Anti-burying torque clutch of rotary guide drill rod and unfreezing method of anti-burying torque clutch

Abstract

The invention discloses an anti-burying torque clutch for a rotary guide drill rod and an unfreezing method of the anti-burying torque clutch. The anti-burying torque clutch comprises an upper connector and a lower connector, the upper end of the core tube is screwed in the inner screw hole in the lower end of the upper joint, the middle section is provided with an expanded core tube sealing section, and outer torque teeth are uniformly arranged on the circumference of the lower end; the upper end of the torque sleeve is sleeved on the periphery of the lower part of the upper joint, and the inner periphery of the lower part is provided with inner torque teeth meshed with the outer torque teeth; and the lower joint is screwed below the torque sleeve. The upper end of the hydraulic cylinder is mutually sealed, and the inner wall of the middle part of the hydraulic cylinder is mutually sealed with the sealing section of the core tube; the hydraulic cylinder shear pin locks the upper part of the hydraulic cylinder on the outer wall of the core tube; a hydraulic cavity is formed by the upper portion of the sealing section of the core pipe and the top of the hydraulic cylinder, and a pressure transmitting hole is formed in the core pipe and communicated with the hydraulic cavity. Torque teeth are separated by pressing down the drilling tool, building pressure and lifting up the drilling tool, so that the upper drilling tool can rotate freely, and the drilling tool is prevented from being buried; torque transmission can be achieved again, the lower rotary guiding instrument is driven to rotate, and jam releasing is achieved.

Description

Technical Field

[0001] The invention relates to a horizontal well drilling tool, in particular to a drill rod anti-buried torque clutch. The invention also relates to a method for releasing a rotary guide drill rod anti-buried torque clutch, belonging to the technical field of oil drilling. Background Art

[0002] Domestic deep shale oil and gas reservoirs are buried deep, generally ≥3500m. The target layer is generally drilled with a Ф215.9mm drill bit combined with a rotary steerable instrument. The rotary steerable drilling system has many advantages, which can effectively improve the mechanical drilling speed, control the wellbore trajectory in real time, improve the wellbore quality, and reduce the overall drilling cost. However, the instrument itself has a large outer diameter and strong rigidity, and the probability of the rotary steerable instrument being stuck due to formation block drop is high. The formations of my country's deep shale oil and gas wells are complex, and there are many complex underground conditions, which pose severe challenges to exploration and development. In the process of horizontal well drilling of shale gas in the Longmaxi Formation in southern Sichuan, there are complex drilling conditions such as wellbore instability, serious block drop, and frequent blockage. From 2019 to 2021, CNPC and Sinopec have buried 59 sets of rotary steerable instruments in the process of drilling shale gas wells in southern Sichuan, with a burial rate of up to 9.75%. The rotary steerable instrument is a high-precision technology product with extremely high cost. If it is buried, the loss will be great. In the complex wells with rotary steering for buried wells, the stuck drill accident occurred at the rotary steering position of the horizontal section (outer diameter 212mm), mainly due to the shale falling off and the stuck drill. After the rotary steering of many shale gas horizontal wells stuck the drill, except that the drill tool could not move freely, the drilling fluid circulation displacement was normal and the pump pressure was normal. Once the rotary steering instrument stuck the drill and buried the well, the loss was huge.

[0003] At present, shale dissolving agents have been developed on site to destroy the structural strength of shale according to the characteristics of the formation lithology components. However, after the rotary steerable instrument is stuck, it generally takes 3 to 4 days from organizing the unblocking agent or shale corrosive agent, to the unblocking agent or shale corrosive agent entering the well, and dissolving the blocks. During this period, the drill bit cannot be moved freely or rotated. During the circulation of the drilling fluid, the solid phase in the drilling fluid above the stuck point in the horizontal section gradually deposits on the lower well wall, or the drill bit circulates for a long time in a static state. The wellbore cuttings and small-sized blocks cannot be effectively returned under the stirring of the drill bit, resulting in most of them gradually spreading and accumulating between the drill pipe and the lower well wall, causing the lower side of the drill pipe in the horizontal well section to be gradually buried, causing more drill bits to be stuck, and increasing the difficulty of subsequent unblocking.

[0004] In the process of exploration and development of unconventional shale oil and gas wells, horizontal well sections often use near-bit while-drilling monitoring of formation gamma values ​​to ensure that the maximum amount of high-quality carbonaceous shale is obtained by rotary drilling in a directional manner, in order to maximize engineering, geological and economic benefits. Take the drilling of unconventional shale oil and gas horizontal well sections in the Sichuan Basin as an example: the Longmaxi Formation is mainly composed of non-expanding clay, and the hydration expansion and dispersion capabilities of the formation are poor, but it contains illite-montmorillonite mixed layers, which are highly water-sensitive and easily cause wellbore collapse and instability. The shale bedding and microcracks are developed, providing a natural channel for the invasion of drilling fluid filtrate. The filtrate invades the shale to hydrate the surface, and the hydration film "wedges" to connect the microcracks to the main fracture. Finally, the formation is mechanically damaged along the weakest point, causing wellbore instability such as block drop.

[0005] The Longmaxi Formation has the characteristics of dual wetting, with an oil wetting angle of 37.8°. When using oil-based drilling fluid, the invasion of oil phase filtrate is likely to cause adsorption, dissolution, swelling and other effects between the oil phase and organic matter. Different types of organic matter have different dissolution and swelling characteristics, and the resulting swelling pressure or solvation repulsion is different, causing stress imbalance inside the formation, which can easily cause the formation to peel off or collapse along the bedding and fracture sections. At the same time, the shale lamination and fractures of the Longmaxi Formation-Wufeng Formation are very developed, horizontal bedding fractures and high-angle structural fractures are generally developed, and multiple fractures and small faults are locally developed in the "ant body" structure. Among them, the organic-rich black shale in the Longyi 1 sub-member is the main target layer "geological sweet spot" for shale gas development. The study of its sub-layers shows that the clay content of Longyi 14 is high, the lamination of Longyi 13 is well developed, the pyrite stratification distribution of Longyi 12 and Longyi 11 is high, the brittleness index is high, and the continuous Class I reservoir is dominant. When drilling to the horizontal section, it is very easy to get stuck in the downhole failure of the rotary guide instrument combination. Combining the imaging logging data and the element analysis results of the block returned from multiple wells, it is found that the blocks are mostly from the interface between the shell limestone of Guanyinqiao Formation and the siliceous mudstone of Wufeng Formation at the bottom of Longyi 11. During the actual drilling process, under the condition of normal circulation of drilling fluid, the unstable shale formation peels off or the "ant body" formation suddenly collapses, and the top drive phenomenon stops instantly (the general limit of top drive is 25-30kN.m), resulting in the stuck drill of the rotary guide instrument combination.

[0006] The density of oil-based drilling fluid in deep and ultra-deep shale gas wells is high, generally exceeding 1.70g / cm³, averaging 2.10 g / cm³, and reaching a maximum of 2.87g / cm³. Ultrafine barite powder, ultrafine iron ore powder, and ultrafine manganese ore powder (MicroMax) are important materials for regulating the suspension stability and rheology of ultra-high density drilling fluids. Iron ore powder has a certain degree of magnetism, which will affect the use of measurement while drilling tools. Ultrafine manganese ore powder can effectively reduce the friction resistance between particles and significantly improve the rheology of drilling fluids, but its price is more than ten times that of high-density barite. Therefore, most oil-based drilling fluids are weighted with ultrafine barite powder, resulting in a solid content of more than 55% in the drilling fluid. After the rotary steerable (including drill bit) tool combination gets stuck, the drill bit cannot rotate, and the solid phase in the high-density oil-based drilling fluid gradually settles on the wellbore wall below the wellbore, causing barite powder to deposit and causing sticking on the lower side of the horizontal drill pipe. When handling the stuck drill, the upward pulling force and downward pressure cannot reach the stuck rotary steerable combination, causing the accident to worsen, resulting in the failure of the rotary steerable combination salvage and huge well burial losses.

[0007] After the rotary guide assembly is stuck, the following methods are generally used to try to release the stuck drill bit: ① lifting and lowering a large tonnage drill bit; ② twisting the drill bit with high torque; ③ jarring the drill bit up and down with a downhole jar, but the drill bit is unable to continuously rotate the drill bit (drill pipe) above the rotary guide assembly. According to the principles of fluid mechanics, the theoretical flow rate of the wellbore treatment is 0. Under the action of gravity, the solid particles move toward the bottom of the wellbore. As the stuck drill bit time increases, the solid phase in the high-density oil-based drilling fluid gradually settles more and more on the wellbore wall below the wellbore, aggravating the buried thickness and length of the solid phase in the lower half of the horizontal drill pipe, resulting in the failure of the jar, the pulling force of the large hook to lift up, and the pressure of the lower hook to lower down, which cannot be applied to the stuck rotary guide assembly part, making it more difficult to release the rotary guide assembly, resulting in the failure of the release.

[0008] The Chinese invention patent with publication number CN106150393B discloses a rotatable drill string sliding drilling short section, including a drilling fluid displacement control switch assembly and a transmission shaft assembly; the drilling fluid displacement control switch assembly includes an outer cylinder, an inner cylinder, a roller, a switch slider, a first spring, a second spring and a drilling fluid baffle structure; the transmission shaft assembly includes an inner hollow shaft; the upper end of the inner hollow shaft is inserted into the inner cavity of the inner cylinder and is connected to the lower end of the inner wall of the inner cylinder, and can rotate with the inner cylinder.

[0009] The Chinese invention patent with the publication number CN109750989B discloses a rotatable drill string directional drilling short section and a drilling method, including a housing; a cylinder body arranged in the cylinder housing; a switch assembly, the switch assembly is configured to separate the cylinder body and the housing when turned on so that they can rotate relative to each other, and to connect the cylinder body and the housing when turned off so that they can rotate synchronously; a well wall friction mechanism, including a first joint connected to the cylinder body, and a movable member arranged in the first joint, the movable member is configured to be able to move radially according to the displacement of the drilling fluid flowing through the short section, so as to selectively apply different friction forces to the well wall. During directional drilling, the switch is turned on, the drill pipe can rotate under the drive of the turntable, the counter torque of the screw drill tool below the short section is balanced by the friction force generated by the well wall friction mechanism, the tool face is in a stable state, and the effect of the rotatable drill string for directional drilling is achieved, thereby effectively reducing the support pressure effect and improving the mechanical drilling speed.

[0010] The above two invention patents have the following shortcomings: the start and stop of drill string rotation is controlled by displacement. On the one hand, the displacement cannot be accurately controlled during on-site construction, and the compression force generated by the displacement on the spring is also affected by multiple factors such as drilling fluid density and solid content, and the spring compression cannot be effectively controlled. On the other hand, when the drill bit is stuck, it will be unable to circulate due to the accumulation of rock cuttings, so this structure has great limitations in solving the problem of unblocking the drill bit. Summary of the invention

[0011] The primary purpose of the present invention is to overcome the problems existing in the prior art and provide a drill pipe anti-buried torque clutch that can transmit torque and pulling force downward and can also disconnect torque transmission. When it gets stuck below, it can be reliably unstuck and can maintain the independent rotation of the upper drill bit while maintaining the sealing of the pipe column.

[0012] In order to solve the above technical problems, a drill pipe anti-buried torque clutch of the present invention comprises: Upper joint, the upper port is connected to the upper pipe column; The core tube has an upper end screwed into the inner screw hole at the lower end of the upper joint, a core tube sealing section with an expanded diameter is provided in the middle section, and external torque teeth are evenly provided on the circumference of the lower end; A torque sleeve, the upper end of which is sleeved on the lower outer periphery of the upper joint, and the lower inner periphery is provided with inner torque teeth meshing with the outer torque teeth; The lower joint is screwed under the torque sleeve.

[0013] As an improvement of the present invention, the drill rod anti-buried torque clutch also includes: A liquid cylinder is sleeved on the outer periphery of the core tube and the upper ends are sealed with each other, and the inner wall of the middle part is sealed with the sealing section of the core tube; Cylinder shear pins lock the upper portion of the cylinder to the outer wall of the core tube; The upper part of the sealing section of the core tube and the top of the hydraulic cylinder form a hydraulic chamber, and the core tube is provided with a pressure transmission hole which communicates with the hydraulic chamber.

[0014] As a further improvement of the present invention, an elastic sleeve is mounted on the outer periphery of the liquid cylinder, and the top cover of the elastic sleeve covers the top of the liquid cylinder. A plurality of slots with lower ends opening are evenly arranged on the lower circumference of the elastic sleeve, and elastic claws with lower ends protruding toward the outer periphery are arranged between adjacent slots. Each elastic claw is embedded in a claw groove on the inner periphery of the lower part of the torque sleeve, and the claw groove is located above the inner torque tooth.

[0015] As a further improvement of the present invention, the lower end of the claw embedding groove is a horizontal right-angled side, and the upper end is provided with a chamfer.

[0016] As a further improvement of the present invention, the top of each elastic claw is provided with a claw upper conical surface which is narrow at the top and wide at the bottom, and each claw upper conical surface fits with the chamfer of the claw embedding groove.

[0017] As a further improvement of the present invention, the bottom of each elastic claw is provided with a claw lower conical surface which is narrow at the top and wide at the bottom. Each claw lower conical surface abuts against the core tube outer conical surface at the lower end of the core tube to lock each elastic claw in the claw groove of the torque sleeve. The core tube outer conical surface is located above the external torque tooth.

[0018] As a further improvement of the present invention, a bearing is installed below the inner step of the middle section of the torque sleeve, the lower end of the outer ring of the bearing abuts against the hole retaining ring, the hole retaining ring is embedded in the retaining ring groove of the inner wall of the torque sleeve, and the inner ring of the bearing is sleeved on the middle and lower outer periphery of the elastic sleeve, so that the elastic sleeve can rotate relative to the torque sleeve.

[0019] As a further improvement of the present invention, a ball seat support sleeve is provided below the core tube, and a support sleeve convex ring folded outward is provided at the upper end of the ball seat support sleeve, and the outer edge of the support sleeve convex ring is pressed between the torque sleeve and the lower joint, and a ball seat body for sealing the pressure ball is installed in the ball seat support sleeve.

[0020] As a further improvement of the present invention, the outer periphery of the upper large diameter section of the ball seat body is fixed to the inner wall of the ball seat support sleeve by ball seat shear nails, and the middle circumferential wall of the ball seat support sleeve 7 is evenly distributed with flow holes.

[0021] As a further improvement of the present invention, a ball seat sealing ring is embedded in the outer periphery of the large diameter section at the upper end of the ball seat body to achieve sealing with the inner wall of the ball seat support sleeve.

[0022] As a further improvement of the present invention, the lower end of the ball seat support sleeve is provided with a support sleeve inner step with a reduced diameter, and the lower end of the ball seat body passes through the center hole of the support sleeve inner step.

[0023] As a further improvement of the present invention, an axial gap is provided between the lower end of the core tube and the top of the ball seat support sleeve.

[0024] As a further improvement of the present invention, during normal drilling, the torque from the upper pipe string is transmitted to the core pipe through the upper joint, and the outer torque teeth at the lower end of the core pipe transmit the torque to the inner torque teeth of the torque sleeve, and then transmit it downward through the lower joint.

[0025] As a further improvement of the present invention, when drilling, the pulling force from the upper pipe string is transmitted to the core pipe through the upper joint, then transmitted to the elastic claw through the outer cone surface of the core pipe, and then transmitted from the elastic claw to the torque sleeve, and then transmitted downward by the torque sleeve through the lower joint.

[0026] Another object of the present invention is to overcome the problems existing in the prior art and provide a method for unjamming a drill pipe anti-buried torque clutch, which can reliably unjam when the clutch is stuck, thereby improving the unjamming success rate of the rotary guide instrument combination and providing a feasible solution for unjamming the rotary guide instrument in complex shale oil and gas wells with many falling blocks.

[0027] In order to solve the above technical problems, a method for releasing a rotary guide drill rod anti-buried torque clutch of the present invention comprises the following steps: S1. Put the pressure ball into the pipe string from the ground, and the pressure ball falls into the bell mouth of the ball seat to achieve sealing; S2, press down the drill tool to make the axial gap between the core tube and the ball seat support sleeve disappear, and the outer cone surface of the core tube at the lower end of the core tube is separated from the lower cone surface of the claw at the lower end of each elastic claw, so that each elastic claw has recovery space in the radial direction; S3. Turn on the pump and hold the pressure to 8-10MPa to cut off the hydraulic cylinder shear pins. The pressure liquid enters the hydraulic chamber of the hydraulic cylinder through the pressure transmission hole. Under the action of pressure, the hydraulic cylinder moves upward against the elastic sleeve. The elastic claws at the lower end are recovered and separated from the claw grooves of the torque sleeve. When the elastic claws are against the lower inner ring of the bearing, the elastic sleeve reaches the top dead center. S4, continue to hold the pressure to 15-17 MPa to cut off the ball seat shear nails, the ball seat body falls to the step inside the support sleeve at the lower end of the ball seat support sleeve, the flow hole is opened, and the circulation channel is established; S5, injecting a de-stuck agent from the wellhead, circulating the de-stuck agent to the stuck point of the drill string annulus through the flow hole to soak and dissolve the fallen blocks until the set soaking time is reached; S6. Press down the drill bit to re-engage the outer torque teeth at the lower end of the core tube with the inner torque teeth of the torque sleeve, and then rotate the drill bit to drive the rotary guide instrument and drill bit below to rotate to achieve jam release; while rotating the drill bit, perform a large displacement circulation to circulate the dropped blocks out of the wellhead to prevent them from accumulating again above the rotary guide instrument.

[0028] As an improvement of the present invention, in step S5, the pipe column is kept lifted during immersion so that the outer torque teeth at the lower end of the core pipe are disengaged from the inner torque teeth of the torque sleeve, and the drill bit is rotated from the ground to prevent the upper drill bit from being buried due to solid phase deposition of drilling fluid; the elastic claws and the inner ring of the bearing rotate with the upper drill bit to reduce rotational friction.

[0029] Compared with the prior art, the present invention has achieved the following beneficial effects: 1. When the clutch of the present invention is connected, the pulling force is transmitted from the core tube to the torque sleeve through the elastic claws. Since the elastic claws are subjected to shearing rather than stretching, the overall tensile strength is higher; after the clutch is disconnected, the upper drilling tool can rotate freely, but still has a strong tensile strength, ensuring that the lifting and lowering are unblocked, and the rotary guide instrument can be smoothly lifted to the wellhead.

[0030] 2. The present invention has high reliability. During normal drilling, the shearing nail mechanism is always kept free of stress, preventing the risk of premature shearing due to fatigue of the shear nails. The ball seat adopts an anti-drop design. After the shear nail shearing cycle is established, the pressure-holding ball and the ball seat body will not fall like the traditional ball seat, causing the risk of blocking the water eye. The present invention not only realizes the circulation flow, but also prevents the water eye from being blocked by falling.

[0031] 3. The present invention sets a drill pipe anti-buried torque clutch at a reasonable position in the drilling string. When the lower rotary guide instrument is stuck, the torque teeth are disengaged by pressing down the drill tool, holding the pressure, and lifting the drill tool, so that the upper drill tool can rotate freely. When the drilling fluid circulates, the deposited solid phase is driven to participate in the circulation, preventing the upper drill tool from being buried due to the deposition of the drilling fluid solid phase. After pressing down, the torque clutch can realize torque transmission again, drive the lower rotary guide instrument and the drill bit to rotate, and achieve unblocking.

[0032] 4. Wait for the unstuck fluid to dissolve the shale between the rotary guide instrument and the well wall, press down and rotate the drill bit, the torque teeth of the drill pipe anti-buried clutch will re-engage, drive the rotary guide instrument and the drill bit to rotate and unblock, thereby protecting the rotary guide instrument from being smoothly lifted to the wellhead, reducing the risk of being buried and reducing the cost of well construction.

[0033] 5. It is used for the rotary steering combination to get stuck in formations with well-developed microcracks, crisscrossed horizontal bedding fractures and high-angle structural fractures, and in "ant body" formations with many local fractures and small faults and many block formations. By reasonably designing the drilling string in advance, the drill pipe anti-buried torque clutch is set above the rotary steering instrument or above the predicted resistance point. After the drill is stuck, the torque transmission between the upper drill bit and the lower stuck rotary steering instrument is released through the drill bit anti-buried clutch joint, but the string is still kept sealed, so that the drill bit above the resistance point can rotate freely.

[0034] 6. During the circulation of drilling fluid, the drill bit above the stuck point can keep rotating all the time, driving the solid phase deposition of drilling fluid in the horizontal section to participate in the circulation with the drilling fluid, preventing the upper drill bit from being buried by the deposited solid phase and causing sticking or drilling burial, thereby improving the success rate of the rotary guide instrument combination for unstuck, and providing a feasible solution for the rotary guide instrument for drilling complex shale oil and gas wells with many broken blocks. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. The accompanying drawings are only provided for reference and explanation and are not intended to limit the present invention.

[0036] Figure 1 It is a front view of the drill rod anti-buried torque clutch of the present invention; Figure 2 A half-section view of the torque sleeve of the present invention; Figure 3 is a three-dimensional diagram of the core tube of the present invention; Figure 4 is a three-dimensional diagram of the elastic sleeve of the present invention; Figure 5 is a three-dimensional diagram of the upper joint in the present invention; In the figure: 1. upper joint; 1a. tapered female thread; 1b. smooth tube section; 2. torque sleeve; 2a. internal torque teeth; 3. core tube; 3a. core tube shear pin countersunk hole; 3b. pressure transmission hole; 3c. core tube sealing section; 3d. core tube outer cone; 3e. external torque teeth; 3f. core tube sealing ring; 4. elastic sleeve; 4a. elastic claw; 4b. upper cone surface of claw; 4c. lower cone surface of claw; 5. hydraulic cylinder; 5a. hydraulic cylinder sealing ring; 5b. hydraulic cylinder shear pin; 6. bearing; 6a. retaining ring for hole; 7. ball seat support sleeve; 7a. flow hole; 7b. inner step of support sleeve; 8. pressure holding ball; 9. ball seat body; 9a. ball seat sealing ring; 9b. ball seat shear pin; 10. lower joint. DETAILED DESCRIPTION

[0037] In the following description of the present invention, the terms "upper", "lower", "front", "back", "left", "right", "inner", "outer", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not mean that the device must have a specific orientation. Regardless of the state of the tool, the one closer to the ground is collectively referred to as "upper", and the one closer to the bottom of the well is collectively referred to as "lower".

[0038] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below with reference to specific diagrams.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0040] like Figures 1 to 5 As shown, the drill pipe anti-buried torque clutch of the present invention comprises an upper joint 1, a torque sleeve 2, a core tube 3, an elastic sleeve 4, a hydraulic cylinder 5, a bearing 6, a ball seat support sleeve 7, a pressure-holding ball 8, a ball seat body 9 and a lower joint 10. The upper end of the upper joint 1 is provided with a tapered female thread 1a for screwing with an upper pipe column or a tool, the inner screw hole at the lower end of the upper joint 1 is connected to the upper end of the core tube 3 through a sealing thread, the outer periphery of the core tube 3 is sleeved with a hydraulic cylinder 5, and is connected to the upper closed end of the hydraulic cylinder 5 through a hydraulic cylinder shear nail 5b, four hydraulic cylinder shear nails 5b are evenly screwed in the screw holes on the upper circumference of the hydraulic cylinder 5, the inner ends of each hydraulic cylinder shear nail 5b are respectively embedded in the core tube shear nail countersunk holes 3a on the outer periphery of the core tube 3 to fix the hydraulic cylinder 5, and the number of hydraulic cylinder shear nails 5b can also be adjusted by the shear value.

[0041] The upper closed end of the liquid cylinder 5 is embedded with a liquid cylinder sealing ring 5a to achieve sealing with the outer periphery of the core tube 3. The middle section of the core tube 3 is provided with a core tube sealing section 3c with an expanded diameter, and the outer periphery of the core tube sealing section 3c is embedded with a core tube sealing ring 3f to achieve sealing with the inner wall of the middle section of the liquid cylinder 5. A hydraulic chamber is formed between the upper part of the core tube sealing section 3c and the top of the liquid cylinder 5, and the hydraulic chamber is communicated with the central channel of the core tube 3 through the pressure transmission hole 3b.

[0042] The outer periphery of the cylinder 5 is covered with an elastic sleeve 4, the top of the elastic sleeve 4 is closed and abuts against the outer wall of the core tube 3, a plurality of slots with lower ends open are evenly milled on the lower circumference of the elastic sleeve 4, and elastic claws 4a with lower ends protruding toward the outer periphery are arranged between adjacent slots, and each elastic claw 4a is embedded in a claw embedding groove on the inner periphery of the lower middle part of the torque sleeve 2. The lower end of the claw embedding groove is a horizontal right-angled side, and the upper end is provided with a chamfer, which not only limits the upper end of the elastic claw 4a, but also facilitates the elastic claw 4a to slide upward.

[0043] The top of each elastic claw 4a is milled with an upper conical surface 4b that is narrow at the top and wide at the bottom, and the upper conical surface 4b of the claw cooperates with the chamfer of the claw groove; the bottom of each elastic claw 4a is milled with a lower conical surface 4c that is narrow at the top and wide at the bottom, and the lower conical surface 4c of the claw rests on the outer conical surface 3d of the core tube at the lower end of the core tube 3, thereby locking each elastic claw 4a in the claw groove of the torque sleeve 2.

[0044] The upper end of the torque sleeve 2 is sleeved on the outer periphery of the light tube section 1b at the lower part of the upper joint 1 and can float axially. A bearing 6 is installed below the inner step in the middle part of the torque sleeve 2. The bottom of the outer ring of the bearing 6 abuts against the hole retaining ring 6a. The hole retaining ring 6a is embedded in the retaining ring groove on the inner wall of the torque sleeve 2. The inner ring of the bearing 6 is sleeved on the outer periphery of the middle and lower part of the elastic sleeve 4.

[0045] The inner circumferential wall below the claw groove of the torque sleeve 2 is milled with uniformly distributed internal torque teeth 2a, and the lower end of the core tube 3 is circumferentially milled with uniformly distributed external torque teeth 3e. The internal torque teeth 2a and the external torque teeth 3e mesh with each other to transmit torque.

[0046] The lower end of the torque sleeve 2 is connected to the upper end of the lower joint 10 through a sealing thread, and the lower end of the lower joint is provided with a tapered male thread that is screwed to the lower pipe column or tool.

[0047] The upper end of the ball seat support sleeve 7 is provided with a support sleeve convex ring folded outward, and the outer edge of the support sleeve convex ring is pressed between the torque sleeve 2 and the lower joint 10, that is, the top of the support sleeve convex ring is pressed below the circumference of the inner torque tooth 2a, and the bottom of the support sleeve convex ring is pressed on the upper port of the lower joint 10.

[0048] The inner cavity of the ball seat support sleeve 7 is equipped with a ball seat body 9, and a ball seat sealing ring 9a is embedded in the outer circumference of the upper large diameter section of the ball seat body 9 and fixed to the inner wall of the ball seat support sleeve 7 by ball seat shear nails 9b, so that the ball seat sealing ring 9a is sealed with the inner wall of the ball seat support sleeve 7. The middle circumferential wall of the ball seat support sleeve 7 is evenly distributed with flow holes 7a to communicate the inner and outer spaces of the ball seat support sleeve 7.

[0049] The lower end of the ball seat support sleeve 7 is provided with a support sleeve inner step 7b with a reduced diameter, and the lower end of the ball seat body 9 passes through the central hole of the support sleeve inner step 7b and is clearance-matched with each other.

[0050] There are six ball seat shear nails 9b evenly screwed on the circumference of the ball seat support sleeve 7, and the number can also be adjusted by the shear value.

[0051] A gap is provided between the lower end surface of the core tube 3 and the top of the ball seat support sleeve 7, and the axial distance is greater than 10 mm.

[0052] The pressure holding ball 8 can be made of copper alloy, and the external vulcanized rubber improves the sealing reliability. It does not enter the well synchronously with the pipe string. When the rotary guide instrument is stuck and the torque clutch needs to work, it is put into the pipe string from the ground.

[0053] The pipe string from bottom to top is composed of drill bit, rotary guide instrument, drill pipe anti-buried torque clutch, and drill tool. The upper part of the drill tool is directly connected to the drilling rig. When the drill string rotates and drills, the rotary guide instrument completes the geological guidance function in real time. Its outer diameter is Ф212mm, which is larger than the outer diameter of the drill tool Ф165mm. The drill tool is made of multiple drill pipes connected one by one through a coupling. It transports drilling mud to the drill bit, and together with the drill bit, it raises, lowers or rotates the bottom hole device and extends the length of the wellbore.

[0054] The upper part of the drill pipe is directly connected to the top drive of the drilling rig to provide the torque and drilling fluid circulation required during the drilling process. Among them, the outer diameter of the drill bit> the outer diameter of the rotary guide instrument> the outer diameter of the drill pipe anti-buried clutch> the outer diameter of the drill pipe.

[0055] During normal drilling, the torque is transmitted through the upper joint 1, the core tube 3, the torque sleeve 2, and the lower joint 10. The bottom of the core tube 3 is pressed on the top of the ball seat support sleeve 7, and the two are in axial contact to transmit the drilling pressure. When pulling out of the hole, the pulling force is transmitted through the upper joint 1, the core tube 3, the elastic claw 4a, the torque sleeve 2, and the lower joint 10. At this time, there is an axial gap between the core tube 3 and the ball seat support sleeve 7.

[0056] When drilling in the actual horizontal section, shale blocks are very likely to get stuck at the rotary guide tool position with a larger outer diameter, that is, stuck between the rotary guide tool and the well wall. Lifting, lowering, and increasing torque can never unblock it. After a long period of circulation, the solid phase deposition of drilling fluid will gradually increase below the horizontal section drill bit, causing the drill bit position to also get stuck.

[0057] At this time, the pressure-holding ball 8 is thrown into the pipe column from the ground, and can fall freely, or the pump can be turned on to pump the pressure-holding ball 8. The pressure-holding ball 8 falls into the horn mouth at the upper end of the ball seat body 9 to realize the setting.

[0058] Then the drill bit is pressed down by 10 tons, and relative sliding occurs between the upper joint 1 and the torque sleeve 2. The axial clearance between the core tube 3 and the ball seat support sleeve 7 disappears, and the outer conical surface 3d of the core tube at the lower end of the core tube 3 sinks and disengages from the lower conical surface 4c of the claw at the lower end of each elastic claw 4a, so that each elastic claw 4a of the elastic sleeve 4 has recovery space in the radial direction.

[0059] The pump is turned on and the pressure is held up to 8-10 MPa, the hydraulic cylinder shear pin 5b is cut off, and the pressure fluid enters the hydraulic chamber of the hydraulic cylinder 5 through the pressure transmission hole 3b. The hydraulic cylinder 5 moves upward under the pressure, and the elastic sleeve 4 slides upward under the push of the hydraulic cylinder 5. The elastic claws 4a at the lower end are recovered and slide out of the claw grooves of the torque sleeve 2, and slide upward along the inner wall of the torque sleeve 2. When the elastic claws 4a at the lower end of the elastic sleeve 4 abut against the lower inner ring of the bearing 6, the rise is limited.

[0060] Continue to hold the pressure to 15-17 MPa, cut off the ball seat shear nail 9b, and the ball seat body 9 falls down. The inner step 7b of the support sleeve at the lower end of the ball seat support sleeve 7 sets a lower limit on the ball seat body 9. The pressure holding ball 8 and the ball seat body 9 will not fall down like the traditional ball seat, causing the risk of blocking the water eye. The present invention adopts a design of not separating after shearing off, which not only realizes the circulation flow, but also prevents the falling and blocking the water eye.

[0061] At this time, the flow hole 7a is opened to establish a circulation channel. The unstuck agent is injected from the wellhead, and the unstuck agent passes through the flow hole 7a downward from the drill bit water hole at the bottom of the well into the annular space outside the drill string, and then reaches the outer annulus of the rotary guide instrument upward to soak and unstuck, dissolving the shale blocks.

[0062] During the soaking period, the pipe column is lifted up to disengage the outer torque teeth 3e at the lower end of the core pipe 3 from the inner torque teeth 2a of the torque sleeve 2, and the drill tool is rotated from the ground to avoid the risk of the upper drill tool being buried due to the solid phase deposition of the drilling fluid during the circulation of the drilling fluid. During this process, the elastic claw 4a and the inner ring of the bearing 6 rotate with the upper drill tool to reduce the rotational friction and increase the overall service life.

[0063] After the unstuck liquid is soaked for a set time, the shale blocks have been dissolved. At this time, the drill bit is rotated after pressing down, so that the outer torque teeth 3e at the lower end of the core tube 3 re-engage with the inner torque teeth 2a of the torque sleeve 2, driving the rotary guide instrument and the drill bit below to rotate, and unstuck, thereby protecting the rotary guide instrument so that it can be smoothly brought to the wellhead, reducing the risk of being buried and reducing the cost of well construction. While rotating the drill bit, a large displacement cycle is performed to circulate the loose blocks out of the wellhead to prevent the blocks from accumulating again above the rotary guide instrument.

[0064] The above is only a preferred embodiment of the present invention, which shows and describes the basic principles, main features and advantages of the present invention, but does not limit the scope of patent protection of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. In addition to the above embodiments, the present invention may have other implementation modes without departing from the spirit and scope of the present invention. The present invention may also have various changes and improvements, and all technical solutions formed by equivalent substitution or equivalent transformation fall within the scope of protection required by the present invention. The scope of protection required by the present invention is defined by the attached claims and their equivalents. The technical features not described in the present invention can be realized by or using existing technologies, which will not be repeated here.

Claims

1. A drill pipe anti-buried torque clutch, characterized in that: include: Upper joint, the upper port is connected to the upper pipe column; The core tube has an upper end screwed into the inner screw hole at the lower end of the upper joint, a core tube sealing section with an expanded diameter is provided in the middle section, and external torque teeth are evenly provided on the circumference of the lower end; A torque sleeve, the upper end of which is sleeved on the lower outer periphery of the upper joint, and the lower inner periphery is provided with inner torque teeth meshing with the outer torque teeth; The lower joint is screwed under the torque sleeve.

2. The drill pipe anti-buried torque clutch according to claim 1, characterized in that: Also includes: A liquid cylinder is sleeved on the outer periphery of the core tube and the upper ends are sealed with each other, and the inner wall of the middle part is sealed with the sealing section of the core tube; Cylinder shear pins lock the upper portion of the cylinder to the outer wall of the core tube; The upper part of the sealing section of the core tube and the top of the hydraulic cylinder form a hydraulic chamber, and the core tube is provided with a pressure transmission hole which communicates with the hydraulic chamber.

3. The drill pipe anti-buried torque clutch according to claim 2, characterized in that: An elastic sleeve is sleeved on the outer circumference of the liquid cylinder, and the top cover of the elastic sleeve covers the top of the liquid cylinder. A plurality of slots with lower ends opening are evenly arranged on the lower circumference of the elastic sleeve, and elastic claws with lower ends protruding toward the outer circumference are arranged between adjacent slots. Each elastic claw is embedded in a claw embedding groove on the inner circumference of the lower part of the torque sleeve, and the claw embedding groove is located above the inner torque tooth.

4. The drill pipe anti-buried torque clutch according to claim 3, characterized in that: The lower end of the claw embedding groove is a horizontal right-angled side, and the upper end is provided with a chamfer.

5. The drill pipe anti-buried torque clutch according to claim 4, characterized in that: The top of each elastic claw is respectively provided with a claw upper conical surface which is narrow at the top and wide at the bottom, and each claw upper conical surface fits with the chamfer of the claw embedding groove.

6. The drill pipe anti-buried torque clutch according to claim 5, characterized in that: The bottom of each elastic claw is provided with a claw lower conical surface which is narrow at the top and wide at the bottom. Each claw lower conical surface abuts against the core tube outer conical surface at the lower end of the core tube to lock each elastic claw in the claw groove of the torque sleeve. The core tube outer conical surface is located above the external torque tooth.

7. The drill pipe anti-buried torque clutch according to claim 3, characterized in that: A bearing is installed below the inner step of the middle section of the torque sleeve, the lower end of the outer ring of the bearing abuts against the hole retaining ring, the hole retaining ring is embedded in the retaining ring groove of the inner wall of the torque sleeve, and the inner ring of the bearing is sleeved on the middle and lower outer periphery of the elastic sleeve, so that the elastic sleeve can rotate relative to the torque sleeve.

8. The drill pipe anti-buried torque clutch according to claim 3, characterized in that: A ball seat support sleeve is provided below the core tube, and a support sleeve convex ring folded outward is provided at the upper end of the ball seat support sleeve. The outer edge of the support sleeve convex ring is pressed between the torque sleeve and the lower joint, and a ball seat body for sealing the pressure-holding ball is installed in the ball seat support sleeve.

9. The drill pipe anti-buried torque clutch according to claim 8, characterized in that: The outer periphery of the upper large diameter section of the ball seat body is fixed to the inner wall of the ball seat support sleeve by ball seat shear nails, and the middle circumferential wall of the ball seat support sleeve 7 is evenly distributed with flow holes.

10. The drill pipe anti-buried torque clutch according to claim 8, characterized in that: A ball seat sealing ring is embedded on the outer periphery of the large diameter section at the upper end of the ball seat body to achieve sealing with the inner wall of the ball seat support sleeve.

11. The drill pipe anti-buried torque clutch according to claim 8, characterized in that: The lower end of the ball seat support sleeve is provided with a support sleeve inner step with a reduced diameter, and the lower end of the ball seat body passes through the central hole of the support sleeve inner step.

12. The drill pipe anti-buried torque clutch according to claim 8, characterized in that: An axial gap is provided between the lower end of the core tube and the top of the ball seat support sleeve.

13. The drill pipe anti-buried torque clutch according to claim 12, characterized in that: During normal drilling, the torque from the upper pipe string is transmitted to the core pipe through the upper joint, and the outer torque teeth at the lower end of the core pipe transmit the torque to the inner torque teeth of the torque sleeve, and then transmit it downward through the lower joint.

14. The drill pipe anti-buried torque clutch according to claim 12, characterized in that: When drilling, the pulling force from the upper pipe string is transmitted to the core pipe through the upper joint, then transmitted to the elastic claw through the outer cone surface of the core pipe, and then transmitted from the elastic claw to the torque sleeve, and then transmitted downward by the torque sleeve through the lower joint.

15. A method for releasing the anti-buried torque clutch of a rotary guide drill rod as claimed in claim 12, characterized in that: The steps include: S1. Put the pressure ball into the pipe string from the ground, and the pressure ball falls into the bell mouth of the ball seat to achieve sealing; S2, press down the drill tool to make the axial gap between the core tube and the ball seat support sleeve disappear, and the outer cone surface of the core tube at the lower end of the core tube is separated from the lower cone surface of the claw at the lower end of each elastic claw, so that each elastic claw has recovery space in the radial direction; S3. Turn on the pump and hold the pressure to 8-10MPa to cut off the hydraulic cylinder shear pins. The pressure liquid enters the hydraulic chamber of the hydraulic cylinder through the pressure transmission hole. Under the action of pressure, the hydraulic cylinder moves upward against the elastic sleeve. The elastic claws at the lower end are recovered and separated from the claw grooves of the torque sleeve. When the elastic claws are against the lower inner ring of the bearing, the elastic sleeve reaches the top dead center. S4, continue to hold the pressure to 15-17 MPa to cut off the ball seat shear nails, the ball seat body falls to the step inside the support sleeve at the lower end of the ball seat support sleeve, the flow hole is opened, and the circulation channel is established; S5, injecting a de-stuck agent from the wellhead, circulating the de-stuck agent to the stuck point of the drill string annulus through the flow hole to soak and dissolve the fallen blocks until the set soaking time is reached; S6. Press down the drill bit to re-engage the outer torque teeth at the lower end of the core tube with the inner torque teeth of the torque sleeve, and then rotate the drill bit to drive the rotary guide instrument and drill bit below to rotate to achieve jam release; while rotating the drill bit, perform a large displacement circulation to circulate the dropped blocks out of the wellhead to prevent them from accumulating again above the rotary guide instrument.

16. The method for releasing the drill pipe anti-buried torque clutch according to claim 15, characterized in that: In step S5, the pipe column is lifted up during the soaking period, so that the outer torque teeth at the lower end of the core pipe are disengaged from the inner torque teeth of the torque sleeve, and the drill bit is rotated from the ground to prevent the upper drill bit from being buried due to the solid phase deposition of the drilling fluid; the elastic claws and the inner ring of the bearing rotate with the upper drill bit to reduce the rotational friction.

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