Rock breaking drilling tool for oil exploitation

Abstract

The invention discloses a rock breaking drilling tool for oil exploitation, and particularly relates to the technical field of oil exploitation, the drilling tool comprises a drill rod assembly, a drill bit assembly is arranged at the bottom end of the drill rod assembly, and a drilling fluid inlet is formed in the middle of the top of the drill rod assembly; a self-resetting impact piston is slidably connected into the drill rod assembly, the drill bit assembly is installed at the bottom end of the self-resetting impact piston, and a third axial hole is formed in the self-resetting impact piston. A self-resetting impact piston is connected into the drill rod assembly in a sliding mode, and a second axial hole is formed in the self-resetting impact piston. A pressure distribution assembly is installed in the drill rod assembly, a plunger is installed at the bottom of the pressure distribution assembly, and a pressure cavity is defined by the self-resetting impact piston, the drill rod assembly and the pressure distribution assembly. The drill bit assembly is internally provided with a first axial hole, a flow-out hole, a drilling fluid inlet, the pressure distribution assembly, the second axial hole, the third axial hole, the first axial hole and the flow-out hole which are sequentially communicated. Through cooperation of double-piston series connection impact and periodic liquid flow control, composite rock breaking of hydraulic impact and rotation is achieved.

Description

Technical Field

[0001] This invention relates to the field of oil extraction technology, specifically to a rock breaking drill for oil extraction. Background Technology

[0002] In oil extraction, especially in drilling operations through hard formations (such as shale and granite), rock breaking efficiency directly affects drilling speed, cost, and drill bit life. Traditional rotary drilling tools rely primarily on the rotation of the drill bit and static pressure loads to break rocks. For high-hardness, highly abrasive formations, this breaking method is inefficient. Furthermore, if the drill bit cannot sufficiently break the rock in front of it during drilling, it may affect the oil extraction results and may even cause the drill bit to jam. Therefore, sufficient rock breaking is necessary to ensure the smooth progress of oil extraction. To address these issues, we propose a rock breaking drill for oil extraction. Summary of the Invention

[0003] The purpose of this invention is to provide a rock breaking drill for oil extraction, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution: a rock breaking drill for oil exploration, comprising a drill pipe assembly, a drill bit assembly at the bottom end of the drill pipe assembly, the interior of the drill pipe assembly being hollow, and a drilling fluid inlet at the top center of the drill pipe assembly; The bottom of the drill rod assembly is slidably connected to a self-resetting impact piston, which can rotate synchronously with the drill rod assembly. The drill bit assembly is installed at the bottom of the self-resetting impact piston, and the self-resetting impact piston has an axial hole through the middle. The drill pipe assembly is slidably connected to the upper section of the self-resetting impact piston, and the self-resetting impact piston has an axial hole through the middle. A pressure distribution assembly is installed in the upper section of the self-resetting impact piston inside the drill pipe assembly. A plunger is installed in the middle of the bottom of the pressure distribution assembly. A pressure chamber is formed by the top of the self-resetting impact piston, the inner wall of the drill pipe assembly, and the pressure distribution assembly. The drill bit assembly has an axial hole 1 and an outlet hole that are interconnected. The drilling fluid inlet, pressure distribution assembly, axial hole 2, axial hole 3, axial hole 1, and outlet hole are connected in sequence. The plunger can extend into the interior of axial hole 2 to block axial hole 2 and drive the water flow in the pressure chamber to push the self-resetting impact piston to impact the self-resetting shock piston.

[0005] Preferably, the self-resetting impact piston, the self-resetting impact piston and the drill bit assembly are provided with an auxiliary flow channel that can be connected in series to form a complete flow channel. The top of the self-resetting impact piston is provided with a threshold valve assembly that communicates with the auxiliary flow channel. The threshold valve assembly opens when the self-resetting impact piston is stuck and the plunger blocks the axial hole two. The tail end of the auxiliary flow channel is on the drill bit assembly. The tail end of the auxiliary flow channel is slidably connected to a secondary crushing assembly that blocks the auxiliary flow channel. The tail end of the auxiliary flow channel is provided with a liquid outlet, which is connected to an axial hole. One end of the secondary crushing component extends out of the drill bit assembly. When the secondary crushing component is in its initial state, it blocks the liquid outlet. The liquid outlet opens after the water flow pushes the secondary crushing component out of the drill bit assembly. The secondary crushing component extends out to crush rocks.

[0006] Preferably, the inner wall of the drill pipe assembly is provided with a centrifugal unlocking component, which is used to restrict the sliding of the self-resetting impact piston when the drill pipe assembly stops rotating. The centrifugal unlocking component unlocks when the drill pipe assembly rotates and locks when the drill pipe assembly stops rotating.

[0007] Preferably, the drill bit assembly consists of a central base, primary breaking teeth, and secondary breaking teeth; The primary crushing tooth is installed on the outside of the central base to form a large crushing tooth, and the secondary crushing tooth is installed on the outside of the primary crushing tooth to form a small crushing tooth; One end of the secondary crushing component extends outward from the outside of the primary crushing tooth, and the extension length is less than the extension length of the secondary crushing tooth. The central matrix is ​​provided with a first flow channel, which serves as the tail section of the auxiliary flow channel.

[0008] Preferably, the self-resetting impact piston includes a central shaft, a lower connecting seat, a first reset elastic element, and a connecting seat; The central shaft has an axial hole three in the middle, and a connecting seat and a lower connecting seat are respectively installed at the upper and lower ends of the central shaft. The lower connecting seat is threaded to the top end of the central base. The outer sides of the lower connecting seat and the connecting seat are in contact with the inner wall of the drill pipe assembly. A support ring is installed between the inner walls of the drill pipe assembly and the lower connecting seat. There is a gap between the inner ring of the support ring and the outer wall of the central shaft. The upper and lower ends of the first reset elastic element abut against the bottom of the connecting seat and the top of the support ring, respectively; The central shaft, the lower connecting seat, and the connecting seat together form a third flow channel. The third flow channel forms the middle section of the auxiliary flow channel. The top end of the third flow channel is connected to the top of the connecting seat, and the bottom end of the third flow channel is connected to the first flow channel.

[0009] Preferably, a groove is radially formed around the inner side of the support ring, and a pressure relief hole communicating with the bottom of the support ring is formed in the groove; The centrifugal unlocking assembly includes a locking block and a second reset elastic element; The locking block is slidably connected in the slide groove, and the two ends of the second reset elastic member are respectively connected to the end of the locking block in the slide groove and the inner wall of the slide groove. The locking block extends to seal the gap between the support ring and the central shaft.

[0010] Preferably, the pressure distribution assembly includes a retaining sleeve and a flow divider; The diverter is installed on the inner wall of the drill pipe assembly. The bottom of the diverter is connected to the fixed sleeve, and the top of the fixed sleeve is located in the middle of the diverter. A bypass hole is opened on the outer periphery of the diverter, which is connected to the inside of the diverter and the pressure chamber.

[0011] Preferably, the self-resetting impact piston includes a piston body and a third reset elastic element; An annular groove is provided in the middle of the outer periphery of the piston body, and both the upper and lower ends of the piston body are in contact with the inner wall of the drill rod assembly. The drill pipe assembly has a positioning ring installed on the inner wall of the annular groove, and there is a gap between the positioning ring and the annular groove. The upper and lower ends of the third reset elastic member abut against the inner top of the annular groove and the top of the positioning ring, respectively. The inner wall of the piston body is provided with a second flow channel, which constitutes the first section of the auxiliary flow channel, and the bottom end of the second flow channel is engaged with the top end of the third flow channel when the self-resetting impact piston and the self-resetting shock piston come into contact.

[0012] Preferably, the threshold valve assembly includes a valve core, a fourth reset elastic element, and a valve seat; The valve core is slidably connected to the top of the piston body along the axial direction, and forms a sealed control cavity with the piston body. The upper and lower ends of the fourth reset elastic element are respectively connected to the bottom of the valve core and the bottom of the control cavity. A valve seat is installed at the top of the second flow channel. A side hole communicating with the second flow channel is opened on the outer side wall of the valve seat. The valve core is movably sleeved on the outside of the valve seat and separates the pressure chamber from the side hole. The side hole communicates with the pressure chamber after the valve core moves down.

[0013] Preferably, the secondary crushing assembly includes an impact head, a piston rod, and a fifth reset elastic element; The impact head is connected to the piston rod, and the piston rod is adapted to the inner diameter of the first flow channel to block the liquid outlet; The fifth reset elastic element is sleeved on the outside of the impact head, and the two ends of the fifth reset elastic element are respectively connected to the inner wall of the first flow channel and the outer periphery of the end connecting the piston rod and the impact head.

[0014] Compared with the prior art, the beneficial effect of this invention is that, if possible, more details can be written, or one point can be split into multiple points, trying to make a total of ten points: 1. This oilfield drilling tool utilizes a rock-breaking drill string. Through the combination of a dual-piston tandem impact structure and periodic fluid flow control (pressure distribution components and plungers), it efficiently converts the hydraulic energy of conventional drilling fluid into high-frequency, high-energy axial impact force on the drill bit, achieving a composite rock-breaking mode of "hydraulic impact + rotation". Compared to pure rotary drilling, this mode can more effectively induce fatigue fracturing in hard rock, significantly improving the mechanical drilling rate. It features a compact structure, a power source directly derived from the drilling fluid, requires no additional surface equipment, and boasts high integration and reliability.

[0015] 2. This oilfield utilizes rock-breaking drill bits and introduces an auxiliary rock-breaking system (including auxiliary flow channels, threshold valve assemblies, and secondary breaking components) with intelligent sensing and switching functions. This solves the problem of localized stubborn rock obstructing drilling in hard rock wells. The system can automatically detect when the drill bit is stuck and switch the fluid flow path, concentrating high-pressure energy to a retractable impact head for secondary impact on the obstacle point. This dual rock-breaking mechanism of "mainly breaking the overall rock and globally breaking the rock + auxiliary pinpoint clearing the obstacle" greatly enhances the drill bit's adaptability to complex formations and its ability to handle downhole anomalies, effectively preventing stuck drill accidents and ensuring the continuity, safety, and efficiency of drilling operations. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art 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.

[0017] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a cross-sectional structural diagram of the present invention; Figure 3 This is a partial cross-sectional structural schematic diagram of the present invention; Figure 4 This is a cross-sectional view of another part of the structure of the present invention; Figure 5 This is a schematic diagram of the drill bit assembly in this invention; Figure 6This is a schematic diagram showing the cross-sectional view of the centrifugal unlocking component in this invention; Figure 7 This is a schematic diagram of the connection structure of the secondary crushing component in this invention; Figure 8 In this invention Figure 4 A schematic diagram of the structure at point A in the middle.

[0018] In the diagram: 1. Drill pipe assembly; 11. Support ring; 12. Positioning ring; 101. Drilling fluid inlet; 102. Auxiliary flow channel. The parts inside the drill pipe assembly are labeled 101, 102, etc. It's best to avoid using 11, 12, etc., and use 10X for all parts. The same applies to the following labels. 2. Drill bit assembly; 21. Central base; 22. Primary breaking tooth; 23. Secondary breaking tooth; 201. Axial hole one; 202. Liquid outlet; 203. Flow outlet; 204. First flow channel; 3. Pressure distribution assembly; 31. Fixing sleeve; 32. Diverter; 301. Bypass hole; 4. Plunger; 5. Self-resetting impact piston; 51. Piston body; 52. Third reset elastic element; 501. Axial hole two; 502. Second flow channel; 503. Control cavity; 6. Self-resetting impact piston; 61. Central shaft; 62. Lower connecting seat; 63. First reset elastic element; 64. Connecting seat; 601. Axial hole three; 602. Third flow channel; 603. Slide groove; 604. Pressure relief hole; 7. Threshold valve assembly; 71. Valve core; 72. Fourth reset elastic element; 73. Valve seat; 701. Side hole; 8. Centrifugal unlocking assembly; 81. Lock block; 82. Second reset elastic element; 9. Secondary crushing assembly; 91. Impact head; 92. Piston rod; 93. Fifth reset elastic element. Detailed Implementation

[0019] 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.

[0020] Example: Figure 1-8 As shown, the present invention provides the following technical solution: a rock breaking drill for oil exploration, including a drill pipe assembly 1, a drill bit assembly 2 at the bottom end of the drill pipe assembly 1, the interior of the drill pipe assembly 1 being hollow, and a drilling fluid inlet 101 at the top center of the drill pipe assembly 1; The bottom of the drill rod assembly 1 is slidably connected to a self-resetting impact piston 6, and the self-resetting impact piston 6 can rotate synchronously with the drill rod assembly 1. The drill bit assembly 2 is installed at the bottom of the self-resetting impact piston 6, and an axial hole 601 is opened through the middle of the self-resetting impact piston 6. A self-resetting impact piston 5 is slidably connected to the upper section of the self-resetting impact piston 6 inside the drill pipe assembly 1. An axial hole 501 is opened through the middle of the self-resetting impact piston 5. A pressure distribution assembly 3 is installed in the upper section of the self-resetting impact piston 5 inside the drill pipe assembly 1. A plunger 4 is installed in the middle of the bottom of the pressure distribution assembly 3. A pressure chamber is formed by the top of the self-resetting impact piston 5, the inner wall of the drill pipe assembly 1, and the pressure distribution assembly 3. The drill bit assembly 2 has an axial hole 201 and an outlet hole 203 that are connected to each other. The drilling fluid inlet 101, the pressure distribution assembly 3, the axial hole 501, the axial hole 601, the axial hole 201 and the outlet hole 203 are connected in sequence. The plunger 4 can extend into the interior of the axial hole 501 to block the axial hole 501 and drive the water flow in the pressure chamber to push the self-resetting impact piston 5 to impact the self-resetting impact piston 6.

[0021] By adopting the above technical solution, this invention constructs a dual-piston tandem, drilling fluid-driven composite impact system. The drill pipe assembly 1 serves as a channel for transmitting torque and drilling fluid (high-pressure mud). The drilling fluid is pumped in from the top drilling fluid inlet 101. The core rock-breaking power originates from the self-resetting impact piston 5 and the self-resetting impact piston 6. The pressure distribution assembly 3 (whose core function is to distribute the fluid flow) and the plunger 4 constitute a periodic fluid flow control valve. The basic working principle is as follows: After the drilling fluid flows through the pressure distribution assembly 3, it flows into the pressure chamber. The lower end of the plunger 4 extends into and blocks the axial hole 501 of the self-resetting impact piston 5, thus blocking the upstream fluid flow path. At this time, the liquid pressure in the "pressure chamber" formed between the top of the self-resetting impact piston 5, the inner wall of the drill pipe assembly 1, and the bottom of the pressure distribution assembly 3 rises sharply because it cannot flow downwards. This high pressure pushes the self-resetting impact piston 5 to overcome its reset force (such as spring force) and move downwards at high speed, striking the self-resetting impact piston 6 below like a heavy hammer. The self-resetting impact piston 6 transfers the kinetic energy of this impact to the drill bit assembly 2, which is rigidly connected to it, thereby applying a strong axial impact to the bottom rock. When the impact is completed, the plunger 4 moves away, the axial hole 501 opens, the pressure chamber is depressurized, and the drilling fluid flows. The self-resetting impact piston 5 returns to its initial position under the action of its reset mechanism (such as a spring), preparing for the next impact. At the same time, the self-resetting impact piston 6 also returns to its original position under the action of its reset mechanism. This cycle continues, forming a high-frequency impact on the drill bit. Throughout the process, after completing its impact driving function, the drilling fluid continues to flow through the axial hole 201 and the outflow hole 203 inside the drill bit, serving to cool the drill bit and carry away rock cuttings. Furthermore, driven by the rotation of the drill pipe assembly 1, the drill bit assembly 2 can rotate to break the rock. This "dual-in-one" design achieves impact-rotation drilling, resulting in more efficient and thorough rock breaking.

[0022] Furthermore, the self-resetting impact piston 5, the self-resetting impact piston 6, and the drill assembly 2 are provided with an auxiliary flow channel 102 that can be connected in series to form a complete flow channel. The top of the self-resetting impact piston 5 is provided with a threshold valve assembly 7 that communicates with the auxiliary flow channel 102. The threshold valve assembly 7 is opened when the self-resetting impact piston 5 is stuck and the plunger 4 blocks the axial hole 2 501. The tail end of the auxiliary flow channel 102 is on the drill bit assembly 2. The tail end of the auxiliary flow channel 102 is slidably connected to a secondary crushing assembly 9 that blocks the auxiliary flow channel 102. The tail end of the auxiliary flow channel 102 is provided with a liquid outlet 202, which is connected to the axial hole 201. One end of the secondary crushing component 9 extends out of the drill bit assembly 2. When the secondary crushing component 9 is in its initial state, it blocks the liquid outlet 202. The liquid outlet 202 opens after the water flow pushes the secondary crushing component 9 out of the drill bit assembly 2, and the secondary crushing component 9 extends out to crush the rock.

[0023] By adopting the above technical solution, an intelligent switching "auxiliary rock breaking system" is introduced. In addition to the active rock breaking system (drill bit assembly 2, self-resetting impact piston 5, and self-resetting impact piston 6), an independent "auxiliary flow channel 102" is provided. This flow channel runs through the self-resetting impact piston 5, the self-resetting impact piston 6, and the drill bit assembly 2. However, under normal circumstances (i.e., when the active rock breaking system is working normally and the self-resetting impact piston 5 can move freely back and forth), it does not function because the threshold valve assembly 7 is in the closed state, blocking the high-pressure drilling fluid from entering the auxiliary flow channel 102. Intelligent switching mechanism: When an abnormal situation occurs at the bottom of the well, such as when the drill bit assembly 2 (along with the self-resetting impact piston 6) is temporarily "stuck" and its downward movement is obstructed, the upper self-resetting impact piston 5, after completing one downward strike, will also be "blocked" because the lower self-resetting impact piston 6 cannot descend smoothly, or its downward stroke is abnormally shortened. This "stuck" state causes the position of the self-resetting impact piston 5 relative to the inner wall of the drill pipe assembly 1 to change. This abnormal position triggers the opening condition of the threshold valve assembly 7. When it "detects" that the self-resetting impact piston 5 is in a "stuck" state, and at the same time the plunger 4 blocks the axial hole 2 501 (i.e., the pressure chamber is building pressure), the threshold valve assembly 7 opens. Auxiliary Impact Initiation: Once the threshold valve assembly 7 opens, the high-pressure drilling fluid no longer merely acts on the pressure chamber to push the self-resetting impact piston 5 for a "useless" short-stroke impact (because it is stuck below), but instead flows into the auxiliary flow channel 102 through the newly opened channel. The high-pressure fluid flow quickly reaches the tail end inside the drill bit assembly 2 along the auxiliary flow channel 102, acting on the secondary fracturing component 9. Driven by the high-pressure fluid flow, the secondary fracturing component 9 overcomes its reset force (such as spring force) and quickly extends outward from the drill bit assembly 2. Its extended end directly impacts the stubborn rock that has not been sufficiently broken in front of or to the side of the drill bit assembly 2, performing a precise and powerful "auxiliary impact" or "secondary fracturing". After the impact is completed, the fluid flow merges into the main fluid flow channel (axial hole 201) through the outlet 202 at the tail end of the opened auxiliary flow channel 102, and finally exits from the outlet hole 203. Once the stubborn rock is broken, the drill bit regains freedom, the self-resetting impact piston 5 can reset normally, the threshold valve assembly 7 closes, and the system switches back to the main impact mode. This design enables intelligent adaptive switching of rock-breaking modes, concentrating energy to solve localized difficulties.

[0024] Furthermore, the inner wall of the drill pipe assembly 1 is provided with a centrifugal unlocking component 8. The centrifugal unlocking component 8 is used to restrict the sliding of the self-resetting impact piston 6 when the drill pipe assembly 1 stops rotating. The centrifugal unlocking component 8 unlocks when the drill pipe assembly 1 rotates and locks when the drill pipe assembly 1 stops rotating.

[0025] By adopting the above technical solution, a centrifugal unlocking component 8 is added. The function of the centrifugal unlocking component 8 is to automatically lock the self-resetting impact piston 6 after self-resetting when the drill bit stops rotating (e.g., when it gets stuck), thereby activating the above-mentioned "auxiliary rock breaking system" to perform a precise and powerful "auxiliary impact" or "secondary breaking" on the stubborn rock that has not been sufficiently broken in front of or to the side of the drill bit assembly 2. When the drill rod assembly 1 starts to rotate, the centrifugal force generated acts on the centrifugal unlocking component 8, thereby releasing the constraint on the self-resetting impact piston 6, allowing it to freely perform impact reciprocating motion.

[0026] Furthermore, the drill bit assembly 2 consists of a central base 21, a primary breaking tooth 22, and a secondary breaking tooth 23; The primary crushing tooth 22 is installed on the outside of the central base 21 to form a large crushing tooth, and the secondary crushing tooth 23 is installed on the outside of the primary crushing tooth 22 to form a small crushing tooth; One end of the secondary crushing component 9 extends out from the outside of the primary crushing tooth 22, and the extension length is less than the extension length of the secondary crushing tooth 23. The central substrate 21 is provided with a first flow channel 204, which serves as the tail section of the auxiliary flow channel 102.

[0027] By adopting the above technical solution, the structure of drill bit assembly 2 is specified. A composite tooth structure is used: the primary breaking tooth 22 (large tooth) undertakes the main cutting and impact breaking tasks; the secondary breaking tooth 23 (small tooth) is located outside the large tooth, serving to assist in breaking, trim the well wall, and increase tooth density. The secondary breaking assembly 9 extends from the side or root region of the primary breaking tooth 22, and its extension length is designed to be shorter than that of the secondary breaking tooth 23, preventing the secondary breaking assembly 9 from contacting the bottom rock and avoiding unnecessary wear. It only extends additionally under hydraulic pressure when auxiliary impact is needed to perform targeted impact. The first flow channel 204 is a channel machined inside the central matrix 21 to guide the high-pressure fluid flow to the secondary breaking assembly 9.

[0028] Furthermore, the self-resetting impact piston 6 includes a central shaft 61, a lower connecting seat 62, a first reset elastic element 63, and a connecting seat 64; The central shaft 61 has an axial hole 601 in the middle. The upper and lower ends of the central shaft 61 are respectively equipped with a connecting seat 64 and a lower connecting seat 62. The lower connecting seat 62 is threadedly connected to the top end of the central base 21. The outer sides of both the lower connecting seat 62 and the connecting seat 64 are in contact with the inner wall of the drill pipe assembly 1. A support ring 11 is installed between the inner walls of the drill pipe assembly 1 and the lower connecting seat 62 and the connecting seat 64. There is a gap between the inner ring of the support ring 11 and the outer wall of the central shaft 61. The upper and lower ends of the first reset elastic member 63 abut against the bottom of the connecting seat 64 and the top of the support ring 11, respectively. The central shaft 61, the lower connecting seat 62, and the connecting seat 64 are all provided with a third flow channel 602. The third flow channel 602 forms the middle section of the auxiliary flow channel 102. The top end of the third flow channel 602 is connected to the top of the connecting seat 64, and the bottom end of the third flow channel 602 is connected to the first flow channel 204.

[0029] The self-resetting impact piston 6 is described in detail using the above technical solution. It is a combined piston structure: the central shaft 61 is the core force transmission component, with an axial bore 601 inside for the main fluid flow. The lower connecting seat 62 is used to connect the drill bit assembly 2, and the connecting seat 64 is located at the top. The first reset elastic element 63 (such as a large spring) provides the rebound force of the self-resetting impact piston 6 after being impacted. The support ring 11 is fixed to the inner wall of the drill rod, providing radial support and axial movement guidance for the entire piston assembly. The gap between it and the central shaft 61 is used for pressure relief. The third flow channel 602 is a complex channel machined inside the central shaft 61, the lower connecting seat 62, and the connecting seat 64. It is used to transport high-pressure fluid in auxiliary mode, guiding the auxiliary fluid from above to the first flow channel 204 inside the drill bit.

[0030] Furthermore, a groove 603 is radially provided on the inner side of the support ring 11, and a pressure relief hole 604 communicating with the bottom of the support ring 11 is provided in the groove 603. Centrifugal unlocking assembly 8 includes a locking block 81 and a second reset elastic element 82; The locking block 81 is slidably connected in the slide groove 603, and the two ends of the second reset elastic member 82 are respectively connected to the end of the locking block 81 in the slide groove 603 and the inner wall of the slide groove 603. The locking block 81 extends to seal the gap between the support ring 11 and the central shaft 61.

[0031] By adopting the above technical solution, the specific implementation method of the centrifugal unlocking component 8 is revealed. The locking block 81 is a wedge-shaped block that can slide within the radial groove 603 of the support ring 11; the second reset elastic element 82 (such as a spring) provides a centripetal (inward) thrust to the locking block 81. When the drill rod is stationary, the spring force causes the locking block 81 to extend inward, with its inner end tightly against the outer wall of the central shaft 61, sealing the gap between the support ring 11 and the central shaft 61, thus separating the support ring 11 and the central shaft 61 into two parts. The pressure of the two parts acts on the central shaft 61, thereby radially locking the central shaft 61 and preventing it from sliding up and down, achieving "locking". The pressure relief hole 604 is used to balance the back pressure of the locking block 81. When the drill rod rotates at high speed, the locking block 81 is subjected to centrifugal force, overcoming the spring force of the second reset elastic element 82 and being thrown outward, disengaging from the contact with the central shaft 61, restoring the gap, and "unlocking" the self-resetting impact piston 6.

[0032] Furthermore, the pressure distribution assembly 3 includes a fixed sleeve 31 and a distributor 32; The diverter 32 is installed on the inner wall of the drill pipe assembly 1. The bottom of the diverter 32 is connected to the fixed sleeve 31, and the top of the fixed sleeve 31 is located in the middle of the diverter 32. A bypass hole 301 is provided on the outer periphery of the diverter 32, which is connected to the interior of the diverter 32 and the pressure chamber.

[0033] The above technical solution describes the fluid distribution mechanism of the main impact system. The distributor 32 and the fixed sleeve 31 form a relatively fixed distribution structure. The bypass hole 301 is a channel connecting the internal flow channels of the distributor 32 and the fixed sleeve 31 with the external annular pressure chamber, ensuring the relative balance of axial fluid flow.

[0034] Furthermore, the self-resetting impact piston 5 includes a piston body 51 and a third reset elastic element 52; An annular groove is provided in the middle of the outer periphery of the piston body 51, and both the upper and lower ends of the piston body 51 are in contact with the inner wall of the drill rod assembly 1. A positioning ring 12 is installed on the inner wall of the drill pipe assembly 1 in the annular groove, and there is a gap between the positioning ring 12 and the annular groove. The upper and lower ends of the third reset elastic member 52 abut against the inner top of the annular groove and the top of the positioning ring 12, respectively. The inner wall of the piston body 51 is provided with a second flow channel 502, which constitutes the first section of the auxiliary flow channel 102. The bottom end of the second flow channel 502 is engaged with the top end of the third flow channel 602 when the self-resetting impact piston 5 and the self-resetting impact piston 6 come into contact.

[0035] The detailed structure of the self-resetting impact piston 5 is described by adopting the above technical solution. The upper and lower ends of the piston body 51 are in sealed sliding contact with the inner wall of the drill pipe assembly 1, and the cooperation between the intermediate annular groove and the positioning ring 12 forms a guiding and limiting structure for the piston movement. The third reset elastic element 52 (such as a spring) is installed in the annular groove, with its upper end abutting against the piston body 51 and its lower end abutting against the fixed positioning ring 12, providing the reset force after impact for the self-resetting impact piston 5. The second flow channel 502 is a channel machined inside the piston body 51, serving as the starting part of the auxiliary flow channel 102. Its bottom end is designed to connect with the inlet of the third flow channel 602 at the top of the self-resetting impact piston 6 below. When the self-resetting impact piston 5 descends to contact the self-resetting impact piston 6 (i.e., completes the main impact), the two flow channels are precisely connected, creating a path for the high-pressure fluid flow to be transmitted from the self-resetting impact piston 5 to the self-resetting impact piston 6 in the auxiliary mode.

[0036] Furthermore, the threshold valve assembly 7 includes a valve core 71, a fourth reset elastic element 72, and a valve seat 73; The valve core 71 is slidably connected to the top of the piston body 51 along the axial direction, and forms a closed control cavity 503 between the valve core 71 and the piston body 51. The upper and lower ends of the fourth reset elastic member 72 are respectively connected to the bottom of the valve core 71 and the inner bottom of the control cavity 503. A valve seat 73 is installed at the top of the second flow channel 502. A side hole 701 communicating with the second flow channel 502 is opened on the outer side wall of the valve seat 73. The valve core 71 is movably sleeved on the outside of the valve seat 73 and separates the pressure chamber from the side hole 701. The side hole 701 communicates with the pressure chamber after the valve core 71 moves down.

[0037] By adopting the above technical solution, the working principle of the intelligent switching valve—threshold valve assembly 7 is explained in detail. The valve core 71, the fourth reset elastic element 72, and the valve seat 73 constitute a pressure-position sensitive valve. Under normal circumstances, the valve core 71 is in the upper position supported by the fourth reset elastic element 72 (spring), and its lower end sealing surface covers the side hole 701 of the valve seat 73, completely separating the high-pressure chamber from the second flow channel 502 (auxiliary flow channel inlet); Triggering Process: When the self-resetting impact piston 5 is stuck from below, and the plunger 4 blocks the axial hole 501 to build up pressure, the pressure in the pressure chamber will rise abnormally (because the piston cannot descend to release pressure). This abnormally high pressure acts on the pressure-bearing surface (top) of the valve core 71, overcoming the preload of the fourth reset elastic element 72 and pushing the valve core 71 downward. After the valve core 71 moves downward, its lower sealing surface leaves the side hole 701 of the valve seat 73, thereby allowing the high-pressure chamber to connect with the second flow channel 502 through the opened side hole 701. The high-pressure liquid flow then rushes into the auxiliary flow channel 102, activating the auxiliary impact mode; the control chamber 503 plays the role of pressurizing and regulating the threshold for pushing the valve core 71 downward.

[0038] Furthermore, the secondary crushing assembly 9 includes an impact head 91, a piston rod 92, and a fifth reset elastic element 93; The impact head 91 is connected to the piston rod 92, and the piston rod 92 is adapted to the inner diameter of the first flow channel 204 to block the liquid outlet 202. The fifth reset elastic element 93 is sleeved on the outside of the impact head 91. The two ends of the fifth reset elastic element 93 are respectively connected to the inner wall of the first flow channel 204 and the outer periphery of the connection end between the piston rod 92 and the impact head 91.

[0039] The above technical solution describes a terminal mechanism for performing auxiliary impact. The impact head 91 acts as an impact hammer. A fifth reset elastic element 93 (such as a spring) provides a reset force, keeping the secondary crushing assembly 9 in a retracted state when not in operation. At this time, the piston rod 92 blocks the outlet 202, preventing a short circuit in the liquid flow. When high-pressure liquid flows from the auxiliary flow channel 102 into the first flow channel 204, it acts on the pressure-bearing surface of the piston rod 92, pushing the entire assembly (impact head 91 and piston rod 92) and the fifth reset elastic element 93 to extend rapidly outwards. The impact head 91 directly impacts the rock. After the impact, the liquid flows out from the opened outlet 202, the pressure drops, and the fifth reset elastic element 93 pulls the secondary crushing assembly 9 back to its original position, re-blocking the outlet 202, preparing for the next action.

[0040] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A rock-breaking drilling tool for oil extraction, comprising a drill pipe assembly (1), wherein a drill bit assembly (2) is provided at the bottom end of the drill pipe assembly (1), characterized in that: The drill pipe assembly (1) is hollow inside, and a drilling fluid inlet (101) is provided at the top center of the drill pipe assembly (1). The bottom sliding connection inside the drill rod assembly (1) is achieved by a self-resetting impact piston (6), which can rotate synchronously with the drill rod assembly (1). The drill bit assembly (2) is installed at the bottom of the self-resetting impact piston (6), and an axial hole (601) is provided through the middle of the self-resetting impact piston (6). The drill rod assembly (1) is slidably connected to the upper section of the self-resetting impact piston (6), and the self-resetting impact piston (5) has an axial hole (501) through the middle. The drill pipe assembly (1) is equipped with a pressure distribution component (3) located in the upper section of the self-resetting impact piston (5). A plunger (4) is installed in the middle of the bottom of the pressure distribution component (3). The top of the self-resetting impact piston (5), the inner wall of the drill pipe assembly (1), and the pressure distribution component (3) form a pressure chamber. This can be marked in the figure. For people who are not professionals, they may not know which part it refers to. The drill bit assembly (2) has an axial hole 1 (201) and an outlet hole (203) that are connected to each other. The drilling fluid inlet (101), pressure distribution assembly (3), axial hole 2 (501), axial hole 3 (601), axial hole 1 (201), and outlet hole (203) are connected in sequence. The plunger (4) can extend into the interior of axial hole 2 (501) to block axial hole 2 (501) and drive the water flow in the pressure chamber to push the self-resetting impact piston (5) to impact the self-resetting impact piston (6).

2. The rock breaking drill bit for oil extraction according to claim 1, characterized in that: The self-resetting impact piston (5), the self-resetting impact piston (6) and the drill assembly (2) are provided with an auxiliary flow channel (102) that can be connected in series. The top of the self-resetting impact piston (5) is provided with a threshold valve assembly (7) that communicates with the auxiliary flow channel (102). The threshold valve assembly (7) opens when the self-resetting impact piston (5) is stuck and the plunger (4) blocks the axial hole two (501). The tail end of the auxiliary flow channel (102) is on the drill bit assembly (2). The tail end of the auxiliary flow channel (102) is slidably connected to a secondary crushing assembly (9) that blocks the auxiliary flow channel (102). The tail end of the auxiliary flow channel (102) is provided with a liquid outlet (202), which is connected to the axial hole (201). One end of the secondary crushing component (9) extends out of the drill bit assembly (2). When the secondary crushing component (9) is in the initial state, it blocks the liquid outlet (202). The liquid outlet (202) opens after the water flow pushes the secondary crushing component (9) out of the drill bit assembly (2). The secondary crushing component (9) extends out to crush the rock.

3. The rock breaking drill bit for oil extraction according to claim 2, characterized in that: The inner wall of the drill pipe assembly (1) is provided with a centrifugal unlocking component (8). The centrifugal unlocking component (8) is used to restrict the sliding of the self-resetting impact piston (6) when the drill pipe assembly (1) stops rotating. The centrifugal unlocking component (8) unlocks when the drill pipe assembly (1) rotates and locks when the drill pipe assembly (1) stops rotating.

4. The rock breaking drill bit for oil extraction according to claim 3, characterized in that: The drill bit assembly (2) consists of a central base (21), primary breaking teeth (22), and secondary breaking teeth (23); The primary crushing tooth (22) is installed on the outside of the central base (21) to form a large crushing tooth, and the secondary crushing tooth (23) is installed on the outside of the primary crushing tooth (22) to form a small crushing tooth; One end of the secondary crushing component (9) extends out from the outside of the primary crushing tooth (22), and the extension length is less than the extension length of the secondary crushing tooth (23); The central substrate (21) is provided with a first flow channel (204), which serves as the tail section of the auxiliary flow channel (102).

5. The rock breaking drill bit for oil extraction according to claim 4, characterized in that: The self-resetting impact piston (6) includes a central shaft (61), a lower connecting seat (62), a first reset elastic element (63), and a connecting seat (64). The central shaft (61) has an axial hole three (601) in the middle. The upper and lower ends of the central shaft (61) are respectively equipped with a connecting seat (64) and a lower connecting seat (62). The lower connecting seat (62) is threadedly connected to the top end of the central base (21). The outer sides of the lower connecting seat (62) and the connecting seat (64) are in contact with the inner wall of the drill rod assembly (1). A support ring (11) is installed between the inner walls of the lower connecting seat (62) and the connecting seat (64) of the drill rod assembly (1). There is a gap between the inner ring of the support ring (11) and the outer wall of the central shaft (61). The upper and lower ends of the first reset elastic member (63) abut against the bottom of the connecting seat (64) and the top of the support ring (11), respectively; The central shaft (61), the lower connecting seat (62), and the connecting seat (64) are all provided with a third flow channel (602). The third flow channel (602) forms the middle section of the auxiliary flow channel (102). The top end of the third flow channel (602) is connected to the top of the connecting seat (64), and the bottom end of the third flow channel (602) is connected to the first flow channel (204).

6. The rock breaking drill bit for oil extraction according to claim 5, characterized in that: The inner side of the support ring (11) is provided with a radial groove (603), and a pressure relief hole (604) communicating with the bottom of the support ring (11) is provided in the groove (603). The centrifugal unlocking assembly (8) includes a locking block (81) and a second reset elastic element (82); The locking block (81) is slidably connected in the slide groove (603), and the two ends of the second reset elastic member (82) are respectively connected to the end of the locking block (81) in the slide groove (603) and the inner wall of the slide groove (603); The locking block (81) extends to seal the gap between the support ring (11) and the central shaft (61).

7. The rock breaking drill bit for oil extraction according to claim 6, characterized in that: The pressure distribution assembly (3) includes a fixed sleeve (31) and a distributor (32); The diverter (32) is installed on the inner wall of the drill pipe assembly (1). The bottom of the diverter (32) is connected to the fixed sleeve (31), and the top of the fixed sleeve (31) is located in the middle of the diverter (32). A bypass hole (301) is provided on the outer periphery of the diverter (32) and communicates with the interior of the diverter (32) and the pressure chamber.

8. The rock breaking drill bit for oil extraction according to claim 7, characterized in that: The self-resetting impact piston (5) includes a piston body (51) and a third reset elastic element (52). The piston body (51) has an annular groove in the middle of its outer periphery, and both the upper and lower ends of the piston body (51) are in contact with the inner wall of the drill rod assembly (1). The drill rod assembly (1) has a positioning ring (12) installed on the inner wall of the annular groove, and there is a gap between the positioning ring (12) and the annular groove. The upper and lower ends of the third reset elastic member (52) abut against the inner top of the annular groove (which can be marked in the attached drawing) and the top of the positioning ring (12), respectively. The inner wall of the piston body (51) is provided with a second flow channel (502), which constitutes the first section of the auxiliary flow channel (102), and the bottom end of the second flow channel (502) is engaged with the top end of the third flow channel (602) when the self-resetting impact piston (5) and the self-resetting impact piston (6) come into contact.

9. The rock breaking drill bit for oil extraction according to claim 8, characterized in that: The threshold valve assembly (7) includes a valve core (71), a fourth reset elastic element (72), and a valve seat (73); The valve core (71) is slidably connected to the top of the piston body (51) along the axial direction, and forms a closed control cavity (503) between the valve core (71) and the piston body (51). The upper and lower ends of the fourth reset elastic member (72) are respectively connected to the bottom of the valve core (71) and the inner bottom of the control cavity (503). A valve seat (73) is installed at the top of the second flow channel (502). The outer side wall of the valve seat (73) is provided with a side hole (701) that communicates with the second flow channel (502). The valve core (71) is movably sleeved on the outside of the valve seat (73) and separates the pressure chamber from the side hole (701). The side hole (701) communicates with the pressure chamber after the valve core (71) moves down.

10. The rock breaking drill bit for oil extraction according to claim 9, characterized in that: The secondary crushing assembly (9) includes an impact head (91), a piston rod (92), and a fifth reset elastic element (93). The impact head (91) is connected to the piston rod (92), and the piston rod (92) is adapted to the inner diameter of the first flow channel (204) to block the liquid outlet (202). The fifth reset elastic element (93) is sleeved on the outside of the impact head (91), and the two ends of the fifth reset elastic element (93) are respectively connected to the inner wall of the first flow channel (204) and the outer periphery of the connection end between the piston rod (92) and the impact head (91).

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