Rigid casing stabilizer

By introducing a balanced cutting mechanism into the rigid casing stabilizer, the problem of casing obstruction under irregular well diameters was solved, enabling smooth casing installation and protection, and avoiding casing bending and damage.

CN121363387AActive Publication Date: 2026-01-20DAQING TIANDEZHONG PETROLEUM SCI & TECH CO LTD

Patent Information

Application Number
CN202511937112.4
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2025-12-22
Publication Date
2026-01-20
Estimated Expiration
2045-12-22

AI Technical Summary

Technical Problem

Existing rigid casing stabilizers encounter significant resistance during casing installation when the well diameter is irregular, which can easily cause casing bending and damage, making it difficult to meet construction requirements.

Method used

A rigid casing stabilizer with a balanced cutting mechanism was designed, including a central casing and a centralizing sleeve. The lower part of the centralizing sleeve is equipped with a lifting sleeve and a cutting mechanism. The main cutting block and the auxiliary cutting block cut at irregular parts of the well wall. Through helical motion and the action of springs, the casing is smoothly lowered and protected.

Benefits of technology

This effectively reduces frictional resistance during the casing installation process, protects the casing from damage, and ensures smooth construction.

✦ Generated by Eureka AI based on patent content.

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    Figure CN121363387A_ABST
Patent Text Reader

Abstract

The invention discloses a rigid casing stabilizer and relates to the technical field of oil field low-carbon exploitation. An annular counter bore is upwards formed in the lower end face of the centralizing sleeve, a lifting sleeve is arranged in the annular counter bore and connected with the annular counter bore through threads, the upper portion of the lifting sleeve is connected with a compression spring A through a plane bearing, the upper portion of the compression spring A abuts against the bottom of the annular counter bore, and a balance cutting mechanism is arranged on the lower portion of the lifting sleeve. The drilling tool has the beneficial effects that the balance cutting mechanism is arranged on the lower portion of the centralizing sleeve, when the well diameter is irregular during casing running and the main cutting block and the auxiliary cutting block encounter the inner protrusion of the well wall, the lifting sleeve starts to rotate and ascend, the main cutting block and the auxiliary cutting block cut the well wall, the casing can be smoothly put into a shaft, and the drilling tool is convenient to use. And during cutting, large bending force cannot be formed on the casing pipe, so that the casing pipe is protected.
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Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of low-carbon oilfield exploitation, and in particular to an energy-saving and environment-friendly rigid casing stabilizer. BACKGROUND

[0002] The rigid casing stabilizer is generally a righting strip with a strip-shaped structure, is widely used in casing operation in a straight well or a high-deviation well, has the characteristics of small starting force and large resetting force, and can effectively reduce the frictional resistance during casing lowering. SUMMARY

[0003] In order to solve the problem that the existing rigid casing stabilizer is not suitable for irregular well diameters, the present application provides a rigid casing stabilizer.

[0004] The technical scheme provided by the present application is as follows: a rigid casing stabilizer comprises a body, the body is divided into a central pipe and a righting sleeve, the righting sleeve is provided with uniformly distributed flow guide grooves on the outer circle, and the pipe wall of the central pipe is provided with rivet holes; The lower end surface of the righting sleeve is upwardly provided with an annular counterbore, the annular counterbore is provided with a lifting sleeve, the lifting sleeve is connected with the annular counterbore through threads, the upper part of the lifting sleeve is connected with a compression spring A through a plane bearing, the upper part of the compression spring A is located on the bottom of the annular counterbore, and the lower part of the lifting sleeve is provided with a balance cutting mechanism; The balance cutting mechanism comprises three main cutting sleeves and three auxiliary cutting blocks, the main cutting sleeve comprises a main cutting block and a driving ring, the driving ring is provided with an inwardly extending outer inclined surface at the center symmetric part of the main cutting block, the outer side of the outer inclined surface is provided with an auxiliary cutting block, the inner side of the auxiliary cutting block is provided with an inner inclined surface, the angle of the inner inclined surface is the same as that of the outer inclined surface, the driving ring is a non-closed ring structure, and a gap exists in the clockwise part of the auxiliary cutting block of the driving ring; Three arc-shaped long holes penetrating the upper and lower parts are formed in the driving ring, the three arc-shaped long holes are circumferentially distributed, and a radial long hole penetrating the upper and lower parts is formed in the auxiliary cutting block. The main cutting sleeve and the auxiliary cutting block are arranged in three layers, one main cutting sleeve and one auxiliary cutting block form a layer, the inner inclined surface of the auxiliary cutting block is attached to the outer inclined surface of the main cutting sleeve, the main cutting sleeve and the auxiliary cutting block are circumferentially distributed, one positioning shaft A is arranged in the arc-shaped long hole of the three main cutting sleeves, the positioning shaft A is fixedly connected with the lifting sleeve, the positioning shaft A is attached to the side of the arc-shaped long hole in the clockwise direction, a compression spring C is arranged between the positioning shaft A and the other side of the arc-shaped long hole, positioning shaft B, positioning shaft C and positioning shaft D are arranged in the radial long holes of the three auxiliary cutting blocks, the positioning shaft B, the positioning shaft C and the positioning shaft D are fixedly connected with the lifting sleeve, the positioning shaft B, the positioning shaft C and the positioning shaft D are attached to the outer side of the radial long hole, and the compression spring B is arranged between the positioning shaft B, the positioning shaft C, the positioning shaft D and the inner side of the radial long hole.

[0005] The limiting sleeve is arranged below the lowermost main cutting sleeve and the lower auxiliary cutting block of the center tube.

[0006] The outer diameter of the main cutting sleeve and the auxiliary cutting block is the same as the outer diameter of the centralizing sleeve.

[0007] The graphite sleeve is arranged between the lifting sleeve and the center tube, the lower end of the graphite sleeve is limited by the stepped hole of the lifting sleeve, the upper end of the graphite sleeve is provided with a pressing ring, the pressing ring is limited on the upper part of the graphite sleeve, and the pressing ring is connected to the upper part of the lifting sleeve through bolts.

[0008] The connecting thread between the lifting sleeve and the annular counterbore is a non-self-locking thread.

[0009] The main cutting block is provided with a front inclined surface and a rear inclined surface in the counterclockwise direction, the front inclined surface and the rear inclined surface form a cutting edge therebetween, and the cutting structure of the auxiliary cutting block is the same as that of the main cutting block.

[0010] The present application has the following beneficial effects: the balance cutting mechanism is arranged at the lower part of the centralizing sleeve, when the lower sleeve encounters irregular well diameter, the main cutting block and the auxiliary cutting block encounter the inner convexity of the well wall, the lifting sleeve is pressed to rotate upward under the action of the thread, the main cutting block and the auxiliary cutting block cut the well wall, so that the sleeve can be smoothly lowered into the wellbore, the inner convexity cannot be completely cut in one upward movement, the sleeve can be lifted, the lifting sleeve is spirally lowered under the action of the compression spring A, and the sleeve is lowered again for cutting until it is smoothly passed through; When the well wall on one side is blocked, the main cutting sleeve rotates by an angle in the clockwise direction in the cutting process, the driving ring rotates, the outer inclined surface drives the auxiliary cutting block to move outward, is attached to the other side of the well wall, and the stress of the main cutting block during cutting is transmitted to the other side of the well wall through the auxiliary cutting block, so that a large bending force is not formed on the sleeve during cutting, thereby protecting the sleeve. BRIEF DESCRIPTION OF DRAWINGS

[0011] The present application has the following beneficial effects: the balance cutting mechanism is arranged at the lower part of the centralizing sleeve, when the lower sleeve encounters irregular well diameter, the main cutting block and the auxiliary cutting block encounter the inner convexity of the well wall, the lifting sleeve is pressed to rotate upward under the action of the thread, the main cutting block and the auxiliary cutting block cut the well wall, so that the sleeve can be smoothly lowered into the wellbore, the inner convexity cannot be completely cut in one upward movement, the sleeve can be lifted, the lifting sleeve is spirally lowered under the action of the compression spring A, and the sleeve is lowered again for cutting until it is smoothly passed through; Figure 1 is a structural schematic diagram of the present application. Figure Figure 2 Figure Figure 1 is the A-A cross-sectional view of Figure Figure Figure 3 is the B enlarged view of Figure Figure 1 Figure is the C enlarged view of Figure Figure 4 Figure Figure 1 is the working diagram of Figure Figure Figure 5 is the working diagram of Figure Figure 2 Figure Figure Figure 6 Figure Figure Figure 7 is the structure schematic diagram of the main cutting sleeve in the present application Figure Figure 8 is the structure schematic diagram of the auxiliary cutting block in the present application Figure Figure 9 is the appearance structure schematic diagram of the body in the present application

[0012] Figure 1 - body, 101 - centralizing sleeve, 102 - central tube, 103 - annular counterbore, 104 - flow guide groove, 2 - lifting sleeve, 3 - main cutting sleeve, 301 - main cutting block, 3011 - rear inclined surface, 3012 - front inclined surface, 3013 - cutting edge, 302 - driving ring, 303 - arc-shaped long hole, 304 - outer inclined surface, 4 - auxiliary cutting block, 401 - inner inclined surface, 402 - radial long hole, 5 - limiting sleeve, 6 - compression spring A, 7 - pin, 8 - rivet hole, 9 - positioning shaft A, 10 - positioning shaft B, 11 - positioning shaft C, 12 - positioning shaft D, 13 - compression spring B, 14 - compression spring C, 15 - plane bearing, 16 - graphite sleeve, 17 - compression ring DETAILED DESCRIPTION

[0013] As shown in Figure, a rigid casing stabilizer comprises a body 1, the body 1 is divided into two parts of a central tube 102 and a centralizing sleeve 101, the centralizing sleeve 101 is processed with uniformly distributed flow guide grooves 104, the pipe wall of the central tube 102 is provided with a rivet hole 8 for connecting the casing; Figures 1-9 The lower end surface of the centralizing sleeve 101 is upwardly provided with an annular counterbore 103, the annular counterbore 103 is provided with a lifting sleeve 2, the lifting sleeve 2 is connected with the annular counterbore 103 through threads, the upper part of the lifting sleeve 2 is connected with a compression spring A 6 through a plane bearing 15, the upper part of the compression spring A 6 is abutted on the bottom of the annular counterbore 103, and the lower part of the lifting sleeve 2 is provided with a balance cutting mechanism; The lower end surface of the centralizing sleeve 101 is upwardly provided with an annular counterbore 103, the annular counterbore 103 is provided with a lifting sleeve 2, the lifting sleeve 2 is connected with the annular counterbore 103 through threads, the upper part of the lifting sleeve 2 is connected with a compression spring A 6 through a plane bearing 15, the upper part of the compression spring A 6 is abutted on the bottom of the annular counterbore 103, and the lower part of the lifting sleeve 2 is provided with a balance cutting mechanism; The balanced cutting mechanism comprises three main cutting sleeves 3 and three auxiliary cutting blocks 4, the main cutting sleeve 3 comprises a main cutting block 301 and a driving ring 302, the driving ring 302 is provided with an inwardly extending outer inclined surface 304 at a central symmetrical position of the main cutting block 301, the outer inclined surface 304 is provided with the auxiliary cutting block 4 at the outer side, the auxiliary cutting block 4 is provided with an inner inclined surface 401 at the inner side, the inner inclined surface 401 is the same angle as the outer inclined surface 304, the driving ring 302 is a non-closed annular structure, and a gap exists in the clockwise position of the auxiliary cutting block 4; Three upper and lower through arc long holes 303 are formed in the driving ring 302, the three arc long holes 303 are circumferentially distributed, and an upper and lower through radial long hole 402 is formed in the auxiliary cutting block 4; The main cutting sleeve 3 and the auxiliary cutting block 4 are arranged in three layers, one main cutting sleeve 3 and one auxiliary cutting block 4 form one layer, the inner inclined surface 401 of the auxiliary cutting block 4 is attached to the outer inclined surface 304 of the main cutting sleeve 3, the main cutting sleeve 3 and the auxiliary cutting block 4 are circumferentially distributed, one positioning shaft A9 is arranged in the arc long hole 303 of the three main cutting sleeves 3, the positioning shaft A9 is fixedly connected with the lifting sleeve 2, the positioning shaft A9 is attached to the one side of the arc long hole 303 in the clockwise direction, a compression spring C14 is arranged between the positioning shaft A9 and the other side of the arc long hole 303, positioning shafts B10, C11 and D12 are arranged in the radial long holes 402 of the three auxiliary cutting blocks 4, the positioning shafts B10, C11 and D12 are fixedly connected with the lifting sleeve 2, the positioning shafts B10, C11 and D12 are attached to the outer side of the radial long hole 402, and the compression spring B13 is arranged between the positioning shafts B10, C11 and D12 and the inner side of the radial long hole 402.

[0014] The balanced cutting mechanism is arranged at the lower part of the centralizing sleeve 101, when the lower sleeve encounters irregular well diameters, the main cutting block 301 and the auxiliary cutting block 4 encounter the well wall, the lifting sleeve 2 is pressed, the lifting sleeve 2 is rotated and lifted under the action of the threads, the main cutting block 301 and the auxiliary cutting block 4 cut the well wall, so that the sleeve can be smoothly lowered into the wellbore, the sleeve can be lifted once, the lifting sleeve 2 is spirally lowered under the action of the compression spring A6, and the sleeve is lowered again for cutting until it is smoothly passed; When encountering an obstacle on one side of the well wall, as shown in the accompanying drawings Figure 5As shown, the main cutting sleeve 3 rotates an angle in the clockwise direction during cutting, and the outer inclined surface 304 drives the auxiliary cutting block 4 to move outward and stick to the other side of the well wall after the driving ring 302 rotates. The force of the main cutting block 301 is transmitted to the other side of the well wall through the auxiliary cutting block 4, so that no large bending force is formed on the casing during cutting, thereby protecting the casing. When the cutting is completed without resistance, the main cutting sleeve 3 returns to the original position under the action of the compression spring C14, and the auxiliary cutting block 4 returns to the original position under the action of the compression spring B13.

[0015] The center tube 102 is provided with a limiting sleeve 5 below the main cutting sleeve 3 and the auxiliary cutting block 4 at the lowermost side, and the limiting sleeve 5 and the center tube 102 are fixedly connected through a pin 7.

[0016] The outer diameter of the main cutting sleeve 3 and the auxiliary cutting block 4 is the same as the outer diameter of the centralizing sleeve 101.

[0017] The lifting sleeve 2 is provided with a graphite sleeve 16 between the center tube 102, the lower end of the graphite sleeve 16 is limited by the stepped hole of the lifting sleeve 2, the upper end of the graphite sleeve is provided with a compression ring 17, the compression ring 17 is limited on the upper part of the graphite sleeve 16, the compression ring 17 is connected to the upper part of the lifting sleeve 2 through bolts, and the graphite sleeve 16 plays a lubricating role between the lifting sleeve 2 and the center tube 102.

[0018] The connecting thread between the lifting sleeve 2 and the annular counterbore 103 is a non-self-locking thread, and the lifting sleeve 2 can be positively or negatively rotated to rise or fall.

[0019] The main cutting block 301 is provided with a front inclined surface 3012 and a rear inclined surface 3011 in the counterclockwise direction, and the cutting edge 3013 is formed between the front inclined surface 3012 and the rear inclined surface 3011, and the cutting structure of the auxiliary cutting block 4 is the same as that of the main cutting block 301.

Claims

1. A rigid cannula stabilizer comprising a body (1), characterized in that: The body (1) is divided into two parts of a central pipe (102) and a centralizing sleeve (101), the outer circle of the centralizing sleeve (101) is processed with uniformly distributed flow guide grooves (104), and the pipe wall of the central pipe (102) is opened with rivet holes (8); The lower end face of the centralizing sleeve (101) is opened with an annular counterbore (103) upward, the annular counterbore (103) is provided with a lifting sleeve (2), the lifting sleeve (2) is connected with the annular counterbore (103) through screw threads, the upper part of the lifting sleeve (2) is connected with a compression spring A (6) through a plane bearing (15), the upper part of the compression spring A (6) is abutted on the bottom of the annular counterbore (103), and the lower part of the lifting sleeve (2) is provided with a balance cutting mechanism; The balance cutting mechanism comprises three main cutting sleeves (3) and three auxiliary cutting blocks (4), the main cutting sleeve (3) comprises a main cutting block (301) and a driving ring (302), the driving ring (302) is processed with an inwardly extending outer inclined surface (304) at the central symmetrical part of the main cutting block (301), the outer side of the outer inclined surface (304) is provided with the auxiliary cutting block (4), the inner side of the auxiliary cutting block (4) is processed with an inner inclined surface (401), the angle of the inner inclined surface (401) is same as that of the outer inclined surface (304), the driving ring (302) is a non-closed annular structure, and a gap exists in the clockwise part of the driving ring (302) in the auxiliary cutting block (4); The driving ring (302) is opened with three upper and lower through arc long holes (303), the three arc long holes (303) are circumferentially uniformly distributed, and the auxiliary cutting block (4) is opened with an upper and lower through radial long hole (402); The main cutting sleeve (3) and the auxiliary cutting block (4) are arranged in three layers, one main cutting sleeve (3) and one auxiliary cutting block (4) form one layer, the inner inclined surface (401) of the auxiliary cutting block (4) is abutted on the outer inclined surface (304) of the main cutting sleeve (3), the main cutting sleeve (3) and the auxiliary cutting block (4) are circumferentially uniformly distributed, one positioning shaft A (9) is arranged in each of the arc long holes (303) of the three main cutting sleeves (3), the positioning shaft A (9) is fixedly connected with the lifting sleeve (2), the positioning shaft A (9) is abutted on the one side of the arc long hole (303) in the clockwise direction, the compression spring C (14) is arranged between the positioning shaft A (9) and the other side of the arc long hole (303), the positioning shaft B (10), the positioning shaft C (11) and the positioning shaft D (12) are respectively arranged in the radial long holes (402) of the three auxiliary cutting blocks (4) upward and downward, the positioning shaft B (10), the positioning shaft C (11) and the positioning shaft D (12) are fixedly connected with the lifting sleeve (2), the positioning shaft B (10), the positioning shaft C (11) and the positioning shaft D (12) are abutted on the outer side of the radial long hole (402), and the compression spring B (13) is arranged between the positioning shaft B (10), the positioning shaft C (11) and the positioning shaft D (12) and the inner side of the radial long hole (402).

2. A rigid sleeve stabilizer according to claim 1, characterized in that: The lower part of the main cutting sleeve (3) and the auxiliary cutting block (4) of the central pipe (102) is provided with a limiting sleeve (5), and the limiting sleeve (5) and the central pipe (102) are fixedly connected through a pin (7).

3. A rigid sleeve stabilizer according to claim 1, wherein: The outer diameter of the main cutting sleeve (3) and the auxiliary cutting block (4) is the same as the outer diameter of the centralizing sleeve (101).

4. A rigid sleeve stabilizer according to claim 1, wherein: The lifting sleeve (2) and the central pipe (102) are provided with a graphite sleeve (16), the lower end of the graphite sleeve (16) is limited by the stepped hole of the lifting sleeve (2), the upper end of the graphite sleeve (16) is provided with a pressing ring (17), the pressing ring (17) is limited on the upper part of the graphite sleeve (16), and the pressing ring (17) is connected to the upper part of the lifting sleeve (2) through bolts.

5. A rigid sleeve stabilizer according to claim 1, wherein: The connecting thread between the lifting sleeve (2) and the annular counterbore (103) is a non-self-locking thread.

6. A rigid sleeve stabilizer according to claim 1, wherein: The main cutting block (301) is provided with a front inclined surface (3012) and a rear inclined surface (3011) in the counterclockwise direction, and the cutting edge (3013) is formed between the front inclined surface (3012) and the rear inclined surface (3011), and the cutting structure of the auxiliary cutting block (4) is the same as that of the main cutting block (301).

Citation Information

Patent Citations

  • Hydraulic casing centralizer

    CN101942973A

  • Construction operation pipe column applied to oil and natural gas engineering

    CN105221072A

  • Diameter-variable rigid casing centralizer

    CN200978636Y

  • Drilling tool stabilizer with cutting function

    CN209195283U

  • Drill collar stabilizer

    GB851036A

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