Omnibearing magnetostatic-field while-drilling positioning method and positioning system for relief well

Abstract

The invention relates to an omnibearing magnetostatic-field while-drilling positioning method and positioning system for a relief well. The method comprises: (1), a three-axis high-precision flux gate sensor, a three-axis acceleration sensor and a three-axis gyro are installed at a front end of an underground measurement exploring tube; (2), before going down a well, an operator measures a geomagnetic field vector affected by a drill head; (3), after an inclination stage task of a relief well is started, according to magnetic field measurement data obtained by the high-precision flux gate sensor, a measurement while drilling (MWD) exploring tube carries out space projection operation on each group of obtained magnetic field measurement values of a rescued well casing tube by combining attitude information of the MWD, thereby obtaining magnetic field component strength data of the magnetic field of the rescued well casing tube on a horizontal plane in a drilling direction and a direction perpendicular to the drilling direction; (4), least square operation is carried out on the obtained magnetic field component strength data of the rescued well casing tube after space projection of multiple times, thereby obtaining a spatial position of the drilling exploring tube relative to the rescued well casing tube; and (5), filter operation is carried out by a Kalman filter, so that a precise spatial position of a relief well exploring tube relative to the rescued well is obtained.

Description

technical field [0001] The invention relates to an omnidirectional static magnetic field rescue well positioning method and a positioning system while drilling, and relates to the technical field of static magnetic field rescue well positioning. Background technique [0002] Directional drilling refers to the drilling process that makes the wellbore reach the target layer along the pre-designed direction and trajectory. It can be widely used in deviated drilling, horizontal drilling and butt drilling. Rescue wells refer to wells that are drilled to communicate with the rescued well and control the blowout when the rescued well has a severe blowout or blowout out of control. It is an effective method to solve blowouts, oil spills and other accidents. Whether the accident can end is the last line of defense for blowout accidents. Accurate detection of the relative distance and orientation between the rescue well and the accident well with the help of the necessary electromagn...

AI Technical Summary

Problems solved by technology

[0006] In view of the above problems, the object of the present invention is to provide an omnidirectional static magnetic field rescue well positioning method while drilling and a positioning system, which can effectively fill the gap in the three-dimensional space positioning method in the static magnetic field rescue well tilting stage, and solve the traditional MWD measurement while drilling device. Poor continuity and accuracy, poor real-time performance, and severe noise interference during static magnetic field positioning

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