Hydraulic device for freeing stuck drill rig

Abstract

The application discloses a hydraulic device for releasing a stuck drill rod, and belongs to the technical field of mine drilling, which comprises a base, a nozzle member and a liquid supply device. The base is movably sleeved outside the drill rod. The nozzle member is arranged on the base and is provided with a first nozzle and a second nozzle. The first nozzle and the second nozzle are both connected with the liquid supply device. The first nozzle is arranged towards the bottom wall of the drill hole. The second nozzle is arranged towards the side wall of the drill hole. The second nozzle is arranged at an angle with the first nozzle. The second nozzle is used for spraying liquid to the side wall of the drill hole to drive the base to move towards the bottom wall of the drill hole. The application can reduce the damage of the drill rod during the releasing process.

Description

Technical Field

[0001] This invention belongs to the field of mining drilling technology, and more specifically relates to a hydraulic unblocking device for stuck drill bits. Background Technology

[0002] During downhole drilling operations, a stuck drill pipe or drill bit can become stuck and unable to rotate or move when it gets stuck in the borehole wall due to rock powder, soft plastic rock, or coal slag. Stuck drill pipe accidents can delay production progress and may even cause secondary disasters such as gas outbursts and water inrushes because critical boreholes cannot be completed.

[0003] Currently, the conventional methods for handling stuck drill bit accidents include: shock method and forceful pulling method. The shock method generally uses impact vibration to remove the encapsulated impurities, while the forceful pulling method generally uses strong pulling force to gradually lift the stuck drill bit away from the stuck point. However, shock and forceful pulling often require repeated attempts, have a low success rate, and are prone to damaging the drill pipe or even causing it to break, thus complicating the accident.

[0004] Therefore, how to provide a device that reduces drill pipe damage during the unblocking process is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of this, the present invention provides a hydraulic unblocking device for stuck drill bits, which can reduce damage to the drill rod during the unblocking process.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] Drill rig stuck with hydraulic ejection equipment, including:

[0008] A base for being movably fitted onto the outside of the drill pipe;

[0009] A jetting component is disposed on the base. The jetting component has a first nozzle and a second nozzle. Both the first nozzle and the second nozzle are used to communicate with a liquid supply device. The first nozzle is positioned towards the bottom wall of the borehole, and the second nozzle is positioned towards the side wall of the borehole. The second nozzle is positioned at an angle to the first nozzle, and the second nozzle is used to jet liquid onto the side wall of the borehole to drive the base to move toward the bottom wall of the borehole.

[0010] Optionally, at least two spray elements are provided, and each spray element is arranged at circumferential intervals along the base.

[0011] Optionally, the base is provided with a liquid storage chamber, which is used to communicate with the liquid supply device, and the first nozzle and the second nozzle of each of the spraying elements are both connected to the liquid storage chamber.

[0012] Optionally, the liquid storage chamber is connected to at least two liquid outlet pipes, and the liquid outlet pipes are detachably connected to the spraying elements one by one. The first nozzle and the second nozzle of each spraying element are connected to the corresponding liquid outlet pipe.

[0013] Optionally, the spray element is provided with a sealing element, and the spray element is sealed to the inner wall of the liquid outlet pipe through the sealing element.

[0014] Optionally, the liquid storage chamber is connected to at least one liquid inlet pipe, each of the liquid inlet pipes is used to connect to the liquid supply device, and each of the liquid inlet pipes may optionally be coaxially arranged and directly connected to one of the liquid outlet pipes.

[0015] Optionally, the spraying member is provided with at least two first nozzles, the first nozzles are distributed along the circumference of the spraying member, and each first nozzle is inclined relative to the axis of the spraying member, and the spraying direction of each first nozzle is different.

[0016] Optionally, the spraying member is provided with at least two second nozzles, which are distributed circumferentially along the spraying member, and each second nozzle is inclined relative to the axis of the spraying member, and the spraying direction of each second nozzle is different.

[0017] Optionally, the base is provided with a rolling assembly, which includes at least two rolling elements. The rolling elements are arranged at intervals along the circumference of the base, and each rolling element is movably disposed on the inner side of the base. The rolling elements are used to contact the drill rod.

[0018] Optionally, at least two rolling components are provided, and each rolling component is arranged sequentially along the axial direction of the base.

[0019] The above technical solution includes at least the following technical effects:

[0020] The first nozzle of the jetting component sprays water towards the bottom wall of the borehole, impacting and loosening stuck materials such as sediment and rock cuttings from the drill pipe. The second nozzle faces the side wall of the borehole and is set at an angle to the first nozzle. The water jet it sprays generates a reverse thrust, driving the base to move along the drill pipe towards the bottom wall of the borehole. This allows the jetting component to gradually approach the stuck area, further improving the unblocking efficiency. During the gradual movement, the water jet from the second nozzle can further disperse or even push out the loosened stuck material, improving the cleaning effect. During the cleaning process, the drill pipe is basically not subjected to additional mechanical impact or strong tension, thus effectively reducing the risk of drill pipe damage or breakage caused by strong operation. Attached Figure Description

[0021] 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 embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0022] Figure 1 This is a side view of the hydraulic unblocking device for a stuck drill bit in an embodiment of the present invention.

[0023] Figure 2 This is a front view of the hydraulic unblocking device for a stuck drill bit in an embodiment of the present invention.

[0024] Figure 3 This is a schematic diagram of the jetting component of the hydraulic unjamming device for a stuck drill bit in an embodiment of the present invention.

[0025] Explanation of reference numerals in the attached figures:

[0026] 1. Drill pipe; 2. Base; 21. Liquid storage chamber; 22. Liquid outlet pipe; 23. Liquid inlet pipe; 3. Injector; 31. First nozzle; 32. Second nozzle; 33. Seal; 4. Rolling assembly; 5. Rolling component. Detailed Implementation

[0027] The technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

[0028] The terms "first," "second," etc., used in the specification and claims of this invention are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0029] The hydraulic unblocking device for stuck drill bits provided in this invention will be described in detail below with reference to the accompanying drawings and through specific embodiments and application scenarios.

[0030] See appendix Figure 1-3This invention provides a hydraulic unblocking device for stuck drill bits, comprising:

[0031] The base 2 is used to be movably fitted onto the outside of the drill rod 1.

[0032] Optionally, the base 2 adopts a cylindrical structure, and the base 2 is available in various models with different inner diameters. When using it, the base 2 with different inner diameters can be selected according to the diameter of the drill rod 1.

[0033] The spraying element 3 is disposed on the base 2. The spraying element 3 is provided with a first nozzle 31 and a second nozzle 32. Both the first nozzle 31 and the second nozzle 32 are used to connect to the liquid supply device. The first nozzle 31 is set towards the bottom wall of the borehole, and the second nozzle 32 is set towards the side wall of the borehole. The second nozzle 32 is set at an angle to the first nozzle 31, and the second nozzle 32 is used to spray liquid onto the side wall of the borehole to drive the base 2 to move towards the bottom wall of the borehole.

[0034] Optionally, the liquid supply device adopts a high-pressure water supply system consisting of a high-pressure water pump and a high-pressure pipeline to supply high-pressure water flow to the first nozzle 31 and the second nozzle 32. The spray element 3 is made of hard alloy or high-strength ceramic material to resist the erosion of the high-pressure water flow.

[0035] The water jet ejected from the first nozzle 31 can impact sediment, rock cuttings, and other materials that cause the drill to get stuck, loosening the adhesion between these materials and the drill rod 1, removing the encapsulated material and breaking down obstacles.

[0036] The water jet ejected from the second nozzle 32 generates a reverse thrust, pushing the base 2 along the drill rod 1 toward the bottom wall of the borehole, allowing the jetting component 3 to gradually approach the stuck drill area, further improving the unblocking efficiency. In addition, the water jet ejected from the second nozzle 32 can further disperse or even push out the loosened stuck drill material, improving the cleaning effect and preventing secondary accumulation of the wrapped material.

[0037] In this embodiment, specifically, at least two spray elements 3 are provided, and each spray element 3 is arranged at intervals along the circumference of the base 2.

[0038] By setting multiple jetting elements 3, the stuck material in the borehole can be impacted and cleaned from different directions, improving the comprehensiveness and uniformity of the cleaning. At the same time, the driving force generated by the water jets from multiple second nozzles 32 is more balanced, which can effectively reduce the possibility of the base 2 tilting during movement.

[0039] In this embodiment, specifically, the base 2 is provided with a liquid storage chamber 21, which is used to connect with the liquid supply device, and the first nozzle 31 and the second nozzle 32 of each spray element 3 are connected to the liquid storage chamber 21.

[0040] The liquid storage chamber 21 can temporarily store and buffer the liquid supplied by the liquid supply device, ensuring that the first nozzle 31 and the second nozzle 32 of each spray element 3 can stably spray out liquid, avoiding the impact of liquid supply pressure fluctuations on the spraying effect.

[0041] Optionally, the inner wall of the liquid storage chamber 21 is specially smoothed to effectively reduce the resistance of the liquid flowing in the chamber, reduce the generation of turbulence, and further ensure the stability of the liquid output.

[0042] In this embodiment, specifically, the liquid storage chamber 21 is connected to at least two liquid outlet pipes 22, and the liquid outlet pipes 22 correspond one-to-one with the spraying elements 3 and are detachably connected. The first nozzle 31 and the second nozzle 32 of each spraying element 3 are connected to the corresponding liquid outlet pipe 22.

[0043] Optionally, the spray element 3 and the liquid outlet pipe 22 can be detachably fixed by threaded connection or bolt connection. This detachable connection method facilitates the installation, disassembly and replacement of the spray element 3. When a spray element 3 is damaged, or when different types of spray elements 3 need to be replaced according to different working requirements, it is only necessary to separate the corresponding liquid outlet pipe 22 from the spray element 3. The operation is simple and convenient.

[0044] Optionally, the end of the spray element 3 near the liquid outlet pipe 22 is a smooth cylindrical surface so as to fit tightly against the inner wall of the liquid outlet pipe 22. The size and quantity of the spray element 3 are selected according to the base 2 used.

[0045] In this embodiment, specifically, the spray element 3 is provided with a sealing element 33, and the spray element 3 is sealed to the inner wall of the liquid outlet pipe 22 through the sealing element 33.

[0046] Optionally, the sealing element 33 can be a high-pressure resistant rubber ring, which is fitted on the connection between the spray element 3 and the liquid outlet pipe 22. When the spray element 3 and the liquid outlet pipe 22 are assembled in place, the sealing element 33 is squeezed and undergoes elastic deformation, which can effectively prevent high-pressure liquid from leaking from the connection and ensure that all liquid is sprayed out from the first nozzle 31 and the second nozzle 32, thus ensuring the spray pressure and impact force.

[0047] In this embodiment, specifically, the liquid storage chamber 21 is connected to at least one liquid inlet pipe 23, each liquid inlet pipe 23 is used to connect to the liquid supply device, and each liquid inlet pipe 23 may be selectively coaxially arranged and directly connected to a liquid outlet pipe 22.

[0048] Compared to the liquid storage chamber 21 being directly connected to the liquid inlet pipe 23, when the liquid inlet pipe 23 and the liquid outlet pipe 22 are coaxially arranged and directly connected, the liquid does not need to pass through the buffer and deflection inside the liquid storage chamber 21 after entering from the liquid inlet pipe 23, but directly enters the liquid outlet pipe 22 in a straight line, thereby increasing the water jet impact force of the corresponding liquid outlet pipe 22.

[0049] Optionally, the liquid inlet pipe 23 and the liquid supply device are connected by a threaded connection. The threaded connection has good sealing and disassembly, which facilitates the installation, replacement and maintenance of the liquid supply device. At the same time, it can maintain a stable connection during long-term use and prevent the connection from loosening due to vibration or pressure changes.

[0050] Optionally, both the liquid outlet pipe 22 and the liquid inlet pipe 23 are integrally formed with the base 2. The integrally formed structural design significantly improves the structural strength and stability of the overall device, avoids the problem of breakage or deformation at the interface that may occur with traditional assembled pipes, extends the service life of the equipment, and reduces the later maintenance costs.

[0051] In this embodiment, specifically, the spraying member 3 is provided with at least two first nozzles 31, the first nozzles 31 are distributed along the circumference of the spraying member 3, and each first nozzle 31 is inclined relative to the axis of the spraying member 3, and the spraying direction of each first nozzle 31 is different.

[0052] The first nozzles 31 are distributed circumferentially on the jetting element 3, and the tilt angle of each first nozzle 31 is different. This allows the water jets ejected from the first nozzles 31 to cover a wider area and impact the stuck material at different positions on the bottom wall of the borehole, thereby enhancing the impact effect.

[0053] Furthermore, the number of first nozzles 31 can be set according to the actual borehole diameter and impact requirements to ensure the uniformity and comprehensiveness of the water jet impact. The included angle between adjacent first nozzles 31 is equal, so that the ejected water jet forms an annular impact area on the bottom wall of the borehole, avoiding the occurrence of impact dead zones.

[0054] Optionally, the angle of the jet stream from the first nozzle 31 relative to the axis of the jetting element 3 is 15°-30°. When the inclined jet stream impacts the rock surface, it not only generates impact pressure but also forms a strong shear force, which is more effective for breaking and stripping the rock mass.

[0055] Compared to the first nozzle 31's vertical forward impact, which may result in some energy rebounding with stuck drill bits and causing equipment damage, the inclined impact can use energy more fully for crushing and cutting, and give the stuck drill bits a force away from the drill rod 1, thereby reducing the possibility of damage to the drill rod 1 and the equipment.

[0056] In this embodiment, specifically, the spraying member 3 is provided with at least two second nozzles 32, the second nozzles 32 are distributed along the circumference of the spraying member 3, and each second nozzle 32 is inclined relative to the axis of the spraying member 3, and the spraying direction of each second nozzle 32 is different.

[0057] This design of the second nozzles 32, which are circumferentially distributed and have different directions, enables the fluid ejected from the second nozzles 32 to form a multi-angle, all-round spray coverage around the ejector 3, effectively enhancing the contact area and mixing effect between the fluid and the surrounding medium. When the fluid is ejected from the inclined second nozzles 32, it will generate a jet with a certain angle. The jets in different directions interact and collide in space, forming a complex flow field, thereby increasing the scouring force on the surrounding materials.

[0058] Optionally, the angle of the jet flow of the second nozzle 32 relative to the axis of the jetting element 3 is 15°-30°. When the second nozzle 32 sprays, the water jet will generate a reaction force on the second nozzle 32 itself. The axial component of this reaction force points in front of the drill pipe 1 and can be used as an active thrust to push the entire device forward. After the radial components of the reaction forces of all the second nozzles 32 on the same jetting element 3 cancel each other out, the remaining radial component acts on the base 2, so that the base 2 can fit more stably on the drill pipe 1.

[0059] Avoid spraying water from the nozzle completely vertically backward to prevent high-pressure water jets from flowing out of the borehole at high speed without buffering, which could injure workers and equipment.

[0060] Furthermore, in order to ensure that the second nozzle 32 provides sufficient thrust while avoiding excessive dispersion of the water jet, each second nozzle 32 should be evenly distributed in the circumferential direction of the spray member 3, and the included angle between two adjacent second nozzles 32 should be equal. This will enable the radial component of the reaction force to cancel each other out more evenly, reducing the possibility of shaking of the base 2 due to uneven force.

[0061] Optionally, it is necessary to ensure that the total flow rate of the second nozzle 32 is greater than the total flow rate of the first nozzle 31, so as to ensure that the thrust provided by the second nozzle 32 is sufficient to move the base 2. When the nozzle diameter is the same, the number of second nozzles 32 should be greater than the number of first nozzles 31. Preferably, there are 6 second nozzles 32 and 4 first nozzles 31.

[0062] In this embodiment, specifically, the base 2 is provided with a rolling assembly 4, which includes at least two rolling elements 5. Each rolling element 5 is arranged at intervals along the circumference of the base 2, and each rolling element 5 is movably disposed on the inner side of the base 2. The rolling element 5 is used to contact the drill rod 1.

[0063] Optionally, the rolling element 5 is made of balls. The inner wall of the base 2 is machined with an annular groove along the circumference. A ring of wear-resistant balls that can rotate freely is embedded in this annular groove. One end of the ball protruding from the inner wall surface contacts the outer wall of the drill rod 1. The balls can convert the sliding friction between the base 2 and the drill rod 1 into rolling friction, reduce the resistance when the base 2 moves on the drill rod 1, make the movement of the base 2 smoother, and thus achieve low-resistance sliding of the base 2, improve the smoothness of the movement of the base 2, and reduce the impact force requirement on the second nozzle 32.

[0064] Furthermore, the balls are made of high-hardness alloy material, and after precision machining, the surface is extremely smooth, which not only effectively improves wear resistance and extends the service life of the rolling assembly 4, but also minimizes the coefficient of friction when in contact with the outer wall of the drill rod 1.

[0065] In this embodiment, specifically, at least two rolling components 4 are provided, and each rolling component 4 is arranged sequentially along the axial direction of the base 2.

[0066] The multiple rolling components 4 can further improve the stability and guidance of the base 2 moving on the drill pipe 1, prevent the base 2 from shaking or shifting during movement, and ensure that the jetting component 3 can accurately target the stuck drill area for cleaning.

[0067] Optionally, such as Figure 1 As shown, a rolling component 4 is provided at both the front and rear ends of the base 2 to prevent the base 2 from shaking or tilting during movement.

[0068] This invention achieves the breaking function by using high-pressure water jet technology, without hard contact with the rock mass or encapsulated material in front. Compared with methods that use rapid rotation or impact to break stuck materials, this non-contact operation mode has higher safety and can effectively reduce the risk of damage or breakage of drill rod 1 due to strong operation.

[0069] Existing anti-jamming drill bits are generally manufactured with special structures, resulting in low versatility. They are primarily used as preventative measures to reduce the probability of drill bit jamming. However, once jamming does occur, anti-jamming drill bits not only struggle to self-unjam, but their special structures also increase the difficulty of unjamming.

[0070] Compared to existing technical solutions aimed at preventing stuck drill pipe, this invention focuses on resolving existing stuck drill pipe accidents. After a stuck drill pipe accident occurs, this invention can unblock the already formed stuck state by gradually cleaning the encapsulated material around the drill pipe 1 through the base 2 and the jetting component 3, resulting in a more thorough and reliable unblocking effect.

[0071] The crushing and cleaning functions of this invention are achieved using the kinetic energy of high-pressure water jets, greatly reducing the risk of sparks generated by metal friction or impact, making it suitable for hazardous environments with strict explosion-proof requirements, such as gas mines. Simultaneously, it reduces the risks of secondary damage to the drill pipe, tool breakage, or exacerbation of stuck drill bits that may occur with traditional mechanical crushing methods. Furthermore, as a clean energy source, high-pressure water jets produce no pollutants during operation, and the water medium itself has cooling and dust-suppressing properties, further improving the working environment.

[0072] This invention utilizes the reaction force generated by the jet from the rear nozzle to achieve self-propelled forward movement, eliminating the need for an additional propulsion mechanism. Throughout the unblocking process, the operator's main tasks are initial installation, connecting the high-pressure water pipe, starting the water pump, and monitoring pressure and water return. This greatly simplifies the on-site operation process. In situations with limited downhole space and complex environments, this simple and automated operation mode significantly improves the safety and convenience of the operation. Simultaneously, it helps reduce the personnel and working hours required for accident handling, lowering the technical requirements and labor intensity for operators.

[0073] The specific usage method is as follows:

[0074] According to the specifications of the stuck drill rod 1, select and install the appropriate model of base 2, fix the jetting part 3 to the corresponding liquid outlet pipe 22 with screws, connect the liquid supply device pipeline to the liquid inlet pipe 23, start the liquid supply device, and the high pressure water pump will pressurize the water and deliver it to the liquid storage chamber 21 of the base 2, and finally deliver it to each liquid outlet pipe 22.

[0075] Each nozzle 3 simultaneously ejects high-pressure water jets. The water jet ejected from the second nozzle 32 generates a reverse thrust, driving the base 2 forward along the stuck drill rod 1. The high-pressure jet beam ejected from the first nozzle 31 clears away coal slag, rock powder, and other encapsulated materials on the travel path and breaks up obstacles in front. At the same time, the loose material that is cleared away is discharged backward with the help of the water jet and the thrust of the second nozzle 32, preventing secondary accumulation of material.

[0076] As the package is cleared, enough space will gradually form around the stuck drill rod 1, thus gradually relieving the stuck situation and eventually freeing the drill rod 1.

[0077] Operators can judge the cleaning progress based on changes in water supply pressure and the condition of the backflow carrying debris. When the device reaches the end of the stuck drill area, or when the resistance is significantly reduced by attempting to move drill rod 1 with the help of a drilling rig, it indicates that sufficient space has been cleared around drill rod 1. At this point, drill rod 1 can be removed by normal rotation or lifting operations using the drilling rig.

[0078] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other modifications under the guidance of the present invention without departing from the spirit and scope of the claims, and all of these modifications are within the protection scope of the present invention.

Claims

1. A hydraulic unblocking device for a stuck drill bit, characterized in that, include: A base for being movably fitted onto the outside of the drill pipe; A jetting component is disposed on the base. The jetting component has a first nozzle and a second nozzle. Both the first nozzle and the second nozzle are used to communicate with a liquid supply device. The first nozzle is positioned towards the bottom wall of the borehole, and the second nozzle is positioned towards the side wall of the borehole. The second nozzle is positioned at an angle to the first nozzle, and the second nozzle is used to jet liquid onto the side wall of the borehole to drive the base to move toward the bottom wall of the borehole.

2. The hydraulic unblocking device for stuck drill bits as described in claim 1, characterized in that, The spraying element is provided in at least two parts, and each spraying element is arranged at intervals along the circumference of the base.

3. The hydraulic unblocking device for stuck drill bits according to claim 2, characterized in that, The base is provided with a liquid storage chamber, which is used to connect with the liquid supply device. The first nozzle and the second nozzle of each of the spray elements are connected to the liquid storage chamber.

4. The hydraulic unblocking device for stuck drill bits according to claim 3, characterized in that, The liquid storage chamber is connected to at least two liquid outlet pipes, and the liquid outlet pipes are detachably connected to the spraying elements one by one. The first nozzle and the second nozzle of each spraying element are connected to the corresponding liquid outlet pipe.

5. The hydraulic unblocking device for stuck drill bits according to claim 4, characterized in that, The spraying element is equipped with a sealing element, and the spraying element is sealed to the inner wall of the liquid outlet pipe through the sealing element.

6. The hydraulic unblocking device for stuck drill bits according to claim 5, characterized in that, The liquid storage chamber is connected to at least one liquid inlet pipe, each of the liquid inlet pipes is used to connect to the liquid supply device, and each of the liquid inlet pipes may be selectively coaxially arranged and directly connected to one of the liquid outlet pipes.

7. The hydraulic unblocking device for stuck drill bits according to claim 1, characterized in that, The spraying component is provided with at least two first nozzles, which are distributed circumferentially along the spraying component, and each first nozzle is inclined relative to the axis of the spraying component, and the spraying direction of each first nozzle is different.

8. The hydraulic unblocking device for stuck drill bits according to claim 1, characterized in that, The spraying component is provided with at least two second nozzles, which are distributed circumferentially along the spraying component, and each second nozzle is inclined relative to the axis of the spraying component, and the spraying direction of each second nozzle is different.

9. The hydraulic unblocking device for stuck drill bits according to claim 1, characterized in that, The base is provided with a rolling assembly, which includes at least two rolling elements. The rolling elements are arranged at intervals along the circumference of the base, and each rolling element is movably disposed on the inner side of the base. The rolling elements are used to contact the drill rod.

10. The hydraulic unblocking device for stuck drill bits according to claim 9, characterized in that, The rolling assembly is provided in at least two parts, and each rolling assembly is arranged sequentially along the axial direction of the base.

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