scholarly journals Design of a New Acoustic Logging While Drilling Tool

Sensors ◽  
2021 ◽  
Vol 21 (13) ◽  
pp. 4385
Author(s):  
Kai Zhang ◽  
Baohai Tan ◽  
Wenxiu Zhang ◽  
Yuntao Sun ◽  
Jian Zheng ◽  
...  

To obtain qualified logging while drilling (LWD) data, a new acoustic LWD tool was designed. Its overall design is introduced here, including the physical construction, electronic structure, and operation flowchart. Thereafter, core technologies adopted in this tool are presented, such as dominant exciting wave bands of dipole source, a sine wave pulse excitation circuit, broadband impedance matching, and an intellectualized active reception transducer. Lastly, we tested this tool in the azimuthal anisotropy module well, calibration well, and normal well, working in the model of the cable, sliding eye, and logging while drilling. Experiments showed that the core technologies achieved ideal results and that the LWD tool obtained qualified data.

Geophysics ◽  
2018 ◽  
Vol 83 (5) ◽  
pp. D165-D171
Author(s):  
Zhong Wang ◽  
Huaping Wang ◽  
Treston Davis ◽  
Jing Li ◽  
Suming Wu ◽  
...  

Geosteering is a key technique to increase oil- and gas-production rates, especially within a thin reservoir layer. The purpose of geosteering in the production zone is to keep the drilling path in oil- and gas-bearing reservoirs. To keep the drilling system inside the production zone, downhole sensors must be able to detect bed boundaries, which include identifying the boundary location with respect to the sensor and the boundary distance from the sensor. We have developed a directional resistivity logging-while-drilling (LWD) tool for geosteering applications. The directional LWD tool is equipped with a joint-coil antenna composed of an axially polarized coil Rz connected in series with two transversely polarized coils Rx. During a revolution around the axis of the tool, the voltage of the axial coil VRz, voltage of the transverse coils VRx, and tool face angle [Formula: see text], which indicates the boundary direction, can be extracted through curve fitting the total voltage response of the joint-coil antenna. The distance to the boundary can be derived from a 1D inversion. The LWD tool has been tested in several reservoirs in China, and it has a demonstrated capability to provide reliable and accurate estimations of the boundary direction and distance. Field data indicate that the boundary detection depth can reach 2.1 and 1.7 m when the tool is in a sand and shale formation. Using wireline-logging data from surrounding wells as reference, deviations between the reference and the measured distance to the boundary are within 0.2 m.


Sensors ◽  
2019 ◽  
Vol 19 (12) ◽  
pp. 2754 ◽  
Author(s):  
Gaoyang Zhu ◽  
Muzhi Gao ◽  
Fanmin Kong ◽  
Kang Li

Logging while drilling (LWD) plays a crucial role in geo-steering, which can determine the formation boundary and resistivity in real time. In this study, an efficient inversion, which can accurately invert formation information in real time on the basis of fast-forward modeling, is presented. In forward modeling, the Gauss–Legendre quadrature combined with the continued fraction method is used to calculate the response of the LWD instrument in a layered formation. In inversion modeling, the Levenberg–Marquardt (LM) algorithm, combined with the line search method of the Armijo criterion, are used to minimize the cost function, and a constraint algorithm is added to ensure the stability of the inversion. A positive and negative sign is added to the distance parameter to determine whether the LWD instrument is located above or below the formation boundary. We have carried out a series of experiments to verify the accuracy of the inversion. The experimental results suggest that the forward algorithm can make the infinite integral of the Bessel function rapidly converge, and accurately obtain the response of the LWD instrument in a layered formation. The inversion can accurately determine the formation resistivity and boundary in real time. This is significant for geological exploration.


2002 ◽  
Author(s):  
Jan Morley ◽  
Ralf Heidler ◽  
Jack Horkowitz ◽  
Bruno Luong ◽  
Charles Woodburn ◽  
...  

2018 ◽  
Vol 151 ◽  
pp. 309-317 ◽  
Author(s):  
Zhengming Kang ◽  
Shizhen Ke ◽  
Ming Jiang ◽  
Chengfang Yin ◽  
Anzong Li ◽  
...  

2009 ◽  
Author(s):  
Taher M.N. El-Gezeery ◽  
Fawaz Al-Saqran ◽  
Ekpo Ita Archibong ◽  
Oluwafemi Oyeyemi ◽  
Vivekanand Chimirala

1996 ◽  
Author(s):  
John W. Minear ◽  
Dale R. Heysse ◽  
Paul M. Boonen

2019 ◽  
Vol 2 (3) ◽  
pp. 89-94
Author(s):  
Kirill Danilovskiy ◽  
Vyacheslav Glinskikh ◽  
Oleg Nechaev

Reservoir microimaging tools are currently one of the most high-tech devices used in wireline logging and logging-while-drilling. Based on a three-dimensional numerical simulation, the spatial resolution of the first Russian lateral scanning logging-while drilling tool was estimated. An algorithm for constructing a geoelectric model with an arbitrary distribution of electrical resistivity in the near-wellbore space is described.


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