Diamond impregnated tooth and preparation method thereof

Abstract

The invention discloses a diamond impregnated tooth. The diamond impregnated tooth comprises the following components: a matrix component, a bonding component and diamond particles, wherein the matrix comprises the following components: tungsten carbide powder, iron-copper-cobalt pre-alloyed powder and copper-tin pre-alloyed powder; the bonding component comprises epoxy resin; the diamond particles comprise natural diamond particles or artificial diamond particles. According to the high-wear-resistance composite drill bit formed by matching the diamond impregnated teeth with the PDC compacts, the rock breaking efficiency and the drilling rate of the composite drill bit can be effectively improved, the tripping times of a deep complex stratum are reduced, and the well drilling period and cost are reduced.

Description

Technical Field

[0001] The invention relates to the technical field of diamond impregnated teeth, and in particular to a diamond impregnated tooth and a preparation method thereof. Background Art

[0002] With the continuous improvement of the exploration level, the shallow and easy-to-develop oil and gas resources have gradually decreased, and the development of deep formation oil and gas resources is imperative. The drilling of deep and ultra-deep wells often encounters highly abrasive hard formations such as sandstone and granite. In the past, roller bits, PDC bits and diamond bits were mostly used for drilling in such formations. However, roller bits have low rock breaking efficiency, a single drill bit has a small footage, and are prone to downhole accidents such as roller loss; PDC bits wear quickly and are difficult to drill; diamond bits also have the problems of slow drilling speed and short life, which seriously restricts the speed of oil and gas exploration and development.

[0003] In response to the above problems, a high wear-resistant composite drill bit combining PDC composite pieces and diamond impregnated teeth has been developed. Diamond impregnated teeth are one of the key rock breaking components, and their performance directly affects the use effect of the drill bit. An important way to improve the performance of such drill bits is to improve the performance of the matrix. The matrix formula used should have good physical and mechanical properties, match the parameters of the diamond used, and have appropriate advanced wear.

[0004] For highly abrasive and hard formations, the matrix formula can be adjusted in two ways. First, on the basis of the traditional tungsten carbide-based matrix, the specific gravity of tungsten carbide can be increased to improve the matrix's diamond encapsulation and wear resistance; second, the matrix composition can be adjusted to replace part of the tungsten carbide with ferrophosphorus to broaden the drill bit's adaptability to different rock formations and reduce production costs. However, the above method has the following problems: ① As the specific gravity of tungsten carbide increases, the drill bit sintering temperature also increases, resulting in a decrease in the quality of diamonds; ② The overall performance of hot-pressed high-ferrophosphorus-based diamond drill bits is still low. Although it can effectively target hard and weakly abrasive formations, it has no obvious effect on highly abrasive formations.

[0005] Therefore, how to provide a kind of impregnated insert suitable for hard formations with strong abrasiveness and form a highly wear-resistant composite drill bit by combining with PDC composite sheets has become a technical problem that urgently needs to be solved. Summary of the invention

[0006] The present invention aims to provide a high wear-resistant composite drill bit formed by diamond impregnated teeth and PDC composite sheets, which can effectively improve the rock breaking efficiency and drilling footage of the composite drill bit, reduce the number of trips in deep and complex formations, and reduce the drilling cycle and cost.

[0007] To achieve the above object, the present invention provides a diamond impregnated insert, the components of which include: a matrix component, a bonding component and diamond particles;

[0008] The matrix components include: tungsten carbide powder, iron-copper-cobalt pre-alloy powder, copper-tin pre-alloy powder; the bonding components include: epoxy resin; the diamond particles include: natural diamond particles or artificial diamond particles.

[0009] The present invention also provides a method for preparing a diamond impregnated tooth, the method comprising:

[0010] The tungsten carbide powder, the iron-copper-cobalt pre-alloy powder, and the copper-tin pre-alloy powder are first mixed to obtain a matrix component;

[0011] The carcass component and the bonding component are mixed for a second time to obtain a carcass mixture;

[0012] The matrix mixture is placed layer by layer into a graphite mold, and diamond particles are mixed with the matrix mixture in a layered and orderly arranged manner to obtain a diamond impregnated tooth mixture;

[0013] The diamond impregnated tooth mixture is subjected to hot pressing and sintering treatment to obtain a diamond impregnated tooth.

[0014] The present invention also provides an application of a diamond impregnated tooth, and the diamond impregnated tooth is applied to a high wear-resistant composite drill bit.

[0015] Technical effects and advantages of the present invention:

[0016] The present invention provides a diamond impregnated insert, the components of which include: a matrix component, a bonding component and diamond particles; wherein the matrix component includes: tungsten carbide powder, iron-copper-cobalt pre-alloy powder, copper-tin pre-alloy powder; the bonding component includes: epoxy resin; the diamond particles include: natural diamond particles or artificial diamond particles. The diamond impregnated insert in the present invention is combined with a PDC composite sheet to form a high-wear-resistant composite drill bit, which can effectively improve the rock breaking efficiency and drilling footage of the composite drill bit, reduce the number of trips in deep and complex formations, and reduce the drilling cycle and cost.

[0017] Other features and advantages of the present invention will be described in the following description, and partly become obvious from the description, or be understood by implementing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures pointed out in the description and the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a structural diagram of diamond impregnated teeth. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0021] The invention discloses a diamond impregnated insert. The components of the diamond impregnated insert include: a matrix component, a bonding component and diamond particles.

[0022] The matrix components include: tungsten carbide powder, iron-copper-cobalt pre-alloy powder, copper-tin pre-alloy powder; the bonding components include: epoxy resin; the diamond particles can be: natural diamond particles or artificial diamond particles.

[0023] The total mass of the matrix components is 100%, and the mass ratios of the components are: 59% to 64% of tungsten carbide powder, 14% to 16% of iron-copper-cobalt pre-alloy powder, and 24% to 26% of copper-tin pre-alloy powder.

[0024] Among them, the total mass of iron-copper-cobalt pre-alloyed powder is recorded as 100%, and the mass ratios of each component are: iron 61% to 63%, copper 10% to 12%, cobalt 16% to 18%, tin 4% to 6%, phosphorus 4% to 6%, and it is produced by atomization method.

[0025] The total mass of the copper-tin pre-alloyed powder is recorded as 100%, and the mass ratios of the components are respectively: 80% copper and 20% tin, and the powder is prepared by an atomization method.

[0026] The mass / volume ratio of the carcass component to the bonding component is 25g:1ml to 25g:3ml.

[0027] The standard concentration of the diamond particles (ie, the diamond concentration) is 95% to 100%. The particle size of the diamond particles is 20 to 45 meshes.

[0028] It should also be noted that the diamond impregnated insert provided by the present invention has been improved not only in terms of material, but also in terms of structure, as follows:

[0029] The structure of the diamond impregnated tooth is cylindrical. The structure of the impregnated tooth abandons the traditional full impregnated structure design idea and adopts a semi-impregnated structure design. Among them, the diamond particles in the impregnated layer are arranged in layers regularly; while the non-impregnated layer is the part where the impregnated tooth is welded to the drill body, and does not contain diamond particles inside. Figure 1 shown.

[0030] The structural characteristics of the new impregnated tooth bring about the following beneficial effects: ① The semi-impregnated structural design reduces the amount of diamond used and reduces the manufacturing cost of the impregnated tooth; ② Since the welding part between the impregnated tooth and the drill bit does not contain diamond particles, the welding strength between the impregnated tooth and the drill bit body is improved, avoiding the impregnated tooth falling off under the impact of the hybrid drill bit.

[0031] The hardness of the diamond impregnated teeth is HRC45-48, and the bending strength is 630MPa.

[0032] The present invention also provides an application of a diamond impregnated tooth, characterized in that the diamond impregnated tooth is applied to a high wear-resistant composite drill bit.

[0033] Specifically, the high wear-resistant composite drill bit constructed by the present invention has been applied in Songliao igneous rock formations. Compared with PDC drill bits, the mechanical drilling speed of the composite drill bit is increased by 127%, and the footage of a single drill bit is increased by 314.70%. Compared with roller drill bits, the mechanical drilling speed of the composite drill bit is increased by 184.1%, and the footage of a single drill bit is increased by 236.79%.

[0034] The present invention also provides a method for preparing a diamond impregnated tooth, the method comprising:

[0035] 1. Firstly mix tungsten carbide powder, iron-copper-cobalt pre-alloy powder and copper-tin pre-alloy powder to obtain a matrix component;

[0036] 2. performing a second mixing of the carcass component and the bonding component to obtain a carcass mixture;

[0037] 3. Putting the matrix mixture layer by layer into a graphite mold, and mixing the diamond particles with the matrix mixture in a layered and orderly arranged manner to obtain a diamond impregnated tooth mixture;

[0038] 4. Perform hot pressing and sintering treatment on the diamond impregnated tooth mixture to obtain a diamond impregnated tooth.

[0039] Wherein, the first mixing is carried out by mixing in a mixer, and the mixing time is 1 hour.

[0040] Before placing the matrix mixture layer by layer into the graphite mold, the method further includes: drying the matrix mixture in a drying box;

[0041] Among them, the drying temperature is 70-80°C and the drying time is 1 hour.

[0042] The conditions for the hot pressing sintering treatment include: heating to 500°C and maintaining the temperature for 1 hour, pressurizing to 30MPa at 500°C, and further heating to 900°C at 30MPa, and maintaining the temperature for 2 hours.

[0043] In order to better explain the present invention, examples are also provided below.

[0044] A method for preparing a diamond impregnated tooth, the specific steps are as follows:

[0045] 1. According to the mass percentage, 60% of tungsten carbide powder, 15% of iron-copper-cobalt pre-alloy powder, and 25% of copper-tin pre-alloy powder are charged into a mixer and mixed thoroughly for 1 hour to obtain a matrix component.

[0046] 2. Take out the carcass component from the mixer and put it into a glass dish, mix the carcass component and the bonding component in a mass / volume ratio of 25g:2ml, and mix them evenly to obtain a carcass mixture.

[0047] 3. Dry the tire mixture in a drying oven at 70°C for 1 hour.

[0048] 4. Place 40 / 45 mesh natural diamond particles in a layered and orderly arranged manner with the dried matrix mixture into a graphite mold to obtain a diamond impregnated tooth mixture; wherein the standard concentration of the diamond particles is 100%.

[0049] 5. Put the graphite mold into the hot pressing sintering device and start hot pressing sintering. In the first stage, the temperature is raised to 500℃ and kept constant for 1 hour, and the pressure is increased to 30MPa. In the second stage, the pressure is kept constant, the temperature is raised to 900℃ and kept constant for 2 hours. In the third stage, the heating is stopped, and the mold is demoulded after natural cooling. The demoulding operation is smooth, and the obtained diamond impregnated tooth has a regular shape, which is a standard cylinder.

[0050] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A diamond impregnated tooth, characterized in that: The components of the diamond impregnated insert include: a matrix component, a bonding component and diamond particles; The matrix components include: tungsten carbide powder, iron-copper-cobalt pre-alloy powder, copper-tin pre-alloy powder; the bonding components include: epoxy resin; the diamond particles include: natural diamond particles or artificial diamond particles.

2. The diamond impregnated tooth according to claim 1, characterized in that: The mass fractions of the tungsten carbide powder, the iron-copper-cobalt pre-alloy powder and the copper-tin pre-alloy powder in the matrix component are 59%-64%, 14%-16% and 24%-26% respectively.

3. The diamond impregnated tooth according to claim 1, characterized in that: The mass fractions of the elements in the iron-copper-cobalt pre-alloyed powder are: 61%-63% of iron, 10%-12% of copper, 16%-18% of cobalt, 4%-6% of tin, and 4%-6% of phosphorus.

4. The diamond impregnated tooth according to claim 1, characterized in that: The mass fractions of the elements in the copper-tin pre-alloyed powder are: 80% copper and 20% tin.

5. The diamond impregnated tooth according to claim 1, characterized in that: The ratio of the mass of the carcass component to the volume of the bonding component is in the range of 25g:1ml to 25g:3ml.

6. The diamond impregnated tooth according to claim 1, characterized in that: The concentration of the diamond particles is 95%-100%, and the particle size of the diamond particles is 20-45 meshes.

7. The diamond impregnated tooth according to claim 1, characterized in that: The structure of the diamond impregnated tooth is cylindrical, and half of the cylindrical shape is an impregnated layer, and the other half is a non-impregnated layer; Wherein, diamond particles are regularly arranged in layers and arranged in the impregnated layer.

8. The diamond impregnated tooth according to claim 1, characterized in that: The hardness of the diamond impregnated tooth is HRC45-48, and the bending strength is 630MPa.

9. A method for preparing a diamond impregnated insert according to any one of claims 1 to 8, characterized in that: The method comprises: The tungsten carbide powder, the iron-copper-cobalt pre-alloy powder, and the copper-tin pre-alloy powder are first mixed to obtain a matrix component; The carcass component and the bonding component are mixed for a second time to obtain a carcass mixture; The matrix mixture is placed layer by layer into a graphite mold, and diamond particles are mixed with the matrix mixture in a layered and orderly arranged manner to obtain a diamond impregnated tooth mixture; The diamond impregnated tooth mixture is subjected to hot pressing and sintering treatment to obtain a diamond impregnated tooth.

10. The method according to claim 9, characterized in that The first mixing is carried out by using a mixer, and the mixing time is 1 hour.

11. The method according to claim 9, characterized in that Before placing the matrix mixture layer by layer into the graphite mold, the method further includes: drying the matrix mixture in a drying box; Among them, the drying temperature is 70-80°C and the drying time is 1 hour.

12. The method according to claim 9, characterized in that The conditions of the hot pressing sintering treatment include: heating to 500° C. and maintaining the temperature for 1 hour, pressurizing to 30 MPa at 500° C., and further heating to 900° C. at 30 MPa, and maintaining the temperature for 2 hours.

13. The use of a diamond impregnated insert according to any one of claims 1 to 8, characterized in that: The diamond impregnated teeth are used in highly wear-resistant composite drill bits.

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