Abstract: A capacitance probe for determining the water cut or the amount of water in fluids. The probe includes at least a pair of electrodes. Each electrode includes a thin, pliable and conductive winding. The windings have a thin insulation layer or coating. The first electrode and the second electrode are configured to form a capacitance sensor that generates a signal related to the dielectric permittivity of a fluid flowing between the first electrode and the second electrode.

Abstract: Methods and apparatus for determining the water cut or the amount of water in fluids. The apparatus is inserted into a production logging tool that is lowered into the well. The apparatus includes a conductive winding which is configured as a first electrode. The winding includes a thin insulation coating or layer. The body of the tool is configured as a ground electrode. The primary electrode and the ground electrode are configured to form a capacitance sensor that generates a signal related to the dielectric permittivity of a fluid flowing between the primary electrode and the ground electrode.

Abstract: A method for determining the fractional amounts of, and the thermal neutron capture cross-sections of, individual components which are included in the decay spectrum measured by a pulsed neutron well logging instrument. The instrument includes a pulsed high energy neutron source, and one or more gamma ray detectors spaced apart from the source. The method includes generating a data kernel which is made up of representors of decay components of the wellbore and of the earth formations in the vicinity of the instrument. The decay spectrum measured by the instrument is inverted to determine parameters by which the representors are scaled so that in combination the scaled representors most closely match the measured decay spectrum. The parameters represent the fractional amounts of each exponential decay component which makes up the measured exponential decay spectrum.

Abstract: This invention describes a methodology to image features using an array of multiple piezo-electric elements which employs the selective use of mechanical and electronic beam focusing, electronic beam steering and amplitude shading to increase resolution and overcome side lobe effects. This invention introduces a novel signal reconstruction technique utilizing independent array element transmission and reception, creating focusing and beam steering. Application of the methodology can be used in wireline, measurement while drilling, pipe and pipeline and medical applications. Applications include, but are not limited to Bore hole Caliper, Bore hole Geometry, Bore hole Imaging, Casing Inspection, Cement Evaluation and Volumetric Scanning Applications (e.g. Fluid, Behind Casing and Open Hole). The configuration of the transducer array is preferably cylindrical, but may be conical, biconical, convex, concave or may take the form of a number of suitable geometric configurations.

Abstract: The signal-to-noise ratio of televiewer signals from a rotary sidewall acoustic-beam scanner is improved by replacing the volume of borehole drill fluid that lies in the path of the acoustic beam with a solid medium characterized by a lower coefficient of attenuation than that of the drill fluid.

Abstract: The invention is an apparatus for increasing the signal amplitude of a piezoelectric acoustic transducer. A piezoelectric actuator is affixed to an arched spring which changes arched height in response to change in length of the actuator. The spring drives a rigid surface which can be directly coupled to a material which is to be acoustically energized. In a particular embodiment of the invention, the rigid surface is coupled to an hydraulic transmission. The output of the transmission is coupled to the material which is to be acoustically energized.

Abstract: A logging-tool assembly for generating both flexural wavefields and compressional wavefields in the sidewall formations encountered by a borehole. The assembly consists of a sonde constructed of a plurality of segments that are axially rotatable with respect to each other. Each one of two of the segments includes a compartment in which is mounted a dipole bender bar transmitting transducer. Two additional segments each contain one or more binaurally sensitive receiver transducers. Monopole transmitting and receiving transducers are also included in the respective appropriate segments. An acoustic isolator of novel construction acoustically separates the transmitting transducers from the receiving transducers.

Abstract: A new "radial" cement bond instrument is disclosed for measuring the quality of cement to casing bond. The instrument is capable of measuring the quality of the cement bond both vertically and circumferentially. Four arrays of sectored transmitters and receivers are arranged longitudinally along the instrument body and provide a compensated radial bond measurement with high azimuthal resolution. The sectored transmitter excites both a compressional wave and a shear wave in the casing, with the beam pattern of the transmitter focused in a radial direction. The sectored receiver provides additional directivity for enhanced detection of channels in cement. The disclosed apparatus provides measurement of the quality of cement bond in eight radial segments. The resolution of the instrument provides 5 to 10 percent overlap to insure "full" coverage of the borehole.

Abstract: A generalized computer-based system and method for acquisition of nuclear well logging data, including downhole generation of energy and time spectral information. A downhole instrument traverses a borehole introducing high energy neutrons into the formation at prescribed depths. Resultant gamma rays are detected and converted into pulses which are amplified and conditioned.A downhole multi-parameter analyzer stores pulse height and arrival time for each detected gamma ray whereby time and energy spectra are formed. Spectra include, alone or in combination, time spectra of the neutron source, inelastic and capture energy spectra. From the source time spectra, peaks are detected and capture and inelastic gates referenced thereto. Also thermal neutron decay between source bursts is derived. From the energy spectra peaks including hydrogen or iron are detected and used for calibration and automatic gain control of the gamma ray detector.

Abstract: A computer-based system and method for acquisition of nuclear well logging data, including downhole generation of energy and time spectral information. For acquiring energy spectrum data, a downhole multi-parameter analyzer is provided including a pulse height analyzer and memory. The analyzer converts each gamma ray pulse height into a digital code by peak detection, level and pulse pile-up discrimination, sample-and-hold, and analog-digital conversion. The digital code includes the address of a unique memory location or channel corresponding to the energy of the particular gamma ray. After a preselected time interval the memory channels collectively contain counts for each incremental energy band in the desired energy spectrum. The memory may then be interrogated by the downhole CPU for presentation of a gamma ray emission versus energy level plot. For acquiring temporal spectrum data, the multi-parameter analyzer also includes a memory address generator.

Abstract: A generalized computer-based system and method for acquisition of nuclear well logging data, including downhole generation of spectral information. A downhole instrument traverses a borehole introducing high energy neutrons into the formation at prescribed depths. Resultant gamma rays are detected and converted into pulses which are amplified and conditioned. For acquiring temporal spectral data, a multi-channel scale section is provided which includes a channel number generator which produces a numerical sequence of memory address codes corresponding to a sequence of adjacent time windows. Each code uniquely defines a start time, whereby the windows collectively comprise the time interval of the desired spectrum. Each time a gamma ray pulse is detected, the memory address generated at that time addresses a corresponding memory location and increments the count value resident therein.