CN222436301U - Novel easy-to-remove cobalt concave ridge type cutting element - Google Patents

Abstract

The utility model discloses a novel cobalt-free concave ridge type cutting element which comprises a hard alloy substrate and a diamond composite layer, wherein at least 1 ridge extending from a radial edge to the center of a cylinder is arranged on the end surface of the diamond composite layer, a cutting edge is formed at the highest position of the ridge, the thinnest position of the diamond composite layer is a plane, an inclined plane or a curved surface, and the thickness of the thinnest position of the diamond composite layer is larger than or equal to 0.8mm. The utility model has strong aggressiveness and is easier to remove cobalt deeply, the stratum is cut by the concave ridge profile, the cutting surface has stronger plow function, the breaking drilling performance of the composite sheet is improved, the drilling cutting resistance is reduced, and the mechanical drilling speed of the diamond bit is further improved.

Description

Novel easy-to-remove cobalt concave ridge type cutting element

Technical Field

The utility model relates to the field of diamond compacts. More particularly, the present utility model relates to a novel free-cobalt female ridged cutting element.

Background

Beginning in the 80 s of the last century, diamond bits were widely used in oil and gas drilling projects. Diamond bits are mainly composed of a bit body and cutting elements, and are classified into PDC (polycrystalline diamond) bits, TSP (thermally stable polycrystalline diamond) bits, and natural diamond bits according to the cutting elements. The PDC drill bit is mainly used for drilling soft to medium hard stratum, and has wider and wider application range and better economic value through continuous technological progress. TSP bits are mainly used for drilling medium to very hard formations. At present, deep well operation in petroleum and natural gas drilling engineering is gradually increased, and stratum encountered by drilling is also more and more complicated.

When drilling and encountering dense mudstone, the diamond compact is difficult to eat into the stratum to form effective cutting. When the compact layer is penetrated, the stratum is soft and hard staggered, the change is more frequent, the impact load applied to the composite sheet is larger, and the diamond composite sheet is easy to collapse and fail, so that the whole drill bit fails. Thus, a diamond compact with high impact resistance and high stratum penetration is urgently needed in the drilling site. The impact resistance of the existing diamond composite sheet is mainly improved by changing the interface structure of the diamond layer and the hard alloy base in the diamond composite sheet to reduce the residual stress, or changing the material formula and the processing technology. The PCD layer with special-shaped teeth such as a ball head shape and a cone shape is adopted, and the PDC with the special-shaped structure improves the impact resistance, but has the phenomena of large drilling and cutting resistance, large drill torque, low drilling efficiency and the like in the using process. Patent CN109681125A provides a concave ridge tooth diamond compact, which has better capability of pressing into stratum and higher cutting efficiency, but the thickness of diamond layer layers on two sides of ridge is smaller, which is unfavorable for the compact to adopt deep cobalt removal treatment process to improve the wear resistance of the compact.

Disclosure of utility model

The utility model aims to provide a novel cobalt-free concave ridge type cutting element which is strong in aggressiveness and easier to remove cobalt deeply.

The utility model solves the technical problem by adopting the technical proposal that the novel cobalt-free concave ridge type cutting element comprises a hard alloy matrix and a diamond composite layer, wherein the end surface of the diamond composite layer is provided with at least 1 ridge extending from the radial edge to the center of a cylinder, and the highest part of the ridge forms a cutting edge;

The thinnest part of the diamond composite layer is a plane, an inclined plane or a curved surface, and the thickness of the thinnest part of the diamond composite layer is more than or equal to 0.8mm.

Preferably, the end face of the diamond composite layer is provided with at least 1 convex ridge which is concave inwards from the radial edge to the center of the cylinder.

Preferably, the thickness of the thinnest part of the diamond composite layer is 0.8 mm-1.5 mm.

Preferably, the plurality of ridges are arranged at a certain included angle, and the included angle is between 0 and 180 degrees. The angle between the cutting edge formed by the plurality of ridges and the bottom surface of the hard alloy can be the same or different.

Preferably, the number of cutting edges is 1 to 10.

Preferably, the ridge is shaped as a line, a plane, an arc or a gradual curved surface.

Preferably, the ridge and the hard alloy bottom plane form a certain included angle, and the included angle is 1-20 degrees.

Preferably, the width of the ridge is 0-4 mm, excluding 0mm and including 4mm.

Preferably, two sides of the ridge are planes, inclined planes, cambered surfaces or a combination of the planes and the cambered surfaces.

Preferably, the radial cross section of the diamond composite layer is circular or elliptical.

Preferably, the bonding surface between the cemented carbide substrate and the diamond composite layer is planar, concave-convex, or grooved, annular grooved, or the like.

Preferably, the center of the diamond composite layer cylinder can be naturally transited by an inner concave-convex ridge, and can also be connected and transited between a platform and the convex ridge.

The utility model at least comprises the following beneficial effects:

1) The stratum is cut through the concave ridge profile, the cutting surface has a strong plow effect, the breaking drilling performance of the composite sheet is improved, the drilling cutting resistance is reduced, and the mechanical drilling speed of the diamond bit is further improved.

2) A plane, an inclined plane and a curved plane are arranged at two sides of the concave ridge molded surface in the diamond layer, so that the thinnest thickness of the edge is larger than a certain size, and the thinnest thickness of the diamond layer exceeds the safety value of the deep cobalt removal process, so that the diamond layer can be subjected to deep cobalt removal treatment, the corrosion of a hard alloy matrix in the cobalt removal treatment is prevented, and the deep cobalt removal process can be adopted, so that better wear resistance can be obtained.

Additional advantages, objects, and features of the utility model will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the utility model.

Drawings

Fig. 1 is a perspective view of a first embodiment.

Fig. 2 is a top view of the first embodiment.

Fig. 3 is a rear view of the first embodiment.

Fig. 4 is a side view of the first embodiment.

Fig. 5 is a perspective view of the second embodiment.

Fig. 6 is a top view of the second embodiment.

Fig. 7 is a rear view of the second embodiment.

Fig. 8 is a side view of the second embodiment.

Fig. 9 is a perspective view of the third embodiment.

Fig. 10 is a perspective view of the fourth embodiment.

Fig. 11 is a perspective view of the fifth embodiment.

Detailed Description

The present utility model will be described more fully hereinafter with reference to the accompanying examples. Those of ordinary skill in the art will be able to implement the utility model based on these descriptions. Before explaining the present utility model in connection with the embodiments, it should be noted in particular that the technical solutions and technical features provided in the respective sections including the following description of the present utility model may be combined with each other without conflict.

In addition, the embodiments of the present utility model referred to in the following description are typically only some, but not all, embodiments of the present utility model. Therefore, all other embodiments, which can be made by one of ordinary skill in the art without undue burden, are intended to be within the scope of the present utility model, based on the embodiments of the present utility model.

The utility model is further described in detail below with reference to examples and implementations, which are performed as follows:

An embodiment is shown in fig. 1 to 4, and comprises a diamond composite layer 101 and a hard alloy substrate 102, wherein the end surface of the diamond composite layer is provided with 1 ridge 103, and the ridge 103, side inclined surfaces 104 and 105 on two sides of the ridge, two side plane surfaces 108 and 109 and transition surfaces 106 and 107 between the two side inclined surfaces and the two side plane surfaces form the surface of the diamond composite layer. In this embodiment, the ridge is an arc surface, the radius of curvature is 4mm, the cutting edge width L is 2.1mm, and the angle α between the ridge 103 and the bottom plane of 102 is 5 degrees. The included angle between the inclined planes 104, 105 and the bottom plane 102 is 15 degrees. The included angle between the two side planes 108, 109 and the cemented carbide bottom plane is 5 degrees. The radius of the arc of the transition surfaces 106, 107 is 6mm. The radial section of the diamond compact is circular, and the diameter is 15.8mm. The thinnest thickness of the diamond layer relative to the cemented carbide substrate is 1mm. The edge of the diamond composite layer is provided with a chamfer 110, and the chamfer is an oblique chamfer.

The second embodiment is shown in fig. 5 to 8, and includes a diamond composite layer 101 and a cemented carbide substrate 102, where the end surface of the diamond composite layer has 2 ridges 203 and 204, each ridge extends from the edge of the composite layer to the center of the end surface, and the 2 ridges are uniformly distributed along the circumferential direction, that is, the central angle between two adjacent gradually-changed cambered surface ridges is 180 °. One side of the end surface is composed of a cambered surface convex ridge 203, inclined planes 205 and 206 on two sides of the cambered surface convex ridge, two side planes 209 and 213 and transitional curved surfaces 211 and 212, the convex ridge 203 and the inclined planes on two sides of the cambered surface form a cutting edge, and the other side of the end surface is composed of a convex ridge 204, side inclined planes 207 and 208 on two sides of the cambered surface, two side planes 209 and 213 and transitional curved surfaces 214 and 215, and the convex ridge 204 and the inclined planes on two sides of the cambered surface form another cutting edge. In this embodiment, 2 concave cambered ridges are cambered surfaces, the curvature radius is 4mm, the cutting edge width is 2.1mm, the angle α between the bottom planes of the ridges 203 and 202 is 5 degrees, the angle β between the bottom planes of the ridges 204 and 202 is 5 degrees, the included angle between the inclined planes on both sides and the bottom plane 102 is 15 degrees, the plane on both sides and the bottom plane 202 are parallel, and the radius of the transitional arc surface between the inclined planes on both sides and the plane is 6mm. The thinnest wall thickness of the diamond layer is 1mm. The radial section of the diamond compact is circular, and the diameter is 15.8mm. The edge of the diamond composite layer is provided with a chamfer, and the chamfer can be an oblique chamfer.

Embodiment III as shown in FIG. 9, the end surface of the diamond composite layer is provided with 3 concave-convex ridges 303, 304 and 305, each concave-convex ridge extends from the edge of the composite layer and meets the center of the end surface, and the concave-convex ridges are uniformly distributed along the circumferential direction, namely, the central angles between two adjacent ridges are equal, and the central angle is 120 degrees. Other structures are the same as the embodiment.

The fourth embodiment is shown in fig. 10, and is different from the third embodiment in that the concave cambered surface ridges 403, 404, 405 are gradual cambered surfaces, and the cambered surface curvature radius is in linear transition from the radially outermost edge 1mm to the central curvature radius 3 mm. The three ridges and the bottom plane have the same angle of 5 degrees. The inclined planes at two sides of the ridge are in cambered surface transition with the plane, and the curvature radius of the cambered surface is 6mm.

Embodiment five is shown in fig. 11, and is different from embodiment one in that two side planes 508 and 509 of the ridge are parallel to the cemented carbide bottom plane, and the minimum thickness of the diamond composite layer is 1mm.

Although embodiments of the present utility model have been disclosed above, it is not limited to the details and embodiments shown, it is well suited to various fields of use for which the utility model is suited, and further modifications may be readily made by one skilled in the art, and the utility model is therefore not to be limited to the particular details and examples shown and described herein, without departing from the general concepts defined by the claims and the equivalents thereof.

Claims (10)

1. The novel easy-to-remove cobalt concave ridge type cutting element comprises a hard alloy matrix and a diamond composite layer, and is characterized in that at least 1 ridge extending from the radial edge to the center of a cylinder is arranged on the end surface of the diamond composite layer, and a cutting edge is formed at the highest position of the ridge;

The thinnest part of the diamond composite layer is a plane, an inclined plane or a curved surface, and the thickness of the thinnest part of the diamond composite layer is more than or equal to 0.8mm.

2. The novel cobalt-free concave ridge cutting element according to claim 1, wherein the diamond compact has at least 1 ridge recessed from the radial edge toward the center of the cylinder.

3. The novel cobalt-free concave ridge cutting element according to claim 1 or 2, wherein the thickness of the thinnest part of the diamond composite layer is 0.8 mm-1.5 mm.

4. The novel cobalt-free concave ridge cutting element according to claim 2, wherein the plurality of ridges are disposed at an angle of between 0 ° and 180 °.

5. The novel cobalt-free concave ridge cutting element according to claim 2, wherein the number of the cutting edges is 1-10.

6. The novel cobalt-free concave ridge cutting element according to claim 1 or 2, wherein the ridge shape is a line, a plane, an arc or a gradual curve.

7. The novel cobalt-free concave ridge cutting element according to claim 1 or 2, wherein the ridge forms an angle with the cemented carbide bottom plane of between 1 ° and 20 °.

8. The novel cobalt-free concave ridge cutting element according to claim 1 or 2, wherein the ridge width is between 0 and 4 mm.

9. The novel cobalt-free concave ridge cutting element according to claim 1 or 2, wherein the two sides of the ridge are flat surfaces, inclined surfaces, cambered surfaces or a combination of flat surfaces and cambered surfaces.

10. The novel cobalt-free concave ridge cutting element according to claim 1 or 2, wherein the diamond compact has a circular or oval radial cross-section.