Multi-edge PDC (Polycrystalline Diamond Compact) cutting tooth suitable for hard plastic stratum

Abstract

The utility model relates to the technical field of well drilling, in particular to a multi-edge PDC (Polycrystalline Diamond Compact) cutting tooth suitable for a hard plastic stratum, which comprises a support body and a cutting body arranged at the top of the support body, the cutting body comprises a prismatic bulge; the cross section of the cutting body is circular, and the multiple prismatic protrusions are distributed on the face, away from the supporting body, of the cutting body at equal intervals with the circle center as the center and converge at the circle center to form a cutting tooth center. According to the utility model, the cutting efficiency and performance in a hard plastic stratum are obviously improved; due to the edge-shaped bulges which are radially arranged at equal intervals, the cutting force and the crushing capacity of the cutting teeth are enhanced, the distribution of the cutting force is optimized, and the cutting resistance and the abrasion are reduced, so that the service life of the cutting teeth is prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of drilling, in particular to a multi-edge PDC cutting tooth suitable for hard plastic formations. Background Art

[0002] With the continuous deepening of global energy resource exploration and development, especially in the exploration of energy fields such as oil, natural gas and geothermal energy, drilling technology faces unprecedented challenges. As drilling operations advance to deeper formations, some well sections encounter high-pressure environments, and the well structure becomes increasingly complex, including the widespread application of directional wells and horizontal wells, which puts higher requirements on the performance of drilling fluids. In order to effectively deal with well control problems and prevent wellbore instability, the specific gravity of the drilling fluid is forced to increase, which leads to a significant increase in the liquid column pressure in the well. As the burial depth of the formation increases, the hardness of the rock increases sharply, especially soft rocks such as mudstone and shale. Under the combined action of high-density drilling fluid and high liquid column pressure, they show significant plastic characteristics, forming a hard-plastic effect in medium and deep formations. This geological characteristic has a significant impact on mechanical drilling operations: the composite pieces of traditional PDC drill bits (polycrystalline diamond composite pieces drill bits) are difficult to effectively embed in hard plastic formations, resulting in low cutting efficiency, large-sized cuttings, and the drilling fluid is difficult to effectively carry the cuttings away from the bottom of the well, resulting in repeated cutting of cuttings and increased wear of the drill bit. At the same time, the formation's abrasive effect on the composite piece is enhanced, further shortening the service life of the drill bit, increasing the contact area between the drill bit and the formation, and increasing the difficulty of cutting, ultimately leading to a significant decrease in mechanical drilling speed and an extension of the drilling cycle, which not only affects operational efficiency and safety, but also significantly increases operating costs. Utility Model Content

[0003] The purpose of the utility model is to provide a multi-edge PDC cutting tooth suitable for hard plastic formations in order to solve at least one of the above technical problems.

[0004] The utility model achieves the above-mentioned purpose through the following technical solutions:

[0005] A multi-edge PDC cutting tooth suitable for hard plastic formations, comprising a support body, a cutting body arranged on the top of the support body;

[0006] The cutting body includes a prismatic protrusion;

[0007] The cross section of the cutting body is circular, and a plurality of prismatic protrusions are distributed at equal intervals on a side of the cutting body away from the supporting body with the center of the circle as the center, and converge at the center of the circle to form a cutting tooth center.

[0008] Furthermore, the protrusions of the ridge-shaped protrusions are provided with arc-shaped chamfers.

[0009] Further, the angle between the two rib-like protrusions forms a depression on the surface of the cutting body.

[0010] Further, the number of the rib-like protrusions is six.

[0011] Further, the support body is a cylinder.

[0012] Further, the distance between the rib-like protrusion and the edge of the cutting body is half of the radius of the circular cross-section of the cutting body.

[0013] The beneficial effects of the present utility model are as follows:

[0014] By designing a circular PDC cutting tooth with multiple rib-like protrusions, the present utility model significantly enhances the cutting ability of the cutting tooth for hard plastic formations. Each rib-like protrusion can cut the formation independently. When one rib wears, the remaining ribs can continue to cut effectively, improving the durability and mechanical drilling rate of the drill bit. The depression between the rib-like protrusions promotes the rapid discharge of cuttings, reduces repeated cutting, and improves the drilling efficiency.

[0015] Aiming at the drilling problems in hard plastic formations, the multi-rib PDC cutting tooth provided by the present utility model effectively reduces the cutting resistance and stress concentration through its unique multi-rib structure and arc chamfer design, improving the cutting efficiency and the service life of the cutting tooth. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is an overall schematic diagram of a multi-rib PDC cutting tooth applicable to hard plastic formations according to an embodiment of the present utility model;

[0017] Figure 2 It is a top view of a multi-rib PDC cutting tooth applicable to hard plastic formations according to an embodiment of the present utility model;

[0018] Figure 3 It is a side view of a multi-rib PDC cutting tooth applicable to hard plastic formations according to an embodiment of the present utility model.

[0019] In the figure: 1, support body; 2, cutting body; 21, rib-like protrusion; 22, arc chamfer; 23, cutting tooth center. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0020] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all of the embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present utility model.

[0021] Embodiment 1

[0022] Figure 1 It is an overall schematic diagram of a multi - edged PDC cutting tooth applicable to a hard - plastic formation according to an embodiment of the present utility model; Figure 2 It is a top view of a multi - edged PDC cutting tooth applicable to a hard - plastic formation according to an embodiment of the present utility model; Figure 3 It is a side view of a multi - edged PDC cutting tooth applicable to a hard - plastic formation according to an embodiment of the present utility model. As Figures 1-3 shown, according to an embodiment of the present utility model, a multi - edged PDC cutting tooth applicable to a hard - plastic formation includes a support body 1 and a cutting body 2 arranged on the top of the support body 1;

[0023] The cutting body 2 includes prismatic protrusions 21;

[0024] The cross - section of the cutting body 2 is circular, and a plurality of prismatic protrusions 21 are equally spaced around the center of the circle on the side of the cutting body 2 facing away from the support body 1 and converge at the center of the circle to form a cutting tooth center 23.

[0025] Preferably, the number of the prismatic protrusions 21 is 6.

[0026] In this embodiment, the multi - edged PDC (polycrystalline diamond compact) cutting tooth is applicable to a hard - plastic formation. The support body 1 serves as the basic structure of the entire cutting tooth, stably carrying the upper - placed cutting body 2 to ensure a stable cutting attitude during high - speed rotation and deep drilling. The cross - section of the cutting body 2 is circular, which not only enhances the structural stability but also makes the cutting force distribution more uniform. On the side of the cutting body 2 facing away from the support body 1, a plurality of prismatic protrusions 21 are provided. These prismatic protrusions 21 are arranged in an equally - spaced radial pattern around the center of the circle and finally converge at the center of the circle to form the cutting tooth center 23. Such a layout enables each prismatic protrusion 21 to act independently and cooperatively on the formation. Through its sharp edges and tips, it can effectively cut into the hard - plastic formation to achieve efficient cutting. During the drilling process, as the cutting tooth rotates, the prismatic protrusions 21 continuously scrape and break the formation material. At the same time, their special geometric shape can effectively disperse the cutting force, reduce the cutting resistance and wear, and improve the drilling efficiency and the service life of the cutting tooth.

[0027] The present utility model significantly improves the cutting efficiency and performance in a hard - plastic formation; its equally - spaced radial - arranged prismatic protrusions not only enhance the cutting force and crushing ability of the cutting tooth but also optimize the cutting force distribution, reduce the cutting resistance and wear, thereby prolonging the service life of the cutting tooth. The structure of the present utility model is stable and has strong adaptability, and can maintain an efficient cutting effect in a complex drilling environment, providing strong technical support for the drilling operation of hard - plastic formations.

[0028] According to an embodiment of the present utility model, an arc chamfer 22 is provided at the protruding part of the prismatic protrusion 21.

[0029] In this embodiment, the arc chamfer 22 of the prismatic protrusion 21 plays a key role in the cutting process. When the cutting tooth rotates and contacts the hard plastic formation, the sharp edge of the prismatic protrusion 21 first contacts the formation and starts cutting. At this time, the design of the arc chamfer 22 makes the contact surface during the cutting process no longer a sharp right angle, but a smooth arc. This smooth transition reduces the direct impact and stress concentration between the cutting tooth and the formation during cutting, thereby reducing the cutting resistance. The arc chamfer also reduces the friction area between the cutting tooth and the formation, and this reduced contact area further reduces the friction and wear during the cutting process, extending the service life of the cutting tooth. The arc chamfer 22 also helps to guide the chips and particles generated by cutting to smoothly discharge along the surface of the cutting tooth, reducing the chip accumulation phenomenon during cutting and improving the continuity and stability of cutting.

[0030] The arc chamfer design of the prismatic protrusion of the present utility model effectively reduces the cutting resistance and wear, and further improves the cutting efficiency and the durability of the cutting tooth.

[0031] According to an embodiment of the present utility model, the angle between two prismatic protrusions 21 forms a depression on the surface of the cutting body 2.

[0032] In this embodiment, a depression is formed at the angle between two prismatic protrusions 21, and this design plays multiple positive roles in the cutting process. First of all, the existence of the depression provides a natural chip discharge channel for the chips and particles generated during the cutting process. When the cutting tooth rotates and cuts the formation, the generated chips tend to flow along the surface of the cutting tooth, and the depression serves as a collection and guiding area for these chips, helping them to be discharged smoothly from the cutting area, reducing the chip accumulation phenomenon on the cutting surface. Secondly, the design of the depression also helps to reduce the resistance during the cutting process. Due to the existence of the depression, the contact area between the cutting tooth and the formation is locally reduced, especially in the area between the two prismatic protrusions. This reduced contact area reduces the frictional resistance between the cutting tooth and the formation during cutting, making the cutting process smoother, thereby improving the cutting efficiency. In addition, the depression can also have a positive impact on the distribution of the cutting force. During the cutting process, the cutting force is distributed along the surface of the cutting tooth, and the design of the depression helps to more evenly disperse the cutting force to each prismatic protrusion, reducing the phenomenon of local stress concentration and improving the overall stability and durability of the cutting tooth.

[0033] The angle between the two prismatic protrusions of the present utility model forms a depression, which helps to discharge chips and reduce the resistance during the cutting process, improving the cutting efficiency.

[0034] According to one embodiment of the present invention, the support body 1 is a cylinder.

[0035] In this embodiment, the support body 1 is designed as a cylinder, mainly based on its high structural stability, good rotational balance, convenient processing and compliance with standardization requirements, which can ensure efficient and stable cutting of the cutting teeth under complex geological conditions.

[0036] The utility model effectively improves the cutting efficiency and durability of the cutting teeth, reduces energy consumption and costs, and enhances the reliability and economic benefits of drilling operations.

[0037] According to an embodiment of the present invention, the distance between the prismatic protrusion 21 and the edge of the cutting body 2 is 1 / 2 of the radius of the circular cross-section of the cutting body 2 .

[0038] In this embodiment, the distance between the prismatic protrusion 21 and the edge of the cutting body is 1 / 2 of the radius of the circular section of the cutting body 2, which ensures that when the cutting teeth contact the hard plastic formation, the prismatic protrusion can serve as the main cutting point, and effectively cut into the formation with its sharp wedge-shaped structure, thereby improving the cutting efficiency and penetration. The rock chips generated during the cutting process will flow to both sides along the surface of the cutting teeth, and the position setting of the protrusion just provides a smooth discharge channel for the rock chips, reducing the accumulation of rock chips on the cutting surface and the possibility of repeated cutting.

[0039] The utility model improves the cutting efficiency and stability of the cutting teeth in hard plastic formations and simultaneously promotes the rapid discharge of rock cuttings.

[0040] The utility model can cope with complex formations such as mudstone, shale, muddy siltstone, and silty mudstone with large burial depths. These formations show significant hard-plastic characteristics due to the high pressure of the drilling fluid column, which poses a significant wear challenge to the drill bit. In such formations, once the traditional circular composite drill bit encounters slight wear, it is difficult to effectively cut into the formation, resulting in a significant decrease in the mechanical drilling speed.

[0041] Compared with conventional designs, the utility model adopts a hexagonal raised composite sheet structure, and its sharp edge shape significantly enhances the cutting ability of hard plastic formations. When one edge of the drill bit is slightly damaged due to contact with hard formations, the edges on its left and right sides will automatically take over and continue to cut the formation efficiently. This mechanism not only effectively protects the damaged edges, but also significantly improves the overall cutting efficiency through the synergistic effect of multiple edges.

[0042] The design of the hexagonal protrusions of the utility model enables the strip-shaped rock cuttings formed during the cutting process to be further refined and broken into smaller particles. This change greatly promotes the suspension and carrying of the rock cuttings in the drilling fluid, and effectively prevents the "holding" phenomenon of the rock cuttings at the bottom of the well under high liquid column pressure, thereby avoiding the problem of repeated cutting and significantly improving the efficiency and safety of drilling operations.

[0043] Embodiment 2

[0044] As Figures 1-3 shown, according to an embodiment of the present utility model, a hexagonal PDC cutting tooth applicable to a hard plastic formation, the part of the hexagonal PDC cutting tooth facing the formation is a prismatic protrusion 21, the surface of the cutting tooth is recessed inside, and the wedge-shaped protrusion part is arc-shaped;

[0045] The protruding part of the front prismatic cutting tooth in contact with the formation is arc-shaped;

[0046] The cutting method of the front prismatic cutting tooth is that the prismatic protrusion 21 contacts the formation, and the prism tip is facing the cuttings for cutting;

[0047] The prismatic protrusions 21 are evenly distributed at six equal parts on the edge of the circular cutting tooth;

[0048] Compared with the conventional circular composite sheet, the cutting ability of the sharp edge to the hard plastic formation is stronger. When one edge facing the formation is slightly damaged by the hard formation, the left and right edges will participate in the cutting of the formation, which can protect the first edge and increase the cutting ability to the formation.

[0049] When the formation is cut into cuttings by one edge facing the formation by the hexagonal PDC cutting tooth, the cuttings will be further broken and crushed by several other edges, becoming cuttings with smaller volume, which is beneficial to the cuttings being quickly carried away from the bottom of the well by the drilling fluid and preventing the problem of repeated cutting due to the cuttings being "held down" at the bottom of the well by the high liquid column pressure.

[0050] In an environment with high drilling fluid specific gravity and high drilling fluid column pressure, the sharp edge of the drill bit using the present utility model can penetrate deep into the hard plastic mudstone and shale. After the main edge is worn by the formation, the left and right edges can participate in cutting the formation, improving the effective service life of the composite sheet. The setting of the six edges can fully break the shape of the cuttings, making it less likely to form balls, thereby reducing the "holding-down effect" of the cuttings and increasing the drilling rate of penetration.

[0051] For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above exemplary embodiments, and can be implemented in other specific forms without departing from the spirit or basic characteristics of the present utility model. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present utility model. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0052] In addition, it should be understood that although this specification is described in terms of embodiments, not every embodiment contains only an independent technical solution. This narrative manner of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A multi-edge PDC cutting tooth applicable to hard plastic formations, comprising a support body (1), characterized in that, Further comprising: A cutting body (2) disposed on the top of the support body (1); The cutting body (2) includes a prismatic protrusion (21); The cross-section of the cutting body (2) is circular, and a plurality of the prismatic protrusions (21) are equally spaced around the center of the circle on the side of the cutting body (2) facing away from the support body (1) and converge at the center of the circle to form a cutting tooth center (23).

2. The multi-edge PDC cutting tooth applicable to a hard plastic formation according to claim 1, wherein: An arc chamfer (22) is provided at the protruding portion of the prismatic protrusion (21).

3. The multi-edge PDC cutting tooth applicable to hard plastic formations according to claim 1, wherein: The angle between two of the prismatic protrusions (21) forms a depression on the surface of the cutting body (2).

4. The multi-edge PDC cutting tooth applicable to hard plastic formation according to claim 1, wherein: The number of the prismatic protrusions (21) is six.

5. The multi-edge PDC cutting tooth applicable to hard plastic formation according to claim 1, wherein: The support body (1) is a cylinder.

6. The multi-edge PDC cutting tooth applicable to hard plastic formations according to claim 1, wherein: The distance from the prismatic protrusion (21) to the edge of the cutting body (2) is 1 / 2 of the radius of the circular section of the cutting body (2).

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