Elastic clamp salvaging mechanism, elastic clamp salvaging inner assembly and wire-line coring drilling tool

Abstract

The invention discloses an elastic clamp salvaging mechanism, an elastic clamp salvaging inner assembly and a rope coring drilling tool. The elastic clamp salvaging mechanism comprises an inner pipe, a salvaging spear mechanism and at least one group of elastic clamp mechanism, an inner pipe with a top opening is arranged in the inner pipe, and the spear mechanism can axially reciprocate in the inner pipe; the elastic clamping mechanism comprises an elastic clamping plate and a spring piece, the spring piece is fixed to the inner wall face of the inner pipe, in the unfolding state, the top of the elastic clamping plate extends out of the containing groove and can be clamped into a limiting structure on the inner wall of the outer pipe assembly so as to limit axial movement of the inner pipe relative to the outer pipe assembly, and in the folding state, the elastic clamping plate is folded into the containing groove so as to limit axial movement of the inner pipe relative to the outer pipe assembly. The inner pipe can axially move in the outer pipe assembly; the fishing spear mechanism can apply pressure to the inner side wall of the elastic clamping plate and enables the elastic clamping plate to overcome the pressure of the spring piece to be changed into the folded state from the unfolded state; therefore, the device can improve the reliability and the working efficiency of wire-line coring drilling operation.

Description

Technical Field

[0001] This invention relates to the field of geological exploration technology, and in particular to a trolley retrieval mechanism, a trolley retrieval internal assembly, and a wireline coring tool. Background Technology

[0002] In existing conventional wireline coring and retrieval mechanisms, the core functional components of the retrieval mechanism mostly include paired retrieval plates and tension springs (opening springs). Relying on the radial preload provided by the tension springs, the two retrieval plates are driven to open outwards and engage with the retrieval chamber of the outer assembly, thereby achieving axial limiting and circumferential locking of the inner assembly during drilling. During the retrieval operation, the retrieval mechanism drives the retrieval plates to overcome the tension spring force and retract inwards, releasing the engagement and locking with the retrieval chamber, thus completing the unlocking and retrieval of the inner assembly.

[0003] In existing structures, the springs are mostly assembled using a simple method where the hooks at both ends are directly hooked into the mounting holes of the spring clip, without a dedicated anti-detachment limiting structure. The reliability of the connection between the spring and the spring clip depends entirely on the structural strength of the hooks themselves and the fit. However, wireline coring drilling is mostly used in deep hard rock and complex fractured strata. During drilling, the drill bit is continuously subjected to high-frequency rotational vibration and alternating axial pressure impact loads. At the same time, the high-speed circulating flushing fluid and the rock powder particles it carries in the hole will continuously erode and abrade the connection points of the springs. In addition, during the retrieval operation, the spring clip is repeatedly closed and opened, and the spring is frequently subjected to alternating compression and rebound stress. This can easily cause fatigue deformation and wear enlargement of the hook part of the spring, ultimately leading to the failure of the fit between the hook and the mounting hole, causing the spring to fall off.

[0004] The detachment of the spring can directly trigger a series of serious drilling failures: First, without the radial preload support of the spring, the spring plate cannot reliably open and engage with the outer assembly spring chamber, causing complete failure of the axial limiting of the inner assembly. During drilling, the inner assembly moves upward with the core feed, causing core blockage, wear and breakage, and a significant decrease in core recovery rate. In severe cases, it can lead to serious in-hole accidents such as core tube bending, breakage, or even stuck drill bit. Second, the spring plate cannot maintain a stable open state and cannot form a proper engagement with the outer assembly's fork structure. Reliable engagement can lead to circumferential positioning failure of the inner assembly, preventing synchronous rotation of the inner and outer assemblies and interrupting the torque transmission of the drill string, thus hindering normal drilling operations. Thirdly, detached tension springs can fall into the internal flow channels of the drill string or the bottom of the hole, easily causing blockage of the flushing fluid flow channels and jamming of the retrieval mechanism, resulting in failure to retrieve the inner assembly. Drilling must be stopped and the entire drill string must be pulled out for handling, significantly increasing non-productive operation time, severely reducing the construction efficiency of deep drilling, and significantly increasing the construction cost and safety risks of drilling operations. Summary of the Invention

[0005] The purpose of this invention is to provide a spring-loaded retrieval mechanism, a spring-loaded retrieval inner assembly, and a wireline coring tool to solve the problems existing in the prior art, ensure that the inner assembly can be reliably fixed to the outer assembly, and can be smoothly opened or closed during retrieval, thereby improving the reliability and efficiency of wireline coring operations.

[0006] To achieve the above objectives, the present invention provides the following solution: This invention provides a spring-loaded retrieval mechanism, including a spear-lifting mechanism and at least one set of spring-loaded mechanisms. The lower end of the spear-lifting mechanism is disposed inside an inner tube and is capable of axial reciprocating within the inner tube. The spring-loaded mechanism includes a spring-loaded plate and a spring plate. A receiving groove communicating between the inside and outside of the inner tube is formed on the side wall of the inner tube. The spring plate is fixed to the inner wall surface of the inner tube. The spring-loaded plate is movably connected to the inner tube and has an extended state and a retracted state. In the extended state, the top of the spring-loaded plate extends out of the receiving groove and can... The inner tube is engaged within the limiting structure on the inner wall of the outer tube assembly to restrict the axial movement of the inner tube relative to the outer tube assembly. In the retracted state, the spring plate retracts into the receiving groove, allowing the inner tube to move axially within the outer tube assembly. The spring plate applies pressure to the upper edge of the spring plate and keeps the spring plate in the extended state. The spear-retrieving mechanism is lifted axially along the inner tube. The spear-retrieving mechanism applies pressure to the inner wall of the spring plate and causes the spring plate to overcome the pressure of the spring plate and change from the extended state to the retracted state.

[0007] In some embodiments, a rotating column is integrally formed on each of the two opposite sidewalls of the spring plate, and a groove is formed on each of the two opposite inner wall surfaces of the receiving groove. The rotating column extends into the groove and can rotate within the groove so that the spring plate and the inner tube form a rotatable connection.

[0008] In some embodiments, the spring clip mechanism further includes a fixing block, the spring sheet having at least one positioning hole, the fixing block having a positioning protrusion matching the positioning hole, the fixing block being fixedly connected to the inner tube and pressing the spring sheet between the inner wall of the inner tube and the fixing block, the positioning protrusion passing through the corresponding positioning hole to limit the displacement of the spring sheet in the length direction of the inner tube.

[0009] In some embodiments, a limiting part is also fixedly provided on the spring plate, which can abut against the edge of the receiving groove on the inner wall of the inner tube to limit the maximum angle at which the spring plate opens outward.

[0010] In some embodiments, the spear-retrieving mechanism includes a spearhead, a shaft, and an elastic element. At least the lower part of the shaft is located inside the inner tube, and the upper end of the shaft is connected to the spearhead. The elastic element is sleeved on the outside of the shaft and located inside the inner tube. From top to bottom, the lower part of the shaft is provided with an outwardly protruding pressing boss and a lower limiting boss. The inner tube wall above the lower limiting boss protrudes outward to form an upper limiting boss. The upper end of the elastic element abuts against the lower end face of the upper limiting boss, and the lower end of the elastic element abuts against the upper end face of the lower limiting boss. Lifting the spearhead causes the shaft to move upward synchronously, and the pressing boss presses against the inner wall of the lower end of the spring-loaded plate, causing the spring-loaded plate to rotate around the rotating column to the retracted state. When the spearhead is lowered, the elastic element pushes the shaft downward to reset, causing the pressing boss to disengage from the spring-loaded plate, and the spring-loaded plate resets to the unfolded state under the action of the spring plate.

[0011] In some embodiments, the shaft is rotatable relative to the inner tube about the axis of the inner tube.

[0012] In some embodiments, one end of the inner tube is provided with an end cap, which covers the top opening of the inner tube. The lower end of the end cap extends into the inner tube and abuts against the top of the fixing block to restrict the upward movement of the fixing block.

[0013] In some embodiments, the end cap has a central hole, the spearhead is inserted into the central hole, the inner wall of the central hole is in contact with the outer wall of the spearhead, and the axis of the spearhead, the axis of the central hole and the axis of the inner tube are collinear.

[0014] The present invention also provides an inner assembly for a spring-loaded retrieval device, comprising an inner tube, a core inner tube, and the spring-loaded retrieval mechanism described in any one of the above-mentioned embodiments, wherein the lower end of the inner tube is fixedly connected to the upper end of the core inner tube by a connector.

[0015] The present invention also provides a wireline coring tool, including an outer tube assembly and the aforementioned spring-loaded retrieval inner assembly. The outer tube assembly is sleeved on the outside of the inner tube and the core inner tube. The inner wall of the outer tube assembly is provided with a limiting structure that engages with the spring-loaded plate. The limiting structure is a limiting groove.

[0016] The present invention achieves the following technical effects compared to the prior art: This invention features an axially reciprocating spear-retrieval mechanism and a spring-loaded pre-tightening plate within the inner tube. The continuous pre-tightening force of the spring ensures the axial fixation of the spring-loaded plate to the outer tube assembly's limiting structure in its unfolded state, providing reliable reverse support for drilling and coring operations. Fixing the spring to the inner tube within the inner tube effectively prevents it from detaching. Furthermore, the spring-loaded plate can be simultaneously retracted and unlocked by simply lifting the spear-retrieval mechanism, significantly improving the efficiency of downhole retrieval operations for wireline coring tools. In addition, the device's structural design reduces vulnerable parts and transmission links, effectively avoiding downhole jamming and disengagement failure risks. It is also simple to use, highly safe, and suitable for various complex well conditions. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the deployed state structure of the spring-loaded retrieval mechanism in one embodiment of Example 1. Figure 2 This is a schematic diagram of the retracted state structure of the spring-loaded retrieval mechanism in one embodiment of Example 1; Figure 3 This is a schematic diagram of the structure of the spring-loaded retrieval mechanism in one embodiment of Example 1; Figure 4 This is a schematic diagram of the spring plate in one embodiment of Example 1.

[0019] Wherein: 1-Spearhead; 2-End cap; 3-Shaft; 4-Fixing block; 5-Spring sheet; 7-Spring clamp plate; 8-Elastic element; 9-Inner tube; 10-Positioning protrusion; 11-Outer tube assembly; 12-Spring clamp retrieval mechanism; 14-Setting screw; 15-Limiting part; 16-Rotating column. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Example 1 This invention provides a cartridge retrieval mechanism 12, such as... Figure 1-4 As shown, the device includes a spear-retrieving mechanism and at least one set of spring-loaded mechanisms. The lower end of the spear-retrieving mechanism is located inside the inner tube 9 and can reciprocate axially within the inner tube 9. The spring-loaded mechanism includes a spring-loaded plate 7 and a spring plate 5. A receiving groove communicating between the inside and outside of the inner tube 9 is provided on the side wall of the inner tube 9. The spring plate 5 is fixed to the inner wall surface of the inner tube 9. The spring-loaded plate 7 is used to movably connect with the inner tube 9 and has an extended state and a retracted state. In the extended state, the top of the spring-loaded plate 7 extends out of the receiving groove and can be engaged with the limiting structure on the inner wall of the outer tube assembly 11 to restrict the axial movement of the inner tube 9 relative to the outer tube assembly 11. In the retracted state, the spring-loaded plate 7 retracts into the receiving groove, allowing the inner tube 9 to move axially within the outer tube assembly 11. The spring plate 5 can apply pressure to the upper edge of the spring-loaded plate 7 and keep the spring-loaded plate 7 in the extended state, lifting the spear-retrieving mechanism axially along the inner tube 9. Pressure is applied to the inner wall of the spring clip 7, causing the spring clip 7 to overcome the pressure of the spring plate 5 and change from the unfolded state to the retracted state. In this embodiment, by setting an axially reciprocating spear-retrieval mechanism and a spring clip 7 with a spring plate 5 pre-tightening structure inside the inner tube 9, the continuous pre-tightening force of the spring plate 5 ensures the axial fixation of the spring clip 7 with the limiting structure of the outer tube assembly 11 in the unfolded state, providing reliable reverse support for drilling and coring operations. Fixing the spring plate 5 to the inner tube inside the inner tube 9 can effectively prevent the spring plate 5 from falling off. At the same time, the retraction and unlocking of the spring clip 7 can be completed simultaneously by simply lifting the spear-retrieval mechanism, which greatly improves the efficiency of downhole retrieval operations of wireline coring tools. In addition, the structural design of this device reduces vulnerable parts and transmission links, effectively avoiding the risk of downhole jamming and disengagement failure. It is also simple to use, has high operational safety, and is suitable for various complex well conditions.

[0023] In some embodiments of this example, rotating columns 16 are integrally formed on the two opposite side walls of the spring-loaded plate 7, and grooves are formed on the two opposite inner walls of the receiving groove. The rotating columns 16 extend into the grooves and can rotate within the grooves to form a rotatable connection between the spring-loaded plate 7 and the inner tube 9. The cross-sections of the rotating columns 16 and the grooves are both elongated ovals, and the width of the groove cross-section is greater than the width of the rotating column 16 cross-section. During installation, the rotating columns 16 of the spring-loaded plate 7 are placed into the grooves, and after the spring-loaded plate 7 extends into the receiving groove, it cannot come out of the grooves. Therefore, this device does not require additional pins or locking mechanisms. The attachments and other loose parts fundamentally avoid the downhole failure risks that are prone to occur with traditional pin-and-pin hinges, such as parts falling off, cuttings getting stuck in sand, and corrosion seizing. The one-piece molded structure avoids structural weakening and stress concentration of the spring clip plate body, greatly improving the load-bearing strength and fatigue resistance of the hinge support point. At the same time, it significantly reduces the precision requirements for parts processing and the difficulty of assembly and on-site operation and maintenance. Moreover, the structure is completely built-in and does not occupy additional radial space, perfectly adapting to the narrow installation conditions of wireline coring drills downhole. Overall, it significantly improves the operational reliability, action stability and adaptability of the spring clip retrieval mechanism.

[0024] In some embodiments of this example, the spring clip mechanism further includes a fixing block 4. The spring sheet 5 has at least one positioning hole, and the fixing block 4 is provided with a positioning protrusion 10 that matches the positioning hole. The fixing block 4 is fixedly connected to the inner tube 9 and presses the spring sheet 5 between the inner wall surface of the inner tube 9 and the fixing block 4. The positioning protrusion 10 passes through the corresponding positioning hole to limit the displacement of the spring sheet 5 in the length direction of the inner tube 9. This achieves full-dimensional displacement constraint of the spring sheet 5 in the radial, circumferential, and axial directions, completely avoiding the fatal failure risk of slippage, misalignment, or even detachment of the spring sheet under the traditional single screw fixing method due to the influence of downhole high-frequency vibration and drilling fluid erosion. It ensures that the spring sheet 5 can continuously and stably apply pre-tightening force to the spring clip plate 7. At the same time, the cooperation between the positioning protrusion 10 and the positioning hole can also realize rapid pre-positioning during assembly without repeated alignment and calibration, which significantly reduces the difficulty of assembly and on-site maintenance and replacement of parts and improves work efficiency. The fixing block is fixed to the inner tube 9 by bolts 14.

[0025] In some embodiments of this example, a limiting part 15 is also fixedly provided on the spring-loaded plate 7. The limiting part 15 can abut against the edge of the receiving groove located on the inner wall of the inner tube 9 to limit the maximum angle at which the spring-loaded plate 7 opens outward. This avoids interference, jamming, or inability to retract and reset smoothly due to excessive outward opening. At the same time, it can effectively prevent the spring-loaded plate 7 from deforming or breaking due to excessive elastic force applied by the spring plate 5, ensuring that it is always in a reliable and stable working angle. This ensures accurate engagement with the outer tube limiting structure and smooth return to its original position when squeezed by the spear-finding mechanism, thereby improving the consistency of the overall mechanism's actions and the reliability of downhole operations.

[0026] In some embodiments of this example, the spear-catching mechanism includes a spearhead 1, a shaft 3, and an elastic element 8. At least the lower part of the shaft 3 is located inside the inner tube 9, and the upper end of the shaft 3 is connected to the spearhead 1. The elastic element 8 is sleeved on the outside of the shaft 3 and located inside the inner tube 9. From top to bottom, the lower part of the shaft 3 is provided with an outwardly protruding extrusion boss and a lower limiting boss. The inner tube 9 has an outwardly protruding wall surface above the lower limiting boss to form an upper limiting boss. The upper end of the elastic element 8 abuts against the upper limiting boss. The lower end face of the boss, and the lower end of the elastic element 8 abuts against the upper end face of the lower limit boss; lifting the spearhead 1 can drive the shaft 2 to move upward synchronously, and cause the pressing boss to press the inner side wall of the lower end of the spring plate 7, so that the spring plate 7 rotates around the protrusion to the retracted state; when lowering the spearhead 1, the elastic element 8 can push the shaft 3 to move downward and reset, so that the pressing boss disengages from the spring plate 7, and the spring plate 7 resets to the unfolded state under the action of the spring plate 5; through the shaft 3 and the spearhead 1 The coordinated operation enables the shaft 3 to move upward simultaneously when the spearhead 1 is lifted, and the spring-loaded plate 7 to retract and unlock by squeezing the extrusion boss. When the spearhead 1 is lowered, the shaft 3 is automatically lowered and reset by the elastic thrust of the elastic element 8, and the extrusion boss is disengaged from the spring-loaded plate 7. The spring-loaded plate 7 is then automatically deployed in conjunction with the spring plate 5. The precise switching of the state of the spring-loaded plate 7 can be completed without additional operation, which greatly simplifies the operation process of the retrieval operation and improves the efficiency of the operation. At the same time, the design of the upper and lower limit bosses provides a stable installation limit and force transmission benchmark for the elastic element 8, ensuring the continuous and stable output of the elastic reset force. It can also accurately limit the axial reciprocating stroke of the shaft 3, avoiding problems such as incomplete extrusion and over-limit reset caused by over-extrusion of the shaft 3. This ensures the precise controllability of the retraction and deployment of the spring-loaded plate and significantly improves the operational stability and operational reliability of the spring-loaded retrieval mechanism 12 under complex downhole conditions.

[0027] In some embodiments of this example, the shaft 3 can rotate relative to the inner tube 9 around the axis of the inner tube 9. By rotating, the torsional stress generated during the lowering and retrieval of the retrieval wire rope is fully released, thus avoiding downhole accidents such as retrieval failure and tool falling into the well caused by wire rope kinking, twisting, or even breakage. At the same time, it can adapt to circumferential angle deviation when the retrieval spearhead 1 is engaged with the downhole retrieval docking structure, eliminating the need for repeated drilling and retrieval adjustments to adjust the alignment, greatly improving the success rate of retrieval docking on the first attempt. It can also effectively isolate the rotational torque transmitted by the inner tube 9 and the outer tube assembly 11 during drilling or drilling and retrieval, preventing the torque from being transmitted in reverse to the retrieval wire rope and internal parts of the mechanism, reducing the risk of parts wear and jamming, ensuring the smooth and stable unfolding and retraction of the spring-loaded clamp 7, and significantly improving the operational safety, working condition adaptability, operational reliability, and service life of the spring-loaded clamp retrieval mechanism 12.

[0028] In some embodiments of this example, an end cap 2 is provided at one end of the inner tube 9. The end cap 2 covers the top opening of the inner tube 9, and the lower end of the end cap 2 extends into the inner tube 13 and abuts against the top of the fixing block 4 to restrict the upward movement of the fixing block 4. The end cap 2 is threadedly connected to the inner tube 9. The rigid abutment between the end cap 2 and the fixing block 4 forms a stable axial limit, which can effectively resist the displacement risk caused by downhole high-frequency vibration and fishing impact load, completely eliminate the problem of the fixing block 4 loosening and moving upward, causing the spring plate 5 to lose its clamping fixation and the spring clamp plate 7 to fail its pre-tightening function, and ensure the continuous, stable and reliable operation of the spring clamp mechanism. At the same time, the end cap 2 can completely seal the top opening of the inner tube 9, effectively blocking rock cuttings, sand particles and other impurities in the drilling fluid from entering the inner tube 9, avoiding the problems of sand entry jamming, wear and corrosion of the internal shaft 3 and elastic element 8, and greatly extending the overall service life of the mechanism. The fixing block 4 and the end cap 2 can also be combined into one part and fixedly connected to the inner tube 9 by a set screw.

[0029] In some embodiments of this example, a central hole is provided in the center of the end cap 2, and the spearhead 1 is inserted into the central hole. The inner wall of the central hole fits against the outer wall of the spearhead 1, and the axis of the spearhead 1, the axis of the central hole, and the axis of the inner tube 9 are collinear. The coaxial structure provides precise radial limiting and coaxial guidance for the axial reciprocating movement of the spearhead 1, which can effectively resist the radial sway and shaking caused by downhole high-frequency vibration and fishing impact load, ensuring that the spearhead 1 and the shaft 3 always make precise axial movements along the axis of the inner tube 9, and ensuring that the extrusion protrusion on the shaft 3 can synchronously and evenly extrude the inner sidewall of each spring-loaded plate 7, completely avoiding problems such as incomplete extrusion on one side, asynchronous movement of the spring-loaded plates 7, and jamming failure caused by uneven load, greatly improving the consistency and reliability of the state switching of the spring-loaded plates 7, and further improving the action stability, operational reliability, and working condition adaptability of the spring-loaded fishing mechanism 12 in complex downhole operating environments.

[0030] Example 2 This embodiment provides an inner assembly for a spring-loaded retrieval system, including an inner tube 9, a core inner tube, and the spring-loaded retrieval mechanism 12 from Embodiment 1. The lower end of the inner tube 9 is fixedly connected to the upper end of the core inner tube via a connector. A suspension mechanism, a single-action mechanism, and an adjustable spacing mechanism are also provided between the lower end of the inner tube 9 and the upper end of the core inner tube. This embodiment utilizes a retrieval spear mechanism capable of axial reciprocating movement and a spring-loaded plate 7 with a pre-tightening structure of spring plates 5 within the inner tube 9. The continuous pre-tightening force of the spring plates 5 ensures that the spring-loaded plate 7 remains in contact with the outer tube assembly in its unfolded state. The axial fixation of the 11 limiting structure provides reliable reverse support for drilling and coring operations. Fixing the spring plate 5 to the inner tube inside the inner tube 9 effectively prevents the spring plate 5 from falling off. At the same time, the spring clip 7 can be retracted and unlocked simultaneously by simply lifting the retrieval spear mechanism, which greatly improves the efficiency of downhole retrieval operations of wireline coring tools. In addition, the structural design of this device reduces vulnerable parts and transmission links, effectively avoiding the risks of downhole jamming and disengagement failure. It is also simple to use, has high operational safety, and is suitable for various complex well conditions.

[0031] Example 3 This embodiment provides a wireline coring tool, including an outer tube assembly 11 and a spring-loaded retrieval inner assembly as described in Embodiment 2. The outer tube assembly 11 is sleeved on the outside of the inner tube 9 and the inner core tube. The inner wall of the outer tube assembly 11 is provided with a limiting structure that engages with the spring-loaded retrieval plate 7, wherein the limiting structure is a limiting groove. In commonly used spring-loaded retrieval mechanisms, during the opening and positioning process of the spring-loaded retrieval plate, there is a probability that the spring-loaded retrieval plate and the fork on the outer assembly will jam directly against each other, preventing the spring-loaded retrieval plate from opening normally and failing to form an effective upper limit constraint. The above problems can cause the inner assembly to be unreliably fixed inside the outer assembly, or retrieval failure during retrieval, seriously affecting the continuity and reliability of drilling operations, reducing operational efficiency, and may even lead to accidents such as core loss and drill bit damage. This embodiment features an axially reciprocating spear-retrieval mechanism and a spring-loaded clamping plate 7 with a pre-tightening structure of spring plate 5 within the inner tube 9. The continuous pre-tightening force of the spring plate 5 ensures the axial fixation of the spring-loaded clamping plate 7 to the limiting structure of the outer tube assembly 11 in the unfolded state, providing reliable reverse support for drilling and coring operations. Fixing the spring plate 5 to the inner tube within the inner tube 9 effectively prevents the spring plate 5 from falling off. Simultaneously, the spring-loaded clamping plate 7 can be retracted and unlocked simultaneously by simply lifting the spear-retrieval mechanism, significantly improving the efficiency of downhole retrieval operations for wireline coring tools. In addition, the structural design of this device reduces vulnerable parts and transmission links, effectively avoiding the risks of downhole jamming and disengagement failure. It is also simple to use, highly safe in operation, and suitable for various complex well conditions.

[0032] Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this invention. Furthermore, those skilled in the art will recognize that, based on the ideas of this invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this invention.

Claims

1. A cartridge-based retrieval mechanism, characterized in that: It includes a spear-retrieval mechanism and at least one set of spring-loaded mechanisms; the lower end of the spear-retrieval mechanism is disposed inside the inner tube and is capable of axial reciprocating within the inner tube; The spring-loaded mechanism includes a spring-loaded plate and a spring plate. A receiving groove communicating between the inside and outside of the inner tube is formed on the side wall of the inner tube. The spring plate is fixed to the inner wall surface of the inner tube. The spring-loaded plate is movably connected to the inner tube and has an extended state and a retracted state. In the extended state, the top of the spring-loaded plate extends out of the receiving groove and can engage with a limiting structure on the inner wall of the outer tube assembly to restrict the axial movement of the inner tube relative to the outer tube assembly. In the retracted state, the spring-loaded plate retracts into the receiving groove, allowing the inner tube to move axially within the outer tube assembly. The spring plate applies pressure to the upper edge of the spring-loaded plate to keep it in the extended state and lifts the spear-retrieving mechanism axially along the inner tube. The spear-retrieving mechanism applies pressure to the inner wall of the spring-loaded plate, causing the spring-loaded plate to overcome the pressure of the spring plate and change from the extended state to the retracted state.

2. The cartridge retrieval mechanism according to claim 1, characterized in that: Rotating columns are integrally formed on the two opposite side walls of the spring plate, and grooves are formed on the two opposite inner wall surfaces of the receiving groove. The rotating columns extend into the grooves and can rotate within the grooves to form a rotatable connection between the spring plate and the inner tube.

3. The cartridge retrieval mechanism according to claim 1, characterized in that: The spring clip mechanism further includes a fixing block. The spring sheet has at least one positioning hole. The fixing block has a positioning protrusion that matches the positioning hole. The fixing block is fixedly connected to the inner tube and presses the spring sheet between the inner wall of the inner tube and the fixing block. The positioning protrusion passes through the corresponding positioning hole to limit the displacement of the spring sheet in the length direction of the inner tube.

4. The cartridge retrieval mechanism according to claim 1 or 3, characterized in that: The spring plate is also fixedly provided with a limiting part, which can abut against the edge of the receiving groove on the inner wall of the inner tube to limit the maximum angle at which the spring plate opens outward.

5. The cartridge retrieval mechanism according to claim 2, characterized in that: The spear-catching mechanism includes a spearhead, a shaft, and an elastic element. At least the lower part of the shaft is located inside the inner tube, and the upper end of the shaft is connected to the spearhead. The elastic element is sleeved on the outside of the shaft and located inside the inner tube. From top to bottom, the lower part of the shaft has a protruding pressing boss and a lower limiting boss. The inner tube wall above the lower limiting boss protrudes to form an upper limiting boss. The upper end of the elastic element abuts against the lower end face of the upper limiting boss, and the lower end of the elastic element abuts against the upper end face of the lower limiting boss. Lifting the spearhead causes the shaft to move upwards synchronously, and the pressing boss presses against the inner wall of the lower end of the spring-loaded plate, causing the spring-loaded plate to rotate around the rotating column to the retracted state. When the spearhead is lowered, the elastic element pushes the shaft downwards to reset, causing the pressing boss to disengage from the spring-loaded plate, and the spring-loaded plate resets to the unfolded state under the action of the spring plate.

6. The cartridge retrieval mechanism according to claim 5, characterized in that: The shaft is capable of rotating relative to the inner tube about the axis of the inner tube.

7. The cartridge retrieval mechanism according to claim 6, characterized in that: One end of the inner tube is provided with an end cap, which covers the top opening of the inner tube. The lower end of the end cap extends into the inner tube and abuts against the top of the fixing block to restrict the upward movement of the fixing block.

8. The cartridge retrieval mechanism according to claim 7, characterized in that: The end cap has a central hole, and the spearhead is inserted into the central hole. The inner wall of the central hole fits against the outer wall of the spearhead, and the axis of the spearhead, the axis of the central hole, and the axis of the inner tube are collinear.

9. A type of ammunition-mounted salvage internal assembly, characterized in that: It includes an inner tube, a core inner tube, and a spring-loaded retrieval mechanism as described in any one of claims 1-8, wherein the lower end of the inner tube is connected to the upper end of the core inner tube via a connector.

10. A wireline coring tool, characterized in that: The device includes an outer tube assembly and the spring-loaded retrieval inner assembly as described in claim 9. The outer tube assembly is sleeved on the outside of the inner tube and the core inner tube. The inner wall of the outer tube assembly is provided with a limiting structure that engages with the spring-loaded plate. The limiting structure is a limiting groove.

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