91 results about "Logging while drilling" patented technology

The invention discloses a while-drilling electromagnetic wave advanced detection sensitivity analysis method, and belongs to the field of oil-gas exploration and development. The method comprises the following steps: constructing a while-drilling electromagnetic wave advanced detection model, quantifying the influence of different measurement parameters on advanced detection signals, then analyzing the response characteristics of the advanced detection signals, extracting key sensitivity factors, and defining a single-parameter sensitivity function and a multi-parameter coupling sensitivity function; the sensitivity of advanced detection signals is qualitatively and quantitatively analyzed from the four angles of the distance to the interface, the formation resistivity, the interlayer and the stratigraphic dip angle, so that the while-drilling electromagnetic wave advanced detection range is optimized, and the adaptability in the well logging process is enhanced. And meanwhile, the advanced detection second-order sensitivity is approximately solved by adopting a central difference formula, influence factors suffered by advanced detection signals are analyzed from a numerical angle, the interaction of multi-parameter coupling is analyzed, and a scientific basis is provided for electromagnetic wave logging while drilling accurate inversion and instrument design.

The invention provides a petroleum drilling geomechanical characteristic estimation method based on deep learning, and aims to solve the problems of high measurement cost and poor real-time performance of shear wave velocity Vs in traditional geomechanical analysis by fusing logging while drilling LWD data and real-time drilling engineering parameters. According to the method, a Transformer model is adopted to carry out depth correction on logging-while-drilling data, depth offset of a drill bit and a logging sensor is eliminated, and real-time drilling parameters such as torque T, bit pressure WOB and drilling speed ROP are combined and input into a multi-layer perceptron MLP network to predict the shear wave speed Vs. And further calculating key geomechanical parameters based on the predicted shear wave velocity Vs. In practical application, the method improves the shear wave velocity prediction accuracy to 97.2%, the mean absolute error MAE of the shear modulus is reduced from 0.186 to 0.059, and the bulk modulus is reduced from 0.189 to 0.040. The method can be used for outputting stratum elastic parameters, optimizing bit pressure, pre-warning well wall instability and adjusting a well track, well drilling safety and efficiency are improved, and meanwhile dependence on an expensive well logging technology is reduced.

The invention discloses a rotary steerable drilling trajectory prediction method based on deep learning and knowledge distillation, and belongs to the technical field of drilling trajectory prediction, and the method comprises the following steps: collecting rotary steerable drilling site ground data and while-drilling well logging data, and carrying out data preprocessing; constructing a teacher model and training; the teacher model comprises a well drilling feature enhancement module and a sequence change prediction module; a teaching assistant model is constructed and trained, and the teacher model is assisted to carry out multi-interlayer data adaptive compression; a composite knowledge distillation framework and a student model are built, the student model is trained, and the trained student model is a lightweight borehole trajectory prediction model; during field application, ground data and logging-while-drilling data are preprocessed and then sent into the lightweight well track prediction model, a well track prediction value in the rotary steering drilling process is obtained, and therefore drilling operation parameters are adjusted in time according to a prediction result. According to the method, high-precision and light-weight well track prediction is realized.

The embodiment of the invention discloses a quality control method and device for logging-while-drilling data and computing equipment. The method comprises the following steps: acquiring actually measured signal values of different sampling orientations acquired by the electromagnetic wave logging-while-drilling instrument at a target depth; performing waveform fitting on the actually measured signal values of different sampling orientations to generate a waveform coefficient corresponding to the target depth; fitting signal values of different sampling directions are generated based on the waveform coefficients; extracting a waveform baseline from the waveform coefficient, processing the measured signal value by using the waveform baseline to obtain a corrected measured signal value, and processing the fitted signal value by using the waveform baseline to obtain a corrected fitted signal value; calculating a data error of the sampling orientation according to the corrected actual measurement signal value and the corrected fitting signal value of the sampling orientation; and generating a quality index value of the target depth according to the data errors of different sampling orientations at the target depth. According to the scheme, accurate quality detection and accurate control of the logging-while-drilling data can be achieved, and the subsequent logging data analysis accuracy is improved.

The present application relates to the field of logging while drilling and intelligent steering control technology in oil and gas drilling engineering, in particular to a rotary steering drilling adaptive trajectory control method for image processing. It comprises: receiving original logging while drilling image data frames of downhole transmission channels; generating a high-resolution predicted geological texture map; synchronously generating a feature uncertainty distribution map representing the pixel probability distribution characteristics in the high-resolution predicted geological texture map; calculating the matching degree of the high-resolution predicted geological texture map and a preset stress-induced artifact feature library; generating a sensor contamination marker signal; calling a safety baseline geological model constructed before drilling; calculating the geological texture structure difference value relative to the safety baseline geological model; generating a geological illusion entropy; receiving the geological illusion entropy and the sensor contamination marker signal; and driving a downhole steering tool according to the activated mode. The present application ensures that the steering instruction is always based on the real existing geological information, and avoids the deviation of the drilling trajectory caused by the fictitious texture.

The application discloses a downhole multi-parameter logging device and belongs to the technical field of logging while drilling, comprising a drill collar, a battery module and a circuit module are respectively arranged at the two ends of the inner cavity of the drill collar and are axially fixed through locking modules, a metal centralizer is fixedly arranged in the inner cavity of the drill collar, a plurality of independent centralizing blocks are arranged at the center of the metal centralizer, the drill collar comprises a drill collar body, an antenna housing, a strip-shaped magnetic core and a coil, and stable signal transmission is guaranteed, the battery module comprises annular batteries and butterfly springs, can be replaced on site and has a damping function, the circuit module comprises resistivity, azimuth gamma and inclination measurement modules, is integrally designed and has strong anti-interference performance, the metal centralizer realizes self-adaptive centralizing through centrifugal force and hydraulic damping, and the independent centralizing blocks can compensate temperature errors, the device is stable in structure, is suitable for complex well conditions, is convenient to maintain and can realize accurate and synchronous measurement of multiple parameters, thereby providing reliable data support for logging while drilling.

The invention provides a while-drilling radioactive logging system, a logging method and a drilling tool assembly, and belongs to the technical field of oil-gas exploration, and the system comprises at least one perovskite semiconductor detector which is used for directly absorbing gamma rays from a stratum and generating corresponding electric pulse signals; the electronics module is electrically connected with the perovskite semiconductor detector and used for processing the electric pulse signal to obtain while-drilling radioactive logging data, and the while-drilling radioactive logging data comprises at least one of natural gamma counting data, natural gamma energy spectrum data and gamma-gamma density data; the protection packaging body comprises a metal shock-resistant and high-pressure-resistant shell, a heat insulation and heat preservation layer and a heat channel which are arranged in the metal shock-resistant and high-pressure-resistant shell, and a high shock-resistant and impact-resistant connecting piece for fixing internal devices, and the protection packaging body is used for accommodating the perovskite semiconductor detector and the electronics module; and the safety and the accuracy of radioactive logging while drilling are improved.

The invention discloses a drilling risk prediction method based on geophysical data and related equipment. The method comprises the steps that geophysical parameters in the seabed drilling process are collected in real time through logging while drilling equipment; preprocessing the geophysical parameters to generate target logging data; the target logging data are constructed into a space sequence with the depth as the axis, and a dynamic extrapolation model is trained and generated by using a preset time sequence prediction algorithm based on the space sequence of the drilled stratum; inputting real-time target logging data into the dynamic extrapolation model, and predicting to obtain stratum parameters of an undrilled stratum within a preset distance in front of the drill bit; and coupling the stratum parameters with a preset geomechanical model to generate a dynamic safe drilling window containing a drilling parameter safe range. The method can effectively predict front geological anomalies, remarkably improves the safety and operation efficiency of seabed oil and gas drilling, and can be widely applied to the technical field of seabed oil and gas resource exploration and development.

The present disclosure relates to a method and device for identifying tectonic coal based on borehole gamma data. The method comprises: acquiring gamma curve data and mechanical drilling speed data collected in real time during the process of logging while drilling; preprocessing the gamma curve data and the mechanical drilling speed data to obtain depth sequence data; performing segmentation processing on the depth sequence data to obtain a plurality of data sample units; for each data sample unit, extracting a plurality of sample features for representing the response mode of tectonic coal from the data sample unit, fusing the plurality of sample features to obtain a multi-parameter fusion feature vector; and inputting the multi-parameter fusion feature vector into a trained machine learning classification model to obtain a classification result output by the machine learning classification model. The present scheme improves the accuracy and efficiency of tectonic coal identification.

This utility model discloses a remote gamma measurement device for logging while drilling. The remote gamma measurement device includes: a pressure-resistant cylinder, a mounting frame, a main control and power board, a gamma sensor, a metal shielding sleeve, a shielding layer, a first connector assembly, and a second connector assembly. The mounting frame is located inside the pressure-resistant cylinder; the main control and power board is located on the mounting frame; the gamma sensor is located on the mounting frame and electrically connected to the main control and power board, and the gamma sensor includes a photomultiplier tube and a NaI crystal; the metal shielding sleeve is fitted over the photomultiplier tube; the shielding layer is located inside the pressure-resistant cylinder and is used to shield the peripheral area of ​​the gamma sensor; the first connector assembly is located on the pressure-resistant cylinder and electrically connected to the main control and power board; the second connector assembly is located on the pressure-resistant cylinder and electrically connected to the gamma sensor. This utility model's remote gamma measurement device for logging while drilling can reduce the influence of external signals on the photomultiplier tube and improve the reliability of the remote gamma measurement device for logging while drilling.

The application discloses a titanium-copper alloy pipe and a preparation method thereof. The titanium-copper alloy pipe comprises the following components in mass percent: Ti: 2.3-3.4%, Cr: 0.02-0.2%, Ni: 0.02-0.5%, Al: 0.15-0.20%, rare earth elements: 0-0.05%, the rare earth elements being at least one of Ce, La, Sc and Y, the balance being Cu and inevitable impurities, and Cu+Ti≥96.0%. The preparation method comprises the following steps: titanium-copper ingot casting, homogenization heat treatment, hole drilling and breaking down, pickling, quenching, rolling, aging hardening treatment, nondestructive testing, water pressure detection, wall thickness measurement and the like. The titanium-copper alloy pipe has a tensile strength of 1100-1250 MPa, a yield strength of 1050-1100 MPa, an elongation after fracture of ≥7.0%, and a hardness HRC of 38-42, and meets the requirements of the strength and corrosion resistance of a pressure-resistant outer cylinder for a logging-while-drilling device.

Embodiments of the application disclose a method and device for quality control of logging-while-drilling data and a computing device. The method comprises: obtaining measured signal values of different sampling directions collected by a logging-while-drilling electromagnetic wave logging instrument at a target depth; performing waveform fitting on the measured signal values of different sampling directions to generate waveform coefficients corresponding to the target depth; generating fitted signal values of different sampling directions based on the waveform coefficients; extracting a waveform baseline from the waveform coefficients, processing the measured signal values using the waveform baseline to obtain corrected measured signal values, and processing the fitted signal values using the waveform baseline to obtain corrected fitted signal values; calculating data errors of the sampling directions according to the corrected measured signal values and the corrected fitted signal values of the sampling directions; and generating a quality index value of the target depth according to the data errors of different sampling directions at the target depth. The method can achieve accurate detection and control of the quality of logging-while-drilling data and improve the accuracy of subsequent logging data analysis.

The invention relates to the technical field of logging while drilling, and discloses a stratum simulation box for a lateral resistivity logging while drilling tool and a design method of the stratum simulation box. The design method comprises the following steps: determining an electrode structure of an azimuth electrode system of the lateral resistivity logging-while-drilling tool; determining a resistance network of the stratum simulation box based on an electrode structure and a working principle of the azimuth electrode system; according to the resistance network of the stratum simulation box and a working principle, determining a calculation scheme of each resistance parameter in the resistance network of the stratum simulation box; and determining each resistance value of the stratum simulation box resistance network under the typical stratum condition by utilizing a three-dimensional finite element program. The formation simulation box for the while-drilling lateral resistivity logging instrument is designed and generated through the method, various formations simulated by the formation simulation box can be measured by the while-drilling lateral resistivity logging instrument indoors, the working state of the instrument can be checked conveniently, and the instrument can be debugged, maintained and calibrated conveniently; and the time for repeatedly testing and verifying the performance of the instrument is greatly saved.

This invention discloses a cross-well shear wave velocity prediction method based on GR lithology bin alignment. Addressing the problems of large inter-well lithological differences, inconsistent engineering parameter distributions, and insufficient utilization of multi-source features in existing cross-well prediction methods, this method first collects drilling engineering parameters and logging data from multiple wells. After preprocessing, the data is divided into training and test sets using the well retention method. The optimal GR lithology bin alignment strategy is selected from the training set to achieve inter-well lithology alignment. Based on this, the absolute and relative deviation characteristics of engineering parameters are calculated, and drilling logging features such as P-wave transit time and density are integrated to construct a complete prediction feature set. Finally, the LightGBM regression algorithm is used to establish a cross-well shear wave velocity prediction model, which is optimized using an early stopping mechanism before outputting the prediction results. Practical application shows that the coefficient of determination R0 is significantly improved. 2 The accuracy reached 0.91, which is more than 18% higher than that of traditional modeling methods, and can effectively achieve high-precision and rapid prediction under the condition of no shear wave logging in new wells.

The high-temperature turbine generator comprises a shell in threaded connection with the measurement and control instrument while drilling, one end of the shell is connected with a stator, a generator rotating shaft is rotatably arranged in the shell, one end of the generator rotating shaft is sleeved with an inner magnetic coupling cylinder, a rotor is rotatably arranged outside the stator, and the rotor is sleeved with an outer magnetic coupling cylinder. A turbine blade is arranged on the outer side of the rotor, an outer magnetic coupling barrel is embedded in the rotor and corresponds to the inner magnetic coupling barrel in position, the other end of the generator rotating shaft is sleeved with a barrel type power generation magnetic field, and a barrel type power generation coil is arranged on the inner side of the shell and corresponds to the barrel type power generation magnetic field in position. The utility model relates to the technical field of petroleum drilling and well logging while drilling, adopts sealed permanent magnet excitation, performs power generation by washing turbine blades through slurry, and has the advantages of compact structure, small size, capability of lengthening a barrel type power generation coil in an axial space to meet different power requirements, good adaptability and high reliability. The power supply device is especially suitable for power supply of the logging-while-drilling instrument for deep wells and small-size holes.

This invention relates to an ultrasonic sensor and a logging-while-drilling (LWD) instrument. The ultrasonic sensor includes a base detachably connected to the drill collar of the LWD instrument. The base has a sealed pressure balancing chamber and an ultrasonic probe mounting chamber. The pressure balancing chamber is filled with pressurized oil to balance the mud pressure. An ultrasonic probe is positioned within the ultrasonic probe mounting chamber. The pressure balancing chamber and the ultrasonic probe mounting chamber are connected via an oil passage. The base also has a pressure-bearing pin mounting chamber isolated from the mud. A pressure-bearing pin is positioned within the pressure-bearing pin mounting chamber. The ultrasonic probe mounting chamber and the pressure-bearing pin mounting chamber are connected via a wire passage, which contains a wire connecting the ultrasonic probe and the pressure-bearing pin. This invention ensures pressure balance within the ultrasonic sensor under high temperature and high pressure conditions, thus improving the service life of the ultrasonic probe.

The invention discloses a thickened oil drilling and exploiting system based on an intelligent coiled tubing and a drilling and exploiting method thereof.The thickened oil drilling and exploiting system comprises a coiled tubing assembly and a thickened oil exploiting unit, and the thickened oil exploiting unit is arranged at the lower end of the coiled tubing assembly; a drilling monitoring assembly, a hydraulic control pipeline, a first power supply control cable and a second power supply control cable are arranged on the outer side wall of the coiled tubing assembly, and a well logging while drilling drill collar unit is arranged at the lower end of the thickened oil recovery unit; the continuous oil pipe has the function of becoming an oil extraction pipe column for exploiting thickened oil, large-scale production of thickened oil resources can be achieved, and the function of continuously measuring the acoustic velocity, density, resistivity and radioactive parameters of stratum rocks around the electric drill bit in real time in the drilling process is achieved. And the function of monitoring the recovery condition of the underground heavy oil resources and the distribution state of the residual heavy oil resources around the well in real time is achieved, the recovery efficiency of the heavy oil resources is improved, and the method is suitable for being widely popularized and used.

A vibration measurement system and method for logging while drilling, belonging to the field of oil and gas drilling engineering technology and equipment, includes: a microcontroller for acquiring acceleration signals detected by an accelerometer, processing the data, and storing it in a Flash memory module, and communicating with a host computer via a communication interface; a power supply module for powering the entire system; an accelerometer for measuring the vibration experienced by the drilling equipment during logging while drilling and transmitting the detected acceleration signals to the microcontroller; a Flash memory module for storing the measured acceleration data and other important information; and a communication interface for enabling data communication between the microcontroller and the host computer. This invention allows for use in high-temperature drilling environments, expanding the system's application range; it possesses sufficient stability and anti-interference capabilities, effectively coping with complex downhole environments; and it enables efficient and stable data storage and transmission.

The application discloses a mechanical drilling speed prediction method based on micro-inclination characteristics, comprising the following steps: acquiring real drilling wellbore logging while drilling and logging data as a first data set; preprocessing the first data set and extracting the best feature and the micro-inclination feature as input features; the preprocessing comprises data cleaning and correlation analysis; training a mechanical drilling speed prediction model by using the input features; and predicting the mechanical drilling speed of a target well by using the trained mechanical drilling speed prediction model. The micro-inclination feature introduced in the application can significantly improve the ROP prediction accuracy of the model. By introducing the micro-inclination feature in the MLP neural network, the model weight is optimized, and the prediction accuracy of the ROP is improved. By introducing the micro-inclination feature in the SVR model and selecting the optimal hyperparameter, the prediction effect is significantly improved. The method provides a new idea for improving drilling parameter prediction and control by using machine learning, and can be applied to the optimization of drilling speed and efficiency.

This invention discloses a method for detecting the location of casing wells based on ultra-deep electromagnetic logging while drilling, belonging to the field of oil and gas field development. The method includes the following steps: s1, selecting and determining the use of ultra-deep harmonic anisotropic attenuation (UHAA) signals for casing well location detection; s2, creating a chart showing the relationship between the casing well location and the UHAA signal; s3, establishing the relationship between single-point response and casing well location; s4, selecting single-point or multi-point determination methods based on field conditions to obtain the UHAA signal, and then preliminarily determining the casing well location and its azimuth angle based on s2 and s3; s5, performing layered formation influence correction and wellbore non-parallelism influence correction on the casing well location and azimuth angle preliminarily determined in s4, ultimately determining the precise location and azimuth angle of the casing well. This invention can accurately determine the location of casing wells, providing important support for horizontal well neighbor well identification and collision prevention monitoring in oil and gas field development.

A drilling system performs a method for identifying a reservoir in a formation. The processor measures a first dielectric constant of the formation at a selected depth or depth interval using a first electromagnetic wave or signal emitted through the formation at the selected depth or depth interval in a borehole in the formation at a first frequency; measuring a second dielectric constant of the formation at a selected depth or depth interval using a second electromagnetic wave or signal emitted through the formation at a second frequency at the selected depth or depth interval in the borehole in the formation; and identifying a reservoir in the formation based on the first dielectric constant at the selected depth or depth interval and the second dielectric constant at the selected depth or depth interval.

A trajectory and reservoir relationship determination method and device based on entry and exit layer feature recognition, the method comprising: classifying and counting basic data according to angle difference values to obtain a first feature set; simulating a drill bit entering and exiting a layer by using a geological model to obtain drilling parameters at the entry and exit layer time, and performing regression calibration processing on the measurement-while-drilling and logging data corresponding to the entry and exit layer time to obtain a second feature set; performing model correction processing on the geological model by using the first feature set and the second feature set; simulating the drill bit entering and exiting the top and bottom of the target layer at different angle differences by using the corrected geological model to obtain drilling parameters, logging-while-drilling and logging data, and performing logging-while-drilling and logging data conversion calibration processing to obtain a third feature set; obtaining measured data, and performing trajectory adjustment processing on the measured data by using the third feature set to complete trajectory optimization. The present application performs trajectory optimization adjustment in advance, improves the reservoir drilling effect, and has a broad application prospect.

An earth-boring tool system may include a drill string and at least one or more sensors. The earth-boring tool system may receive field drilling data, logging while drilling (LWD) data, and data indicative of wear of at least part of a drilling tool, train a predictive bit wear model based on the received data, fit a wear trajectory regression curve to a latent space representation of the received data, and generate one or more predicted dull states of the at least one drilling tool based, at least in part, on the predictive bit wear model and the wear trajectory regression curve. The earth-boring tool system may also generate one or more similarity scores responsive to comparing the first drilling data to target data and filter the first drilling data or a latent space representation of the first drilling data responsive to the one or more similarity scores.

The invention relates to the technical field of oil exploration and development, and discloses a gamma logging curve correction and prediction method based on federal cross-domain collaboration. Aiming at the problems that traditional prediction depends on single-oil-field data, data scarcity and privacy leakage, historical logging-while-drilling data of multiple oil fields are collected and preprocessed, and a gamma logging curve is corrected in combination with the distance between a drill bit and a sensor; a time sequence prediction model based on a self-attention mechanism is constructed, a federated learning framework is established, and a parameter strategy is initialized; and respectively training a global model and a local model, and comparing and determining a final model through index evaluation such as a relative error. According to the method, on the premise that data privacy is protected, the gamma logging curve prediction precision is improved through the cross-oil-field data, and the real-time geological modeling requirement is met.

The invention belongs to the technical field of petroleum and natural gas exploration and development, and particularly relates to a method for judging a bottom interface of a permian stone thousand peak group by applying element logging data, which comprises the following steps: S1, collecting logging rock debris while drilling; s2, performing coarse division on the bottom interface of the permian stone thousand-peak group by combining regional deposition characteristics and geological design information, and delimiting a coarse division interface; s3, performing X-ray fluorescence spectrum scanning on the logging rock debris while drilling to obtain strontium, copper and barium element data; s4, carrying out data processing, analysis and judgment on the strontium, copper and barium element data, and calculating an interface coefficient JM; and S5, correcting the depth of the coarse interface to obtain the bottom interface depth of the permian stone thousand-peak group. According to the method for judging the bottom interface of the permian stone thousand peak group by applying the element logging data, errors existing in a lithology combination judgment method which mainly depends on naked eyes of technicians to recognize rock debris are corrected, and the method has the advantages of being small in error, small in data processing amount, high in accuracy, low in cost, easy to operate and wide in application range.

The application discloses a downhole communication system and an implementation method thereof, which is used for realizing communication of logging-while-drilling equipment and rotary steering tool hanging connection, and comprises a single bus, a first type of hanging connection equipment hung on the single bus and used for occupying the single bus by using a first communication protocol, wherein data collected by the hanging connection equipment from different communication protocols is obtained in a preset complete communication period, a second type of hanging connection equipment hung on the single bus and used for occupying the single bus by using a second communication protocol, and a communication circuit hung on the single bus and used for transmitting the data collected by the second type of hanging connection equipment to the first type of hanging connection equipment through time-sharing communication with the hanging connection equipment of different communication protocols, wherein the hanging connection equipment with different communication protocols does not occupy the single bus at the same time at the same time. The application improves the hanging connection efficiency of the logging-while-drilling equipment and the rotary steering tool.

This invention discloses an integrated logging-while-drilling (LOD) and measurement drill string assembly, relating to the field of oil and gas drilling engineering technology. It provides a series connection scheme for core protective drill string components, offering two switchable configurations: one with a mud motor and one without. Both configurations consist of an azimuth density neutron logging sub, a bidirectional communication power supply sub, an acoustic logging sub, a resistivity logging sub, an upper connecting sub, a flexible sub, a lower connecting sub, an azimuth gamma logging sub, and a steering actuator connected in series according to a fixed logic. The configuration with a mud motor only requires adding a mud motor at a designated location to complete the structural switch, without changing the series connection of the remaining subs. This assembly scheme is applicable to various drilling scenarios such as offshore exploration and development, deepwater drilling, complex directional wells, highly deviated wells, and horizontal wells. It enables integrated operations of geological steering, formation evaluation, and wellbore stability analysis during drilling, effectively improving drilling efficiency and reducing operational risks.

The application discloses a magnetic suspension type logging while drilling short section and belongs to the technical field of oil and gas exploration and development equipment. The application comprises an execution module, a logging module and a power management module. The execution module is used for generating a magnetic field which can suspend the logging short section. The logging module is used for collecting, receiving, transmitting and storing logging data and controlling the magnetic field. The power management module is used for supplying power to the above-mentioned parts and controlling the magnetic field as an actuator. The application can avoid the logging short section from contacting the drill pipe, greatly relieve the influence of vibration on the logging short section and improve the service life of the logging short section. The application can also complete the dynamic position adjustment of the logging short section inside the drill pipe, keep the logging short section and the drill pipe relatively static and keep the logging short section stable for logging operation.

The application discloses a segment cluster optimization design method based on geological guidance mechanical specific energy intelligent correction, which comprises the following steps: determining a target stable point set according to a multi-scale local stability index in each lithologic segment, wherein the lithologic segment is obtained by performing lithologic layer clustering on logging-while-drilling data and corresponding well depth data along a horizontal well segment; in each lithologic segment, performing layer-by-layer correction on original mechanical specific energy according to a mechanical specific energy median of the target stable point and / or a mechanical specific energy prediction result, wherein the mechanical specific energy prediction result is obtained based on the target stable point set; dividing a fracturing segment according to a geological sweet spot label and corresponding well depth data; in the fracturing segment, formulating a cluster distribution strategy according to the layer-by-layer corrected mechanical specific energy and the geological sweet spot label, and optimizing design of a perforation cluster based on the cluster distribution strategy. The application can accurately, efficiently and at low cost correct the mechanical specific energy, so that the accuracy and practicability of the fracturing segment cluster optimization design can be improved based on the corrected mechanical specific energy.

An ultrasonic transducer for use in a downhole wellbore environment is disclosed. The ultrasonic transducer can utilize a piezoelectric element located in a housing comprising an inner housing and an outer housing separated by an air gap. The air gap functions to block undesirable ultrasonic waves from exiting or being received by the ultrasonic receiver and resulting in signal noise. For example, the air gap can prevent ultrasonic waves generated by the piezoelectric element from exiting the housing through a side or rear thereof, and can prevent reflected ultrasonic waves from being received by the ultrasonic transducer through a side or rear of the housing. The air gap may contain a gas or a fluid, or the air gap may be evacuated. The ultrasonic transducer may be a component of a downhole tool, such as a logging-while-drilling tool, or a post-drilling operation tool, such as a wireline tool.