Abstract: A near-bit wireless constant current short-distance transmission device has an emission part and a receiving part. The emission part modulates a signal and then wirelessly transmits the modulated signal to the receiving part. The emission part transmits an emission signal into a stratum according to a set rated emission constant current value, and dynamically monitors and adjusts the rated emission constant current value of the emission signal to obtain stable emission power.

Abstract: In a method for synchronizing acoustic asynchronous serial signals while drilling, communication and high-voltage signal isolation between a transmitting terminal and a receiving master control board are realized in an asynchronous serial communication way. The receiving master control board serving as a master control terminal configures parameters for the transmitting terminal in the asynchronous serial communication way and controls the excitation of a sound source. The transmitting terminal is a synchronous sound source excitation signal initiator; signal synchronization is realized under an asynchronous communication condition due to the coordination of the transmitting terminal and the receiving master control board; the transmitting terminal includes a plurality of transmitting boards, and asynchronous serial communication between each of the transmitting boards and the receiving master control board is realized through two data lines R+ and R.

Abstract: In a method for synchronizing acoustic asynchronous serial signals while drilling, communication and high-voltage signal isolation between a transmitting terminal and a receiving master control board are realized in an asynchronous serial communication way. The receiving master control board serving as a master control terminal configures parameters for the transmitting terminal in the asynchronous serial communication way and controls the excitation of a sound source. The transmitting terminal is a synchronous sound source excitation signal initiator; signal synchronization is realized under an asynchronous communication condition due to the coordination of the transmitting terminal and the receiving master control board; the transmitting terminal includes a plurality of transmitting boards, and asynchronous serial communication between each of the transmitting boards and the receiving master control board is realized through two data lines R+ and R.

Abstract: The present invention discloses a device for performing temperature correction on an induction logging tool and deep stratum environmental simulation, including: a box body, configured to accommodate the induction logging tool and a deep stratum environmental simulation system; an air channel, configured to make heated air fill the box body; a circulating fan, configured to make the heated air enter the air channel; an electric heater, configured to heat air; a temperature controller, configured to control power of the electric heater; the deep stratum environmental simulation system, configured to simulate lithological and fluid situations in different stratum environments; a data collection system, configured to collect, store, process, and display a signal in real time; and a control unit, configured to control operation of the entire device.

Abstract: Disclosed is a magnetotelluric measurement system, comprising: a magnetic sensor probe for collecting an electromagnetic signal as an impulse response of an earth and transmitting the same to a signal readout circuit; the signal readout circuit configured for receiving and amplifying the electromagnetic signal collected by the magnetic sensor probe; a data acquisition and processing module configured for receiving and processing electromagnetic signal amplified by the signal readout circuit; a storage module configured for storing the electromagnetic signals amplified by the signal readout circuit and processed by the data acquisition and processing module; a first casing for enclosing the magnetic sensor probe and the signal readout circuit; and a second casing for enclosing the data acquisition and processing module and the storage module.

Abstract: The disclosure relates to the field of drilling tool attitude measurement, and particularly to a dynamic testing device suitable for a drilling tool attitude measurement module. The dynamic testing device may comprise a test fixture for attitude measurement module, an azimuth rotation device for adjusting an azimuth angle, an inclination angle swing device for adjusting an inclination angle, and a toolface angle rotation device for driving the test fixture for attitude measurement module to rotate, and a rotation speed measurement device for measuring a rotation speed and a self-rotation angle of the test fixture for attitude measurement module in a rotating state. The testing device has characteristics of large bearing weight, high rotation speed which is measurable and controllable, convenient for mounting and fixing a tested module, etc. It can simulate conditions of downhole rotation of a drilling tool, and be used for dynamic testing of the attitude measurement module.

Abstract: A near-bit constant-power wireless short-distance transmission apparatus includes a transmitting portion and a receiving portion. The transmitting portion is connected to a near-bit measurement sub while the receiving portion is connected to a measurement while drilling system. The transmitting portion processes data received by the bit measurement sub and then transmits it to the receiving portion. The receiving portion further processes the information and then transmits it to the measurement while drilling system. An insulating sub is inserted in the transmitting portion and separates the transmitting portion into a transmitting positive pole and a transmitting negative pole, which become electrically isolated from each other. Another insulating sub is inserted in the receiving portion and separates the receiving portion into a receiving positive pole and a receiving negative pole, which become electrically isolated from each other.

Abstract: An azimuthal acoustic LWD apparatus is sequentially provided with a centralizer, a transmitting circuit, transmitting transducers, an acoustic insulator, a receiving transducer array, ultrasonic transducers and a receiving circuit on a drill collar. The azimuthal acoustic LWD apparatus is capable of operating in a dipole mode or a unipole mode, to cover all the sectors around a wellbore by adopting a fixed time interval measurement mode or an alternating time interval measurement mode according to a relationship of an interval between measurement times and a rotation speed of the apparatus, thereby achieving azimuthal acoustic LWD. This apparatus overcomes problems that the fixed time interval measurement mode may not cover all the sectors and further may not achieve azimuthal acoustic imaging in a case where the rotation speed and the interval between measurement times are under certain conditions.

Abstract: An azimuthal acoustic LWD apparatus is sequentially provided with a centralizer, a transmitting circuit, transmitting transducers, an acoustic insulator, a receiving transducer array, ultrasonic transducers and a receiving circuit on a drill collar. The azimuthal acoustic LWD apparatus is capable of operating in a dipole mode or a unipole mode, to cover all the sectors around a wellbore by adopting a fixed time interval measurement mode or an alternating time interval measurement mode according to a relationship of an interval between measurement times and a rotation speed of the apparatus, thereby achieving azimuthal acoustic LWD. This apparatus overcomes problems that the fixed time interval measurement mode may not cover all the sectors and further may not achieve azimuthal acoustic imaging in a case where the rotation speed and the interval between measurement times are under certain conditions.

Abstract: In an apparatus for multi-pole acoustic logging while drilling, a N-cycle sinusoidal wave signal is generated by utilizing a signal processor, and amplified into a high-voltage sinusoidal excitation signal by utilizing a power amplifier, and output to a transmitting transducer. The signal processor simultaneously generates an enable signal. The enable signal includes a transient discharge enable signal. The power amplifier is connected with a transient discharge circuit. After the signal processor generates N cycles of a sinusoidal wave, the transient discharge enable signal enables the transient discharge circuit to discharge to release an energy storage current of a power transformer so as to eliminate a high-voltage ringing effect and improve an excitation efficiency of the transducer.

Abstract: Disclosed is a magnetotelluric measurement system, comprising: a magnetic sensor probe for collecting an electromagnetic signal as an impulse response of an earth and transmitting the same to a signal readout circuit; the signal readout circuit configured for receiving and amplifying the electromagnetic signal collected by the magnetic sensor probe; a data acquisition and processing module configured for receiving and processing electromagnetic signal amplified by the signal readout circuit; a storage module configured for storing the electromagnetic signals amplified by the signal readout circuit and processed by the data acquisition and processing module; a first casing for enclosing the magnetic sensor probe and the signal readout circuit; and a second casing for enclosing the data acquisition and processing module and the storage module.

Abstract: In a system for arranging survey points in field operation with a ground electromagnetic instrument, the position information of survey lines and survey points are planned and downloaded to an aircraft in advance. The survey lines and one survey point among survey points planned in advance is selected and the coordinate information of the survey point is acquired. The aircraft is controlled to fly to the physical geographic location of the survey point according to the coordinate information of the survey point in conjunction with positioning information acquired in real time. The aircraft hovers above the physical geographic location of the survey point and projects a predetermined indication mark to the ground. The detection instrument and electric field sensor are deployed at a first position indicated by the indication mark, and the magnetic field sensor is deployed at a second position; such a process is repeated till all of the planned survey points are arranged.

Abstract: A apparatus for downhole near-bit wireless transmission includes a bit connecting housing, a mud motor connecting housing, an insulating sub made of an insulating material. The insulating sub is serially connected between the bit connecting housing and the mud motor connecting housing to electrical insulate the bit connecting housing and the mud motor connecting housing from each other. The bit connecting housing and the mud motor connecting housing respectively form an electromagnetic transmitting positive pole and an electromagnetic transmitting negative pole. The mechanical apparatus further includes measurement units, which are configured to acquire parameters measured near the bit and a data transmitting unit, which is configured to realize wireless transmission; and the data transmitting unit is configured to receive and transmit the parameters measured near the bit.

Abstract: The present disclosure relates to the technical field of acoustic logging while drilling, and provides an integral packaging device for acoustic receiving transducers while drilling, wherein, the receiving transducers are directly arranged in a signal processing circuit, which is installed in an internal supporting frame fitted in a rectangular bellow; one side of the bellow has a deformable surface that is of a corrugated structure, and oil is filled in the bellow; the receiving transducers are arranged on the side that has a deformable surface; a shock absorbing rubber piece is of a U-shaped structure; one end of a connecting unit is connected to the signal processing circuit, and the other end of the connecting unit is connected to a main control circuit in a logging while drilling instrument. The present disclosure employs an integral packaging structure, which is easy to install structurally.

Abstract: An azimuthally acoustic imaging logging while drilling (LWD) apparatus employs two sets of transmitting transducers to excite multipole mode waves. One set is high-frequency monopole and polarized pole transmitting transducers, and the other set is low-frequency dipole and quadrupole transmitting transducers. Separation of a high-frequency transmitting state from a low-frequency transmitting state is realized by using a dual-row transmission solution. Each set of transmitting transducers operates at transducer resonance points through a matching circuit, thereby greatly increasing the transmitted energy.

Abstract: An acoustic source testing apparatus of an azimuthally acoustic logging while drilling (LWD) instrument includes a water tank, a silicone oil, a drill collar, an azimuthally acoustic while drilling quadrupole transmitting apparatus and an acoustic signal reception apparatus. The bottom of the water tank is symmetrically provided with two supporting columns, the drill collar is disposed in U-shaped grooves on the supporting columns, the azimuthally acoustic quadrupole LWD transmitting apparatus and the acoustic signal reception apparatus are disposed on the drill collar, the silicone oil is filled in the water tank, and the drill collar, the azimuthally acoustic quadrupole LWD transmitting apparatus and the acoustic signal reception apparatus are completely covered in the silicone oil.

Abstract: A near-bit dynamic well deviation angle measurement apparatus includes a circuit board and 2n+1 accelerometers. One accelerometer is installed in an axial direction of a drilling tool and forms n sets of three-axis orthogonal installation together with other 2n accelerometers. The accelerometer installed in the axial direction measures Az?, and the remaining accelerometers respectively measure n X-axis radial components and n Y-axis radial components corresponding to the n X-axis radial components. A filter and a data processing unit are integrated on the circuit board. The circuit board acquires signals in which the components are eliminated by the accelerators in real time, and further high-frequency vibration and impact interference in the signals are filtered out by using the filter to obtain non-interference gravitational acceleration components Ax, Ay and Az, and further a well deviation angle is calculated.

Abstract: The present disclosure relates to the technical field of acoustic logging while drilling, and provides an integral packaging device for acoustic receiving transducers while drilling, wherein, the receiving transducers are directly arranged in a signal processing circuit, which is installed in an internal supporting frame fitted in a rectangular bellow; one side of the bellow has a deformable surface that is of a corrugated structure, and oil is filled in the bellow; the receiving transducers are arranged on the side that has a deformable surface; a shock absorbing rubber piece is of a U-shaped structure; one end of a connecting unit is connected to the signal processing circuit, and the other end of the connecting unit is connected to a main control circuit in a logging while drilling instrument. The present disclosure employs an integral packaging structure, which is easy to install structurally.

Abstract: In an apparatus for multi-pole acoustic logging while drilling, a N-cycle sinusoidal wave signal is generated by utilizing a signal processor, and amplified into a high-voltage sinusoidal excitation signal by utilizing a power amplifier, and output to a transmitting transducer. The signal processor simultaneously generates an enable signal. The enable signal includes a transient discharge enable signal. The power amplifier is connected with a transient discharge circuit. After the signal processor generates N cycles of a sinusoidal wave, the transient discharge enable signal enables the transient discharge circuit to discharge to release an energy storage current of a power transformer so as to eliminate a high-voltage ringing effect and improve an excitation efficiency of the transducer.

Abstract: In a method for acquiring data of azimuthal acoustic LWD, when an acoustic LWD instrument rotates with a drilling tool at a certain depth, data is acquired by adopting an azimuthal equal-interval mode: a well circumference is divided into m sectors by azimuthal intervals ??, when a toolface angle of the acoustic LWD instrument is located in the kth sector, an acoustic transmitting source is controlled to transmit an acoustic signal, and an acoustic receiver measures the acoustic signal, digitizes it and then stores it as data in the kth sector; and the data is acquired for each sector in turn, and after the data is acquired in each sector for N times, the data acquisition at the current depth is completed. Meanwhile, as the drilling tool rotates and drills, the instrument acquires acoustic data at different depths and processes it to achieve azimuthal acoustic imaging.