A composite plate for a drill bit

Abstract

The utility model belongs to the technical field of mining drill bit, concretely relates to a drill bit is with buckling composite sheet, including coring drill bit main part and its installation seat on installation, is installed with the composite sheet main body on the installation seat, still include: the outer periphery of composite sheet main body forms the buckling of buckling in the direction of chip removal and goes out a section, wherein, the recess and the aperture are equipped on the composite sheet main body, the recess extends from the outer periphery to the center of composite sheet main body, the aperture is set up in the vicinity of the outer edge of buckling, and the aperture is communicated with the recess. The upper surface edge of composite sheet main body is equipped with the chamfer edge, and the chamfer edge is the circular arc chamfer. In work, the chamfer edge can weaken the blade stress concentration, and restrain the micro collapse. The utility model sets up the buckling on the outer edge of composite sheet, makes the drilling process can complete the primary crushing and cut in fast, and will the new rock debris from the hole wall lift away after directional collection to the recess entrance, then the aperture and drill bit main ejection groove continuous communication discharge, avoid the outer edge to stay and jammed angle, reduce backfill and secondary cutting.

Description

Technical Field

[0001] This utility model belongs to the field of mining drill bit technology, specifically relating to a drill bit edge-curving composite sheet. Background Technology

[0002] In resource development fields such as geological exploration, oil and gas drilling, and mining, coring bits are the core tools for obtaining underground rock cores (rock samples). Composite sections, as key cutting components of coring bits, directly determine drilling efficiency, core quality, and service life through their structural design. As exploration and development advance into deeper and more complex formations (such as hard formations, formations with well-developed joints and fractures, and formations containing thin interlayers), it is necessary to meet the requirements for cutting and cuttings removal.

[0003] However, in long-term continuous drilling operations such as geological exploration, oil and gas drilling, and mining, existing solutions still have the following common problems and shortcomings: Initial entry into hard interlayers is difficult: For composite sheets with flat end faces or only grooved end faces, the initial contact is mostly surface contact or a large contact band, which is easy to slip on dense, brittle and hard interlayers, making it difficult for cracks to establish quickly and affecting the cutting efficiency. In addition, multiple convex corners are set on the outer edge to increase the number of contact points, but this will disperse the load, weaken the single-point cutting force, and form multiple friction tracks and gaps during rotation, which can easily lead to dead corners of rock cuttings. Multiple convex corners cause stress concentration at geometric angles, increase processing difficulty and scrap rate, and require inspection and repair after service, increasing maintenance costs and downtime. In summary, existing technologies generally lack a method for achieving rapid cutting into a composite structure at the outer edge, which can stably connect to the main chip flute of the drill bit, while also considering the economics of manufacturing and maintenance, and avoiding the problems of force distribution, dead angles, yield rate, and repair complexity caused by multi-convex angle structures. Utility Model Content

[0004] The purpose of this invention is to provide a composite chip for drill bits with raised edges. The raised edges enable rapid initial crushing and cutting during drilling, and the newly formed rock cuttings are lifted from the borehole wall and oriented and collected to the groove entrance. They are then continuously discharged through the notch and the main chip removal groove of the drill bit, avoiding the retention of outer edges and dead corners, and reducing backfilling and secondary cutting.

[0005] The specific technical solution adopted by this utility model is as follows: A composite sheet for drill bits includes a core drill bit body and a mounting base mounted thereon, wherein the composite sheet body is mounted on the mounting base; Also includes: A section of the outer periphery of the composite sheet body has a raised edge that curves upwards towards the direction of chip removal; The composite sheet body has a groove and a notch. The groove extends from the outer periphery to the center of the composite sheet body, and the notch is opened near the outer edge of the raised edge, and the notch is connected to the groove.

[0006] Preferably, the upper surface edge of the composite sheet body is provided with a chamfered edge, and the chamfered edge is a rounded chamfer.

[0007] By adopting the above solution, during operation, the chamfered edge can reduce the stress concentration at the cutting edge, suppress micro-chipping, and improve the service life of the composite sheet body.

[0008] Preferably, the upper surface of the warped edge is provided with a protrusion, and the protrusion forms a wedge-shaped edge in the thickness direction.

[0009] Using the above scheme, during operation, the protrusion can induce microcracks more quickly and push rock cuttings into the near-side groove. The periodic cutting and pulsating shearing can further break up the retained rock cuttings, which helps to maintain the unobstructed passage. Preferably, there are two grooves and two notches, and the two grooves and two notches are symmetrically arranged along the main body of the composite sheet.

[0010] With the above scheme, during operation, the two grooves and two notches are set up. Rock cuttings will preferentially enter the grooves on the near side after rotation. The rock cuttings entering the grooves will migrate stably under the coupling effect of centrifugal force, flushing flow and groove wall friction. The two grooves establish a dual-channel spiral migration line, reducing local accumulation and secondary cutting. Preferably, both notches are positioned facing the main chip removal groove of the core drill bit body.

[0011] By adopting the above scheme, during operation, rock cuttings are promptly released to the outer edge of the composite sheet after reaching the opening on the outer periphery, thus preventing dead corners from getting stuck at the outer edge. Preferably, the bottom surface of the curled edge is provided with a slope, and the inner side of the curled edge is provided with a thickened strip.

[0012] With the above solution, during operation, the thickened strip bears the root bending moment and impact, reducing peeling and interface damage. After overall wear, the warped working surface tends to form a more stable front angle shape, and the cutting state is more durable. The technical effects achieved by this utility model are as follows: This invention features a raised edge on the outer edge of the composite sheet, which allows for rapid initial crushing and cutting during drilling. It also lifts newly formed rock cuttings from the borehole wall and directs them to the groove entrance, where they are then continuously discharged through the notch and the main chip removal groove of the drill bit. This avoids stagnation and dead angles on the outer edge, and reduces backfilling and secondary cutting. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a top view of the present invention; Figure 3 This is a schematic diagram of the composite sheet body and the core drill bit body in this utility model.

[0014] The attached diagram lists the components represented by each number as follows: 1. Composite sheet body; 2. Curved edge; 3. Groove; 4. Notch; 5. Protrusion; 6. Chamfered edge; 7. Mounting base; 8. Core drill bit body. Detailed Implementation

[0015] To make the objectives and advantages of this utility model clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the following text is merely used to describe one or more specific embodiments of this utility model and does not strictly limit the scope of protection specifically claimed by this utility model.

[0016] like Figure 1-3 As shown, a composite sheet for drill bits includes a core drill bit body 8 and a mounting base 7 mounted thereon, with the composite sheet body 1 mounted on the mounting base 7; The aforementioned mounting base 7, core drill bit body 8, and composite sheet body 1 are all existing mature technologies, and will not be described in detail in this embodiment. The core solution of this technical solution lies in the specific structure of the composite sheet body 1.

[0017] The outer periphery of the composite sheet body 1 is formed with a curved edge 2 that curves upward in the direction of chip removal, which is used to achieve outer edge wedging during drilling; The composite sheet body 1 is provided with a groove 3 and a notch 4. During assembly, the notch 4 is preferably set towards the main chip removal groove of the core drill bit body 8. The groove 3 extends towards the center of the composite sheet body 1. The notch 4 is opened near the outer edge of the raised edge 2 and is connected to the groove 3 to form a chip removal channel from the outer edge cutting edge to the outer periphery. When using: When the core drill bit body 8 rotates and is fed axially, the effective wedge angle formed by the raised edge 2 of the outer periphery of the composite plate body 1 first contacts the rock surface, generating tensile-shear composite stress on the hole wall. Initial cracks are formed on the outer edge and a line contact-surface expansion crushing process occurs, completing the initial crushing and cutting of the target rock layer. As the drill bit rotates and advances, the rock cuttings are quickly lifted off the borehole wall on the inclined surface of the raised edge 2, and are directionally collected along the transition area between the inclined surface and the end face of the composite piece to the entrance position of the groove 3, avoiding backfilling or accumulation at the outer edge; Under the action of centrifugal force and flushing flow, the rock cuttings entering the groove 3 continue to migrate outward along the bottom of the groove 3; After the cuttings reach the notch 4 on the outer periphery, they are promptly discharged to the outer edge of the composite plate. When assembled into the drill bit, the notch 4 and the main chip discharge groove of the drill bit body 8 are naturally connected and merged in space. The cuttings are carried out of the cutting zone by the flushing flow, suppressing the dead corner of the outer edge. If local rock cuttings remain in the vicinity of groove 3 for a short time, the periodic pressure difference caused by rotation and the shear flow in the groove will cause secondary disturbance and retransport, maintaining the self-cleaning state of the guide-discharge channel. The raised edge 2 quickly detaches the newly formed rock cuttings from the borehole wall and guides them into the groove 3, significantly reducing the peak value of lateral extrusion on the borehole wall, reducing backfilling and repeated cutting, thus resulting in smaller torque fluctuations, lower risk of jamming, and helping to maintain the integrity of the core and borehole wall; This invention features a raised edge 2 on the outer edge of the composite sheet, which allows for rapid initial crushing and cutting during drilling. The newly formed rock cuttings are lifted from the borehole wall and oriented to the inlet of the groove 3, and then continuously discharged through the notch 4 and the main chip removal groove of the drill bit. This avoids stagnation and dead angles on the outer edge, and reduces backfilling and secondary cutting.

[0018] Compared with flat end faces without warping or only slotted end faces, this solution allows for faster cutting, smoother chip removal, and smaller torque fluctuations, which can significantly reduce lateral extrusion and abrasion of the borehole wall and improve the integrity of the core. Meanwhile, the stable guide-chip removal link, combined with the self-cleaning effect formed by the rotating pressure difference and the sliding flow in the groove, brings better thermal management and anti-adhesion performance, and is more robust to assembly angle and working condition fluctuations, thereby improving continuous operation efficiency and extending the overall machine life. See attached document Figure 1 and attached Figure 2 In addition, a protrusion 5 is provided on the top of the warped edge 2. The protrusion 5 is located on the upper surface of the composite sheet body 1 and forms a wedge-shaped blade in the thickness direction. The initial contact of the protrusion 5 is a small-area single-point strong incision, which can induce microcracks more quickly and push rock fragments into the near-side groove 3. The periodic incision and the pulsating shearing can further break up the retained rock fragments, which helps to maintain the smooth flow of the channel. See attached document Figure 2 The upper surface edge of the composite sheet body 1 is provided with a chamfered edge 6, which is a rounded chamfer. When in use: the chamfered edge 6 can reduce stress concentration on the cutting edge and suppress micro-chipping; In terms of quantity, there are two grooves 3 and two notches 4, and the two grooves 3 and the two notches 4 are symmetrically arranged along the composite sheet body 1, and the two notches 4 are both facing the main chip removal groove of the core drill bit body 8. Due to the arrangement of two grooves 3 and two openings 4, the rock cuttings will preferentially enter the nearby groove 3 after rotation. Under the coupling effect of centrifugal force, flushing flow and groove wall friction, the rock cuttings entering the groove 3 will migrate stably along the sliding channel formed by the bottom and wall of the groove. The two symmetrical grooves 3 establish a double-channel spiral migration line, reducing local accumulation and secondary cutting. See attached document Figure 1 The bottom surface of the curved edge 2 is set with a slope to form a stable gap for chip release and flow guidance between the main body 1 of the composite sheet and the flow channel, thereby reducing the short-term accumulation and backfilling of rock chips at the outer edge. A thickened strip is provided on the inner side of the warped edge 2. The thickened strip bears the root bending moment and impact, reduces peeling and interface damage. After overall wear, the working surface of the warped edge 2 tends to form a more stable rake angle shape, and the cutting state is more durable. The above description is merely a preferred embodiment of this utility model. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of this utility model, and these improvements and modifications should also be considered within the scope of protection of this utility model. Structures, devices, and operating methods not specifically described or explained in this utility model, unless otherwise specified or limited, shall be implemented using conventional methods in the field.

Claims

1. A composite sheet for drill bits, comprising a core drill bit body (8) and a mounting base (7) mounted thereon, wherein the composite sheet body (1) is mounted on the mounting base (7). Its features are, Also includes: The outer periphery of the composite sheet body (1) has a raised edge (2) that curves upward toward the direction of chip discharge. The composite sheet body (1) is provided with a groove (3) and a notch (4). The groove (3) extends from the outer periphery to the center of the composite sheet body (1). The notch (4) is opened near the outer edge of the raised edge (2), and the notch (4) is connected to the groove (3).

2. The drill bit edge-lifting composite sheet according to claim 1, characterized in that: The upper surface edge of the composite sheet body (1) is provided with a chamfered edge (6), and the chamfered edge (6) is a rounded chamfer.

3. The drill bit edge-trimming composite sheet according to claim 1, characterized in that: The upper surface of the raised edge (2) is provided with a protrusion (5), and the protrusion (5) forms a wedge-shaped edge in the thickness direction.

4. The drill bit edge-lifting composite sheet according to claim 1, characterized in that: The number of grooves (3) and notches (4) are both two, and the two grooves (3) and the two notches (4) are symmetrically arranged along the composite sheet body (1).

5. The drill bit edge-lifting composite sheet according to claim 1, characterized in that: Both of the notches (4) are set toward the main chip removal groove of the core drill bit body (8).

6. The drill bit edge-lifting composite sheet according to claim 1, characterized in that: The bottom surface of the curved edge (2) is provided with a slope, and the inner side of the curved edge (2) is provided with a thickened strip.

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