CN-117365325-B - Reducing stabilizer

CN117365325BCN 117365325 BCN117365325 BCN 117365325BCN-117365325-B

Abstract

The invention provides a reducing stabilizer which comprises a shell, a centralizing block movably arranged on the outer wall of the shell, a mandrel axially and slidably arranged in the shell, and a spring sleeved in the shell, wherein two ends of the spring are respectively abutted against the mandrel and the shell, a bulge is arranged on the outer wall of the mandrel, corresponding to the centralizing block, and the bulge is configured to push the centralizing block radially after the mandrel moves in the direction of the shell, so that the outer diameter of the stabilizer is enlarged. According to the invention, the protrusion is driven to move by the core shaft capable of radially moving, so that the centering block is pushed to radially move, and the outer diameter of the stabilizer is changed, thereby achieving the purpose of reducing. In addition, the guide inclined plane is arranged on the centralizing block, and the protrusion is matched with the guide inclined plane, so that stepless diameter change of the stabilizer can be realized. The invention has the characteristics of variable outer diameter and controlled outer diameter of bit pressure, can adapt to different borehole sizes, has stable and reliable diameter variation, and can effectively improve the drilling efficiency.

Inventors

HU YANFENG
TAO XINGHUA
WANG JIACHANG
SUO ZHONGWEI
XUAN LINGCHAO

Assignees

中国石油化工股份有限公司
中石化石油工程技术研究院有限公司

Dates

Publication Date: 20260512
Application Date: 20220701

Claims (4)

1. A variable-diameter stabilizer, which comprises a main body, characterized by comprising the following steps: A housing (7); the centering blocks (5) are movably arranged on the outer wall of the shell (7), and the centering blocks (5) are uniformly distributed along the circumferential direction of the shell (7); A mandrel (2) axially slidably arranged in the housing (7); The spring (4) is sleeved in the shell (7), and two ends of the spring (4) are respectively abutted against the mandrel (2) and the shell (7); Wherein, a bulge (204) is arranged on the outer wall of the mandrel (2) corresponding to each centralizing block (5), and the bulge (204) is configured to push the centralizing blocks (5) radially after the mandrel (2) moves towards the shell (7), so as to enlarge the outer diameter of the stabilizer; The centralizing block (5) is rotationally connected with the shell (7), the rotation axis of the centralizing block (5) is parallel to the central axis of the shell (7), a rotating shaft (501) is arranged at the edge of the centralizing block (5), the centralizing block (5) is rotationally connected with the shell (7) through the rotating shaft (501), The shell (7) comprises a shell (6) and an upper gland (3) arranged at the top end of the shell (6), the righting block (5) is positioned between the upper gland (3) and the shell (6), the upper gland (3) and the shell (6) are respectively provided with a mounting hole (602) for mounting the rotating shaft (501), The mandrel (2) comprises a first mandrel (201) and a second mandrel (202), the outer diameter of the second mandrel (202) is larger than that of the first mandrel (201), a limiting surface (304) for abutting against the end face of the second mandrel (202) is arranged on the inner wall of the upper gland (3), the outer wall of the second mandrel (202) is a regular hexagon, the inner wall of the shell (7) is an inner hexagon corresponding to the second mandrel (202), A central shaft (604) is arranged inside the shell (6) along the central axis of the shell, the central shaft (604) is sleeved with the mandrel (2), an annulus exists between the second mandrel (202) and the central shaft (604), and the spring (4) is positioned in the annulus.
2. The reducing stabilizer according to claim 1, characterized in that a guide slope (502) is provided at a position of the righting block (5) in contact with the projection (204).
3. The reducing stabilizer according to claim 2, characterized in that the number of the righting blocks (5) is three, and three mounting grooves (607) for arranging the righting blocks (5) are uniformly provided along the circumferential direction of the housing (7).
4. A variable diameter stabilizer according to any one of claims 1-3, characterized in that an upper joint (1) is provided at the top of the mandrel (2), a lower joint (601) is provided at the bottom of the housing (7), and a spiral flow passage is provided at the outer wall of the housing (7).

Description

Reducing stabilizer Technical Field The invention belongs to the technical field of oil and gas drilling, and particularly relates to a reducing stabilizer. Background In the oil and gas well drilling process, due to the difference of the size of a drill bit and the size of a drilling tool and the size of a borehole, when the dip angle of a drilled stratum is large, the lithology of the stratum is changed greatly, the drill feeding is uneven or the borehole expansion rate is large, the problems of exceeding the standard of the well deviation of a vertical well, large difficulty in controlling the track of an inclined well and a horizontal well and the like often occur. To avoid this, the drilling assembly is usually optimized, and it is most straightforward to add centralizers to the drilling assembly to increase the rigidity and stability of the drilling tool, but existing bit stabilizers are basically either fixed outer diameter sizes or hydraulic variable outer diameter based centralizers. Both of these stabilizers have significant drawbacks: The fixed outer diameter centralizer is influenced by the change of the expansion rate of the well bore, the centralizing effect is unstable, and in a soft stratum, the situation that the clearance between the outer diameter of the centralizer and the well bore is too large easily occurs, so that the axis of the drill bit deviates from the axis of the drill string, and the drilling effect is influenced; the hydraulic reducing centralizer is characterized in that the outer diameter of the centralizer is changed stepwise by adopting the displacement change of a ground slurry pump, and the outer diameter of the centralizer is 2-3 stages generally. In the drilling process, the factors influencing the displacement change are many, and the diameter changing condition of the hydraulic diameter changing centralizer is difficult to accurately control on the ground. And the hydraulic reducing centralizer has a complex structure, and is not beneficial to the subsequent equipment maintenance. Disclosure of Invention Aiming at the technical problems, the invention aims to provide a reducing stabilizer which can stably centralize a drilling tool in the drilling process. The invention provides a reducing stabilizer, which comprises a shell, a centralizing block movably arranged on the outer wall of the shell, a mandrel axially and slidably arranged in the shell, and a spring sleeved in the shell, wherein two ends of the spring are respectively abutted against the mandrel and the shell, a protrusion is arranged on the outer wall of the mandrel, corresponding to the centralizing block, and the protrusion is configured to be capable of radially pushing the centralizing block after the mandrel moves in the direction of the shell, so that the outer diameter of the stabilizer is enlarged. In one embodiment, a guide slope is provided at a position of the righting block in contact with the projection. In one embodiment, the number of the centralizing blocks is three, and three mounting grooves for arranging the centralizing blocks are uniformly formed along the circumferential direction of the shell. In one embodiment, the righting block is rotatably coupled to the housing, and the axis of rotation of the righting block is parallel to the central axis of the housing. In one embodiment, a rotating shaft is arranged at the edge of the centralizing block, and the centralizing block is rotatably connected to the shell through the rotating shaft. In one embodiment, the shell comprises a shell and an upper gland arranged at the top end of the shell, the righting block is positioned between the upper gland and the shell, and mounting holes for mounting the rotating shaft are formed in the upper gland and the shell. In one embodiment, the mandrel comprises a first mandrel and a second mandrel, the outer diameter of the second mandrel is larger than that of the first mandrel, and a limiting surface for abutting against the end face of the second mandrel is arranged on the inner wall of the upper gland. In one embodiment, the outer wall of the second mandrel is regular hexagonal, and the inner wall of the housing is provided as an inner hexagon corresponding to the second mandrel. In one embodiment, a central shaft is arranged inside the shell along the central axis of the shell, the central shaft is sleeved with the central shaft, an annulus exists between the second central shaft and the central shaft, and the spring is positioned in the annulus. In one embodiment, the upper joint is arranged at the top of the mandrel, the lower joint is arranged at the bottom of the shell, and the spiral flow passage is arranged on the outer wall of the shell. Compared with the prior art, the application has the advantages that: Aiming at the problem that the centralizing effect of the existing fixed-size drill bit stabilizer and the hydraulic variable-diameter stabilizer is unstable, the invention provides the