China University of Petroleum

Sihui Luo

Guangzhi Liao

Lizhi Xiao

Xin Li

Zhe Sun

Wei Liu

Jie Wang

Weiliang Chen

Qunjie Du

Feng Deng

Kuntie Liao

Zhengduo Wang

Yongheng Fan

A nuclear magnetic resonance coil array and a decoupling method thereof, and a nuclear magnetic resonance detection device. The coil array includes: a coil resonant unit and a decoupling network unit, where the coil resonant unit includes multiple coil resonant circuits; the decoupling network unit includes multiple decoupling circuits; where a coil resonant circuit includes a coil and a resonant capacitor; the resonant capacitor in each coil resonant circuit is connected in parallel with the coil; the coils in each coil resonance circuit are equally spaced on a circumference; a decoupling circuit is provided between a positive terminal and a negative terminal of adjacent coils, respectively; each coil is connected to an antenna switching circuit of a nuclear magnetic resonance detection device at the same time.

Nuclear magnetic resonance coil array and decoupling method thereof, and nuclear magnetic resonance detection device

The application provides a downhole three-dimensional scanning nuclear magnetic resonance imaging logging instrument and a probe, an antenna thereof, wherein the antenna comprises: an radio frequency antenna, an orienting device and a rotating device; the radio frequency antenna is fixed on an outer surface of the orienting device, and the orienting device is arranged on a magnet, the rotating device is fixed on the magnet; the rotating device is movably connected to the orienting device; and the rotating device is configured to drive the orienting device to rotate relative to the magnet, such that the radio frequency antenna on the orienting device can be drived to rotate, and echo signals in different directions can be acquired by the radio frequency antenna. The purpose of multi-directional measurement can be achieved, and the overall properties of an undisturbed stratum can be reflected by the applicant.

Downhole three-dimensional scanning magnetic resonance imaging logging instrument, and a probe, an antenna thereof

The present invention provides a nuclear magnetic resonance logging instrument probe with double-layered magnets and an antenna excitation method, the nuclear magnetic resonance logging instrument probe includes: a probe framework and a shielding layer arranged in the probe framework; a plurality of main magnets are provided above and below the shielding layer, respectively; central axes of the main magnets are parallel with each other, and distances between the central axes of each of the main magnets and a central axis of the probe framework are the same; a distance between central axes of any two main magnets is not smaller than a first preset value; and an antenna is provided at outer side of each main magnety. In the present invention, circumferential recognizing capability of the nuclear magnetic resonance logging instrument probe can be improved and three-dimensional (radial, axial and circumferential) stratum detection can be achieved.

Nuclear magnetic resonance logging instrument probe with double-layered magnets and antenna excitation method

The present invention provides a nuclear magnetic resonance logging instrument probe with multi-layered magnet and an antenna excitation method, the nuclear magnetic resonance logging instrument probe includes a probe skeleton, multiple magnet assemblies and a plurality of antennas; the probe skeleton is of a cylindrical shape, multiple magnet assemblies are distributed in the circumferential direction of the probe skeleton; the magnet assembly includes at least two layers of magnet arranged from top to bottom, the magnet is magnetized in a radial direction, two adjacent layers of magnet are magnetized in opposite directions; an antenna is arranged outside each magnet assembly, multiple antennas are independently fed. In the nuclear magnetic resonance logging instrument probe and antenna excitation method, through exciting different antennas, detection of stratum information at different azimuth angles is realized, which improves circumferential resolution of the probe, realize stratum detection in three dimensions along radius, axis and circumference.

Nuclear magnetic resonance logging instrument probe with multi-layered magnet and antenna excitation method

The present invention provides a three-dimensional nuclear magnetic resonance logging instrument probe, a logging instrument and an antenna excitation method, where the probe includes: a probe framework, a magnet and an antenna; four magnets are uniformly distributed along a circumference of the probe framework, the magnets are magnetized in a radial direction of the probe framework, two magnets placed opposite to each other are magnetized from outside to inside, and the other two magnets placed opposite to each other are magnetized from inside to outside; in the probe framework, each of the magnets is provided with independently fed antennas; antennas corresponding to each of the magnets comprise a left antenna provided on one side of the corresponding magnet and a right antenna provided on the other side of the corresponding magnet; the left antenna and the right antenna corresponding to each magnet are electrically connected.

Three-dimensional nuclear magnetic resonance logging instrument probe, logging instrument and antenna excitation method

The present invention provides a multi-azimuth nuclear magnetic resonance logging instrument and an antenna excitation method, the nuclear magnetic resonance logging instrument includes: a probe framework and a shielding layer arranged in the probe framework; a plurality of main magnets are provided above and below the shielding layer, respectively; central axes of the main magnets are parallel with each other, and distances between the central axes of each of the main magnets and a central axis of the probe framework are the same; a distance between central axes of any two main magnets is not smaller than a first preset value; and an antenna is provided at outer side of each main magnet, and a plurality of the antennas are fed independently. In the present invention, circumferential recognizing capability of the nuclear magnetic resonance logging instrument can be improved and three-dimensional (radial, axial and circumferential) stratum detection can be achieved.

Multi-azimuth nuclear magnetic resonance logging instrument and antenna excitation method

The present invention provides a multi-detecting depth nuclear magnetic resonance logging tool and probe, and an antenna excitation method, the probe of nuclear magnetic resonance logging tool includes: a housing, a magnet and an antenna array apparatus; the magnet is fixedly arranged in the housing; the antenna array apparatus includes at least two groups of antenna arrays distributed along circumference of the magnet, and each group of antenna arrays include N layers of independently fed antennas; k-th layer antenna is arranged between the magnet and (k+1)-th layer antenna, k=1, 2, . . . N&#x2212;1; the antenna is fixed on a support, and the support is fixedly connected to the housing. In the present invention, stratum information detection at different azimuth angles is achieved by exciting different antenna arrays, so that circumferential recognizing capability of nuclear magnetic resonance logging tool probe is improved and three-dimensional (radial, axial and circumferential) stratum detection is achieved.

Growing community of inventors

Beijing, China

Sihui Luo