Shell-guided deflection drilling tools

Abstract

The invention discloses a shell guiding type deflecting drilling tool comprising a guiding shell. The guiding shell is provided with a plurality of annular grooves which are distributed at intervals in the length direction of the guiding shell. The multiple annular grooves divide the guiding shell into a plurality of shell short sections. Each annular groove communicates with a T-shaped groove, and all the T-shaped grooves are distributed in one side of the guiding shell in the length direction of the guiding shell and penetrate through the guiding shell. In every two adjacent shell short sections, one shell short section is provided with the corresponding T-shaped groove, and the other shell short section is provided with a T-shaped connecting plate located in the T-shaped groove. The T-shaped connecting plates can move by a preset distance along the T-shaped grooves. The shell guiding type deflecting drilling tool further comprises a flexible drilling rod arranged in the guiding shell and comprising a first drilling rod connector, a second drilling rod connector, a deflecting drill bit and a plurality of drilling rod short sections which are connected head to tail and located between the first drilling rod connector and the second drilling rod connector. Every two adjacent drilling rod short sections are connected through a universal joint.

Description

technical field [0001] The invention relates to the field of oil exploitation, in particular to a casing-guided deflection drilling tool. Background technique [0002] In the petroleum industry, the ultra-short-radius sidetracking technology, in which multiple layers are simultaneously exploited in the same well, is one of the main means of increasing oil production in modern times. [0003] According to the different radius of curvature radial horizontal wells are divided into long-radius wells, medium-radius wells, short-radius wells and ultra-short-radius wells. Wells with a radius of curvature greater than 500 meters are long-radius wells, those with a radius of curvature of 100 to 500 meters are medium-radius wells, those with a radius of curvature of 20 to 100 meters are short-radius wells, and those with a radius of curvature less than 20 meters are ultra-short-radius wells. A well with a shorter radius of curvature is more difficult to drill and requires higher dril...

AI Technical Summary

Problems solved by technology

[0014] In addition, the existing flexible drill pipes with universal joints generally adopt the transmission pin and ball transmission mode, and the structure is complex. The flexible drill pipe with this structure will have obvious stress concentration, which is prone to fatigue wear and has low reliability.

At the same time, a single flexible unit contains too many parts, each flexible unit needs to be welded, the assembly process is complicated, and the interchangeability is poor

[0015] In addition, the existing conventional flexible drill pipes all adopt a universal joint transmission structure, which has a large degree of curvature, and can sidetrack horizontal wells through ultra-short radius

However, because there is no corresponding external guide device, it is difficult to control the drilling azimuth and direction during the drilling process

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