PDC bit with impact function

Abstract

The present application belongs to the technical field of oil and gas drilling, and particularly relates to a PDC drill bit with an impact function. The PDC drill bit with the impact function comprises a drill bit body, a channel for the flow of drilling fluid is arranged in the interior of the drill bit body, and a punch that linearly reciprocates at a certain angle with the central axis is arranged in the drill bit body, and the punch is arranged such that one end close to the working end of the drill bit body can exceed the range of the drill bit body in the reciprocating process. The present application can solve the problem that the existing impact drill bit is prone to causing the failure of PDC teeth.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of oil and gas drilling, and particularly relates to a PDC drill bit with an impact function. BACKGROUND

[0002] The PDC drill bit relies on high-hardness, wear-resistant, self-sharpening polycrystalline diamond compact (referred to as PDC tooth or cutting tooth) as a cutting element to shear and break rocks.

[0003] The PDC drill bit has high mechanical drilling speed, long service life and low drilling cost in soft to medium-hard formations, and is therefore widely used in drilling of oil and gas wells.

[0004] Although the PDC tooth has high hardness, due to the limitations of impact resistance and thermal wear resistance, the PDC drill bit is easily subjected to rapid wear and impact collapse of the compact when drilling in hard formations, high-abrasive formations and severely heterogeneous formations (soft and hard staggered layers, gravel-containing layers, etc.), which greatly reduces the cutting efficiency and service life of the drill bit.

[0005] In the existing drilling equipment technical field, an axial or circumferential impactor is arranged on the drill bit to convert the pressure energy of the drilling fluid into kinetic energy of the impactor, and the kinetic energy of the impactor directly acts on the drill bit, which can improve the drilling efficiency of the drill bit to a certain extent. However, the impact resistance of the PDC tooth on the drill bit is limited, and sometimes the PDC tooth is subjected to impact failure, thereby causing premature failure of the entire drill bit. SUMMARY

[0006] In view of the above technical problems, the present application aims to provide a PDC drill bit with an impact function, which can solve the problem that the existing impact drill bit is prone to PDC tooth failure.

[0007] According to the present application, a PDC drill bit with an impact function is provided, comprising a drill bit body, a channel for the flow of drilling fluid is arranged in the interior of the drill bit body,

[0008] An impact head that moves linearly and reciprocally at a certain angle to the central axis of the drill bit body is arranged in the drill bit body, and the impact head is arranged such that one end thereof close to the working end of the drill bit body can exceed the range of the drill bit body during reciprocating movement.

[0009] In a preferred embodiment, the included angle between the movement axis of the impact head and the central axis of the drill bit body is in the range of 0-45 degrees.

[0010] In a preferred embodiment, the impact head is arranged in the drill bit body by means of eccentricity.

[0011] In a preferred embodiment, an impact mechanism is arranged in the channel of the drill bit body, and the impact mechanism is arranged to be able to respond to the mechanical energy of the drilling fluid flow in the channel to drive the punch to reciprocate.

[0012] In a preferred embodiment, the impact mechanism comprises:

[0013] An impeller is rotatably arranged in the channel, and the rotation axis of the impeller is perpendicular to the central axis of the channel;

[0014] A transmission rod is arranged, and two ends of the transmission rod are respectively connected with the impeller and the punch through hinging, and the hinging axis of the transmission rod is offset parallel to the rotation axis of the impeller.

[0015] In a preferred embodiment, the impact mechanism further comprises:

[0016] A guide block is fixedly arranged in the channel;

[0017] A sliding block is slidably arranged on the guide block, and one end of the sliding block is hinged with the transmission rod, and the other end of the sliding block is connected with the punch.

[0018] In a preferred embodiment, the impact mechanism further comprises a vertical connecting rod and a horizontal connecting rod, and the sliding block connects the punch through the vertical connecting rod and the horizontal connecting rod.

[0019] In a preferred embodiment, the distance between the rotation axis of the impeller and the moving track line of the sliding block ranges from 0 to 10 mm.

[0020] In a preferred embodiment, the moving track line of the punch is parallel to the central axis of the drill bit body, and the distance between the moving track line of the punch and the central axis of the drill bit body ranges from 0 to 2 / 3R, wherein R is the radius of the drill bit body.

[0021] In a preferred embodiment, the distance of the punch from the drill bit body during reciprocation ranges from greater than 0 to less than or equal to 5 mm.

[0022] Compared with the prior art, the application has the following advantages.

[0023] The impact mechanism is arranged in the drill bit body, the impact mechanism is a pure mechanical structure, the drilling fluid flows through the impeller to drive the impeller to rotate, the impeller drives the punch to reciprocate through the transmission rod, the energy transmission efficiency is high, the pressure is not needed to be built up, the damage to the drill bit body is reduced, and the service life of the drill bit is prolonged.

[0024] Meanwhile, the punch can exceed the range of the drill bit body and intermittently participate in scraping and cutting rock during reciprocating movement, further improving the rock breaking efficiency of the drill bit and solving the technical problem of low rock breaking efficiency of hard formation in deep well.

[0025] The punch forms vibration in the drill bit body, reduces the contact pressure between the drill bit and the wellbore, reduces the contact area between the wellbore and the well wall, thereby reducing the friction resistance between the wellbore and the well wall and reducing the possibility of pressure loss of the drill bit. BRIEF DESCRIPTION OF DRAWINGS

[0026] The application will be described below with reference to the drawings.

[0027] Figure 1 shows a schematic view of an embodiment of a PDC drill bit with impact function according to the application;

[0028] Figure 2 shows a perspective schematic view of an embodiment of an impact mechanism according to the application;

[0029] Figure 3 shows a side schematic view of an embodiment of an impact mechanism according to the application;

[0030] Figure 4 shows a schematic view of the distance of the punch exceeding the drill bit body according to the application;

[0031] Figure 5 shows a schematic view of the angle of the punch and the central axis of the drill bit body according to the application;

[0032] Figure 6 shows a structural schematic view of an impeller according to the application.

[0033] In the figure: 1, drill bit body; 11, channel; 12, blade; 13, cutting tooth; 14, main body; 2, punch; 21, impact tooth; 3, impact mechanism; 31, impeller; 311, impeller rotation shaft; 312, eccentric crank; 32, transmission rod; 33, guide block; 34, sliding block; 35, vertical connecting rod; 36, horizontal connecting rod; 37, first hinged shaft; 100, PDC drill bit with impact function.

[0034] In this application, all the drawings are schematic drawings, only for illustrating the principles of the application, and are not drawn in actual proportion. DETAILED DESCRIPTION

[0035] The application will be described below with reference to the drawings.

[0036] It should be noted that the directional phrases or limiting words "up", "down" and the like used in this application are all relative to the Figure 1And the like. They are not used to limit the absolute position of the parts involved, but can be changed according to the specific situation.

[0037] Figure 1 The structure of the PDC drill bit 100 with impact function according to the present application is shown. As Figure 1 shown, the PDC drill bit 100 with impact function includes a drill bit body 1, a channel 11 for the flow of drilling fluid is arranged inside the drill bit body 1.

[0038] In a specific embodiment, the drill bit body 1 includes a main body 14, a plurality of blades 12 are uniformly arranged on the lower end of the main body 14 in the circumferential direction, and a plurality of cutting teeth 13 are uniformly arranged on each blade 12, and the cutting teeth 13 are made of PDC material.

[0039] According to the present application, a punch 2 is arranged in the drill bit body 1 to move linearly and reciprocally at a certain angle with the central axis thereof, and the punch 2 is arranged such that the end close to the working end of the drill bit body 1 can exceed the range of the drill bit body 1 during reciprocating movement.

[0040] Through this arrangement, the impact generated by the PDC drill bit 100 with impact function directly acts on the rock-breaking punch 2, and the cutting teeth 13 are no longer subjected to impact load, reducing the probability of impact failure of the cutting teeth 13, and facilitating the extension of the service life of the PDC drill bit 100 with impact function.

[0041] Specifically, as Figure 5 shown, the angle between the movement axis of the punch 2 (the movement trajectory line of the punch 2) and the central axis of the drill bit body 1 is in the range of 0-45 degrees, that is, Figure 5 the angle a in the range of 0≤a≤45°.

[0042] The angle a is controlled within a certain range, so that the PDC drill bit 100 with impact function can impact and break the rock in each area of the drill bit, improve the diversity of drill bit design, and broaden the use range of the drill bit.

[0043] In a preferred embodiment, as Figure 1 and Figure 4 shown, the movement trajectory line of the punch 2 is parallel to the central axis of the drill bit body 1.

[0044] In a preferred embodiment, on the basis of the movement trajectory line of the punch 2 being parallel to the central axis of the drill bit body 1, the distance between the movement trajectory line of the punch 2 and the central axis of the drill bit body 1 is in the range of 0-2 / 3R.

[0045] Wherein, R refers to the radius of the drill bit body 1, and R specifically refers to the distance S from the radial edge of the blade 12 to the central axis of the main body 14. As Figure 4As shown, 0≤S≤2 / 3R.

[0046] Through the arrangement, the punch 2 is located at different radial positions of the drill bit body 1, the rock breaking efficiency of different regions of the drill bit can be improved, and in actual working process, personalized design can be performed according to specific drilling process and conditions, and the application range of the drill bit is widened.

[0047] In a preferred embodiment, the punch 2 is arranged in the drill bit body 1 in an eccentric manner, that is, the motion track of the punch 2 is away from the central axis of the drill bit body 1.

[0048] Further, the distance of the punch 2 from the drill bit body 1 during reciprocating motion is greater than 0 and less than or equal to 5 mm. In combination with the embodiment, as shown in Figure 4 As shown, the punch 2 further includes an impact tooth 21 arranged at the lower end, when the punch 2 moves to the lowermost end, the lowermost end of the impact tooth 21 is lower than the lowermost end of the cutting tooth 13, the distance between the lowermost end of the impact tooth 21 and the lowermost end of the cutting tooth 13 is set as M, and the value range of M is 0<M≤5 mm.

[0049] Through the arrangement, the lowermost position of the impact tooth 21 is intermittently lower than the cutting tooth 13 during the impact process, so that the impact tooth 21 breaks the rock by impact, and the cutting tooth 13 breaks the rock by scraping. And in the design of the drill bit, the relative position of the punch 2 and the cutting tooth 13 can be adjusted according to different lithology and drilling methods, so as to improve the adaptability of the PDC drill bit 100 with impact function to the formation and improve the rock breaking efficiency.

[0050] In a preferred embodiment, the impact tooth 21 is any one of a conical tooth, a wedge-shaped tooth, a spherical tooth or a combination of several thereof. Different types of impact teeth 21 are arranged on the punch 2, which can be suitable for different hardness formations, and provides an optional scheme for the selection of the PDC drill bit 100 with impact function.

[0051] Preferably, the position of the punch 2 extending out of the drill bit body 1 is within the arrangement range of the cutting tooth 13.

[0052] According to the present application, in a specific embodiment, the impact mechanism 3 is arranged in the channel 11 of the drill bit body 1, and the impact mechanism 3 is arranged to be able to respond to the mechanical energy of the drilling fluid flow in the channel 11 to drive the punch 2 to reciprocate.

[0053] In the embodiment, as shown in Figures 1-3 The impact mechanism 3 includes an impeller 31 arranged in the channel 11 in a rotating manner, and the rotation axis of the impeller 31 is perpendicular to the central axis of the channel 11.

[0054] As shown in Figure 6As shown, the two impellers 31 are configured as a left-right symmetrical structure, and an eccentric crank 312 is eccentrically arranged between the two left-right symmetrical impellers 31. That is, the two impellers 31 in this embodiment rotate synchronously under the fixed connection of the eccentric crank 312. An impeller rotation shaft 311 is provided at the central axis of the ends of the two impellers 31 that are far away from each other.

[0055] The impeller 31 is rotatably mounted inside the drill bit body 1 via the impeller rotating shaft 311 and is located in the channel 11. The central axis of the impeller rotating shaft 311 is perpendicular to the central axis of the drill bit body 1. When the drilling fluid flows in the channel 11, the impeller 31 can rotate continuously under the push of the drilling fluid.

[0056] The central axis of the eccentric crank 312 is parallel to the central axis of the impeller 31, and the central axis of the eccentric crank 312 does not coincide with the central axis of the impeller 31. A transmission rod 32 is provided on the eccentric crank 312 by means of hinge, and the lower end of the transmission rod 32 is connected to the punch 2.

[0057] With this configuration, when the impeller 31 rotates continuously under the action of drilling fluid, the impeller 31 drives the transmission rod 32 to move up and down repeatedly through the eccentric crank 312, which in turn drives the punch 2 to move up and down repeatedly.

[0058] Furthermore, the impact mechanism 3 also includes a guide block 33 and a slider 34.

[0059] The guide block 33 is fixedly installed inside the drill body 1 and the foreign language channel 11. The length direction of the guide block 33 is parallel to the movement trajectory of the punch 2.

[0060] The slider 34 is slidably mounted on the guide block 33, and the direction of movement of the slider 34 is parallel to the movement trajectory of the punch 2. One end of the slider 34 is hinged to the transmission rod 32 via the first hinge shaft 37, and the other end is connected to the punch 2.

[0061] By setting guide block 33 and slider 34, the reciprocating movement of punch 2 is guided, making the movement of punch 2 smoother.

[0062] In a preferred embodiment, the impact mechanism 3 further includes a vertical connecting rod 35 and a horizontal connecting rod 36, and the slider 34 is connected to the punch 2 through the vertical connecting rod 35 and the horizontal connecting rod 36.

[0063] like Figure 1 As shown, the vertical connecting rod 35 is coaxially fixed at the lower end of the slider 34, and the horizontal connecting rod 36 is fixedly fixed at the lower end of the vertical connecting rod 35. The end of the horizontal connecting rod 36 away from the vertical connecting rod 35 is fixedly connected to the punch 2.

[0064] It is easy to understand that a space for the movement of the horizontal connecting rod 36 and the vertical connecting rod 35 is provided in the drill bit body 1, and the space for the movement of the horizontal connecting rod 36 and the vertical connecting rod 35 in the drill bit body 1 is not limited to Figure 1 as shown.

[0065] In the present embodiment, the distance between the rotation axis of the impeller 31 and the movement trajectory line of the slider 34 ranges from 0 to 10 mm. As shown, Figure 3 the straight line parallel to the slider 34 and intersecting the central axis of the first hinged shaft 37 is defined as the movement trajectory line of the slider 34, and the distance between the rotation axis of the impeller 31 and the movement trajectory line of the slider 34 is defined as H, 0≤H≤10 mm.

[0066] In a preferred embodiment, the central axis of the impeller 31 and the movement trajectory line of the slider 34 coincide with each other. That is, the distance H between the rotation axis of the impeller 31 and the movement trajectory line of the slider 34 is 0.

[0067] When H=0, the impact generated by the impact mechanism 3 is relatively uniform, forming a certain frequency of vibration, which can not only break rocks but also protect the cutting teeth 13, improve the service life of the PDC drill bit 100 with impact function, and reduce the wrapping force and friction force between the PDC drill bit 100 with impact function and the well wall, thereby reducing the occurrence of drill bit pressure loss.

[0068] In another preferred embodiment, the central axis of the impeller 31 and the movement trajectory line of the slider 34 do not coincide. That is, the distance H between the central axis of the impeller 31 and the movement trajectory line of the slider 34 ranges from 0 to 10 mm.

[0069] Through such arrangement, the impact mechanism 3 with eccentricity is formed, the speed of the slider 34 during impact and return is inconsistent, the distance between the central axis of the impeller 31 and the movement trajectory line of the slider 34 is controlled within the range of the present embodiment, the impact speed of the slider 34 is larger, the impact work of the PDC drill bit 100 with impact function is improved, and the rock breaking efficiency of the PDC drill bit 100 with impact function is improved.

[0070] According to the present application, when the PDC drill bit 100 with impact function is working downhole, the drilling fluid drives the impeller 31 to rotate at high speed, the impeller 31 drives the eccentric crank 312 to rotate at high speed, and further drives the transmission rod 32 to move up and down, forming a typical crank connecting rod mechanism.

[0071] At this time, the slider 34 generates vertical up and down movement under the constraint of the guide block 33, drives the vertical connecting rod 35 and the horizontal connecting rod 36 to generate up and down movement, and the horizontal connecting rod 36 drives the punch 2 to reciprocate in the blade 12. Further, the punch 2 is parallel to the central axis of the drill bit body 1, and can generate vertical up and down impact movement, and when the punch 2 is at a certain angle with the central axis of the drill bit body 1, can generate oblique up and down impact movement, thereby driving the impact teeth 21 to intermittently participate in breaking the stratum.

[0072] According to the present application, the PDC drill bit 100 with the impact function generates impact of a certain frequency in the drill bit body 1 by the impact mechanism 3, the present application is a pure mechanical transmission structure, the energy transmission efficiency is high, the pressure is not stored, the damage to the drill string and the drill bit is reduced, and the service life of the drill bit is prolonged.

[0073] The present application breaks the rock by the energy of the drilling fluid, thereby improving the use rate of the drilling fluid energy, and the PDC drill bit 100 with the impact function breaks the well bottom by the impact-scraping mixed mode, thereby improving the drilling efficiency of the drill bit.

[0074] The present application provides impact by the punch 2, avoids that the cutting tooth 13 directly bears impact, can effectively break the rock, and avoids impact failure of the cutting tooth 13, thereby improving the service life of the PDC drill bit 100 with the impact function.

[0075] In the description of the present application, it should be understood that the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "a plurality of" is two or more, unless otherwise specifically limited.

[0076] In the present application, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, can be fixedly connected, can be detachably connected, or integrally connected, can be mechanically connected, or electrically connected, can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements. For ordinary skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0077] In the description of the specification, the description of the terms "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are contained in at least one embodiment or example of the present application. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples.

[0078] Finally, it should be noted that the above only describes the preferred embodiments of the present application and does not constitute any limitation on the present application. Although the present application is described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments or make equivalent replacements to some technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A PDC bit with impact function, comprising a bit body (1), a channel (11) for drilling fluid flow is arranged in the interior of the bit body (1), characterized in that, a punch (2) is arranged in the bit body (1) to move linearly and reciprocally at a certain angle with the central axis thereof, the punch (2) is arranged to be able to exceed the range of the bit body (1) in the process of reciprocating motion at the end close to the working end of the bit body (1), an impact mechanism (3) is arranged in the channel (11) of the bit body (1), the impact mechanism (3) is arranged to be able to drive the punch (2) to reciprocate in response to the mechanical energy of the drilling fluid flow in the channel (11), the impact mechanism (3) comprises: an impeller (31) is arranged in the channel (11) in a rotating manner, the rotation axis of the impeller (31) is perpendicular to the central axis of the channel (11); a transmission rod (32), both ends of the transmission rod (32) are connected with the impeller (31) and the punch (2) by hinged manner respectively, the hinged axis of the transmission rod (32) and the impeller (31) is offset parallel to the rotation axis of the impeller (31); a guide block (33) is fixedly arranged in the channel (11); a sliding block (34) is slidingly arranged on the guide block (33), one end of the sliding block (34) is hinged with the transmission rod (32), the other end is connected with the punch (2), the central axis of the impeller does not coincide with the moving track line of the sliding block, forming an impact mechanism with eccentricity.

2. The PDC bit having an impact function according to claim 1, characterized by, The included angle between the movement axis of the punch (2) and the central axis of the bit body (1) is in the range of 0-45 degrees.

3. The PDC bit having an impact function according to claim 1, wherein, The punch (2) is arranged in the bit body (1) in an eccentric manner.

4. The PDC bit having an impact function according to any one of claims 1 to 3, characterized by, The impact mechanism (3) further comprises a vertical connecting rod (35) and a horizontal connecting rod (36), the sliding block (34) connects the punch (2) through the vertical connecting rod (35) and the horizontal connecting rod (36).

5. The PDC bit having an impact function according to any one of claims 1 to 3, characterized by, The distance between the rotation axis of the impeller (31) and the moving track line of the sliding block (34) is in the range of 0-10 mm.

6. The PDC bit having a ballistic function according to claim 1, wherein, The moving track line of the punch (2) is parallel to the central axis of the bit body (1), the distance between the moving track line of the punch (2) and the central axis of the bit body (1) is in the range of 0-2 / 3R, wherein R is the radius of the bit body (1).

7. The PDC bit having a ballistic function according to claim 1, wherein, The distance of the punch (2) exceeding the bit body (1) in the process of reciprocating motion is greater than 0 and less than or equal to 5 mm.

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