A borehole apparatus for fracturing a formation

Abstract

The embodiment of the present application discloses a drilling device for breaking stratum, relates to the field of well and tunnel blasting drilling construction, and can effectively improve the operation stability and construction efficiency of a drill bit and a drill rod during drilling construction. The device comprises a rod body, a drilling body and a guide groove. The first end of the rod body is provided with a guide hole in the axial direction from the first end to the second end. The first end of the rod body is configured to be connected with a driving mechanism. The drilling body is arranged at the second end of the rod body. The drilling body comprises two or more punching teeth distributed in the circumferential direction. The base of the punching tooth is formed at the second end of the rod body. The first cutting edge and the first blade tip are formed by extending from the base. The first end of the first cutting edge is terminated at the first blade tip. The distance between the first blade tip and the axis of the rod body is greater than the outer diameter of the rod body. The guide groove is arranged between the circumferentially adjacent punching teeth of the drilling body. The guide groove starts at the through position of the guide hole at the second end of the rod body and extends to the outer wall of the rod body in the radial direction of the rod body. The present application is suitable for drilling construction scenes.

Description

Technical Field

[0001] This application relates to the field of tunnel blasting drilling construction, specifically to a drilling device for fractured strata. Background Technology

[0002] Complex and fractured strata are unstable rock formations formed by geological bodies under the influence of tectonic factors such as faults and folds. They are widely distributed in my country. These strata generally have well-developed bedding and foliation, and their attitude varies greatly. The rocks or superstructures in these strata are uneven in hardness, and their elasticity, plasticity, and water solubility vary greatly. There are many faults and fractures. Drilling operations in such environments will face many challenges, such as high drilling pressure and difficulty in removing drill cuttings. Furthermore, during drilling in fractured strata, the lateral vibration of the drill rod can easily cause local rock instability in the borehole wall, leading to rock falling into the bottom of the hole and causing the drill bit to get stuck. This makes it difficult to rotate and raise or lower the drill bit. In severe cases, it can directly cause the borehole wall to collapse, making it impossible for the drill bit to operate normally, resulting in major engineering accidents such as stuck drill bit or buried drill bit. Furthermore, existing drill bits and drill pipes are mainly connected by mechanical methods such as pin-type, threaded, and toothed types. When the drill bit passes through heterogeneous strata during drilling, these traditional mechanical connection methods are prone to drill jumping, which generates strong vibration loads and shear stresses, causing the connection between the drill bit and drill pipe to loosen, or even causing the drill bit to fall off, inducing engineering accidents, delaying the construction period, and causing huge losses of manpower, material resources, and financial resources.

[0003] Therefore, in order to address a series of challenges encountered in drilling operations in fractured formations, there is an urgent need to develop a new type of drilling tool that can provide stable transmission, stable connection between the drill bit and drill rod, minimal disturbance to the formation during drilling, prevent stuck drill bits and burial, and has high slag removal efficiency. Summary of the Invention

[0004] In view of this, this application provides a drilling device for fractured formations to improve the operational stability and construction efficiency of the drill bit and drill rod during drilling operations in fractured formations.

[0005] This invention provides a drilling device for fracturing formations, comprising:

[0006] A rod body, wherein a guide hole is provided axially from a first end to a second end, and the first end of the rod body is configured to be connected to a drive mechanism;

[0007] A drill cutting body is disposed at the second end of the rod body. The drill cutting body includes two or more punching teeth distributed circumferentially. The base of the punching teeth is formed at the second end of the rod body, and a first cutting edge and a first cutting tip extend from the base. The first end of the first cutting edge terminates at the first cutting tip. The distance between the first cutting tip and the axis of the rod body is greater than the outer diameter of the rod body.

[0008] The guide groove is provided between the circumferentially adjacent punching teeth of the drill cutting body. The guide groove starts at the through position of the guide hole at the second end of the rod body and extends radially to the outer wall of the rod body.

[0009] In one specific implementation, the punching tooth extends from the base to the first cutting tip and forms at least a first cutting surface, a second cutting surface, and an arc surface. The arc surface is located on the side of the punching tooth facing away from the axis of the rod and is in contact with the outer wall of the rod. The first cutting surface and the second cutting surface are located on the side of the punching tooth facing the axis of the rod. The first cutting surface and the second cutting surface intersect to form the first cutting edge. The first cutting edges of each punching tooth of the drill bit are located in the same plane perpendicular to the axis of the rod.

[0010] In one specific implementation, the first tangent, the second tangent, and the arc surface intersect to form the first cutting tip of the punching tooth, and the cross-sectional dimension of the solid formed by the first tangent, the second tangent, and the arc surface gradually decreases as they extend towards the first cutting tip of the punching tooth.

[0011] In one specific implementation, the punching tooth extends from the base to the first cutting tip and forms a third cutting surface and a fourth cutting surface. The third cutting surface starts from the second end of the rod and extends to intersect the second cutting surface to form a second cutting edge. The fourth cutting surface starts from the second end of the rod and extends to intersect the first cutting surface to form a third cutting edge. The third cutting surface and the fourth cutting surface intersect to form a fourth cutting edge.

[0012] In one specific implementation, the first, second, third, and fourth cutting surfaces intersect to form the second cutting tip of the punching tooth, the second end of the first cutting edge terminates at the second cutting tip, and the distance between the second cutting tip and the axis of the rod body is smaller than the distance between the first cutting tip and the axis of the rod body.

[0013] In one specific implementation, the first cutting surface intersects with the arc surface to form a fifth cutting edge, and the second cutting surface intersects with the arc surface to form a sixth cutting edge.

[0014] In one specific implementation, a guide groove is formed between the fourth facet of each of the punching teeth of the drill body and the third facet of the circumferentially adjacent punching teeth.

[0015] In one specific implementation, the third and fourth facets of the punching teeth are parallel to the axis of the rod.

[0016] In one specific implementation, the drill bit is provided with four punching teeth along the circumferential direction.

[0017] In one specific implementation, the rod body and the drill cutting body are an integrated structure.

[0018] An embodiment of the present invention provides a drilling device for breaking formations, comprising: a rod body, a drilling cutter, and a guide groove; wherein, a guide hole is provided axially from a first end to a second end of the rod body, and the first end of the rod body is configured to be connected to a drive mechanism; the drilling cutter is disposed at the second end of the rod body, and the drilling cutter includes two or more circumferentially distributed punching teeth, the base of the punching teeth is formed at the second end of the rod body, and a first cutting edge and a first cutting tip extend from the base, the first end of the first cutting edge terminates at the first cutting tip, and the distance of the first cutting tip from the axis of the rod body is greater than the outer diameter of the rod body; the guide groove is provided between adjacent punching teeth along the circumferential direction of the drilling cutter, the guide groove starts at the through position of the guide hole at the second end of the rod body, and extends radially along the rod body to the outer wall of the rod body. When the device is drilling, the rock cuttings generated will gather in the guide groove as the cutting teeth rotate. Under the action of the gas blown out of the guide hole, they will be discharged from the borehole along the rock cuttings discharge channel formed by the gap between the guide groove, the outer wall of the rod body and the borehole. The device causes little disturbance to the formation during drilling, the rock cuttings are discharged smoothly, and the construction is stable and efficient. Attached Figure Description

[0019] 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.

[0020] Figure 1 A schematic diagram of a drilling device for fractured formations provided in this application embodiment;

[0021] Figure 2 This is a partial schematic diagram of a drilling device for fracturing formations provided in an embodiment of this application;

[0022] Figure 3 A front view of a drilling device for fracturing formations provided in an embodiment of this application;

[0023] Figure 4 A bottom view of a drilling device for fracturing formations provided in an embodiment of this application;

[0024] Figure 5 A cross-sectional view AA of a drilling device for fracturing formations provided in an embodiment of this application;

[0025] Figure 6A cross-sectional view of a drilling device for fracturing formations provided in this application embodiment.

[0026] Explanation of key figure labels:

[0027] 10-Bar body; 101-Guide hole; 20-Drilling body; 201-Punching tooth; 2011-Base; 2012-First cutting tip; 2013-First cutting surface; 2014-Second cutting surface; 2015-Arc surface; 2016-First cutting edge; 2017-Third cutting surface; 2018-Fourth cutting surface; 2019-Second cutting edge; 2020-Third cutting edge; 2021-Fourth cutting edge; 2022-Second cutting tip; 2023-Fifth cutting edge; 2024-Sixth cutting edge; 30-Guide groove. Detailed Implementation

[0028] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0029] It should be understood that the described embodiments are merely some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0030] Existing drill bits and drill pipes are mainly connected using mechanical methods such as pin-type, threaded, and toothed connections. However, when the drill bit passes through heterogeneous strata during drilling, these traditional mechanical connection methods are prone to drill jumps, generating strong vibration loads and shear stresses. This can loosen the connection between the drill bit and drill pipe, even causing the drill bit to fall off, inducing engineering accidents, delaying the project schedule, and resulting in huge losses of manpower, material resources, and financial resources. Therefore, in order to improve the operational stability and construction efficiency of drill bits and drill pipes during drilling operations in fractured strata, such as... Figure 1 , Figure 2 As shown, an embodiment of the present invention provides a drilling device for fracturing formations. The device may include a rod 10, a drill bit 20, and a guide groove 30. A guide hole 101 is provided axially from a first end to a second end of the rod 10, and the first end of the rod 10 is configured to connect to a drive mechanism. The drill bit 20 is disposed at the second end of the rod 10 and includes two or more circumferentially distributed cutting teeth 201. The base 2011 of the cutting teeth 201 is formed at the second end of the rod 10. A first cutting edge 2016 and a first cutting tip 2012 are formed extending from the base 2011. The first end of the first cutting edge 2016 terminates at the first cutting tip 2012. The distance between the first cutting tip 2012 and the axis of the rod 10 is greater than the outer diameter of the rod 10. A guide groove 30 is provided between the circumferentially adjacent punching teeth 201 of the drill cutting body 20. The guide groove 30 starts at the through position of the guide hole 101 at the second end of the rod 10 and extends radially along the rod 10 to the outer wall of the rod 10.

[0031] In this embodiment, under the rotation of the drive mechanism, the first cutting edge 2016 of the multiple punching teeth 201 of the drill cutting body 20 can rotate and cut the rock of the fractured strata. Compared with the traditional drill bit and drill rod, which are prone to loosening and dropping due to mechanical connection, this drilling device integrates the traditional drill bit and drill rod, has stronger structural stability, and is easy to assemble and use on site. In addition, since the distance between the first cutting edge 2012 of each punching tooth 201 and the axis of the rod 10 is greater than the outer diameter of the rod 10, the structure of the punching teeth 201 radiating outwards can make the inner diameter of the drill hole larger than the outer diameter of the rod 10. This helps to reduce the impact of the lateral vibration of the rod 10 on the borehole wall during drilling, weaken the disturbance to the strata, and thus reduce the probability of stuck drill and buried drill accidents. At the same time, it can make the contact between the drill cutting body 20 and the rock at the bottom of the borehole more stable and prevent the drilling trajectory from deviating. Furthermore, the guide hole 101 can be set in the middle of the rod body 10. The port of the guide hole 101 at the second end of the rod body 10 can be set in the middle of each guide groove 30 distributed along the circumferential direction. The position of the guide hole 101 will not change with the rotation of the rod body 10, and the airflow is more stable. Since the distance between the first cutting tip 2012 and the axis of the rod body 10 is greater than the outer diameter of the rod body 10, it can form an airflow channel together with the guide hole 101 set along the axial direction of the rod body 10 and the guide groove 30 set between the punching teeth 201 adjacent to the drill cutting body 20 along the circumferential direction. Under the action of the high-pressure airflow introduced into the guide hole 101, the rock cutting generated during the drilling process can be discharged in time. Preferably, the ratio of the distance between the first cutting tip 2012 and the axis of the rod 10 to the outer diameter of the rod 10 is in the range of 1.2 to 1.35, so as to ensure that a sufficient and effective slag discharge channel is formed between the outer wall of the rod 10 and the inner wall of the borehole, while ensuring the structural strength of the drill cutting body 20 and the rod 10; in addition, the second end of the rod 10 and the drill cutting body 20 can be configured with an arc-shaped transition structure to further reduce structural stress and improve the connection strength between the drill cutting body 20 and the rod 10.

[0032] The drilling device for fracturing formations provided in the embodiments of the present invention includes a rod body 10, a drill cutting body 20, and a guide groove 30; wherein, a guide hole 101 is provided axially from a first end to a second end of the rod body 10, and the first end of the rod body 10 is configured to be connected to a drive mechanism; the drill cutting body 20 is disposed at the second end of the rod body 10, and the drill cutting body 20 includes two or more circumferentially distributed punching teeth 201, the base 2011 of the punching teeth 201 being formed at the second end of the rod body 10, and the base 2011 being formed at the second end of the rod body 10. The first cutting edge 2016 and the first cutting tip 2012 are formed by the extension of the first cutting edge 2011. The first end of the first cutting edge 2016 terminates at the first cutting tip 2012. The distance between the first cutting tip 2012 and the axis of the rod body 10 is greater than the outer diameter of the rod body 10. A guide groove 30 is provided between the circumferentially adjacent punching teeth 201 of the drill cutting body 20. The guide groove 30 starts at the through position of the guide hole 101 at the second end of the rod body 10 and extends radially to the outer wall of the rod body 10. When the device drills, the rock cuttings generated will gather in the guide groove 30 as the punching teeth 201 rotate. Under the action of the gas blown out of the guide hole 101, they will be discharged from the borehole along the rock cuttings discharge channel formed by the gap between the guide groove 30, the outer wall of the rod body 10 and the borehole. The device causes little disturbance to the formation during drilling, ensures smooth rock cuttings discharge, and provides stable and efficient construction.

[0033] Optionally, in one embodiment of the present invention, the punching tooth 201 extends from the base 2011 to the first cutting tip 2012 and forms at least a first cutting surface 2013, a second cutting surface 2014, and an arc surface 2015. The arc surface 2015 is located on the side of the punching tooth 201 facing away from the axis of the rod 10 and is in contact with the outer wall of the rod 10. The first cutting surface 2013 and the second cutting surface 2014 are located on the side of the punching tooth 201 facing the axis of the rod 10. The first cutting surface 2013 and the second cutting surface 2014 intersect to form a first cutting edge 2016. The first cutting edge 2016 of each punching tooth 201 of the drill cutting body 20 is located in the same plane perpendicular to the axis of the rod 10.

[0034] like Figure 3 As shown, an arc surface 2015 is provided on the side of the punching tooth 201 facing away from the axis of the rod 10, which can reduce the friction between the drilling device and the hole wall during the working rotation, thereby ensuring the kinetic energy required for the cutting operation of the drill cutting body 20; the first cutting surface 2013 and the second cutting surface 2014 intersect to form the first cutting edge 2016, and the first cutting edge 2016 of each punching tooth 201 of the drill cutting body 20 is located on the same plane perpendicular to the axis of the rod 10, thereby forming a cutting drilling action surface for rock.

[0035] Optionally, in one embodiment of the present invention, the first cutting surface 2013, the second cutting surface 2014 and the arc surface 2015 intersect to form the first cutting tip 2012 of the punching tooth 201, and the cross-sectional size of the solid formed by the first cutting surface 2013, the second cutting surface 2014 and the arc surface 2015 gradually decreases as they extend toward the first cutting tip 2012 of the punching tooth 201.

[0036] The above structure allows the punching tooth 201 to form a structure that is wider inside and narrower outside as it extends towards the first cutting tip 2012. This results in the inner diameter of the borehole obtained by cutting the rock being larger than the outer diameter of the rod body 10. This creates a sufficient gap between the borehole wall and the rod body 10, making the slag discharge air path smoother, facilitating timely removal of rock cuttings, improving rock breaking efficiency, and increasing the rock cuttings collection rate, making it easier to identify the lithology.

[0037] Optionally, in one embodiment of the present invention, the punching tooth 201 extends from the base 2011 to the first cutting tip 2012 and is further formed with a third cutting surface 2017 and a fourth cutting surface 2018. The third cutting surface 2017 starts from the second end of the rod 10 and extends to intersect with the second cutting surface 2014 to form a second cutting edge 2019. The fourth cutting surface 2018 starts from the second end of the rod 10 and extends to intersect with the first cutting surface 2013 to form a third cutting edge 2020. The third cutting surface 2017 and the fourth cutting surface 2018 intersect to form a fourth cutting edge 2021.

[0038] like Figure 1 As shown, the third cut surface 2017 and the fourth cut surface 2018 facilitate the formation of a space for receiving rock cuttings and a slag discharge channel, while also providing structural support for the extension of the first cutting edge 2016. To further facilitate the discharge of rock cuttings, optionally, in one embodiment of the invention, the third cut surface 2017 and the fourth cut surface 2018 of the punching tooth 201 are parallel to the axis of the rod 10. With the third cut surface 2017 and the fourth cut surface 2018 parallel to the axis of the rod 10, and parallel to the drilling direction, the rock cuttings directly enter the guide groove 30 and are discharged under the action of high-pressure airflow, thereby improving operating efficiency and avoiding drill jamming due to rock cuttings accumulating and not being discharged in time.

[0039] Optionally, in one embodiment of the present invention, the first cutting surface 2013, the second cutting surface 2014, the third cutting surface 2017, and the fourth cutting surface 2018 intersect to form the second cutting tip 2022 of the punching tooth 201, the second end of the first cutting edge 2016 terminates at the second cutting tip 2022, and the distance between the second cutting tip 2022 and the axis of the rod 10 is smaller than the distance between the first cutting tip 2012 and the axis of the rod 10.

[0040] The second cutting tip 2022 is located near the axis of the rod body 10 and together with the first cutting tip 2012, forms the two-end support of the first cutting edge 2016, providing structural strength for the first cutting edge 2016 and ensuring that the first cutting edge 2016 has sufficient cutting length, making the contact between the punching tooth 201 and the rock at the bottom of the hole more stable. This not only prevents the drilling trajectory from deviating, but also ensures the cutting efficiency of the first cutting edge 2016 on the rock.

[0041] Optionally, in one embodiment of the present invention, the first cutting surface 2013 intersects with the arc surface 2015 to form a fifth cutting edge 2023, and the second cutting surface 2014 intersects with the arc surface 2015 to form a sixth cutting edge 2024.

[0042] like Figure 1 , Figure 4 As shown, the fifth cutting edge 2023, the sixth cutting edge 2024, the first cutting edge 2016, the second cutting edge 2019, and the third cutting edge 2020 form the edge of the cone structure. The fifth cutting edge 2023, the sixth cutting edge 2024, and the first cutting edge 2016 extend and converge to form the first cutting tip 2012. This causes the size of the solid cross section formed by the first cutting surface 2013, the second cutting surface 2014, and the arc surface 2015 as they extend toward the first cutting tip 2012 of the punching tooth 201 to gradually decrease, thereby constructing a high-efficiency cutting structure for the punching tooth 201 and ensuring the operational stability of the device during drilling. Preferably, the arc surface 2015 is part of the side surface of a frustum, which is coaxial with the rod 10. The first cutting tip 2012, the fifth cutting edge 2023, and the sixth cutting edge 2024 are located on the side surface of the frustum. Thus, during drilling, the rock cuttings between the arc surface 2015 and the inner wall of the borehole, under the action of force, form a first relative friction distance along the circumference of the frustum and a second relative friction distance along the generatrix of the frustum. The structural design of the arc surface 2015 ensures that the arc surface 2015 interacts with the first cutting edge 2013, the second cutting edge 2014, and the sixth cutting edge 2024. With sufficient structural strength, the solid structure enclosed by the three-section 2017 and the fourth-section 2018 allows for a smaller first relative friction distance between the rock cuttings between the arc surface 2015 and the inner wall of the borehole, and between the arc surface 2015 and the rock cuttings. Furthermore, since the generatrix of the frustum is straight, the rock cuttings between the arc surface 2015 and the inner wall of the borehole have a smaller second relative friction distance when they move along the arc surface 2015 from the first cutting tip 2012 to the second end of the rod 10 for discharge. This reduces ineffective frictional energy loss and improves the mechanical efficiency of the drilling device.

[0043] Optionally, in one embodiment of the present invention, a guide groove 30 is formed between the fourth cutting surface 2018 of each punching tooth 201 of the drill cutter 20 and the third cutting surface 2017 of the circumferentially adjacent punching tooth 201.

[0044] like Figure 4As shown in this embodiment, the punching teeth 201 of the drill bit 20 are distributed sequentially along the circumference. A guide groove 30 is formed between the fourth cutting surface 2018 of each punching tooth 201 and the third cutting surface 2017 of the adjacent punching tooth 201 in the circumferential direction. This allows each punching tooth 201 to form an independent and efficient cutting structure, resulting in less mutual influence of forces between the punching teeth 201 during drilling. This weakens the impact of uneven forces on the stability of the drilling device when drilling gravel layers, soft and hard interlayers, and heterogeneous rock formations, reducing the probability of drill jumping and achieving stable and efficient drilling. In addition, this structure allows adjacent punching teeth 201 to form sufficient cuttings containment space and slag discharge channels, while ensuring that the heat generated by cutting by each punching tooth 201 can be conducted and discharged in a timely manner, thereby improving the operational stability and construction efficiency of the drilling device.

[0045] Preferably, the outer wall of the rod 10 is provided with multiple spiral grooves around the axis. Each spiral groove intersects with the end of the guide groove 30 at the second end of the rod 10. This allows the rock cuttings discharged from each guide groove 30 to directly enter the spiral groove, and the rock cuttings are discharged along the spiral groove under the rotation of the rod 10, thereby further improving the drilling efficiency.

[0046] To ensure the strength of the drill bit 20 and the construction efficiency during drilling, optionally, in one embodiment of the present invention, the drill bit 20 is provided with four punching teeth 201 along the circumferential direction. For example... Figure 4 As shown, it can be understood that when the number of punching teeth 201 of the drill cutting body 20 is too large, the limited structural space will affect the structural strength of a single punching tooth 201, and will also affect the structural dimensions of the guide groove 30 between adjacent punching teeth 201. A guide groove 30 with too small a size is not convenient for timely discharge of rock cuttings. Therefore, in this embodiment, the number of punching teeth 201 of the drill cutting body 20 is set to four. This structure can also make the opposing guide grooves 30 form a straight structure. Each guide groove 30 forms a cross shape, and the port of the guide hole 101 at the second end of the rod body 10 is located at the center of the cross shape, thereby making the slag discharge channel smoother.

[0047] Optionally, in one embodiment of the present invention, the rod body 10 and the drill cutting body 20 are an integrated structure.

[0048] like Figure 4 , Figure 5 , Figure 6As shown, the rod body 10 and the drill bit 20 are integrally machined, preventing the drilling device from experiencing the additional vibration load and shear stress caused by skipping when drilling into uneven lithology, which can lead to the loosening of the mechanical connection between the drill bit and the drill rod and the drill bit falling off. Preferably, in a specific embodiment of this application, the outer diameter of the rod body 10 of the drilling device is 25mm, the cutting edge 2016 of the punching tooth 201 has a cutting edge length of 25mm, the height of the first cutting edge 2016 from the second end of the rod body 10 is 15mm, the guide groove 30 is 4mm wide and 15mm high, and the inner diameter of the guide hole 101 is 4mm.

[0049] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0050] The various embodiments in this specification are described in a related manner. For the same or similar parts between the various embodiments, please refer to each other. Each embodiment focuses on describing the differences from other embodiments.

[0051] In particular, the device embodiment is basically similar to the method embodiment, so the description is relatively simple. For relevant details, please refer to the description of the method embodiment.

[0052] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A drilling device for fracturing formations, characterized in that, include: A rod body, wherein a guide hole is provided axially from a first end to a second end, and the first end of the rod body is configured to be connected to a drive mechanism; A drill cutting body is disposed at the second end of the rod body. The drill cutting body includes two or more punching teeth distributed circumferentially. The base of the punching teeth is formed at the second end of the rod body, and a first cutting edge and a first cutting tip extend from the base. The first end of the first cutting edge terminates at the first cutting tip. The distance between the first cutting tip and the axis of the rod body is greater than the outer diameter of the rod body. The guide groove is provided between the circumferentially adjacent punching teeth of the drill cutting body. The guide groove starts at the through position of the guide hole at the second end of the rod body and extends radially to the outer wall of the rod body. The punching tooth extends from the base to the first cutting tip and forms at least a first cutting surface, a second cutting surface, and an arc surface. The arc surface is located on the side of the punching tooth facing away from the axis of the rod and is in contact with the outer wall of the rod. The first cutting surface and the second cutting surface are located on the side of the punching tooth facing the axis of the rod. The first cutting surface and the second cutting surface intersect to form the first cutting edge. The first cutting edge of each punching tooth of the drill cutter is located in the same plane perpendicular to the axis of the rod. The first cut surface, the second cut surface and the arc surface intersect to form the first cutting tip of the punching tooth, and the size of the solid cross section enclosed by the first cut surface, the second cut surface and the arc surface gradually decreases as they extend to the first cutting tip of the punching tooth. The rod body and the drill cutting body are an integrated structure; The punching tooth extends from the base to the first cutting tip and forms a third cutting surface and a fourth cutting surface. The third cutting surface starts from the second end of the rod and extends to intersect the second cutting surface to form a second cutting edge. The fourth cutting surface starts from the second end of the rod and extends to intersect the first cutting surface to form a third cutting edge. The third cutting surface and the fourth cutting surface intersect to form a fourth cutting edge. The first cutting surface intersects with the arc surface to form a fifth cutting edge, and the second cutting surface intersects with the arc surface to form a sixth cutting edge; The curved surface is part of the side of the frustum. The frustum is coaxial with the rod. The first cutting tip, the fifth cutting edge, and the sixth cutting edge are located on the side of the frustum. The third and fourth cutting surfaces of the punching teeth are parallel to the axis of the rod.

2. The drilling device for fracturing formations as described in claim 1, characterized in that, The first, second, third, and fourth cutting surfaces intersect to form the second cutting tip of the punching tooth. The second end of the first cutting edge terminates at the second cutting tip. The distance between the second cutting tip and the axis of the rod body is smaller than the distance between the first cutting tip and the axis of the rod body.

3. The drilling device for fracturing formations as described in claim 2, characterized in that, A guide groove is formed between the fourth facet of each of the punching teeth of the drill cutting body and the third facet of the circumferentially adjacent punching teeth.

4. The drilling device for fracturing formations as described in claim 3, characterized in that, The drill bit is provided with four punching teeth along its circumference.

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