A water gap processing technique for hot-pressed diamond impregnated drill bits

Abstract

The present application relates to a kind of water gap processing technology of hot-pressing diamond impregnated drill bit, belong to the technical field of drilling tool manufacturing.The technical scheme is: water gap material powder is loaded in the graphite mould at water gap position, diamond powder is filled in the graphite mould at impregnated block position, after the steel body of drill bit is loaded into graphite mould, the assembled graphite mould is sent into medium frequency electric furnace to be sintered into drill bit matrix by hot-pressing;The water gap material powder is metal alloy powder, the metal alloy powder is the mixed powder of Fe and Cu, wherein Fe accounts for 90% by mass ratio, and Cu accounts for 10% by mass ratio;The water gap material powder between adjacent two impregnated blocks on drill bit matrix is removed by diamond brazing saw blade grinding, and the water gap of drill bit is processed.The present application uses metal alloy powder to replace graphite to fill the space between adjacent two impregnated blocks, uses numerical control milling machine to process the water gap of drill bit with diamond brazing saw blade, improves production efficiency, reduces labor intensity, and is safe and environmentally friendly.

Description

TECHNICAL FIELD

[0001] The present application relates to a water gap processing technology of hot-pressing impregnated diamond drill bit, belonging to the technical field of drilling tool manufacturing. BACKGROUND

[0002] The impregnated diamond drill bit is generally composed of a drill bit steel body, an impregnated matrix and a water gap. The end of the drill bit steel body is provided with a plurality of impregnated matrices arranged at intervals. The space between two adjacent impregnated matrices is called a water gap, which includes a main water gap at the upper part and a side water gap corresponding to the lower part of the main water gap. The existing technology hot-pressing impregnated diamond drill bit processing process is as follows: after the designed and processed graphite mold is assembled, graphite is filled as water gap powder at the position of the water gap, and diamond powder is filled at the position of the impregnated matrix. After the drill bit steel body is filled, the assembled graphite mold is sent into a medium frequency electric furnace for hot-pressing sintering to form a drill bit matrix. After forming, the graphite filled between the two adjacent impregnated matrices on the drill bit matrix needs to be removed to become a diamond drill bit. The position where the graphite is removed is the water gap. Since graphite is easy to remain, the existing technology adopts manual method to remove the graphite to form the water gap, which has the problems of high labor intensity, high risk coefficient, low production efficiency, and graphite as water gap powder itself also pollutes the environment. In addition, the flowability of graphite in the sintering process is poor, which has an adverse effect on the internal quality of the product. SUMMARY

[0003] The present application aims to provide a water gap processing technology of hot-pressing impregnated diamond drill bit, which uses metal alloy powder instead of graphite as water gap powder to fill the space between two adjacent impregnated matrices, and uses a numerical control milling machine to cooperate with a diamond brazing saw blade to grind the water gap of the drill bit, so as to improve the production efficiency, reduce the labor intensity, be safe and environmentally friendly, and solve the above-mentioned problems existing in the background technology.

[0004] The technical scheme of the present application is as follows:

[0005] A water gap processing technology of hot-pressing impregnated diamond drill bit, water gap powder is filled at the position of the water gap in the graphite mold, diamond powder is filled at the position of the impregnated matrix in the graphite mold, and after the drill bit steel body is filled into the graphite mold, the assembled graphite mold is sent into a medium frequency electric furnace for hot-pressing sintering to form a drill bit matrix. The water gap powder is metal alloy powder, and the metal alloy powder is a mixture of Fe and Cu, wherein the mass ratio of Fe is 90% and the mass ratio of Cu is 10%. The water gap powder between two adjacent impregnated matrices on the drill bit matrix is removed by grinding with a diamond brazing saw blade, and the water gap of the drill bit is processed.

[0006] Further, the water gap processed by the diamond brazing saw blade is a main water gap and a side water gap, the main water gap is processed first and then the side water gap is processed; the process of processing the main water gap is that the diamond brazing saw blade is located above the main water gap position of the drill bit matrix, the diamond brazing saw blade moves downward, grinding starts from the upper cutter position of the diamond saw blade, after the lowest point of the diamond brazing saw blade reaches the bottom surface of the main water gap, the diamond brazing saw blade moves forward and backward to complete one grinding, the width of the grinding is the thickness of the diamond brazing saw blade; then the diamond brazing saw blade moves horizontally to repeat the next grinding, and so on, until the grinding of the main water gap is completed; the process of processing the side water gap is that the diamond brazing saw blade is located above the side water gap position of the side surface of the drill bit matrix, the diamond brazing saw blade moves downward according to the bottom surface shape of the side water gap, one grinding is completed, the width of the grinding is the thickness of the diamond brazing saw blade; then the diamond brazing saw blade moves horizontally to repeat the next grinding, and so on, until the grinding of the side water gap is completed.

[0007] Further, the diamond brazing saw blade is installed on a numerical control milling machine, and the main water gap and the side water gap are automatically ground through a control program.

[0008] Further, the water gap material powder is cold-pressed into shape in a graphite mold after an adhesive is added, the adhesive is white latex, and the mass ratio of the adhesive added to the total mass of the water gap material powder is 1%.

[0009] Further, the diamond brazing saw blade is an annular piece composed of a steel body and a diamond coating, the steel body is annular, the inner ring of the steel body is an inner ring hole, and the diamond coating is coated on the outer ring of the steel body to form a working surface.

[0010] Further, the diamond coating is formed by brazing and sintering of 50-60 mesh diamonds and the steel body, the thickness of the diamond coating on the two side surfaces of the outer ring of the steel body is 1mm more than the thickness of the steel body, which is beneficial to the depth requirement of the diamond brazing saw blade 10 when grinding the water gap of the drill bit matrix.

[0011] The present application uses metal alloy powder instead of graphite to fill the space between adjacent two impregnated matrix blocks, which can make the drill bit matrix firmly bonded and provide convenience for subsequent water gap processing and grinding.

[0012] The present application has the following beneficial effects: the metal alloy powder is used to replace graphite to fill the space between adjacent two impregnated matrix blocks, a numerical control milling machine is used to process the water gap of the drill bit together with the diamond brazing saw blade, the production efficiency is improved, the labor intensity is reduced, and the safety and environmental protection are achieved; the metal alloy powder has good fluidity during sintering, and the internal sintering quality of the product is ensured. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 It is a structure perspective view of the embodiment of the present application impregnated diamond drill bit;

[0014] Figure 2 Structure sectional view of the diamond-impregnated drill bit of the embodiment of the present application;

[0015] Figure 3 Structure sectional view of the diamond-impregnated drill bit of the embodiment of the present application; Figure 2 Bottom view of the diamond-impregnated drill bit of the embodiment of the present application;

[0016] Figure 4 Structure sectional view of the diamond-impregnated drill bit of the embodiment of the present application;

[0017] Figure 5 Structure sectional view of the diamond-impregnated drill bit of the embodiment of the present application;

[0018] Figure 6 Structure sectional view of the diamond-impregnated drill bit of the embodiment of the present application;

[0019] In the figure: main water gap 1, side water gap 2, impregnated block 3, drill steel body 4, steel body 5, diamond coating 6, diamond saw blade upper knife position 7, inner ring hole 8, locking nut 9, diamond brazing saw blade 10, transmission center shaft 11, transmission bearing seat 12, drill block 13, transmission pulley 14. DETAILED DESCRIPTION

[0020] The present application will be further described by examples in combination with the accompanying drawings.

[0021] Referring to the accompanying drawings Figures 1-5 A water gap processing technology using hot-pressed diamond-impregnated drill bit, water gap material powder is loaded at the water gap position in the graphite mold, diamond powder is filled at the impregnated block position in the graphite mold, after the drill steel body 4 is loaded into the graphite mold, the assembled graphite mold is sent into the medium-frequency electric furnace to be hot-pressed and sintered to form the drill block 13; the water gap material powder is metal alloy powder, the metal alloy powder is a mixture of Fe and Cu, wherein Fe accounts for 90% of the mass ratio and Cu accounts for 10% of the mass ratio; the diamond brazing saw blade 10 is used to grind and remove the water gap material powder between the adjacent two impregnated blocks 3 on the drill block 13 to process the water gap of the drill bit.

[0022] The diamond brazing saw blade 10 processes the water gap into a main water gap 1 and a side water gap 2, and the main water gap 1 is processed first and then the side water gap 2; the process of processing the main water gap 1 is as follows: the diamond brazing saw blade 10 is located above the main water gap position of the drill bit matrix, the diamond brazing saw blade 10 moves downward, and the grinding starts from the upper cutter position 7 of the diamond saw blade; after the lowest point of the diamond brazing saw blade 10 reaches the bottom surface of the main water gap 1, the diamond brazing saw blade 10 moves forward and backward to complete a grinding, and the grinding width is the thickness of the diamond brazing saw blade 10; then the diamond brazing saw blade 10 moves transversely to repeat the next grinding, and so on, until the grinding of the main water gap 1 is completed; the process of processing the side water gap 2 is as follows: the diamond brazing saw blade 10 is located above the side water gap position of the side surface of the drill bit matrix, the diamond brazing saw blade 10 moves downward according to the bottom surface shape of the side water gap 2, and a grinding is completed, and the grinding width is the thickness of the diamond brazing saw blade 10; then the diamond brazing saw blade 10 moves transversely to repeat the next grinding, and so on, until the grinding of the side water gap 2 is completed.

[0023] Preferably, the diamond brazing saw blade 10 is installed on a numerical control milling machine, and the main water gap 1 and the side water gap 2 are automatically ground by controlling the program.

[0024] Preferably, the water gap powder is cold-pressed into a graphite mold after adding a bonding agent, the bonding agent is white latex, and the mass ratio of the bonding agent added to the total mass of the water gap powder is 1%. In the embodiment, the water gap powder is cold-pressed into the graphite mold by a jig under a pressure of 10 MPa.

[0025] Sintering is performed by automatic hot pressing and medium frequency sintering at a high temperature of 1020 degrees, and the hardness of the water gap position on the drill bit matrix 13 after sintering is HRC18.

[0026] Referring to the accompanying drawings, Figure 4 The diamond brazing saw blade 10 is an annular piece composed of a steel body 5 and a diamond coating 6, the steel body 5 is annular, the inner ring of the steel body 5 is an inner ring circular hole 8, and the diamond coating 6 is coated on the outer ring of the steel body 5 to form a working surface.

[0027] The diamond coating 6 is sintered by brazing 50-60 mesh diamonds and the steel body 5, and the thickness of the diamond coating 6 on the two sides of the outer ring of the steel body 5 is 1 mm more than the thickness of the steel body 5, which is beneficial to the cooling of the steel body 5 when the diamond brazing saw blade 10 cuts the water gap, and can also meet the requirements of various water gap depths. Preferably, the thickness of the diamond is 5 mm, and the length is 10 mm, which can meet the requirements of diamond drill bit water gap cutting.

[0028] In the embodiment, as shown in Figure 1 and Figure 2 The purpose of the present application is to solve Figure 1 and Figure 2The processing of the main water inlet 1 and the side water inlet 2 shown in the figure requires opening corresponding water channel positions on the drill bit body 13 to ensure the normal use of the hot-pressed impregnated diamond drill bit.

[0029] Figure 4 The diamond brazed saw blade 10 used in this invention has a steel body 5 made of 42CrMo material to ensure rigidity and strength after sintering. The inner ring hole 8 in the middle of the steel body 5 is a clamping position for the CNC milling machine, where the diamond brazed saw blade 10 is installed. The diamond coating 6 is formed by brazing and sintering 50-60 mesh diamond with the steel body 5. The brazing and sintering process is a well-known and commonly used process in the art.

[0030] like Figure 5 As shown, the diamond coating 6 is also the working surface of the diamond brazed saw blade 10.

[0031] like Figure 6 As shown, diamond brazed saw blades 10 are respectively clamped at both ends of the transmission center shaft 11 of the CNC milling machine and locked by locking nuts 9. The transmission center shaft 11 is mounted on the transmission bearing seat 12, and a transmission pulley 14 is provided on the transmission center shaft 11. The diamond brazed saw blades 10 on both sides can operate synchronously to process the sprue on the two drill bit bodies 13 at the same time, thereby improving processing efficiency.

[0032] Detailed operation steps:

[0033] a. Prepare sprue powder by mixing Fe and Cu, wherein Fe accounts for 90% by mass and Cu accounts for 10% by mass; after adding the binder, the binder is white glue, and the mass ratio of the binder added is 1% of the total mass of the sprue powder;

[0034] b. After assembling the designed and processed graphite mold, put the sprue material powder into the sprue position and cold press it into the graphite mold under a pressure of 10 MPa.

[0035] c. Fill the graphite mold with diamond powder at the position of the embedded matrix block. After the drill bit steel body 4 is installed, send the assembled graphite mold into the medium frequency electric furnace for hot pressing and sintering to form the drill bit matrix 13. Sinter at a high temperature of 1020 degrees. After sintering, the hardness of the upper gate position of the drill bit matrix 13 is HRC18.

[0036] d. Prepare diamond brazed saw blade 10. The diamond brazed saw blade 10 is an annular blade composed of a steel body 5 and a diamond coating 6. The steel body 5 is annular, and the inner ring of the steel body 5 is an inner ring circular hole 8. The diamond coating 6 is coated on the outer ring of the steel body 5 to form a working surface. The diamond coating 6 is formed by brazing and sintering 50-60 mesh diamond with the steel body 5. The thickness of the diamond coating 6 on both sides of the outer ring of the steel body 5 exceeds the thickness of the steel body 5 by 1 mm. The outer diameter of the diamond brazed saw blade 10 is 80 mm.

[0037] e. Installing the diamond brazed saw blade 10 on the numerical control milling machine through the clamp;

[0038] f. Using 1200 rpm to grind the main water port 1 and the side water port 2 of the drill body 13 in turn;

[0039] g. During the grinding process, cutting fluid is introduced to cool the drill body 13 and the diamond brazed saw blade 10, reducing the damage of high temperature to the diamond.

[0040] Using a diamond brazed saw blade 10 with an outer diameter of 80 mm, the same diamond brazed saw blade 10 can be used to process the main water port 1 and the side water port 2 during the numerical control milling process, avoiding subsequent separate processing of the side water port 2.

Claims

1. A process for machining the sprue of a hot-pressed impregnated diamond drill bit, characterized in that: Sprue material powder is inserted into the sprue position of the graphite mold. After adding a binder, the sprue material powder is cold-pressed into the graphite mold under a pressure of 10 MPa. Diamond powder is filled into the impregnated matrix (3) position of the graphite mold. After the drill bit steel body (4) is inserted into the graphite mold, the assembled graphite mold is sent into a medium-frequency electric furnace for hot pressing and sintering to form the drill bit matrix (13). Sintering is carried out at a high temperature of 1020 degrees Celsius. After sintering, the hardness of the sprue position on the drill bit matrix (13) is HRC. 18; Prepare sprue powder, wherein the sprue powder is a metal alloy powder, and the metal alloy powder is a mixture of Fe and Cu powder, wherein Fe and Cu are mixed, wherein Fe accounts for 90% by mass and Cu accounts for 10% by mass; the binder is white latex, and the binder is added at a mass ratio of 1% of the total mass of the sprue powder; the sprue powder between two adjacent impregnated blocks (3) is removed by grinding on the drill bit body (13) with a diamond brazed saw blade (10) to process the sprue of the drill bit; The sprues processed by the diamond brazed saw blade (10) are the main sprue (1) and the side sprue (2). The main sprue (1) is processed first, followed by the side sprue (2). The process of processing the main sprue (1) is as follows: the diamond brazed saw blade (10) is positioned above the main sprue position on the drill bit body. The diamond brazed saw blade (10) moves downward and begins grinding from the upper cutting position (7) of the diamond saw blade. After the lowest point of the diamond brazed saw blade (10) reaches the bottom surface of the main sprue (1), the diamond brazed saw blade (10) is moved back and forth to complete one grinding cycle. The width of the ground part is the width of the diamond brazed saw blade (1). 0) Thickness; then move the diamond brazed saw blade (10) laterally to repeat the next grinding, and so on, until the grinding of the main gate (1) is completed; the process of processing the side gate (2) is as follows: the diamond brazed saw blade (10) is located above the side gate position on the side of the drill bit body, and the diamond brazed saw blade (10) is moved downward according to the bottom shape of the side gate (2) to complete one grinding, and the width ground is the thickness of the diamond brazed saw blade (10); then move the diamond brazed saw blade (10) laterally to repeat the next grinding, and so on, until the grinding of the side gate (2) is completed.

2. The sprue machining process for a hot-pressed impregnated diamond drill bit according to claim 1, characterized in that: The diamond brazed saw blade (10) is installed on a CNC milling machine and automatically grinds out the main water inlet (1) and the side water inlet (2) through a control program.

3. The sprue machining process for a hot-pressed impregnated diamond drill bit according to claim 2, characterized in that: The diamond brazed saw blade (10) is an annular blade composed of a steel body (5) and a diamond coating (6). The steel body (5) is annular, and the inner ring of the steel body (5) is an inner ring circular hole (8). The diamond coating (6) is coated on the outer ring of the steel body (5) to form a working surface.

4. The sprue machining process for a hot-pressed impregnated diamond drill bit according to claim 3, characterized in that: The diamond coating (6) is formed by brazing and sintering 50-60 mesh diamond with the steel body (5). The thickness of the diamond coating (6) on both sides of the outer ring of the steel body (5) exceeds the thickness of the steel body (5) by 1 mm.

Images