High-resolution logging-while-drilling device adopting gamma and side-scanning comprehensive imaging

Abstract

The invention discloses a high-resolution logging-while-drilling device adopting gamma and side-scanning comprehensive imaging. The high-resolution logging-while-drilling device adopting gamma and side-scanning comprehensive imaging comprises an outer drill collar, wherein an upper-part wear-resistant ring is arranged at one end of the outer drill collar, and a lower-part anti-wear belt is arranged at the other end of the outer drill collar; an inner mandrel is arranged in the outer drill collar; a gamma detector, a pseudosymmetric emission electrode T3, a measurement electrode T2, a measurement electrode T1, a quadrant reception pole plate, a button reception electrode and a measurement electrode T4 are sequentially arranged on the inner mandrel between the upper-part wear-resistant ringand the lower-part anti-wear belt; the gamma detector and the button reception electrode are used for gamma imaging and resistivity imaging; the quadrant reception pole plate is used for realizing anazimuthal side resistivity measurement function; and the pseudosymmetric emission electrode T3, the measurement electrode T2, the measurement electrode T1 and the measurement electrode T4 are used forrealizing different depth-sounding resistivity measurements. The high-resolution logging-while-drilling device adopting gamma and side-scanning comprehensive imaging is reasonable in structural layout, high in reliability, simple to machine, and convenient to maintain and extend.

Description

technical field [0001] The invention belongs to the technical field of logging-while-drilling devices, in particular to a logging-while-drilling device with high-resolution gamma and lateral scanning integrated imaging. Background technique [0002] Among petroleum LWD tools, imaging-while-drilling tool is a relatively advanced tool. This kind of instrument can not only effectively identify the reservoir boundary, feed back the drilling construction status, adjust the wellbore trajectory in time, control the drilling tool to travel through the best position in the oil layer, and is suitable for geosteering of thin-bed horizontal wells and improve the drilling rate of oil layers; at the same time It is also possible to scan the borehole to realize full borehole scanning imaging for formation evaluation. [0003] At present, most of the lateral-type resistivity logging tools while drilling adopt symmetrical electrode structure, the length of the instrument is relatively long,...

AI Technical Summary

Problems solved by technology

[0005] The technical problem to be solved by the present invention is to provide a high-resolution gamma and lateral scanning comprehensive imaging logging-while-drilling device for the above-mentioned deficiencies in the prior art. The length of LWD instruments is too long. The transmission system solves the problem of easy wear and drop of traditional measuring electrodes by adopting the structure of transmitting coils; by designing the four-quadrant surrounding receiving electrode structure, it solves the problem that lateral instruments cannot carry out azimuth. The problem of lateral resistivity measurement; through the small-diameter high-resolution button electrode and the fixed installation structure design of the gamma probe, the integrated design of gamma imaging and high-resolution lateral resistivity imaging on the instrument is realized; through the overall mechanical structure design, the realization 175°C, 140MPa technical indicators, to solve the needs of domestic deep wells and ultra-deep wells that cannot be operated

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