A variable diameter stabilizer

Abstract

The invention relates to a variable gauge stabilizer. The variable gauge stabilizer comprises a shell, wherein a central tube is arranged in the shell; a conical sleeve is sleeved on the outer diameter of a central tube; a baffle ring which is arranged on the central tube and is used for pushing the conical sleeve upwards when the central tube moves upwards is arranged below the conical sleeve; a stabilizing block is arranged on the shell; reset springs are arranged at the two ends of the stabilizing block; the stabilizing block is contacted with the conical sleeve; lugs are uniformly distributed on the outer diameter of the central tube along the radial direction; piston holes are uniformly distributed in the central tube along the radial direction; pistons are arranged in the piston holes; a screw cap for adjusting the axial displacement of the central tube and carrying the weight of a lower drill column is arranged at the bottom end of the central tube. By adopting the variable gauge stabilizer, the aim of varying the outer diameter of the stabilizer through ground operation is fulfilled. The stabilizer can be kept in different working states by changing the sequences of pump starting and bit weight increasing rotation, thereby fulfilling the aim of using stabilizers of different outer diameters in different well sections. Meanwhile, in trip-out operation, the stabilizer is kept in a contraction state. The variable gauge stabilizer is simple in structure, and the well drilling efficiency is increased.

Description

technical field [0001] The invention relates to a variable-diameter stabilizer. Background technique [0002] In the drilling construction of directional wells, horizontal wells and extended-reach wells, in order to control and adjust the wellbore inclination, it is usually stabilized by using drill pipes of different sizes and lengths, weighted drill pipes, drill collars, etc. Drill tool assembly for deflection building, deflection stabilization or deflection declination. Using the traditional fixed stabilizer, because of its fixed structure, the replacement of the stabilizer must be realized by tripping, which increases the auxiliary time of drilling operations. There are technical problems such as reaming in case of resistance, anti-deviation in easily deviated formations, control of directional wellbore trajectory, and increased mechanical speed, which may easily cause the phenomenon of scraping the well wall and "pulling the piston", which increases the soaking time of...

AI Technical Summary

Problems solved by technology

Using the traditional fixed stabilizer, because of its fixed structure, the replacement of the stabilizer must be realized by tripping, which increases the auxiliary time of drilling operations, and the fixed stabilizer is used in tripping, directional and other working conditions. There are technical problems such as reaming when encountering resistance, anti-deviation in easily deviated formations, control of directional wellbore trajectory, and increasing mechanical speed, which may easily cause the phenomenon of scraping the well wall and "pulling the piston", which increases the soaking time of the mud on the well wall. In this way, the drilling construction period is prolonged, the drilling time is reduced, and even the well wall becomes unstable, resulting in complex downhole accidents such as well collapse and blowout.

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