Method for reducing exterior angle deviation measuring errors of directional drilling assembly and drilling tool

Abstract

The invention discloses a method for reducing exterior angle deviation measuring errors of a directional drilling assembly. The method comprises the steps that S1) a directional groove (5) is formed in one end, connected with a bent screw (3), of a non-magnetic drill collar (2), and an MWD pup joint (1) is fixedly connected with the non-magnetic drill collar (2); S2) the included angle theta 1 between a directional key (4) of the MWD pup joint (1) and the directional groove (5) is measured; S3) the non-magnetic drill collar (2) is fixedly connected with the bent screw (3) and the included angle theta 2 between the directional groove (5) and the high side of the bent screw (3) is measured; S4) the exterior angle deviation theta between the high side of the bent screw (3) and directional key (4) is theta=theta 1 + / - theta 2. The invention further discloses a drilling tool used for measuring the exterior angle deviation with the method. The method for reducing the exterior angle deviation measuring errors of the directional drilling assembly and the drilling tool have the advantages that theta 1 can be measured on the ground conveniently and accurately, the exterior angle deviation measuring errors of the directional drilling assembly are effectively reduced, construction accuracy in a directional well construction process is improved, and a more ideal well track is acquired.

Description

technical field [0001] The invention relates to the technical field of directional drilling tool angle measurement, in particular to a method and a drilling tool for reducing the measurement error of the outer angle difference of a directional drilling tool assembly. Background technique [0002] During the drilling process, in order to drill with high precision according to the predetermined azimuth and well deviation, it is necessary to accurately measure the tool face angle difference of the directional tool. The directional drilling assembly usually adopts a bent screw, which has a bent point, that is, a high side, and there is an angle difference (external angle difference) between it and the directional key of the MWD (Measurement While Drilling) sub-section, and the difference between the directional key and the tool face of the probe There is also a certain angle difference (internal angle difference), and the angle difference between the high side and the probe tool...

AI Technical Summary

Problems solved by technology

After the measurement tools used in the prior art are projected on the plane, due to various operational reasons, it is difficult to identify whether the projection is parallel to the axis of the non-magnetic drill collar, and the length of the non-magnetic drill collar is about 10 meters, with a small error It is possible to reach a large value after amplification, so the measurement error is large, resulting in the failure to obtain the ideal wellbore trajectory, or even deviate from the intended target

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