Method for preventing self rotation of continuous gyro inclinometer in oil well

Abstract

The invention discloses a method for preventing self rotation of a continuous gyro inclinometer in an oil well. According to the method disclosed by the invention, a rotating short section is additionally arranged between an upper centralizer and a headstall short section which is connected with an armor cable; one end of the rotating short section is connected with the headstall short section; the other end of the rotating short section is connected with the continuous gyro inclinometer; the inside of the rotating short section is composed of one group of coaxial sliding rings; by rotary sliding between the sliding rings, the upper centralizer is not affected by torque release of cable stress and is kept in a low-speed rotation state or a non-rotation state; and thus the continuous gyro inclinometer which is connected with the upper centralizer is prevented from rotating automatically in the oil well or the self-rotation speed of the continuous gyro inclinometer is reduced. The methoddisclosed by the invention realizes that the stress of the cable is released with the rotating short section, while the continuous gyro inclinometer below the upper centralizer and a lower centralizer do not rotate with the rotating short section due to relatively large friction force, thereby eliminating the influences, on testing precision of the instrument, of self rotation and solving the problem that the small-gradient position precision error of the instrument is large no matter point measurement is adopted or continuous measurement is adopted.

Description

technical field [0001] The invention relates to a method for preventing a continuous gyro inclinometer from rotating in an oil well, and belongs to the technical field of downhole instruments in oil fields. Background technique [0002] As domestic easy-to-exploit oil enters the middle and later stages, the development and utilization of small block oil layers and thin oil layers is an effective means to tap potential and increase efficiency, and the development of extended reach wells, highly deviated wells, cluster wells, and horizontal wells is an effective technological solution Therefore, the domestic drilling industry needs a gyro continuous inclinometer with higher precision and more intensive test data for borehole trajectory testing. The gyro continuous inclinometer has the advantages of high precision, continuous testing of borehole trajectory, and high testing efficiency. In the process of oil well logging, the gyro continuous inclinometer is lowered into the wel...

AI Technical Summary

Problems solved by technology

However, the high-speed random rotation of the gyro continuous inclinometer itself and the interference information caused by random vibration make the test accuracy of the gyro continuous inclinometer drop sharply in small-inclination wells (inclination angles less than 3°) or horizontal wells (inclination angles greater than 85°)

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