Elastic piece prizing type side pushing mechanism for cement sheath crusher

Abstract

The invention is suitable for the field of casing sidetrack drilling operation, and provides an elastic piece prizing type side pushing mechanism for a cement sheath knapper, the elastic piece prizing type side pushing mechanism comprises a first fixing rod, a second fixing rod, an inserting rod, an elastic piece and a movable roller shell, the elastic piece is bent to jack the movable roller shell to do lateral movement, extrusion force is applied to a casing to induce cracking of a cement sheath, and the elastic piece prizing type side pushing mechanism is suitable for the cement sheath knapper. An elastic piece prizing type lateral pushing structure is adopted, an independent driving cavity, a sealing assembly and a guiding structure do not need to be arranged, the structure of the mechanism is greatly simplified, the overall outer diameter size is reduced, miniaturization and compactness of the mechanism are achieved, the mechanism meets the tripping-in requirements of small well diameters, thin-wall sleeves and complex well conditions, meanwhile, lateral extrusion is achieved through elastic deformation of an elastic piece, and the service life of the mechanism is prolonged. Stable extrusion force is guaranteed, and the defects that an existing piston driving structure is complex and large in size are overcome.

Description

Technical Field

[0001] This invention relates to the field of casing side-drilling operations, specifically a spring-loaded pry-type side-push mechanism for cement sheath breakers. Background Technology

[0002] Currently, cement sheath breakers are widely used in wellbore disposal, workover, and isolation operations to apply localized compressive force to the cement sheath on the outside of the casing to induce cement stone cracking, thereby weakening its overall integrity. Due to limitations such as downhole diameter, casing inner diameter, and tool entry space, cement sheath breakers typically need to be compact in structure and have a small outer diameter.

[0003] Because existing cement sheath breakers mostly use piston-driven radial expansion, this type of structure typically requires a separate drive chamber, sealing components, and guiding structure, resulting in a large overall tool size and complex structure. This makes it unsuitable for use in small-diameter wells, thin-walled casings, or complex well conditions. Furthermore, the increased size also increases manufacturing difficulty and assembly complexity, reducing the tool's reliability and adaptability.

[0004] Therefore, there is still a need for a way to achieve the miniaturization and compactness of cement ring crushers while ensuring lateral compression capacity. Summary of the Invention

[0005] The purpose of this invention is to provide a spring-loaded pry-type side-push mechanism for a cement ring crusher to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A spring-loaded pry-type side-pushing mechanism for a cement ring crusher includes: a first fixed rod and a second fixed rod, which are concentrically and coaxially arranged; an insert rod fixed to one end of the first fixed rod, and one end of the second fixed rod having an insertion hole adapted to the insert rod for coaxial guidance and relative sliding of the first and second fixed rods; a spring plate installed between the first and second fixed rods, with both ends of the spring plate rotatably connected to the first and second fixed rods respectively, and capable of bending and protruding under the drive of the relative movement of the first and second fixed rods; and a movable roller housing, which has a columnar structure and is sleeved on the outside of the spring plate, the first fixed rod, and the second fixed rod, with a rectangular hole inside, which provides space for the spring plate to bend and lift; wherein, the bending of the spring plate can lift the movable roller housing to make lateral movement, applying extrusion force to the sleeve to induce the cement ring to crack.

[0007] As a further aspect of the present invention: a pressure roller is fixedly provided at the end of the first fixing rod away from the insertion rod.

[0008] As a further aspect of the present invention: the outer shell of the moving roller has a tapered structure from the center to both ends, and the tapered inclination angle is 3°-5°.

[0009] As a further aspect of the present invention: the spring is made of spring steel, and the middle part of the spring protrudes away from the first fixing rod and the second fixing rod.

[0010] As a further aspect of the present invention: a limiting component is provided at the end of the second fixing rod away from the insertion hole, for fixing the mechanism at a designated position in the wellbore. The limiting component includes a fixing cylinder, a pair of limiting plates and a driving unit. The fixing cylinder is fixedly installed at the end of the second fixing rod, and the pair of limiting plates are movably embedded in the side wall of the fixing cylinder and symmetrically arranged along the diameter direction. The driving unit is used to drive the two limiting plates to perform relative outward expansion or inward contraction movements.

[0011] As a further embodiment of the present invention: the driving unit includes a movable rod, a chassis, multiple electric push rods, and a frustum-shaped driving block; the movable rod is movably inserted into the end of the fixed cylinder, the chassis is fixed to the end of the movable rod located outside the fixed cylinder, and the array of multiple electric push rods is installed between the chassis and the end of the fixed cylinder for driving the movable rod to move axially; the driving block is fixed to the rod body of the movable rod located inside the fixed cylinder, and the two limiting plates have driving grooves with the same taper as the driving block on their sides near the driving block, and the driving block is slidably embedded between the two driving grooves, driving the limiting plates to expand radially through axial movement.

[0012] As a further embodiment of the present invention: a positioning cylinder is also fixedly installed inside the fixed cylinder, the end of the movable rod away from the chassis is movably inserted into the positioning cylinder, and a first spring is provided between the end of the movable rod and the inner wall of the positioning cylinder.

[0013] As a further aspect of the present invention: a groove is provided on the side of the limiting plate away from the fixed cylinder, and an abutment plate is movably arranged in the groove through an elastic unit. An arched rubber pad is provided on the side of the abutment plate away from the elastic unit.

[0014] As a further aspect of the present invention: the elastic unit includes a plurality of positioning protrusions and a second spring; the plurality of positioning protrusions are fixed at equal intervals to the side of the contact plate facing the groove, the inner wall of the groove is provided with a positioning groove that is adapted to be inserted into the positioning protrusion, and the second spring is disposed in the positioning groove and abuts against the end of the positioning protrusion.

[0015] As a further aspect of the present invention, the width of the rectangular hole is greater than the maximum bending protrusion height of the spring sheet.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention adopts a spring-loaded pry-type side-push structure, which eliminates the need for a separate drive cavity, sealing components, and guide structure, greatly simplifying the mechanism structure, reducing the overall outer diameter, and achieving miniaturization and compactness of the mechanism. It is suitable for the running-in requirements of small-diameter, thin-walled casing, and complex well conditions. At the same time, the elastic deformation of the spring achieves lateral extrusion, ensuring stable extrusion force and solving the defects of existing piston-driven structures that are complex and large in size. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a cross-sectional view of the track slab in this invention; Figure 3 This is an enlarged view of the base location in this invention; Figure 4 This is a schematic diagram showing the distribution of the first gear and the second gear in this invention; Figure 5 This is a schematic diagram of the working state in this invention; In the diagram: 1. First fixing rod; 2. Second fixing rod; 3. Insert rod; 4. Insertion hole; 5. Spring piece; 6. Moving roller housing; 7. Rectangular hole; 8. Pressure roller; 9. Fixing cylinder; 10. Limiting plate; 11. Movable rod; 12. Chassis; 13. Electric push rod; 14. Drive block; 15. Drive groove; 16. Positioning cylinder; 17. First spring; 18. Groove; 19. Contact plate; 20. Rubber pad; 21. Positioning protrusion; 22. Positioning groove; 23. Second spring. Detailed Implementation

[0018] The technical solution of this patent will be further described in detail below with reference to specific embodiments.

[0019] Please see Figure 1-5 A spring-loaded pry-type side-pushing mechanism for a cement ring crusher includes: a first fixed rod 1 and a second fixed rod 2, both of which are core load-bearing and transmission components of the mechanism and are arranged concentrically and coaxially; and an insert rod 3, wherein the insert rod 3 is a guide and positioning component, the insert rod 3 is fixed to one end of the first fixed rod 1, and one end of the second fixed rod 2 has an insertion hole 4 that is adapted to the insertion of the insert rod 3, for coaxial guidance and relative sliding of the first fixed rod 1 and the second fixed rod 2, to prevent offset or misalignment when the two move relative to each other, and to ensure transmission stability; Spring piece 5, which is the core lateral pushing force component, is installed between the first fixed rod 1 and the second fixed rod 2. Both ends of the spring piece 5 are rotatably connected to the first fixed rod 1 and the second fixed rod 2 respectively. Driven by the relative movement of the first fixed rod 1 and the second fixed rod 2, it can bend and protrude, converting the axial force into a lateral pushing force, providing power for the extrusion and cracking of the cement ring. The spring piece 5 is made of spring steel, and the middle part of the spring piece 5 protrudes away from the first fixed rod 1 and the second fixed rod 2. Spring steel has excellent elastic deformation capacity and structural strength. The pre-protrusion design in the middle can improve the bending sensitivity and pushing force of the spring piece 5, ensure the output stability of the lateral extrusion force, and extend the service life of the spring piece 5, avoiding the inability to return to its original position after deformation. The movable roller housing 6 has a tapered structure from the center to both ends, with a tapered inclination angle of 3°-5°. The movable roller housing 6 is a lateral extrusion actuator, which is a columnar structure sleeved on the outside of the spring piece 5, the first fixed rod 1 and the second fixed rod 2. A rectangular hole 7 is opened inside it. The width of the rectangular hole 7 is greater than the maximum bending protrusion height of the spring piece 5. This size design provides sufficient room for elastic deformation of the spring piece 5, avoids hard contact between the spring piece 5 and the movable roller housing 6 when the spring piece 5 bends, and prevents structural damage to the spring piece 5 or the movable roller housing 6. The tapered structure reduces the contact resistance when the mechanism is lowered into the well shaft, avoids jamming, and at the same time allows the lateral extrusion force to be applied more evenly to the cement sheath, improving the cracking effect. Among them, the bending of the spring piece 5 can lift the moving roller housing 6 to make lateral movement, and apply extrusion force to the cement sheath to induce cracking. The mechanism adopts a spring piece pry-type side-push structure, which eliminates the need for a separate drive cavity, sealing components and guide structure, greatly simplifying the mechanism structure, reducing the overall outer diameter size, and realizing the miniaturization and compactness of the mechanism. It is suitable for the running requirements of small diameter, thin-walled casing and complex well conditions. At the same time, the lateral extrusion is achieved through the elastic deformation of the spring piece to ensure stable extrusion force, and solves the defects of the existing piston drive structure being complex and large in size.

[0020] The end of the first fixed rod 1 away from the insertion rod 3 is fixedly provided with a pressure roller 8, wherein the pressure roller 8 is a pressure receiving component used to receive the axial pressure of external pressure equipment (such as WDYS-5000 microcomputer-controlled electro-hydraulic servo pressure testing machine).

[0021] In addition, a limiting component is provided at the end of the second fixing rod 2 away from the insertion hole 4. The limiting component is used to fix the mechanism at a designated position in the wellbore to prevent axial movement of the mechanism during operation and to ensure the accuracy of the extrusion cracking operation. The limiting component includes a fixing cylinder 9, a pair of limiting plates 10 and a drive unit. The fixing cylinder 9 is fixedly installed at the end of the second fixing rod 2. The pair of limiting plates 10 are positioning execution components, which are movably embedded in the side wall of the fixing cylinder 9 and symmetrically arranged along the diameter direction. They are fixed by radial expansion and contact with the inner wall of the wellbore. The drive unit is a power drive component used to drive the two limiting plates 10 to perform relative outward expansion or inward contraction movements to achieve rapid fixing and unlocking of the mechanism.

[0022] Specifically, the drive unit includes a movable rod 11, a chassis 12, multiple electric push rods 13, and a frustum-shaped drive block 14. The movable rod 11 is movably inserted into the end of the fixed cylinder 9. The chassis 12 is fixed to the end of the movable rod 11 located outside the fixed cylinder 9. The multiple electric push rods 13 are arrayed and installed between the chassis 12 and the end of the fixed cylinder 9 to drive the movable rod 11 to move axially. The drive block 14 is fixed to the rod body of the movable rod 11 located inside the fixed cylinder 9. Both limiting plates 10 have drive grooves 15 with the same taper as the drive block 14 on their sides near the drive block 14. The drive block 14 is slidably embedded between two drive grooves 15. The drive groove 15 is a sliding guide component of the drive block 14 and is adapted to the conical surface of the drive block 14. It converts the axial movement of the movable rod 11 into the radial movement of the limiting plate 10, causing the limiting plate 10 to expand radially. The axial movement of the movable rod 11 and the drive block 14 is driven by the electric push rod 13. The synchronous radial expansion and contraction of the limiting plate 10 is achieved by using the conical surface cooperation. The structure is compact and easy to operate. It can quickly realize the fixing and unlocking of the mechanism at a specified position in the wellbore and is suitable for the needs of remote control downhole.

[0023] Furthermore, a positioning cylinder 16 is also fixedly installed inside the fixed cylinder 9. The end of the movable rod 11 away from the chassis 12 is movably inserted into the positioning cylinder 16, and a first spring 17 is provided between the end of the movable rod 11 and the inner wall of the positioning cylinder 16. The positioning cylinder 16 is a guide and positioning component for the movable rod 11, used to limit the axial movement trajectory of the movable rod 11 and prevent the movable rod 11 from deviating during movement. The first spring 17 is a reset component, used to drive the movable rod 11 and the drive block 14 to quickly reset when the electric push rod 13 resets, and to assist the retraction of the limiting plate 10.

[0024] Furthermore, the limiting plate 10 has a groove 18 on the side away from the fixed cylinder 9. An abutment plate 19 is movably arranged in the groove 18 through an elastic unit. An arched rubber pad 20 is arranged on the side of the abutment plate 19 away from the elastic unit. The rubber pad 20 is a flexible buffer and friction enhancement component, used to flexibly contact the inner wall of the well cylinder to avoid damage to the inner wall of the well cylinder. At the same time, it increases the friction with the inner wall of the well cylinder and improves the stability of the mechanism after it is fixed. In addition, when the limiting plate 10 is reset and retracted, the rubber pad 19 has less contact with the inner wall of the well cylinder and does not affect the mechanism's continued descent. The elastic unit includes multiple positioning protrusions 21 and a second spring 23. The multiple positioning protrusions 21 are fixed at equal intervals on the side of the contact plate 19 facing the groove 18. The inner wall of the groove 18 is provided with a positioning groove 22 that is adapted to the insertion of the positioning protrusions 21. The second spring 23 is disposed in the positioning groove 22. The cooperation between the positioning protrusions 21 and the positioning groove 22 ensures that the contact plate 19 moves smoothly and avoids displacement. The second spring 23 allows the rubber pad 20 to adapt to the slight undulations of the inner wall of the well shaft and fit tightly against the inner wall, further improving the stability of the mechanism and facilitating the retraction and reset of the limiting plate 10.

[0025] Working principle: When using the spring-loaded pry-type side-push mechanism for cement ring crushers, the entire mechanism is first smoothly lowered into the wellbore by the WDYS-5000 microcomputer-controlled electro-hydraulic servo pressure testing machine until the specified depth for cement ring crushing is reached.

[0026] Subsequently, multiple electric push rods 13 on the chassis 12 are extended and retracted via remote control. When the electric push rods 13 extend, they drive the movable rod 11 to insert into the fixed cylinder 9. The movable rod 11 drives the frustum-shaped drive block 14 to move axially synchronously. The drive block 14 is embedded in the drive groove 15 of the two limiting plates 10. The axial movement is converted into radial force by the conical surface engagement, driving the two limiting plates 10 to expand outward from the fixed cylinder 9 synchronously. During this process, the arched rubber pad 20 on the contact plate 19 first contacts the inner wall of the well. As the limiting plate 10 continues to expand, the second spring 23 is compressed, and the contact plate 19 is embedded into the groove 18 until the limiting plate 10 is in close contact with the inner wall of the well. Under the friction of the rubber pad 20 and the elastic force of the second spring 23, the entire mechanism is stably fixed at the designated position in the well. The positioning cylinder 16 ensures that the movable rod 11 moves smoothly and avoids deviation.

[0027] After the mechanism is fixed, the pressure roller 8 at the end of the first fixed rod 1 is subjected to axial pressure by a pressure testing machine, so that the first fixed rod 1 slides axially relative to the second fixed rod 2. The insertion rod 3 slides synchronously in the insertion hole 4 to ensure that the two move coaxially. At this time, the relative movement of the first fixed rod 1 and the second fixed rod 2 drives the spring piece 5 to bend and bulge. Since the width of the rectangular hole 7 is greater than the maximum bending height of the spring piece 5, the spring piece 5 can deform freely. When the spring piece 5 bends, it lifts the moving roller housing 6 to make lateral movement. The conical structure of the moving roller housing 6 fits against the inner wall of the well barrel and applies a uniform lateral extrusion force to the cement sheath, thereby inducing the cement stone to crack and realizing the cement sheath breaking operation.

[0028] After the operation is completed, the remote-controlled electric push rod 13 is reset, the movable rod 11 moves in the opposite direction under the action of the first spring 17, the drive block 14 disengages from the drive groove 15, and the two limit plates 10 are re-embedded into the fixed cylinder 9 under the reset force of the second spring 23 and the action of the rubber pad 20. Since the rubber pad 20 is arched, the contact area with the inner wall of the well after reset is extremely small, which will not hinder the mechanism from going deeper into the well, making it easier to carry out subsequent operations.

[0029] The entire mechanism adopts a spring-loaded pry-type side-push structure, eliminating the need for complex drive cavities and sealing components. It features a compact structure and small outer diameter, making it suitable for small-diameter wells, thin-walled casings, and complex well conditions. It is also easy to operate and stable, effectively solving the problems of complex structure, large size, and poor adaptability of existing cement sheath breakers.

[0030] The installation, connection, or setting methods disclosed in this embodiment are all common mechanical connection methods. Any method that can achieve its beneficial effect can be implemented. In addition, the electrical components in this embodiment are all electrically connected to the main controller and the power supply. The main controller can be a conventional known device such as a computer that plays a control role. Those skilled in the art can control the electrical components through simple programming. Moreover, the existing disclosed power connection technology is also common knowledge in the field. Therefore, the specific structural composition and working principle will not be described in detail in this embodiment.

Claims

1. A spring-loaded pry-type side-push mechanism for a cement ring crusher, characterized in that, include: The first fixing rod (1) and the second fixing rod (2) are set concentrically and coaxially. Insert rod (3), the insert rod (3) is fixed to one end of the first fixing rod (1), and one end of the second fixing rod (2) is provided with an insertion hole (4) that is compatible with the insertion rod (3) for coaxial guidance and relative sliding of the first fixing rod (1) and the second fixing rod (2); The spring piece (5) is installed between the first fixed rod (1) and the second fixed rod (2), and the two ends of the spring piece (5) are rotatably connected to the first fixed rod (1) and the second fixed rod (2) respectively. It can bend and protrude due to the relative movement of the first fixed rod (1) and the second fixed rod (2). The movable roller housing (6) is in the form of a columnar structure and is sleeved on the outside of the spring piece (5), the first fixing rod (1) and the second fixing rod (2). A rectangular hole (7) is provided inside the spring piece (5) to provide space for bending and lifting. Among them, the bending of the spring piece (5) can lift the outer shell of the moving roller (6) to make lateral movement, and apply extrusion force to the sleeve to induce the cement ring to crack.

2. The spring-loaded pry-type side-push mechanism for a cement ring crusher according to claim 1, characterized in that, A pressure roller (8) is fixedly provided at the end of the first fixing rod (1) away from the insertion rod (3).

3. The spring-loaded pry-type side-push mechanism for a cement ring crusher according to claim 1, characterized in that, The housing of the moving roller (6) has a tapered structure from the center to both ends, with a tapered inclination angle of 3°-5°.

4. The spring-loaded pry-type side-push mechanism for a cement ring crusher according to claim 1, characterized in that, The spring piece (5) is made of spring steel, and the middle part of the spring piece (5) protrudes away from the first fixing rod (1) and the second fixing rod (2).

5. The spring-loaded pry-type side-push mechanism for a cement ring crusher according to claim 1, characterized in that, The second fixing rod (2) is provided with a limiting component at one end away from the insertion hole (4) for fixing the mechanism at a specified position in the well barrel. The limiting component includes a fixing cylinder (9), a pair of limiting plates (10) and a driving unit. The fixed cylinder (9) is fixedly installed at the end of the second fixed rod (2). A pair of limiting plates (10) are movably embedded in the side wall of the fixed cylinder (9) and symmetrically arranged along the diameter direction. The driving unit is used to drive the two limiting plates (10) to perform relative outward expansion or inward contraction movements.

6. The spring-loaded pry-type side-push mechanism for a cement ring crusher according to claim 5, characterized in that, The drive unit includes a movable rod (11), a chassis (12), multiple electric push rods (13), and a frustum-shaped drive block (14). The movable rod (11) is movably inserted into the end of the fixed cylinder (9), and the chassis (12) is fixed to the end of the movable rod (11) located outside the fixed cylinder (9). A plurality of electric push rods (13) are arrayed between the chassis (12) and the end of the fixed cylinder (9) to drive the movable rod (11) to move axially. The drive block (14) is fixed to the rod body of the movable rod (11) located inside the fixed cylinder (9). The two limiting plates (10) are provided with drive grooves (15) with the same taper as the drive block (14) on their sides near the drive block (14). The drive block (14) is slidably embedded between the two drive grooves (15) and drives the limiting plates (10) to expand radially through axial movement.

7. The spring-loaded pry-type side-push mechanism for a cement ring crusher according to claim 6, characterized in that, A positioning cylinder (16) is also fixedly installed inside the fixed cylinder (9). The end of the movable rod (11) away from the chassis (12) is movably inserted into the positioning cylinder (16), and a first spring (17) is provided between the end of the movable rod (11) and the inner wall of the positioning cylinder (16).

8. The spring-loaded pry-type side-push mechanism for a cement ring crusher according to claim 5, characterized in that, The limiting plate (10) has a groove (18) on the side away from the fixed cylinder (9). An abutment plate (19) is movably arranged in the groove (18) through an elastic unit. An arched rubber pad (20) is provided on the side of the abutment plate (19) away from the elastic unit.

9. The spring-loaded pry-type side-push mechanism for a cement ring crusher according to claim 8, characterized in that, The elastic unit includes multiple positioning protrusions (21) and a second spring (23); The plurality of positioning protrusions (21) are fixed at equal intervals on the side of the contact plate (19) facing the groove (18). The inner wall of the groove (18) is provided with a positioning groove (22) that is compatible with the positioning protrusions (21). The second spring (23) is disposed in the positioning groove (22) and abuts against the end of the positioning protrusion (21).

10. The spring-loaded pry-type side-push mechanism for a cement ring crusher according to claim 1, characterized in that, The width of the rectangular hole (7) is greater than the maximum bending protrusion height of the spring piece (5).

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