Grinding wheel cutting disc for cutting medical needle and method for manufacturing the same

Abstract

This invention discloses an abrasive wheel cutting disc for cutting medical needles and its preparation method, belonging to the technical field of cutting discs. The abrasive wheel cutting disc for cutting medical needles comprises the following components by mass percentage: 30-40% green silicon carbide, 2-5% cubic boron nitride, 12-20% single-crystal corundum, 1-2.5% diamond, 4-6% quartz sand, 15-20% phenolic resin liquid, 15-20% phenolic resin powder, and 0.8-1.5% ferric oxide. The abrasive wheel cutting disc of this invention produces medical needles with a surface roughness of less than 0.02 mm, a thickness difference controlled within 0.02 mm, and a flatness within 0.1 mm, resulting in good product consistency. The cutting temperature of the abrasive wheel cutting disc of this invention is below 300℃, resulting in small cutting sparks and good heat dissipation. This prevents disc breakage during cutting of medical needles, avoids blackening of the cut end, and reduces burrs.

Description

Technical Field

[0001] This invention relates to the field of cutting disc technology, specifically to an abrasive wheel cutting disc for cutting medical needles and its preparation method. Background Technology

[0002] Because the cutting requirements for medical needles are high, existing cutting blades must be manually ground and machine-polished after cutting medical needles to achieve medical-grade quality, resulting in poor safety.

[0003] The current cutting discs used for cutting medical needles have the following problems: (1) Since the main abrasive particle size is coarse at #180, the surface roughness of the processed workpiece is greater than 0.05mm, which requires secondary manual and equipment grinding after cutting, resulting in a lot of labor costs, equipment costs, site costs, water and electricity costs, and environmental costs; (2) The cutting discs currently produced have a large thickness accuracy error of about 0.3mm and a flatness of more than 0.2mm. The size error range of the batch products after cutting is large and the product quality is inconsistent; (3) The unit price of such cutting discs produced abroad is about 15 yuan / piece, and the cutting resistance is not high. The unit price of such cutting discs produced domestically is about 3 yuan / piece. Although the cost of such cutting discs in China is lower, the cutting resistance is 1 / 5 of that of foreign ones; (4) The cutting point temperature of the cutting discs currently produced is as high as 300 degrees Celsius or more, with large sparks and poor heat dissipation, which often causes the discs to explode during cutting and will cause the product ends to turn black and have large burrs.

[0004] Therefore, how to provide a grinding wheel cutting disc for cutting medical needles has become a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the existing technology and provide an abrasive wheel cutting disc for cutting medical needles and its preparation method. The cutting precision of the abrasive wheel cutting disc of this invention can be effectively used for cutting medical needles.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A grinding wheel for cutting medical needles comprises the following components by weight percentage: 30-40% green silicon carbide, 2-5% cubic boron nitride, 12-20% single-crystal corundum, 1-2.5% diamond, 4-6% quartz sand, 15-20% phenolic resin liquid, 15-20% phenolic resin powder, and 0.8-1.5% ferric oxide.

[0008] As a preferred embodiment of the present invention, it comprises the following components in weight percentage: 32-38% green silicon carbide, 2-4% cubic boron nitride, 12-18% single crystal corundum, 1.5-2.5% diamond, 4.5-6% quartz sand, 17-20% phenolic resin liquid, 17-20% phenolic resin powder, and 0.8-1.2% ferric oxide.

[0009] As a preferred embodiment of the present invention, it comprises the following components by weight percentage: 35% green silicon carbide, 3% cubic boron nitride, 15% single crystal corundum, 2% diamond, 6% quartz sand, 19% phenolic resin liquid, 19% phenolic resin powder, and 1% ferric oxide.

[0010] In a preferred embodiment of the present invention, the green silicon carbide has a mesh size of 1000-1500 mesh; and / or

[0011] The diamond has a mesh size of 600 to 1000.

[0012] In a preferred embodiment of the present invention, the cubic boron nitride has a mesh size of 600 to 1000 mesh; and / or

[0013] The mesh size of the single-crystal corundum is 600 to 1000 mesh.

[0014] In a preferred embodiment of the present invention, the quartz sand has a mesh size of 600 to 1000 mesh; and / or

[0015] The ferric oxide has a mesh size of 200-250.

[0016] As a preferred embodiment of the present invention, the phenolic resin powder includes phenolic resin PR-50099 and phenolic resin PR-55730;

[0017] The mass ratio of phenolic resin PR-50099 to phenolic resin PR-55730 is (8-10):(7-10).

[0018] As a preferred embodiment of the present invention, the phenolic resin liquid is phenolic resin PR-940 and phenolic resin PR-51283;

[0019] The mass ratio of phenolic resin PR-940 to phenolic resin PR-51283 is (8-10):(7-10).

[0020] In a preferred embodiment of the present invention, the green silicon carbide has a mesh size of 1200.

[0021] The diamond has a mesh size of 800.

[0022] The cubic boron nitride has a mesh size of 800.

[0023] The single-crystal corundum has a mesh size of 800.

[0024] The quartz sand has a mesh size of 800.

[0025] The ferric oxide has a mesh size of 240.

[0026] This invention also provides a method for preparing an abrasive wheel cutting disc for cutting medical needles, comprising the following steps:

[0027] (1) Mix all raw materials evenly and press them into blanks;

[0028] (2) The blank is first fired at 40-55℃ for 1-4 hours, then fired at 75-90℃ for 2-6 hours, then fired at 115-125℃ for 6-10 hours, then fired at 158-175℃ for 2-5 hours, then fired at 175-190℃ for 3-6 hours, and finally fired at 210-220℃ for 2-5 hours to obtain a grinding wheel cutting disc for cutting medical needles.

[0029] The beneficial effects of the present invention are as follows: (1) The abrasive wheel cutting disc of the present invention for cutting medical needles has a surface roughness of less than 0.02 mm, a thickness difference of less than 0.02 mm, and a flatness of less than 0.1 mm, resulting in good product consistency. (2) The temperature of the cutting point of the abrasive wheel cutting disc of the present invention is below 300℃, resulting in small cutting sparks and good heat dissipation. When cutting medical needles, there will be no breakage, avoiding blackening of the cut end and reducing burrs. (3) When the abrasive wheel cutting disc of the present invention cuts medical needles, it can be formed in one step without secondary manual and equipment grinding. It can ensure that after high temperature curve hardening, the thickness accuracy of the cutting disc is controlled within ±(0.015)mm (measured at any point using a digital vernier caliper), and the flatness can be 0.05-0.1mm (the cutting disc is placed flat on marble with a flatness of less than 0.02mm after grinding, and a 0.1mm thick plug gauge is inserted between the cutting disc and the marble, and inserted around the outer circle of the cutting disc, but cannot be inserted). This results in small thickness accuracy error of the cut product and high product quality consistency. (4) The abrasive wheel cutting disc of the present invention does not require the use of glass fiber reinforced mesh and will not generate glass fiber dust during cutting, which is not harmful to human health. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0032] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0033] In this application, there are no particular restrictions on the specific dispersion and mixing methods.

[0034] Unless otherwise specified, all reagents or instruments used in this application are commercially available products.

[0035] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0036] This application provides an abrasive wheel cutting disc for cutting medical needles, comprising the following components by mass percentage: 30-40% green silicon carbide, 2-5% cubic boron nitride, 12-20% single-crystal corundum, 1-2.5% diamond, 4-6% quartz sand, 15-20% phenolic resin liquid, 15-20% phenolic resin powder, and 0.8-1.5% ferric oxide.

[0037] This invention combines the above-mentioned raw materials in a specific ratio to prepare an abrasive cutting disc that can be effectively used to cut medical needles. The surface roughness of the cut medical needles is less than 0.02 mm, the thickness difference is controlled within 0.02 mm, the flatness is within 0.1 mm, and the product consistency is good.

[0038] The temperature of the cutting point of the abrasive wheel cutting disc of the present invention is below 300°C, which reduces the amount of sparks generated during cutting and provides better heat dissipation. When cutting medical needles, the disc will not explode, and the cut end will not turn black, thus reducing burrs.

[0039] When the abrasive wheel cutting disc of this invention cuts medical needles, it can form the needles in one step without the need for secondary manual and equipment grinding. It can ensure that after high-temperature curve hardening, the thickness accuracy of the cutting disc is controlled within ±(0.015)mm (measured at any point using a digital vernier caliper), and the flatness can be achieved to 0.05-0.1mm (the cutting disc is placed flat on marble with a flatness of less than 0.02mm after grinding, and a 0.1mm thick plug gauge is inserted between the cutting disc and the marble, and then inserted around the outer circle of the cutting disc; it cannot be inserted). This results in small thickness accuracy error and high product quality consistency of the cut products.

[0040] The abrasive cutting disc of the present invention does not require the use of glass fiber reinforced mesh and will not generate glass fiber dust during cutting, which is safe for human health.

[0041] In this invention, the green silicon carbide, single-crystal corundum, and quartz sand enhance the sharpness of the cutting blade, which facilitates faster cutting of workpieces and thus improves work efficiency.

[0042] In this invention, the cutting disc incorporates single-crystal corundum, diamond, quartz sand, and calcium carbonate, which also has a cooling effect during the cutting process, reducing sparks and smoke, thus improving the surface finish of the workpiece and protecting human health.

[0043] In this invention, the addition of green silicon carbide improves cut resistance, extends service life, reduces wafer change time, and increases production efficiency.

[0044] In this invention, ferric oxide is added to enhance the wear resistance of the cutting disc, thus extending its service life.

[0045] In one embodiment, the components include the following components by weight percentage: 32–38% green silicon carbide, 2–4% cubic boron nitride, 12–18% single-crystal corundum, 1.5–2.5% diamond, 4.5–6% quartz sand, 17–20% phenolic resin liquid, 17–20% phenolic resin powder, and 0.8–1.2% ferric oxide. By controlling the raw materials within these ranges, the cutting effect is better, and the cutting accuracy is further improved.

[0046] In one embodiment, the composition includes the following components by weight percentage: 35% green silicon carbide, 3% cubic boron nitride, 15% single-crystal corundum, 2% diamond, 6% quartz sand, 19% phenolic resin liquid, 19% phenolic resin powder, and 1% ferric oxide.

[0047] In one embodiment, the green silicon carbide has a mesh size of 1000-1500 mesh and / or

[0048] The diamond has a mesh size of 600 to 1000.

[0049] In one embodiment, the cubic boron nitride has a mesh size of 600 to 1000 mesh; and / or

[0050] The mesh size of the single-crystal corundum is 600 to 1000 mesh.

[0051] In one embodiment, the quartz sand has a mesh size of 600 to 1000 mesh; and / or

[0052] The ferric oxide has a mesh size of 200-250.

[0053] In one embodiment, the phenolic resin powder includes phenolic resin PR-50099 and phenolic resin PR-55730.

[0054] The mass ratio of phenolic resin PR-50099 to phenolic resin PR-55730 is (8-10):(7-10).

[0055] Among them, phenolic resin PR-50099 is a phenolic resin powder containing hexamine (hexamethylenetetramine). The hexamine content in phenolic resin PR-50099 is 9%, and phenolic resin PR-50099 belongs to high molecular weight phenolic resin powder.

[0056] Among them, phenolic resin PR-55730 is a phenolic resin powder containing hexamine (hexamethylenetetramine). The hexamine content in phenolic resin PR-55730 is 7%, and phenolic resin PR-55730 belongs to medium molecular weight phenolic resin powder.

[0057] This invention utilizes phenolic resin powder containing hexamine and with different molecular weights, as well as different flow properties, to effectively balance durability and machinability. It also exhibits good mixing with the cutting particles, excellent compatibility, and workability. When used in combination, the two significantly improve cutting accuracy.

[0058] In one embodiment, the phenolic resin liquid is phenolic resin PR-940 and phenolic resin PR-51283;

[0059] The mass ratio of phenolic resin PR-940 to phenolic resin PR-51283 is (8-10):(7-10).

[0060] Among them, phenolic resin PR-940 and phenolic resin PR-51283 have good grain wettability when applied, and their compatibility with powdered phenolic resin is good. Therefore, the grain compactness is good, the durability of the grinding wheel is improved, and they have good compatibility with the above-mentioned phenolic resin powder.

[0061] Therefore, this invention comprehensively improves the sharpness, cut resistance, cutting temperature, cutting efficiency, and cutting accuracy of the cutting disc by configuring specially formulated resin liquid and resin powder.

[0062] In one embodiment, the green silicon carbide has a mesh size of 1200.

[0063] The diamond has a mesh size of 800.

[0064] The cubic boron nitride has a mesh size of 800.

[0065] The single-crystal corundum has a mesh size of 800.

[0066] The quartz sand has a mesh size of 800.

[0067] The ferric oxide has a mesh size of 240.

[0068] The effect is better when the mesh size of each raw material is controlled within this range.

[0069] One embodiment of the present invention provides a method for preparing an abrasive wheel cutting disc for cutting medical needles, comprising the following steps:

[0070] (1) Mix all raw materials evenly and press them into blanks;

[0071] (2) The blank is first fired at 40-55℃ for 1-4 hours, then fired at 75-90℃ for 2-6 hours, then fired at 115-125℃ for 6-10 hours, then fired at 158-175℃ for 2-5 hours, then fired at 175-190℃ for 3-6 hours, and finally fired at 210-220℃ for 2-5 hours to obtain a grinding wheel cutting disc for cutting medical needles.

[0072] The following embodiments are provided to facilitate understanding of the invention. These embodiments are not intended to limit the scope of the claims.

[0073] Example 1

[0074] The raw materials and types used in the embodiments and comparative examples of this application are shown in Table 1 below.

[0075] Table 1

[0076]

[0077]

[0078] The raw material proportions for Examples 1 to 7 are shown in Table 2, and the raw material proportions for Comparative Examples 1 to 6 are shown in Table 3 (where all figures in Tables 2 and 3 are parts by weight).

[0079] The preparation methods of the abrasive wheel cutting discs in Examples 1-7 and Comparative Examples 1-5 all include the following steps:

[0080] (1) Mix green silicon carbide, cubic boron nitride, single crystal corundum, diamond and quartz sand evenly, then add phenolic resin powder and phenolic resin liquid and mix evenly. Press at 8 MPa pressure and 80℃ for 30s to obtain billet.

[0081] (2) The blank is placed in a hardening furnace for firing. First, it is fired at 80°C for 4 hours, then at 110°C for 7 hours, then at 150°C for 5 hours, then at 180°C for 5 hours, and finally at 210°C for 4 hours to obtain a grinding wheel cutting disc for cutting medical needles.

[0082] Table 2

[0083]

[0084]

[0085] Table 3

[0086]

[0087]

[0088] Test case

[0089] Cutting experiments were conducted on the abrasive wheel cutting discs obtained in Examples 1-3 and Comparative Examples 1-6. The discs were mounted on a cutting machine with a rotation speed of 3500 r / min and a cutting pressure of 50 N. The workpieces to be cut were medical needles. Twenty discs were cut for each example and comparative example, and the average value was calculated.

[0090] Performance testing

[0091] 1. Use a digital vernier caliper to measure the thickness accuracy of the cutting disc at any 10 different points. The thickness difference at different points in this application needs to be controlled within ±(0.02) mm. The results are shown in Table 4.

[0092] 2. Place the cutting disc flat on a marble surface with a flatness of less than 0.02mm after polishing. Use plug gauges of different thicknesses to insert between the cutting disc and the marble surface, and insert them around the outer circle of the cutting disc. If none of them can be inserted, then the flatness of the cutting disc is determined to be within the required thickness. The results are shown in Table 4.

[0093] 3. Surface roughness of workpiece: After cutting, a diamond stylus with a tip curvature radius of about 2 micrometers is used to slowly slide along the surface of the workpiece to be measured using a handheld or benchtop roughness measuring instrument. The surface roughness value is obtained by measuring the vertical displacement of the diamond stylus. The results are shown in Table 4.

[0094] Table 4

[0095]

[0096]

[0097] As can be seen from Table 1, the abrasive wheel cutting disc for medical needles of the present invention has excellent cutting precision. The surface roughness of the cut medical needles is less than 0.02 mm, the thickness difference is controlled within 0.02 mm, the flatness is within 0.1 mm, and the product consistency is good.

[0098] Example 1 is the best implementation of the present invention, which has the best cutting precision and can greatly improve the cutting accuracy, so that the cut medical needles do not need to be processed again.

[0099] As can be seen from the comparison between Example 1 and Comparative Examples 1 and 2, when the abrasive wheel cutting disc of the present invention is used to cut medical needles, the amount of each raw material added needs to be strictly controlled. If the amount of raw material is not within the scope of the present invention, the cutting accuracy will be significantly reduced.

[0100] Comparing Example 1 with Comparative Examples 2-5, it can be seen that in the present invention, phenolic resin PR-50099 and phenolic resin PR-55730 need to be added to the phenolic resin powder to achieve the excellent effect of the present invention. If a similar phenolic resin PR-50869B (with excessive hexamine content and small molecular weight) is used instead, the effect will also decrease.

[0101] Comparing Example 1 and Comparative Example 6, it can be seen that the present invention uses a combination of phenolic resin PR-940 and phenolic resin PR-51283, which can further improve the effect.

[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A grinding wheel cutting disc for cutting medical needles, characterized in that, It includes the following components by mass percentage: 30-40% green silicon carbide, 2-5% cubic boron nitride, 12-20% single crystal corundum, 1-2.5% diamond, 4-6% quartz sand, 15-20% phenolic resin liquid, 15-20% phenolic resin powder, and 0.8-1.5% ferric oxide. The phenolic resin powder includes phenolic resin PR-50099 and phenolic resin PR-55730; the mass ratio of phenolic resin PR-50099 to phenolic resin PR-55730 is (8~10):(7~10). The phenolic resin solution includes phenolic resin PR-940 and phenolic resin PR-51283; the mass ratio of phenolic resin PR-940 to phenolic resin PR-51283 is (8~10):(7~10).

2. The abrasive wheel cutting disc for cutting medical needles according to claim 1, characterized in that, It includes the following components by mass percentage: 32-38% green silicon carbide, 2-4% cubic boron nitride, 12-18% single crystal corundum, 1.5-2.5% diamond, 4.5-6% quartz sand, 17-20% phenolic resin liquid, 17-20% phenolic resin powder, and 0.8-1.2% ferric oxide.

3. The abrasive wheel cutting disc for cutting medical needles according to claim 1, characterized in that, The composition includes the following components by weight percentage: 35% green silicon carbide, 3% cubic boron nitride, 15% single-crystal corundum, 2% diamond, 6% quartz sand, 19% phenolic resin liquid, 19% phenolic resin powder, and 1% ferric oxide.

4. The abrasive wheel cutting disc for cutting medical needles according to claim 1, characterized in that, The green silicon carbide has a mesh size of 1000-1500 mesh; and / or The diamond has a mesh size of 600-1000.

5. The abrasive wheel cutting disc for cutting medical needles according to claim 1, characterized in that, The cubic boron nitride has a mesh size of 600-1000 mesh; and / or The mesh size of the single-crystal corundum is 600~1000 mesh.

6. The abrasive wheel cutting disc for cutting medical needles according to claim 1, characterized in that, The quartz sand has a mesh size of 600-1000 mesh; and / or The ferric oxide has a mesh size of 200-250.

7. The abrasive wheel cutting disc for cutting medical needles according to any one of claims 1 to 6, characterized in that, The green silicon carbide has a mesh size of 1200. The diamond has a mesh size of 800. The cubic boron nitride has a mesh size of 800. The single-crystal corundum has a mesh size of 800. The quartz sand has a mesh size of 800. The ferric oxide has a mesh size of 240.

8. The method for preparing the abrasive wheel cutting disc for cutting medical needles according to any one of claims 1 to 7, characterized in that, Includes the following steps: (1) Mix all raw materials evenly and press them into blanks; (2) The blank is first fired at 40~55℃ for 1~4h, then fired at 75~90℃ for 2~6h, then fired at 115~125℃ for 6~10h, then fired at 158~175℃ for 2~5h, then fired at 175~190℃ for 3~6h, and finally fired at 210~220℃ for 2~5h to obtain a grinding wheel cutting disc for cutting medical needles.

Images