A ridge type diamond compact

Abstract

The invention relates to a ridge type diamond compact, comprising a cylindrical cemented carbide base and a diamond composite layer, the diamond composite layer is arranged at one end of the cemented carbide base, and the two are integrated, the end surface of the diamond composite layer is provided with a plurality of ridges, each ridge is connected through a slope and a transition curved surface, characterized in that the ridges extend from the edge of the end surface to the center of the end surface, and the ridges comprise positive ridges extending upward and negative ridges extending downward. The invention not only has strong ability to eat into the stratum and realizes different attack abilities, but also has strong impact resistance; the positive and negative ridges and the slope constitute a smooth concave-convex fluctuation diamond composite layer end surface, combined with the combination of the up-and-down fluctuation edge cutting edges and the ridges, a plurality of different performance cutting edges of the compact are formed, so that the same diamond compact can meet the drilling requirements of different strata and realize the integration of different attack abilities.

Description

Technical Field

[0001] This invention relates to a ridged diamond composite sheet, belonging to the field of petroleum drilling technology. Background Technology

[0002] Since the 1980s, diamond drill bits have been increasingly used in oil and gas drilling projects. Diamond drill bits mainly consist of a drill body and cutting elements. Based on their cutting elements, diamond drill bits are divided into three categories: PDC (polycrystalline diamond) drill bits, TSP (thermally stabilized polycrystalline diamond) drill bits, and natural diamond drill bits. PDC drill bits are mainly used for drilling in soft to medium-hard formations. With continuous technological advancements, the application range of PDC drill bits has become increasingly wider, offering good economic value. TSP drill bits are mainly used for drilling in medium-hard to extremely hard formations. Currently, deep well operations are gradually increasing in oil and gas drilling projects, and the formations encountered are becoming increasingly complex.

[0003] Existing diamond composite cutting tools mostly have planar cutting ends, making it difficult for them to penetrate the formation and achieve effective cutting when encountering dense mudstone. Furthermore, after passing through this dense layer, the formation becomes increasingly variable in hardness, subjecting the composite tool to significant impact loads. This can lead to tooth breakage and ultimately, drill bit failure. Therefore, there is an urgent need for a diamond composite cutting tool with strong impact resistance and formation penetration capabilities. Current methods primarily improve the impact resistance of diamond composite cutting tools by altering the interface structure between the diamond layer and the cemented carbide base to reduce residual stress, or by changing the material formulation and processing technology. Some tools employ irregularly shaped PDC (diamond-carbide composite) layers, such as spherical or conical teeth. While these irregular PDC structures improve impact resistance, they also result in high drilling cutting resistance, high drill bit torque, and low drilling efficiency. To address this issue, Chinese Patent 201520471001.4 discloses a low-cutting-resistance curved surface polycrystalline diamond composite sheet, which improves drilling efficiency in complex formations, but its utilization rate and chip removal effect are not ideal. Chinese Patent 201521102644.8 discloses a multi-bladed irregularly shaped polycrystalline diamond composite sheet, which improves drilling efficiency and utilization in complex formations, but suffers from problems such as obstructed chip removal channels. Chinese Patent 201721327355.7 discloses a convex ridge tooth with different cutting widths, enabling application in multiple formations with a single tooth, but suffers from the problem of a narrow application range for wide-bladed convex ridge teeth. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a ridged diamond composite sheet that not only has strong impact resistance but also has multiple attack capabilities and can effectively adapt to various geological formations.

[0005] The technical solution adopted by the present invention to solve the above-mentioned problems is as follows: it includes a columnar cemented carbide substrate and a diamond composite layer, wherein the diamond composite layer is disposed at one end of the cemented carbide substrate and the two are connected as one unit, and the end face of the diamond composite layer is provided with multiple ridges, and the ridges are connected to each other by inclined surfaces and transition surfaces. The ridges are characterized in that they extend from the edge of the end face to the center of the end face, and the ridges include positive ridges extending upward and negative ridges extending downward.

[0006] According to the above scheme, the angle between the line connecting the two ends of the upwardly extending positive convex ridge and the bottom plane of the diamond composite layer is 0 to 20°. Further, the angle of the positive convex ridge is 3 to 10°, and the bottom plane of the diamond composite layer is perpendicular to the axis of the cylindrical cemented carbide substrate.

[0007] According to the above scheme, the angle between the line connecting the two ends of the downwardly extending negative ridge and the bottom plane of the diamond composite layer is less than 0° to -20°. Further, the angle of the negative ridge is -3 to -10°, and the bottom plane of the diamond composite layer is perpendicular to the axis of the cylindrical cemented carbide substrate.

[0008] According to the above scheme, there are 3 to 6 ridges, which are distributed at intervals along the circumference.

[0009] According to the above scheme, the end face edge is provided with two or more different chamfers to form different undulating edge cutting edges. The chamfer slope is one or more of the following: inclined surface chamfer, bent surface chamfer, and curved surface chamfer.

[0010] According to the above scheme, the ridge extends straight from the edge of the end face to the center of the end face, or is an arched arc or a concave arc, that is, the lateral profile of the ridge top is a straight line, an upward convex arc, or a downward concave arc.

[0011] According to the above scheme, the shape of the convex ridge is an arc surface, a curved surface, a plane, or an edge, that is, the positive profile of the convex ridge is an arc, a curve, a straight line, or a broken line.

[0012] According to the above scheme, the positive and negative convex ridges are arranged alternately along the circumference.

[0013] According to the above scheme, the two sides of the convex ridge are connected to downward inclined surfaces, which are either planes or curved surfaces. The inclined surfaces are connected by transition curved surfaces, thereby forming an uneven diamond composite layer end face.

[0014] According to the above scheme, the radial cross section of the diamond composite layer is the same as the radial cross section of the cemented carbide matrix, which is circular, elliptical, or regular polygonal.

[0015] The beneficial effects of this invention are as follows: 1. By setting positive and negative ridges on the end face of the diamond composite layer, the diamond composite sheet not only has a strong ability to penetrate the formation and achieve different attack capabilities, but also has strong impact resistance; 2. The positive and negative ridges and the inclined surface form a smooth, undulating diamond composite layer end face. Combined with the undulating edge cutting edge and the ridge, a variety of cutting edges with different properties are formed in the composite sheet. This allows the same diamond composite sheet to meet the drilling needs of different formations and achieve the integration of different attack capabilities, further enhancing the attack capability and impact resistance of the diamond composite sheet. When rationally arranged on the diamond drill bit, the diamond drill bit can adapt to the drilling needs of various complex formations. Attached Figure Description

[0016] Figures 1 to 4 These are, respectively, a perspective view, a top view, a front view, and a side view of an embodiment of the present invention.

[0017] Figures 5 to 8 These are, respectively, a perspective view, a top view, a front view, and a side view of the second embodiment of the present invention. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0019] The first implementation example Figures 1 to 4As shown, it includes a cylindrical cemented carbide substrate 102 and a diamond composite layer 101. The diamond composite layer is disposed at one end of the cemented carbide substrate. The diamond composite layer is a polycrystalline diamond composite layer. The diamond composite layer and the cemented carbide substrate are bonded together by ultra-high temperature and high pressure sintering. The bonding surface between the cemented carbide substrate and the diamond composite layer is a plane, a bump surface, or a groove surface. The diamond composite layer has four ridges on its end face, including two upward-extending positive ridges 103 and 105 and two downward-extending negative ridges 104 and 106. The positive and negative ridges are evenly distributed and staggered along the circumference. Each ridge extends from the edge of the end face to the center of the end face. The two positive ridges gradually increase in height from the edge to the center and extend to the center of the end face, while the two negative ridges gradually decrease in height from the edge to the front end and extend to about half the distance from the center of the end face. Each ridge is arc-shaped, that is, the positive profile of the ridge is a circular arc with the same radius of curvature R1, R2, R3, and R4, which can also be different. The ridges extend straight from the edge of the end face to the center of the end face. The two upward-extending positive convex ridges form angles β and α of 5° with the line connecting their top ends to the bottom plane of the diamond composite layer. The two downward-extending negative convex ridges form angles θ and γ of -5° with the line connecting their top ends to the bottom plane of the diamond composite layer. The bottom plane of the diamond composite layer is perpendicular to the axis of the cylindrical cemented carbide substrate. The convex ridges are smoothly connected to downward-sloping planar surfaces on both sides. These planar surfaces are planes, including planar surfaces 107 and 108 on both sides of positive convex ridge 103, planar surfaces 109 and 110 on both sides of negative convex ridge 104, planar surfaces 111 and 112 on both sides of positive convex ridge 105, and planar surfaces 113 and 114 on both sides of negative convex ridge 106. These planar surfaces are smoothly connected by transition surfaces, thus forming the undulating end face of the diamond composite layer. The end face edge is provided with two different chamfers: a bevel chamfer and a rounded chamfer. Specifically, the chamfer is a rounded chamfer within a 90° range around the positive ridge, and a bevel chamfer within a 90° range around the negative ridge. This creates different undulating cutting edges along the entire outer periphery of the end face, which, combined with the various ridges, form multiple cutting edges with different properties in the composite sheet. In this embodiment, the diamond composite sheet has a circular radial cross-section with a diameter of 15.8 mm.

[0020] The second implementation example Figures 5 to 8As shown, its difference from the previous embodiment is that the two positive convex ridges 203 and 205 are raised arc lines, forming an arched shape from the edge of the end face to the center of the end face. The lateral profile of the ridge top is an upward convex arc line. The angle δ between the line connecting the two ends of the ridge top of the two upwardly extending positive convex ridges and the bottom plane of the diamond composite layer is 5°. The two positive convex ridges have the same structure, gradually increasing in height from the edge to the center, extending to the center of the end face. The two negative convex ridges 204 and 206 are concave arc lines, forming a concave arc shape from the edge of the end face to the center of the end face. The lateral profile of the ridge top is a concave arc line. The angle ε between the line connecting the two ends of the ridge top of the downwardly extending negative convex ridges and the bottom plane of the diamond composite layer is -5°. The four ridges 203, 204, 205, and 206 on the end face of the diamond composite layer have curved surfaces on both sides. These curved surfaces are smoothly connected by transition surfaces, thus forming an undulating diamond composite layer end face. Other structures are the same as in the previous embodiment.

Claims

1. A ridged diamond composite sheet, comprising a columnar cemented carbide substrate and a diamond composite layer, wherein the diamond composite layer is disposed at one end of the cemented carbide substrate, the two being integrally connected, and the end face of the diamond composite layer is provided with multiple ridges, the ridges being connected by inclined surfaces and transition surfaces, characterized in that... The convex ridges extend from the edge of the end face towards the center of the end face. Each convex ridge includes an upwardly extending positive convex ridge and a downwardly extending negative convex ridge. The angle between the line connecting the two ends of the upwardly extending positive convex ridge and the bottom plane of the diamond composite layer is 3-10°. The angle between the line connecting the two ends of the downwardly extending negative convex ridge and the bottom plane of the diamond composite layer is -3 to -10°. The bottom plane of the diamond composite layer is perpendicular to the axis of the cylindrical cemented carbide substrate. The edge of the end face is provided with two or more different chamfers to form different undulating cutting edges. The chamfer slope is one or more of a bevel chamfer, a bent chamfer, or a curved chamfer. The positive and negative convex ridges are staggered along the circumference. There are 3-6 convex ridges, spaced apart along the circumference.

2. The ridged diamond composite sheet according to claim 1, characterized in that... The ridge extends straight from the edge of the end face to the center of the end face, or is an arched or concave arc, that is, the lateral profile of the ridge top is a straight line, an upward convex arc, or a downward concave arc.

3. The ridged diamond composite sheet according to claim 2, characterized in that... The ridge shape is an arc surface, curved surface, plane or edge, that is, the positive profile of the ridge is an arc, curve, straight line or broken line.

4. The ridged diamond composite sheet according to claim 1 or 2, characterized in that... The ridge is connected to two downward sloping surfaces on both sides. The sloping surfaces are either flat or curved. The sloping surfaces are connected by transitional curved surfaces, thereby forming an uneven diamond composite layer end face.

5. The ridged diamond composite sheet according to claim 1, characterized in that... The diamond composite layer has four ridges on its end face, including two positive ridges extending upwards and two negative ridges extending downwards. The positive and negative ridges are evenly distributed and staggered along the circumference. Each ridge extends from the edge of the end face to the center of the end face. The two positive ridges gradually increase in height from the edge to the center and extend to the center of the end face, while the two negative ridges gradually decrease in height from the edge to the front end and extend to about half the distance from the center of the end face.

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