A new type of diamond brazed drill bit

Abstract

The utility model relates to a novel diamond brazing drill bit belongs to the drilling equipment technical field for geological exploration, technical scheme is: the end of steel body is equipped with a plurality of even arrangement's diamond cutting tool along the circumferential direction, and the space between two adjacent diamond cutting tools is water gap, and the cutting surface of diamond cutting tool end is arc lip face, the arc lip face is made of brazing binder inlaying diamond, and the diamond is inlaid in the inside and surface of brazing binder, the utility model has the following active effect: the top of diamond cutting tool is arc lip face, can guarantee that the drill bit effectively eats into the stratum and makes rock produce effective crushing, and can guarantee stability. The diamond is inlaid in the inside and surface of brazing binder, can realize the chemical metallurgical combination of diamond, Ni base binder and metal matrix interface, has higher bonding strength, and the diamond is not easy to fall off, can drill in any rock stratum, and overcomes the problem of low drilling efficiency.

Description

Technical Field

[0001] This utility model relates to a novel diamond brazing drill bit, belonging to the technical field of drilling equipment for geological exploration. Background Technology

[0002] Impregnated diamond drill bits are primarily suitable for medium-hard to hard rocks. In complex and varied geological formations, frequent bit changes significantly reduce production efficiency, waste time, and increase drilling costs. Composite drill bits have a limited range of applications, mainly used in mudstone, sandstone, and loosely cemented small-grained conglomerate, gypsum, and limestone formations, lacking broad applicability. Electroplated diamond drill bits do not exhibit a strong chemical-metallurgical bond between the plating metal and the substrate and abrasive surfaces. The abrasive is merely mechanically embedded, resulting in a heavy diamond particle load and a tendency to detach, leading to weak holding power. Furthermore, the electroplating process causes severe water pollution, hindering environmental management. Utility Model Content

[0003] The purpose of this invention is to provide a novel diamond brazed drill bit that can achieve high drilling performance in hard and dense rock formations, effectively achieving the drilling objective. It is applicable to various geological formations and solves the aforementioned problems in the prior art.

[0004] The technical solution of this utility model is:

[0005] A novel diamond brazed drill bit comprises diamond cutting tools, a sprue, and a steel body. The steel body has multiple uniformly arranged diamond cutting tools at its end along the circumferential direction. The space between two adjacent diamond cutting tools is the sprue. The cutting surface of the end of the diamond cutting tool is an arc-shaped lip. The arc-shaped lip is formed by inlaying diamonds with brazing adhesive, which inlays the diamonds inside and on the surface.

[0006] Furthermore, the brazing bond is a Ni-based bond material.

[0007] Furthermore, the diamond is a 40-60 mesh diamond.

[0008] Furthermore, the cross-section of the diamond cutting tool is an isosceles trapezoid, and the arc-shaped lip is a circular arc-shaped lip, with the middle of the circular arc-shaped lip being higher and the inner and outer surfaces being lower.

[0009] Furthermore, the diamond cutting tool consists of two cutting blocks and a fan-shaped base. The two cutting blocks are symmetrically arranged on the fan-shaped base at intervals. The cutting surfaces at the ends of the two cutting blocks are arc-shaped lips, with the middle of the arc-shaped lip being higher and the left and right sides being lower.

[0010] Furthermore, the diamond cutting tool is a stepped structure arranged sequentially from the inside to the outside. The inside of the stepped structure is high and the outside is low. The upper end face of each step is an arc-shaped lip, with the middle of the arc-shaped lip being high and the inner and outer sides being low.

[0011] Furthermore, the steel body is provided with an annular powder discharge groove at the end adjacent to the diamond cutting tool, and the water inlet is connected to the annular powder discharge groove.

[0012] Furthermore, the water inlet is a fan-shaped water inlet. The fan-shaped water inlet design provides a large water passage area for the drill bit, ensuring sufficient flushing fluid flow for better removal of rock powder.

[0013] The positive effects of this invention are as follows: The diamond cutting tool has a rounded lip at the top, which ensures that the drill bit can effectively penetrate the formation and break the rock, while also ensuring stability. The brazed diamond drill bit, manufactured through a high-temperature brazing process, has the brazing agent embedding the diamond inside and on the surface, achieving a chemical metallurgical bond between the diamond, the Ni-based binder, and the metal matrix. This results in high bonding strength, preventing the diamond from easily detaching. While achieving the same functions as electroplated diamond drill bits, it also features high cutting edge extension and high holding force, enabling drilling into any rock formation and overcoming the problem of low drilling efficiency. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present utility model;

[0015] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of this utility model;

[0016] Figure 3 This is a schematic diagram of the structure of Embodiment 3 of this utility model;

[0017] In the diagram: 1. Arc-shaped lip surface; 2. Diamond cutting tool; 21. Cutting block; 22. Fan-shaped base; 3. Sprue; 4. Annular powder discharge groove; 5. Steel body; 6. Side sprue. Detailed Implementation

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

[0019] A novel diamond brazed drill bit includes a diamond cutting tool 2, a sprue 3, and a steel body 5. The steel body 5 has multiple diamond cutting tools 2 evenly arranged along the circumferential direction at its end. The space between two adjacent diamond cutting tools 2 is the sprue 3. The cutting surface at the end of the diamond cutting tool 2 is an arc-shaped lip surface 1. The arc-shaped lip surface 1 is formed by inlaying diamonds with brazing adhesive, and the brazing adhesive inlays the diamonds inside and on its surface.

[0020] The brazing adhesive is a Ni-based adhesive material, and the Ni-based brazing alloy is composed of 70%-75% Ni by mass, 10%-15% Cr by mass, 2%-4% B by mass, and 3%-5% Si by mass.

[0021] The diamond cutting tool 2 has an arc-shaped lip surface 1 at the top, which can create a free surface in the rock layer at the bottom of the well. The horizontal lateral pressure of the rock around the drill bit on the rock layer at the bottom of the well is reduced, and the rock will be fractured by tensile stress. As a result, it can ensure that the drill bit can effectively penetrate the formation and effectively fracture the rock, while also ensuring stability.

[0022] This invention can be applied to various diamond drill bits and is a general-purpose design. The lip surface of the diamond cutting tool can be designed in various forms without being limited by the manufacturing process. The following three embodiments illustrate the structure of the diamond cutting tool:

[0023] Example 1: The number of diamond cutting tools 2 is 8, and the 8 diamond cutting tools 2 are evenly arranged. The cross-section of the diamond cutting tool 2 is an isosceles trapezoid. The arc-shaped lip surface 1 at the end of the diamond cutting tool 2 is a circular arc-shaped lip surface, with the middle of the circular arc-shaped lip surface being higher and the inner and outer surfaces being lower.

[0024] Example 2: The number of diamond cutting tools 2 is 6, and the 6 diamond cutting tools 2 are evenly arranged in an overall shape similar to wheel teeth. Each diamond cutting tool 2 consists of two cutting blocks 21 and a fan-shaped base 22. The two cutting blocks 21 are symmetrically arranged on the fan-shaped base 22 at intervals. The fan-shaped base 22 is connected to the steel body 5. The cross-section of the fan-shaped base 22 is an isosceles trapezoid, and the cross-section of the cutting blocks 21 is a semi-ellipse. The cutting surfaces at the ends of the two cutting blocks 21 are both arc-shaped lips 1, with the middle of the arc-shaped lip 1 being higher and the left and right sides being lower.

[0025] Example 3: The number of diamond cutting tools 2 is 6. The 6 diamond cutting tools 2 are evenly arranged. The diamond cutting tools 2 are a stepped structure arranged from the inside to the outside. The upper end face (i.e. the cutting surface) of each step is an arc-shaped lip surface 1. The cross-section of the diamond cutting tool 2 is an isosceles trapezoid. The middle of the arc-shaped lip surface 1 is high, and the inner and outer sides are low.

[0026] In embodiments one to three: the end of the steel body 5 adjacent to the diamond cutting tool 2 is provided with an annular powder discharge groove 4, and the water inlet 3 is connected to the annular powder discharge groove 4.

[0027] The water inlet 3 adopts a fan-shaped water inlet. Because the fan-shaped water inlet has a large water passage area, it can fully ensure sufficient flushing flow to allow rock powder to be discharged better. At the same time, an annular powder discharge groove is also designed under the body to allow rock powder to be discharged better and prevent "drill burning".

[0028] This invention can be applied to various diamond drill bits, as long as the cutting surface is an arc-shaped lip and the arc-shaped lip is made of diamond inlaid with brazing bond. It is a universal type. Technicians can adjust the outer diameter of the drill bit and select the curvature of the lip structure of the drill bit according to the actual drilling parameters. The diamond cutting tool 2 can be designed as a flat bottom type, stepped type, arc type, sawtooth type or gear type, etc.

[0029] The specific implementation method is as follows:

[0030] The diamond used is selected from 40-60 mesh, with priority given to synthetic diamonds known for their high-temperature stability. The concentration is controlled at 50%-100% by volume. Quality requirements: diamond compressive strength ≥3000MPa, impurity content such as graphite and metal inclusions ≤0.5%, and no surface cracks or damage. Diamond surface treatment involves immersing the diamond in a mixed acid solution at room temperature for 10-15 minutes to remove surface graphite and metal impurities. It is then rinsed with deionized water until pH=7 and dried at 80-100℃ for 2 hours before use.

[0031] In this embodiment, the brazing bond is a Ni-based bond material. The Ni-based brazing filler metal composition is: Ni 70%-75%, Cr 10%-15%, B 2%-4%, and Si 3%-5%, all by mass percentage. Ni-based brazing filler metals possess specific characteristics such as good wettability with diamond, high high-temperature strength, and no harmful phase transformations. The powdered form has a particle size of 100-200 mesh, a moisture content of ≤0.2%, and is free of oxide agglomerates. Brazed diamond drill bits manufactured through a high-temperature brazing process achieve a chemical metallurgical bond between the diamond, Ni-based bond, and the metal matrix interface, exhibiting high bonding strength, a wear-resistant abrasive grain exposure height of 70%-80%, sharp cutting edge, large chip space, and resistance to clogging. With increasing rotational speed, the axial force and torque generated by the brazed diamond drill bit are less affected by changes in feed rate. It exhibits significant performance advantages under high-speed, high-feed machining conditions, resulting in a matrix with high hardness and superior wear resistance to adapt to complex stress conditions at the bottom of the hole.

[0032] The metal substrate shown in Figure 5 is made of 45# steel, with a substrate hardness controlled at HRC 20-30. Steel substrate treatment: The surface of the steel substrate must be flat, with dimensional tolerances ≤ ±0.05mm, free of pores and scratches. Subsequent cleaning requires degreasing; the substrate must be ultrasonically cleaned in an organic solvent for 15-20 minutes at 300W power and 40-50℃ to remove surface oil, followed by air drying.

[0033] The specific brazing process is as follows:

[0034] 1. Diamond Arrangement: Place the diamond particles in the brazing area of ​​the substrate, and fix them with a small amount of brazing paste / powder + organic binder, ensuring that the exposed height of the diamond is 1 / 3-1 / 2 of the particle size or completely embedded in the brazing paste layer. Clamping and Fixing: Place the substrate and diamond assembly into a graphite fixture, avoiding excessive pressure that could damage the diamonds. The gap between the fixture and the assembly should be ≤0.1mm to ensure uniform heating.

[0035] 2. Vacuum Brazing Sintering Control: Place the clamped components into a vacuum brazing furnace and evacuate to ≥5×10⁻³Pa to remove air and prevent oxidation. Heating Stage: Heating rate: 5-10℃ / min, from room temperature to 50℃ below the liquidus line of the brazing filler metal, avoiding excessively rapid heating that could cause matrix deformation. Holding Stage: Hold at 900℃ for 10-15 minutes to ensure uniform temperature distribution throughout the component. Secondary Heating Stage: Increase to the brazing temperature of 950-1050℃ for Ni-based brazing filler metal at 3-5℃ / min. Holding Stage: Hold at the brazing temperature for 15-30 minutes to ensure complete melting of the brazing filler metal and thorough wetting and diffusion with the diamond and matrix to form a metallurgical bond. Cooling Stage: Cool to below 500℃ at 5-8℃ / min, then cool to room temperature in the furnace to avoid rapid cooling causing internal stress and cracking.

[0036] 3. Subsequent Processing: Roughly grind the tool surface with a 120-180 grit grinding wheel and resin bond to remove excess filler metal. Grinding speed is 15-20 m / s, feed rate is 0.01-0.02 mm / r, to avoid damaging the diamond. Precision Calibration and Polishing: Use calipers and micrometers to measure key dimensions such as the tool's outer diameter and thickness, ensuring tolerances are ≤ ±0.02 mm. Finally, machine the drill bit's inner and outer diameters and threads on a lathe.

Claims

1. A novel diamond brazing drill bit, comprising diamond cutting tools (2), sprue (3), and a steel body (5), wherein the end of the steel body (5) is provided with a plurality of uniformly arranged diamond cutting tools (2) along the circumferential direction, and the space between two adjacent diamond cutting tools (2) is a sprue (3), characterized in that: The cutting surface at the end of the diamond cutting tool (2) is an arc-shaped lip (1); the arc-shaped lip (1) is formed by encasing diamonds in a brazing bond, which encases the diamonds inside and on the surface.

2. The novel diamond brazing drill bit according to claim 1, characterized in that: The brazing adhesive is a Ni-based adhesive material.

3. The novel diamond brazing drill bit according to claim 2, characterized in that: The diamond is a 40-60 mesh diamond.

4. A novel diamond brazing drill bit according to claim 2, characterized in that: The diamond cutting tool (2) has an isosceles trapezoidal cross section and an arc-shaped lip (1) with a high middle section and low inner and outer sides.

5. A novel diamond brazing drill bit according to claim 2, characterized in that: The diamond cutting tool (2) consists of two cutting blocks (21) and a fan-shaped base (22). The two cutting blocks (21) are symmetrically arranged on the fan-shaped base (22) at intervals. The cutting surfaces at the ends of the two cutting blocks (21) are arc-shaped lips (1), with the middle of the arc-shaped lip (1) being high and the left and right sides being low.

6. A novel diamond brazing drill bit according to claim 2, characterized in that: The diamond cutting tool (2) is a stepped structure arranged sequentially from the inside to the outside. The upper end face of each step is an arc-shaped lip (1). The middle of the arc-shaped lip (1) is high, and the inner and outer sides are low.

7. A novel diamond brazing drill bit according to any one of claims 4-6, characterized in that: The steel body (5) is provided with an annular powder discharge groove (4) at the end adjacent to the diamond cutting tool (2), and the water inlet (3) is connected to the annular powder discharge groove (4).

8. A novel diamond brazing drill bit according to claim 1 or 2, characterized in that: The water inlet (3) is a fan-shaped water inlet.

Images