A hard metal substrate with a central recessed edge

Abstract

The utility model relates to a hard alloy base body with central concave edge multi-rib, belonging to the technical field of petroleum and geological drilling tools. The upper end face of the base body is provided with a central conical boss, and the arc conical surface on the circumferential outer side is connected and transitioned through an annular convex rib. The arc conical surface is provided with a narrow radial convex rib and a radial wide inclined rib with two wider inclined surfaces and a central arc transition in the radial direction. The two convex ribs are annularly symmetrical, uniformly distributed and arranged at intervals. This structure can limit the load during work to the edge area outside the annular convex rib, the central area is less affected, can effectively block the crack expansion to the center, prevent the whole diamond layer from falling off, and avoid the diameter reduction of the drill bit due to ring abrasion. At the same time, the design of the narrow convex rib and the wide inclined rib improves the stress distribution, improves the bonding strength, and prolongs the service life of the composite sheet. The utility model has flexible and adjustable structure, strong adaptability, can significantly reduce the drill bit failure risk, improve the drilling efficiency, and has significant economic and social benefits.

Description

Technical Field

[0001] This utility model relates to the field of superhard materials technology, specifically a cemented carbide matrix with a concave center and multi-faceted edges. Background Technology

[0002] Diamond composite sheets are ultra-hard composite materials composed of diamond layers and a cemented carbide matrix, widely used in industries such as petroleum, geological drilling, and resource extraction tools. They combine the ultra-high hardness and wear resistance of diamond with the impact resistance and weldability of cemented carbide. With the continuous development of various industries in recent years, higher performance requirements have been placed on composite sheets, including faster drilling speeds, better impact resistance without reducing service life, and greater adaptability to complex geological conditions.

[0003] However, in practical use, when the diamond layer of the composite drill bit is damaged, the common failure mode is the complete detachment of the diamond layer. When the entire diamond layer detaches, the remaining cemented carbide is insufficient to withstand the impact forces during drilling, leading to rapid wear at that location and subsequently causing problems such as circumferential wear and diameter reduction in the drill bit. When the drill bit suffers from severe circumferential wear or diameter reduction, it becomes difficult to repair, resulting in a significant increase in costs.

[0004] During drilling, as the drilling depth increases, the composite diamond layer inevitably wears down and breaks. Once broken, the propagation of cracks gradually penetrates the entire diamond layer, a significant factor leading to its complete detachment. Therefore, to reduce the occurrence of complete detachment when the diamond layer breaks, targeted design of the cemented carbide matrix interface structure is crucial.

[0005] Currently, existing cemented carbide matrix structures can meet the basic requirements of composite drill bits to a certain extent, but they still have some shortcomings when facing complex working conditions and demanding drilling tasks. For example, the stress distribution between the diamond layer and the matrix in traditional matrix structures is not reasonable enough, which makes stress concentration areas prone to crack generation and propagation under impact loads, thus affecting the overall performance and service life of the composite drill bit. In addition, the existing matrix structures have limited ability to prevent crack propagation. Once the edge of the diamond layer is damaged, the crack can easily propagate to the center, eventually causing the entire diamond layer to fall off and the drill bit to fail.

[0006] Therefore, in order to further improve the service life and reliability of diamond composite sheets under complex working conditions and reduce the risk of overall detachment caused by diamond layer damage, it is necessary to improve and optimize the existing cemented carbide matrix structure to meet the ever-increasing industry demands. Utility Model Content

[0007] The purpose of this invention is to provide a cemented carbide substrate with a concave center and multi-faceted edges to solve the problem of insufficient service life and reliability of diamond composite sheets under complex working conditions mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a cemented carbide substrate with a centrally recessed and multi-faceted edge, comprising: a central truncated cone protrusion disposed on the upper end face of the substrate; an annular convex ridge surrounding the central truncated cone protrusion; an arc-shaped conical surface disposed on the outer side of the annular convex ridge; and radially narrow convex ridges and radially wide oblique ridges distributed on the arc-shaped conical surface; wherein the radially narrow convex ridges and radially wide oblique ridges are alternately distributed along an annular interval, and both are annularly symmetrical and uniformly distributed structures; the annular convex ridges connect the central truncated cone protrusion and the arc-shaped conical surface, and divide the end face of the substrate into a central region and an edge region.

[0009] Furthermore, the height of the central truncated cone is lower than the height of the annular ridge.

[0010] Furthermore, the distance between the annular convex ridge and the center of the substrate is 1 / 6 to 5 / 6 of the substrate radius.

[0011] Furthermore, the arc-shaped conical surface is tangentially connected to the annular convex ridge.

[0012] Furthermore, the width of the radially narrow convex ridge is 0.4mm to 3mm, and the thickness increases radially from the center to the edge; its top surface is either flat or curved.

[0013] Furthermore, the bottom of the radial narrow convex ridge transitions to the arc-shaped conical surface through an arc with a radius of 0.1mm to 0.8mm, and the rounded radius of the top corner is 0.1mm to 0.8mm.

[0014] Furthermore, the width of the radial wide bevel is 1.5mm~12mm, and the height is 0.5mm~4.5mm; the included angle of its two bevels is 60°~160°, and the radius of the rounded corner of the top edge is 0.5mm~6mm.

[0015] Furthermore, the top rounding of the radially wide bevel edge is either a constant radius rounding or a variable radius rounding that varies radially.

[0016] Furthermore, the number of annular array units with radially narrow convex ridges is 1 to 10, and each unit contains at least one narrow convex ridge; the number of annular array units with radially wide oblique ridges is 1 to 10, and each unit contains only one wide oblique ridge.

[0017] Furthermore, there are 3 or 4 radial narrow convex ridges and radial wide oblique ridges, which are evenly distributed in a ring at 120° or 90° respectively.

[0018] Compared with the prior art, the beneficial effects of this utility model are:

[0019] 1. Improved impact resistance. By setting a central truncated cone protrusion and annular ridges on the upper end face of the cemented carbide substrate, and distributing two types of ridges on the arc-shaped conical surface, the load on the circumference of the composite sheet is mainly concentrated in the edge area outside the annular ridges during operation, while the central area inside the annular ridges is less affected. This structural design can effectively prevent the circumferential impact stress from being transmitted to the central area, thereby improving the impact resistance of the composite sheet during drill bit use and reducing the overall damage to the diamond layer caused by impact forces.

[0020] 2. Preventing crack propagation. When the diamond layer of the composite sheet is damaged, the annular ridges can prevent the crack from propagating towards the center, controlling the damage within a limited circumference. In addition, the alternating distribution of radially narrow ridges and radially wide oblique ridges can also hinder the crack propagation path to a certain extent, preventing the crack from propagating along the entire diamond layer, thereby effectively preventing the overall collapse and detachment of the diamond layer and reducing the risk of drill bit failure;

[0021] 3. Enhanced Bond Strength. The design of narrow radial ridges and wide radial bevels improves the stress distribution between the diamond layer and the cemented carbide matrix. The narrower radial ridges provide circumferential support to the diamond layer, resisting tangential impact forces along the circumference during drill bit operation; while the wider radial bevels disperse the stress between the matrix and the diamond layer through their curved surfaces and increase the contact area between them, thereby improving the bonding strength of the interface and further extending the service life of the composite sheet during drill bit use.

[0022] 4. Improved service life. This solution, through its rational structural design, effectively solves the problems existing in the composite sheet technology during use, such as the overall detachment of the diamond layer and the reduction in drill bit diameter due to annular wear. This significantly improves the service life of the composite sheet, reduces the frequency of drill bit replacement and maintenance costs, and improves drilling efficiency, bringing significant economic benefits to the petroleum, geological drilling and other industries.

[0023] 5. Flexible and adjustable structure. The position of the annular convex ridge can be adjusted within a certain range, and the number, size, and distribution of the radial narrow convex ridge and the radial wide oblique ridge can also be designed according to actual needs. This makes the cemented carbide matrix of this solution highly flexible and adaptable, and can meet the design requirements of composite plates for different drilling conditions and performance requirements. Attached Figure Description

[0024] Figure 1 This is a perspective view of the cemented carbide substrate according to Embodiment 1 of this utility model.

[0025] Figure 2 This is a top view of the cemented carbide substrate according to Embodiment 1 of this utility model.

[0026] Figure 3 This is a schematic diagram of the cross-sectional position 1 of the cemented carbide substrate in Embodiment 1 of this utility model.

[0027] Figure 4 This is a profile view of the cross-sectional position 1 of the cemented carbide substrate in Embodiment 1 of this utility model.

[0028] Figure 5 This is a schematic diagram of the cross-sectional position 2 of the cemented carbide substrate in Embodiment 1 of this utility model.

[0029] Figure 6 This is a profile view of the cross-sectional position 2 of the cemented carbide substrate in Embodiment 1 of this utility model.

[0030] Figure 7 This is a three-dimensional view of the cemented carbide substrate in Embodiment 2 of this utility model.

[0031] In the diagram: 1. Central truncated cone protrusion; 2. Arc-shaped central depression; 3. Annular convex ridge; 4. Arc-shaped conical surface; 5. Radial narrow convex ridge; 6. Radial wide oblique ridge; 7. Conical surface. Detailed Implementation

[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0033] Example 1.

[0034] Please see Figure 1-6 This utility model provides a technical solution: such as Figure 1As shown, this utility model provides a cemented carbide substrate with a central concave and multi-faceted edge structure. The upper surface of the cylindrical substrate has a central truncated cone protrusion 1, which is connected and transitioned to the outer arc-shaped conical surface 4 via an annular protrusion 3. Both the arc-shaped central concave and the annular protrusion 3 have conical surfaces 7. The base radius of the central truncated cone protrusion 1 is 2 mm, and its height relative to the diamond layer interface is 1.3 mm. The radius of the annular protrusion 3 is 4.4 mm, its distance from the center of the composite sheet is approximately 50.5% of its radius, its height relative to the diamond layer interface is 2 mm, and the top width of the protrusion 3 is 0.5 mm. The radius of the arc of the outer arc-shaped conical surface 4 is 6.9 mm, and the edge of the arc-shaped conical surface 4 is 0.5 mm above the diamond layer interface. There are three radially narrow convex ridges 5, evenly distributed at 120° intervals in a ring. There are also three radially wide oblique ridges 6 (the number of radially narrow and wide oblique ridges can be any reasonable number, determined according to actual needs), evenly distributed at 120° intervals in a ring. The radially narrow convex ridge 5 has a height of approximately 0.2mm, a width of 0.7mm, and a corner rounding radius of 0.15mm. The radially wide oblique ridge 6 has a height of 1.1mm, an included angle of 150° between the two oblique surfaces, and a maximum width of 8.1mm at the circumference. The top of the oblique ridge has a variable radius rounding, with rounding radii of 2.4mm, 3.2mm, and 1mm respectively from the edge to the center.

[0035] Example 2.

[0036] In this embodiment, the upper end face of the cylindrical base is provided with a central truncated cone protrusion 1. The central truncated cone protrusion (1) and the outer arc-shaped cone surface (4) are connected and transitioned by an annular ridge (3). The bottom radius of the central truncated cone protrusion (1) is 2 mm, and its height relative to the diamond layer bonding interface is 1.3 mm. The radius of the annular ridge (3) is 4.4 mm, the distance from the center of the composite sheet is about 50.5% of the radius, the height relative to the diamond layer bonding interface is 2 mm, and the top width of the ridge is 0.5 mm. The radius of the arc of the outer arc-shaped cone surface (4) is 6.9 mm, and the height of the edge of the arc-shaped cone surface (4) relative to the diamond layer bonding interface is 0.5 mm. There are 4 radial narrow ridges (5) evenly distributed at 90° intervals in the ring, and 4 radial wide oblique ridges (6) evenly distributed at 90° intervals in the ring (the number of radial narrow ridges and radial wide oblique ridges can be any reasonable number, determined according to actual needs). The radial narrow convex ridge (5) has a height of approximately 0.2 mm, a width of 0.7 mm, and a corner rounding radius of 0.15 mm. The radial wide oblique ridge (6) has a height of 1.1 mm, an angle of 150° between the two oblique surfaces, a maximum width of 8.1 mm at the circumference, and a variable radius rounding at the top of the oblique ridge, with rounding radii of 2.4 mm, 3.2 mm, and 1 mm from the edge to the center.

[0037] In the above embodiments, the dimensions and relative distances of the cylindrical substrate 1 and the various structures located on its upper surface can be designed according to the actual performance requirements of the cemented carbide substrate. Adjustments to the dimensions or specific limitations are all within the scope of protection of this utility model.

[0038] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A cemented carbide substrate with a centrally recessed center and multi-faceted edges, characterized in that, include: (1) is a central frustum protrusion on the upper end face of the substrate. The annular ridge (3) surrounds the central truncated cone protrusion (1); An arc-shaped conical surface (4) is set on the outside of the annular protrusion (3); Radial narrow convex ridges (5) and radial wide oblique ridges (6) are distributed on the arc-shaped conical surface (4). Among them, the radial narrow convex ridge (5) and the radial wide oblique ridge (6) are alternately distributed along the annular interval, and both are annular symmetrical and uniformly distributed structures; The annular convex ridge (3) connects the central truncated cone protrusion (1) and the arc-shaped cone surface (4), and divides the end face of the base into a central region and an edge region.

2. The cemented carbide matrix according to claim 1, characterized in that: The height of the central conical protrusion (1) is lower than the height of the annular protrusion (3).

3. The cemented carbide matrix according to claim 1, characterized in that: The distance between the annular protrusion (3) and the center of the substrate is 1 / 6 to 5 / 6 of the radius of the substrate.

4. The cemented carbide matrix according to claim 1, characterized in that: The arc-shaped conical surface (4) is tangentially connected to the annular convex edge (3).

5. The cemented carbide matrix according to claim 1, characterized in that: The width of the radial narrow ridge (5) is 0.4mm~3mm, and the thickness increases radially from the center to the edge; Its top surface can be either flat or curved.

6. The cemented carbide matrix according to claim 5, characterized in that: The bottom of the radial narrow convex ridge (5) and the arc-shaped conical surface (4) are transitioned by an arc with a radius of 0.1mm to 0.8mm, and the rounded radius of the top corner is 0.1mm to 0.8mm.

7. The cemented carbide matrix according to claim 1, characterized in that: The width of the radial wide bevel (6) is 1.5mm~12mm, and the height is 0.5mm~4.5mm; the included angle of its two bevels is 60°~160°, and the radius of the rounded corner of the top edge is 0.5mm~6mm.

8. The cemented carbide matrix according to claim 7, characterized in that: The top rounding of the radial wide oblique edge (6) is either a constant radius rounding or a variable radius rounding that varies radially.

9. The cemented carbide matrix according to claim 1, characterized in that: The number of annular array units of the radial narrow convex ridge (5) is 1 to 10, and each unit contains at least one narrow convex ridge; the number of annular array units of the radial wide oblique ridge (6) is 1 to 10, and each unit contains only one wide oblique ridge.

10. The cemented carbide matrix according to claim 9, characterized in that: The number of radial narrow convex ridges (5) and radial wide oblique ridges (6) are 3 or 4, and they are evenly distributed in a ring at 120° or 90° respectively.

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