PDC drill bit with damping function

Abstract

The utility model discloses a PDC (Polycrystalline Diamond Compact) drill bit with a damping function, which relates to the technical field of well drilling exploration and comprises a connector main body and a drill bit main body, the drill bit main body and the connector main body can move relatively in the axial direction and cannot rotate relatively in the circumferential direction, and the drill bit main body and the connector main body are sealed in a sliding manner; an elastic element is further installed between the drill bit body and the connector body. According to the PDC drill bit, vibration force generated in the drilling process of the PDC drill bit can be absorbed and consumed through the elastic elements, the phenomenon that the PDC drill bit jumps can be effectively avoided, the service life of the PDC drill bit is guaranteed, and meanwhile the PDC drill bit is simple in structure, convenient to machine and low in production cost.

Description

Technical Field

[0001] The utility model relates to the technical field of drilling exploration, in particular to a PDC drill bit with a shock absorbing function. Background Art

[0002] The drill bit is the main tool for breaking rocks during oil drilling. There are three main ways to break rocks: cutting and shearing; chiseling; chiseling and shearing.

[0003] Among them, PDC drill bits have a higher mechanical penetration rate and a longer service life, and have become the most widely used oil drill bits on site. However, PDC drill bits are extremely sensitive to formation conditions and are more suitable for drilling soft to medium-hard homogeneous formations. When PDC drill bits are drilling in hard formations or special formations (such as conglomerate), the cutting teeth are easily subjected to large impact loads, causing tooth collapse and losing cutting ability.

[0004] During the drilling process, due to the complex bottom hole conditions, especially in operations in high-angle wells, horizontal wells and small wellbores, the drill string is subjected to very harsh operating conditions. Therefore, the drill bit and drill pipe will definitely vibrate, which will not only cause the PDC drill bit to shift in the horizontal direction, but also easily cause the PDC drill bit to break teeth, thereby causing the PDC drill bit to fail early and increase drilling costs.

[0005] Although there are shock-absorbing drill bits with similar functions on the market, their structures are generally complex and the manufacturing cost is high; therefore, there is an urgent need for a PDC drill bit with shock-absorbing function. Utility Model Content

[0006] The purpose of the utility model is to provide a PDC drill bit with a shock absorbing function, so that the vibration force generated by the PDC drill bit during the drilling process can be absorbed and consumed by the elastic element, which can effectively avoid the drill jumping phenomenon of the PDC drill bit and ensure the service life of the PDC drill bit. At the same time, the utility model has a simple structure, is easy to process and has a low production cost.

[0007] In order to achieve the purpose of the utility model, the technical solution adopted is: a PDC drill bit with a shock absorbing function, including a joint body and a drill bit body, the drill bit body and the joint body can move axially relative to each other but cannot rotate circumferentially relative to each other, and the drill bit body and the joint body are slidingly sealed; an elastic element is also installed between the drill bit body and the joint body.

[0008] Furthermore, the connector body has a plug-in hole, the drill body includes a connecting end and a drill end, the connecting end is inserted into the plug-in hole, and the elastic element is sleeved on the connecting end and pressed against the step surface of the plug-in hole.

[0009] Furthermore, the connecting end and the plug hole are both three-section structures, and the elastic element is sleeved on the middle part of the connecting end.

[0010] Furthermore, the elastic element is a disc spring.

[0011] Furthermore, the inner end of the connecting end is inserted into the inner hole of the joint body.

[0012] Furthermore, the inner end face of the connecting end is funnel-shaped.

[0013] Furthermore, both ends of the connecting end are provided with sealing rings for sealingly cooperating with the joint body.

[0014] Furthermore, a guide key is provided on the joint body, and a keyway which is slidably matched with the guide key is provided on the drill bit body.

[0015] Furthermore, a guide key is provided on the drill body, and a keyway which is slidably matched with the guide key is provided on the joint body.

[0016] Furthermore, there are multiple guide keys, and the multiple guide keys are evenly spaced and arranged along the circumferential direction of the joint body.

[0017] The beneficial effects of the utility model are:

[0018] The higher the speed of the PDC drill bit, the lower its speed will be slower, and the shorter the drill bit will be, the higher the speed will be.It is a very good practice to increase the speed of the PDC drill bit to a small extent, so that the longer the PDC drill bit is, the lower its speed will be slower, and the shorter the drill bit will be. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The accompanying drawings illustrate exemplary embodiments of the present invention and are used to explain the principles of the present invention together with the description. These drawings are included to provide a further understanding of the present invention, and the drawings are included in and constitute a part of this specification.

[0020] Figure 1 It is a structural schematic diagram of a PDC drill bit with a shock absorbing function provided by the utility model.

[0021] Markings and corresponding parts names in the attached drawings:

[0022] 1. Drill bit body, 2. Joint body, 3. Elastic element, 4. Sealing ring;

[0023] 11. Drill end, 12. Connecting end, 13. Keyway;

[0024] 21. Plug hole, 22. Guide key. DETAILED DESCRIPTION

[0025] The present invention is further described in detail below in conjunction with the accompanying drawings and implementations. It is to be understood that the specific implementations described herein are only used to explain the relevant content, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention are shown in the accompanying drawings.

[0026] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0027] like Figure 1 As shown, the utility model provides a PDC drill bit with a shock absorbing function, comprising a joint body 2 and a drill bit body 1, wherein the joint body 2 is used to connect the drill bit body 1 and the transmission shaft assembly; the drill bit body 1 can reciprocate along its axial direction on the joint body 2, but the drill bit body 1 cannot rotate on the joint body 2, so that during the drilling process of the drill bit, the transmission shaft assembly drives the drill bit body 1 to rotate through the connecting body, and the drill bit body 1 can shake up and down, thereby achieving shock absorption during the drilling process of the drill bit.

[0028] During the drilling process, the drill bit needs to spray mud while cutting, that is, the joint body 2 and the drill bit have inner holes for mud to flow, so in order to prevent the mud from leaking from between the joint body 2 and the drill bit body 1, the drill bit body 1 and the joint body 2 need to be sealed. In the present utility model, while the drill bit body 1 and the joint body 2 are sealed, it is also necessary to ensure that the drill bit body 1 can move axially on the joint body 2, so a sliding seal can be used between the drill bit body 1 and the joint body 2.

[0029] In order to avoid the vibration of the drill bit being transmitted to the drill rod part as much as possible, an elastic element 3 is also installed between the drill bit body 1 and the joint body 2. On the one hand, the elastic element 3 can absorb and consume the vibration generated by the drill bit body 1. On the other hand, the elastic element 3 can also push the drill bit body 1 to reset after the drill bit body 1 is displaced, so that the drill bit body 1 is always pressed against the formation during the process of cutting the formation, so that the cutting effect of the formation is guaranteed.

[0030] In the utility model, a plug-in hole 21 is provided at one end of the joint body 2 connected to the brick body, the aperture of the plug-in hole 21 is larger than the inner hole diameter of the joint body 2, and the central axis of the plug-in hole 21 is in the same straight line with the central axis of the joint body 2; at the same time, the drill bit body 1 also includes a connecting end 12 and a drill bit end 11, the end of the drill bit body 1 connected to the joint body 2 is the connecting end 12, and the end of the drill bit body 1 for cutting the formation is the drill bit end 11. When installing the drill bit body 1, the connecting end 12 is inserted into the plug-in hole 21, and the elastic element 3 is sleeved on the connecting end 12, one end of the elastic element 3 is pressed against the step surface of the connecting end 12, and the other end of the elastic element 3 is pressed against the step surface of the plug-in hole 21.

[0031] When the drill body 1 is not subjected to force, the elastic element 3 pushes the drill body 1 away from the connection body through its own elastic force, so that the drill body 1 and the connection remain stable; when the drill bit is cutting the formation, the drill body 1 is subjected to a force reaction force, and the drill body 1 applies the force received to the elastic element 3, and the elastic element 3 is compressed. When the drill body 1 vibrates when the drill bit is cutting the formation, the drill body 1 transmits the vibration force to the elastic element 3, and the elastic element 3 absorbs the vibration force, so that the vibration received by the drill body 1 will not be transmitted to the joint body 2, thereby realizing the shock absorption function.

[0032] In the present invention, the connection end 12 and the plug hole 21 are both three-section structures. Specifically, the diameter of the connection end 12 gradually decreases from the drill end 11 to the end of the connection body, that is, the diameter of the connection end 12 near the drill body 1 is the largest, and the diameter of the connection end 12 near the end of the connection body is the smallest. The inner diameter of the plug hole 21 is adapted to the diameter of the connection end 12. Specifically, a large diameter section of the plug hole 21 is gap-matched with a large diameter section of the connection end 12, the diameter of the middle section of the plug hole 21 is adapted to the diameter of the elastic element 3, and a small diameter section of the plug hole 21 is gap-matched with the middle section of the connection end 12. The inner hole of the joint body 2 is gap-matched with a small diameter section of the connection end 12. Therefore, when the connection end 12 is installed, a small diameter section of the connection end 12 is inserted into the inner hole of the joint body 2.

[0033] The elastic element 3 in the present invention is a disc spring. Of course, under the condition that the elastic element 3 has a sufficiently large elastic force, the elastic element 3 can also be a telescopic spring, a high-strength rubber pad, etc.

[0034] In order to avoid turbulence caused by the end face of the connecting end 12 when the mud enters the drill bit body 1 from the connecting body, the end face of the connecting end 12 inserted in one end of the inner hole of the joint body 2 can also be set to be funnel-shaped, so that the mud can be guided by the end face of the connecting end 12 and gradually gathered when entering the drill bit body 1 from the connecting body, which can not only effectively reduce the thrust exerted by the mud on the drill bit body 1, but also make the flow of the mud smoother.

[0035] In the present invention, in order to prevent the mud from leaking from between the joint body 2 and the drill bit body 1, both ends of the connection end 12 are embedded with sealing rings 4 for sealing with the joint body 2, so that after the drill bit body 1 is installed on the connection body, the drill bit body 1 and the connection body are kept in sliding seal. There can be multiple sealing rings 4 embedded at both ends of the connection end 12, and the multiple sealing rings 4 are arranged at intervals along the axial direction of the connection end 12.

[0036] In order to ensure that the drill body 1 can move axially but not rotate on the joint body 2, a guide key 22 is also provided on the wall of the plug hole 21 of the joint body 2, and a key slot 13 is also provided on the outer wall of the connection end 12 of the drill body 1 for sliding cooperation with the guide key 22. The length of the key slot 13 is greater than the length of the guide key 22, and the sliding distance of the guide key 22 in the key slot 13 needs to meet the expansion and contraction of the elastic element 3. In order to make the drill body 1 more stable on the connection body, the guide key 22 is set in the large diameter section of the plug hole 21. In order to further make the drill body 1 more stable on the connection body, there can be multiple guide keys 22 on the connection body, and the multiple guide keys 22 are evenly spaced and arranged along the circumferential direction of the connection body; when there are multiple guide keys 22, there are also multiple key slots 13 on the drill body 1, and the multiple key slots 13 correspond to the multiple guide keys 22 one by one.

[0037] In the utility model, while ensuring that the drill body 1 can move axially but not rotate on the joint body 2, the keyway 13 can be opened on the wall of the plug-in hole 21 of the connecting body, and the guide key 22 can be set on the outer wall of the connecting end 12 of the drill body 1. However, the connecting body needs to have the keyway 13 and its structural strength must be ensured at the same time.

[0038] In the utility model, while ensuring the shock absorption effect, the connecting body can also be inserted into the drill body 1. At this time, the plug hole 21 is opened on the drill body 1, and the end of the connecting body inserted into the plug hole 21 is the connecting end 12. The shape of the plug hole 21 and the shape of the connecting end 12 remain unchanged, and the elastic element 3 is still sleeved on the connecting end 12 of the connecting body.

[0039] In the description of this specification, the description with reference to the terms "one embodiment / method", "some embodiments / methods", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment / method or example are included in at least one embodiment / method or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment / method or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments / methods or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments / methods or examples described in this specification and the features of the different embodiments / methods or examples, unless they are contradictory.

[0040] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0041] Those skilled in the art should understand that the above embodiments are only for the purpose of clearly illustrating the present invention, and are not intended to limit the scope of the present invention. For those skilled in the art, other changes or modifications may be made based on the above disclosure, and these changes or modifications are still within the scope of the present invention.

Claims

1. A PDC drill bit with a shock absorbing function, characterized in that: The invention comprises a joint body (2) and a drill body (1); the drill body (1) and the joint body (2) can move axially relative to each other but cannot rotate circumferentially relative to each other, and the drill body (1) and the joint body (2) are slidingly sealed; an elastic element (3) is also installed between the drill body (1) and the joint body (2).

2. The PDC drill bit with shock absorption function according to claim 1, characterized in that: The joint body (2) has a plug hole (21) therein, the drill body (1) comprises a connecting end (12) and a drill end (11), the connecting end (12) is inserted into the plug hole (21), and the elastic element (3) is sleeved on the connecting end (12) and tightly abuts against the step surface of the plug hole (21).

3. The PDC drill bit with shock absorption function according to claim 2, characterized in that: The connecting end (12) and the plug hole (21) are both three-section structures, and the elastic element (3) is sleeved on the middle part of the connecting end (12).

4. The PDC drill bit with shock absorption function according to claim 1, 2 or 3, characterized in that: The elastic element (3) is a disc spring.

5. The PDC drill bit with shock absorption function according to claim 3, characterized in that: The inner end of the connecting end (12) is inserted into the inner hole of the joint body (2).

6. The PDC drill bit with shock absorption function according to claim 3, characterized in that: The inner end face of the connecting end (12) is funnel-shaped.

7. The PDC drill bit with shock absorption function according to claim 3, characterized in that: Both ends of the connection end (12) are provided with sealing rings (4) for sealingly cooperating with the joint body (2).

8. The PDC drill bit with shock absorption function according to any one of claims 1, 2, 3, 5, 6 or 7, characterized in that: The joint body (2) is also provided with a guide key (22), and the drill body (1) is also provided with a keyway (13) that is slidably matched with the guide key (22).

9. The PDC drill bit with shock absorption function according to any one of claims 1, 2, 3, 5, 6 or 7, characterized in that: The drill bit body (1) is also provided with a guide key (22), and the joint body (2) is also provided with a keyway (13) that is slidably matched with the guide key (22).

10. The PDC drill bit with shock absorption function according to claim 8, characterized in that: There are a plurality of guide keys (22), and the plurality of guide keys (22) are evenly spaced and arranged along the circumferential direction of the joint body (2).

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