摘要:
An acoustic logging tool emits a wideband acoustic pulse toward an inside surface of a borehole casing and an acoustic response is received. The acoustic response is analyzed at one or more higher order harmonics of the thickness mode resonance of the casing to determine the acoustic impedance of the material behind the casing.
摘要:
An acoustic logging tool emits a wideband acoustic pulse toward an inside surface of a borehole casing and an acoustic response is received. The acoustic response is analyzed at one or more higher order harmonics of the thickness mode resonance of the casing to determine the acoustic impedance of the material behind the casing.
摘要:
A bi-directional acoustic telemetry system is presented for communicating data and/or control signals between a first modem and a second modem along tubing. The system includes a communication channel defined by the tubing, a transducer of the first modem, and a transducer of the second modem. The transducer of each modem are configured to transmit and receive data and/or control signals, and are further configured to electrically communicate with a power amplifier characterized by an output impedance Zs and a signal conditioning amplifier characterized by an input impedance Zr. The system also includes a reciprocal response along the communication channel between the output impedance Zs and the input impedance Zr.
摘要:
The invention concerns an ultrasonic fluid counter including at least two ultrasonic transducers collectively defining an ultrasonic measuring path and emitting and receiving ultrasonic waves in the fluid along said ultrasonic measuring path according to at least one ultrasonic frequency, wherein attenuation means for attenuating parasitic ultrasonic waves generated outside said fluid counter and transmitted by the fluid according to the ultrasonic frequency or frequencies are associated with the fluid counter.
摘要:
A well casing is insonified with a first acoustic wave in a first mode that may be any mode of a set including: extensional mode, thickness mode, flexural mode. A first echo is received at a first acoustic transducer for receiving, a first signal is produced and a first measurement is extracted from the first signal. The casing is then insonified with a second acoustic wave in a second mode that may be any mode of the set of modes but is distinct from the first mode. A second echo is received at a selected second acoustic transducer for receiving and a second signal is produced. A second measurement is extracted from the second signal. The zone behind the casing of the well is evaluated from a combination of the first measurement and the second measurement.
摘要:
The invention provides a method for measuring and locating a fluid communication pathway in a material behind a casing wall, wherein said material is disposed in an annulus between said casing and a geological formation, and said method comprising: measuring a set of parameters of the material behind the casing within a range of radius, depths and azimuthal angles; defining sections comprising a sub-set of parameters wherein said sub-set of parameters is taken in said set of parameter for a given range of radius, depths and azimuthal angles included in said range of radius, depths and azimuthal angles; defining for each section a first limit zone and a second limit zone in frontier of said given range; determining among said sections the ones that comprise a continuous fluid communication pathway from said first limit zone to said second limit zone, said sections being renamed in retained sections; determining from said continuous fluid communication pathway an area or a width of pathway versus depth for each of said retained sections; extracting a fluid communication index versus depth for the material behind the casing, wherein said fluid communication index versus depth: depends of said area or width for retained sections and, is equal to zero for non retained sections; deducing from said fluid communication index the existence and location of fluid communication pathway in said material behind said casing wall.
摘要:
A surface mud pipeline system is described with a mechanical acoustic filter (1245) tuned to a predetermined frequency band so as to attenuate pump noise (132) within this band. The filter can be combined with a Venturi constriction to provide enhanced attenuation and is used to improve signal transmission of a mud pulse telemetry system (113-2).
摘要:
An acoustic transceiver assembly including a housing, an oscillator, and at least one membrane. The housing has at least one inner wall defining a cavity. The housing also has a first end and a second end defining an axis of the acoustic transceiver assembly. The oscillator is provided in the cavity. The oscillator is provided with a transducer element, and a backing mass acoustically coupled to the transducer element. The at least one membrane extends outward from the backing mass to support at least the backing mass within the cavity. The at least one membrane is flexible in an axial direction parallel to the axis of the acoustic transceiver assembly to permit the backing mass to oscillate in the axial direction, and rigid in a transverse direction to restrict lateral movement of the backing mass relative to the housing.
摘要:
The invention provides a method for estimating an impedance of a material behind a casing wall, wherein the casing is disposed in a borehole drilled in a geological formation, and wherein a borehole fluid is filling said casing, the material being disposed in an annulus between said casing and said geological formation, said method using a logging tool positionable inside the casing and said method comprising: exciting a first acoustic wave in said casing by insonifying said casing with a first pulse, the first acoustic wave having a first mode that may be one of flexural mode or extensional mode; receiving one or more echoes from said first acoustic wave, and producing a first signal; extracting from said first signal a first equation with two acoustic properties unknowns for respectively said material and said borehole fluid; exciting a second acoustic wave in said casing by insonifying said casing with a second pulse, the second acoustic wave having a thickness mode; receiving one or more echoes from said second acoustic wave, and producing a second signal; extracting from said second signal a second equation with said two acoustic properties unknowns; extracting the acoustic properties of said material behind the casing wall from said first and said second equations.
摘要:
The invention provides a method for estimating an impedance of a material behind a casing wall, wherein the casing is disposed in a borehole drilled in a geological formation, and wherein a borehole fluid is filling said casing, the material being disposed in an annulus between said casing and said geological formation, said method using a logging tool positionable inside the casing and said method comprising: exciting a first acoustic wave in said casing by insonifying said casing with a first pulse, the first acoustic wave having a first mode that may be one of flexural mode or extensional mode; receiving one or more echoes from said first acoustic wave, and producing a first signal; extracting from said first signal a first equation with two acoustic properties unknowns for respectively said material and said borehole fluid; exciting a second acoustic wave in said casing by insonifying said casing with a second pulse, the second acoustic wave having a thickness mode; receiving one or more echoes from said second acoustic wave, and producing a second signal; extracting from said second signal a second equation with said two acoustic properties unknowns; extracting the acoustic properties of said material behind the casing wall from said first and said second equations.