodman

Marian Morys

James H Dudley

Chen-Kang David Chen

Michael Louis Larronde

Roger P Bartel

Peter Masak

John E Smaardyk

John R Menconi

Scott E Woloson

Donald A Phelps

John E Wright

Andrew T Franzen

A monopole acoustic transmitter for logging-while-drilling comprising as a ring that comprises one or more piezoelectric arc segments. The ring is oriented in a plane whose normal is essentially coincident with the major axis of a logging tool in which it is disposed. The ring disposed within a recess on the outer surface of a short, cylindrical insert. The insert is inserted into a drill collar, rather than into the wall of the collar. The ring can comprise a continuous ring of piezoelectric material, or alternately arc segments or active ring segments of piezoelectric ceramic bonded to segments of other materials such as alumina to increase the frequency or heavy metals such as tungsten to reduce the frequency. The material and dimensions of the material used in-between the piezoelectric segments is chosen to alter the frequency of the ring.

Monopole acoustic transmitter ring comprising piezoelectric material

An acoustic transmitter with preferably a plurality of piezoelectric plates configured to optimized acoustic pressure output within a desired frequency range while meeting physical restrictions of LWD and MWD logging systems. The transmitter is disposed in a recess in the perimeter of a logging tool housing to reduce acoustic pressure waves transmitted directly along the tool housing and to optimize acoustic energy transmission into the borehole environs. In order to increase acoustic pressure output at a desired logging frequency range, the plurality of piezoelectric plates are connected electrically in parallel and fired simultaneously. The polarity of the plates and the wiring arrangement are such that each plate expands or contracts in a common direction during simultaneous firing by an applied voltage. The desired output frequency is obtained by selectively polarizing and dimensioning the plates within the plate assembly. The plate assembly is preferably disposed within an oil filled pressure housing that is pressure and temperature compensated.

Acoustic transmitter comprising a plurality of piezoelectric plates

A monopole acoustic transmitter with at least one disc assembly with a plurality of piezoelectric discs configured to optimized acoustic pressure output within a desired frequency range while meeting physical restrictions of LWD and MWD logging systems. The transmitter is disposed in a recess or 'slot' in the perimeter of a logging tool housing to reduce acoustic pressure waves transmitted directly along the tool housing and to optimize acoustic energy transmission into the borehole environs. In order to increase acoustic pressure output at a desired logging frequency range, the plurality of piezoelectric discs in each of at least one disc assembly are connected electrically in parallel and fired simultaneously. The polarity of the discs and the wiring arrangement are such that each disc expands or contracts in a common direction during simultaneous firing by an applied voltage. The desired output frequency is obtained by selectively polarizing and dimensioning the discs within the one or more disc assemblies. Each disc assembly is preferably disposed within an oil filled pressure housing that is pressure and temperature compensated. The axis of the at least one disc assembly can be parallel or perpendicular to the major axis of the logging tool.

Monopole acoustic transmitter comprising a plurality of piezoelectric discs

A method for determining concentrations of naturally occurring radioactive elements in earth formation by analysis of gamma ray energy spectra measured by at least one gamma ray detector while the borehole is being drilled. Gain of the gamma ray detector is controlled automatically through analysis of the spectra. The one or more gamma ray detectors are disposed at the periphery of the downhole instrumentation to maximize sensitivity. Elemental concentrations of naturally occurring radioactive elements such as potassium, uranium and thorium are measured either as a function of depth in the borehole, or as a function of aximuthal sectors around the borehole wall, or as a function of both depth and azimuthal sectors.

Spectral gamma ray logging-while-drilling system

A method and apparatus for formation testing is disclosed. In a preferred embodiment, a formation testing tool includes a longitudinal body with a flowbore; a plurality of extendable centralizing pistons coupled to the body; an extendable sample device coupled to the body; and a centralizing hydraulic circuit configured to cause each of the plurality of centralizing pistons to extend at substantially the same rate. The centralizing hydraulic circuit includes a series of flow control and pressure-determining valves configured to extend the centralizing pistons at substantially the same rate, and to help maintain stability in the hydraulic circuit in response to external pressures. In some embodiments, the extendable sample device is preferably configured to be recessed beneath a surface of the body in a first position and to extend beyond the surface in a second position. The extendable sample device is preferably extended to contact the borehole wall substantially normal to the wall, protecting the sample device from excessive bending moments and other excessive forces.

Method and apparatus for MWD formation testing

A method for manufacturing NMR measurement-while-drilling tool having the mechanical strength and measurement sensitivity to perform NMR measurements of an earth formation while drilling a borehole, and a method and apparatus for monitoring the motion of the measuring tool in order to take this motion into account when processing NMR signals from the borehole. The tool has a permanent magnet with a magnetic field direction substantially perpendicular to the axis of the borehole, a steel collar of a non-magnetic material surrounding the magnet, antenna positioned outside the collar, and a soft magnetic material positioned in a predetermined relationship with the collar and the magnet that helps to shape the magnetic field of the tool. Due to the non-magnetic collar, the tool can withstand the extreme conditions in the borehole environment while the borehole is being drilled. Motion management apparatus and method are employed to identify time periods when the NMR measurements can be taken without the accuracy of the measurement being affected by the motion of the tool or its spatial orientation.

Method and apparatus for nuclear magnetic resonance measuring while drilling

Logging-while-drilling gamma ray back scatter density system with elements configured to minimize material between sensor and the borehole environs, maximize shielding and collimation efficiency, and increase operational reliability and ruggedness. The system comprises a drill collar with a cavity in the outer wall, and an instrument package containing a sensor. The instrument package is disposed in the cavity and protrudes from the outer wall of the collar. Embodied as a density LWD system, the sensor consists of a gamma ray source and two detectors mounted within an instrument package framework made of high Z shielding material. A stabilized containing an alignment channel in the inner surface is disposed around the collar and receives the protrusion. The source and detectors are preferably positioned within the instrument package so that they fall within a radius defined by the outer surface of the collar. The source is threaded directly into the high Z material framework of the instrument package.

Logging-while-drilling apparatus and methods for measuring density

An NMR measurement-while-drilling tool having the mechanical strength and measurement sensitivity to perform NMR measurements of an earth formation while drilling a borehole, and a method and apparatus for monitoring the motion of the measuring tool in order to take this motion into account when processing NMR signals from the borehole. The tool has a permanent magnet with a magnetic field direction substantially perpendicular to the axis of the borehole, a steel collar of a non-magnetic material surrounding the magnet, antenna positioned outside the collar, and a soft magnetic material positioned in a predetermined relationship with the collar and the magnet that helps to shape the magnetic field of the tool. Due to the non-magnetic collar, the tool can withstand the extreme conditions in the borehole environment while the borehole is being drilled. Motion management apparatus and method are employed to identify time periods when the NMR measurements can be taken without the accuracy of the measurement being affected by the motion of the tool or its spatial orientation.

The present invention is directed to a downhole, high-current, low-impedance, feed-through connector for passing electrical current, preferably high frequency AC current, between a tool compartment having relatively high pressure and another tool compartment having relatively low pressure. The primary intended application of the present invention is to connect a radio frequency transmitter/receiver antenna to the antenna's tuning capacitors, but the present invention is applicable to any downhole application requiring the transmission of high electrical current across a barrier having a high pressure differential. This invention minimizes the force acting on the connector due to the high pressure differential by providing a conductor preferably having either a wave-like cross-section or a multi-finned cross-section, thereby minimizing the overall cross-sectional area of the connector yet providing sufficient cross-sectional area of the conductor to carry the necessary amount of electrical current.

High pressure differential electrical connector

A downhole drilling efficiency sensor (DES) apparatus for use with drilling operations in oil and gas exploration, that accurately measures important drilling parameters at or near the drill bit in order to increase the effectiveness and productivity of the drilling operation. The parameters measured include weight-on-bit (WOB), torque-on-bit (TOB), bending-on-bit (BOB), annulus pressure, internal bore pressure, triaxial vibration (DDS&mdash;drilling dynamics sensor), annulus temperature, load cell temperature, and drill collar inside diameter temperature or thermal gradient across such drill collar. The direction of the bending-on-bit measurement is also determined with respect to the low side of the hole while rotating (or stationary) by using a triaxial vibration sensor and magnetometer array. Each of the parameters are known to be important factors in determining the direction, rotation, and rate of drilling. The device described combines sensors capable of collecting all of the indicated parameters and presenting them to the drilling operator such that an accurate view of the downhole drilling parameters can be obtained.

Apparatus for measuring downhole drilling efficiency parameters

A stabilizer-type downhole tool comprises an elongate main body. At least one elongate blade lying generally longitudinally along the exterior of the main body projects radially outwardly therefrom. Attachment means cooperative between the main body and the blade removably retain the blade on the main body so as to permit limited relative longitudinal movement between one end of the blade and the adjacent portion of the main body without necessitating corresponding movement at the other end of the blade. The main body may comprise an instrument-receiving cavity beneath the blade, and an elongate instrument in a sealed housing may be disposed in the cavity, with its ends retained with respect to the adjacent portion of the main body without necessitating corresponding movement at the other end. At least one of the housing ends is so retained as to permit relative longitudinal movement with respect to the main body.

Growing community of inventors

Houston, TX, United States of America

Dale Allen Jones