Efficient double-end-face grinding wheel for gear grinding and preparation method of efficient double-end-face grinding wheel

Abstract

The invention provides a gear efficient grinding double-end-face grinding wheel and a preparation method, the double-end-face grinding wheel comprises a base body and a grinding material layer arranged on the base body, and the grinding material layer comprises, by weight, 30%-45% of CBN grinding materials, 25%-30% of phenolic resin powder, 20%-25% of silicon carbide, 2%-5% of chromic oxide, 2%-5% of zinc oxide, 2%-5% of aluminum oxide hollow balls and 1%-2% of glass beads. According to the double-end-face grinding wheel, the pore structure combining the large pores and the micro pores is adopted, the grinding efficiency is improved, and the workpiece burning problem is reduced; and meanwhile, the flatness of the ground workpiece can reach 0.003 mm, the surface roughness Ra of the ground workpiece is 0.4, the surface quality of the ground workpiece is good, and the grinding process is stable.

Description

Technical Field

[0001] The invention relates to the technical field of grinding wheel preparation, in particular to a double-end-face grinding wheel for high-efficiency grinding of gears and a preparation method thereof. Background Art

[0002] With the continuous development of new energy vehicles, the amount of gears used is increasing, and the high speed and high torque of new energy vehicle motors have put forward higher requirements on the precision and wear resistance of traditional gears. Gears are mostly made of high-strength steel, carburized and quenched steel and other materials. These materials have excellent toughness, fatigue strength and wear resistance, which also requires higher performance requirements for grinding tools.

[0003] Double-face grinding is a processing technology that can grind two parallel end faces of a workpiece at the same time. By grinding the two sides of the workpiece simultaneously with two grinding heads, the parallelism, dimensional accuracy and surface quality of the workpiece can be precisely processed. Therefore, the double-face grinding method can efficiently process the end face of the gear while maintaining the high precision of the gear end face. However, the high hardness and high strength of the gear material make it a typical difficult-to-process material, and the existing double-face grinding wheels have the following problems: 1. The flatness and roughness of the workpiece after grinding do not meet the standards; 2. The grinding efficiency is low, and the workpiece is easily burned during the grinding process. Therefore, the present invention designs a double-face grinding wheel for efficient gear grinding, which can efficiently grind gear materials. Summary of the invention

[0004] The present invention proposes a double-end grinding wheel for high-efficiency gear grinding and a preparation method thereof, which adopts a pore structure combining large pores and micropores to improve grinding efficiency and reduce the occurrence of workpiece burning problems; at the same time, the flatness of the workpiece after grinding can reach 0.003mm, the surface roughness of the workpiece after grinding is Ra0.4, the surface quality after grinding is good, and the grinding process is stable.

[0005] The technical solution of the present invention is achieved as follows: a double-end grinding wheel for high-efficiency grinding of gears comprises a substrate and an abrasive layer arranged on the substrate, wherein the abrasive layer comprises the following raw materials in weight percentage: 30-45% CBN abrasive, 25-30% phenolic resin powder, 20-25% silicon carbide, 2-5% chromium oxide, 2-5% zinc oxide, 2-5% aluminum oxide hollow balls and 1-2% glass microbeads.

[0006] Furthermore, the particle size of the CBN abrasive is 100 / 120-170 / 200, the particle size of the silicon carbide is F400-F1200, the particle size of the alumina hollow sphere is 1.5-2 mm, and the particle size of the glass microbead is 90-110 μm.

[0007] For particle sizes of 100 / 120 to 170 / 200, refer to the national standard GB / T 6406-1996. The particle size of 100 / 120 corresponds to the particle size of 150 / 125μm, and the particle size of 170 / 200 corresponds to the particle size of 90 / 75μm. For particle sizes of F400 to F1200, refer to the provisions of GB / T 2481.2-2009. The particle size of F400 corresponds to the particle size of d s50 The median particle size is 17.3 ± 1.0 μm, and the corresponding d s50 The median particle size was 3.0±0.5 μm.

[0008] Furthermore, vertical grooves are evenly distributed along the circumferential direction on the abrasive layer, and a single vertical groove is arranged along the radial direction. The abrasive layer is also provided with coaxial annular grooves, and the width of the vertical grooves and the annular grooves is 2-3 mm.

[0009] A method for preparing a double-end grinding wheel for high-efficiency gear grinding comprises the following steps:

[0010] (1) CBN abrasive, phenolic resin powder, silicon carbide, chromium oxide, zinc oxide and glass micro beads are weighed according to a ratio, and then put into a mixing barrel, and mixed by a three-dimensional mixer for 4 to 8 hours to make the powders uniformly mixed, and then hollow alumina balls are mixed and mixed uniformly to obtain a mixture;

[0011] (2) After the mixed material is thrown on the substrate and scraped flat, it is pressed into an abrasive layer by a hot pressing method to obtain a prefabricated grinding wheel;

[0012] (3) curing the prefabricated grinding wheel;

[0013] (4) After curing, the grinding wheel is processed by a CNC lathe to the required grinding wheel size accuracy, and the grinding wheel surface edge is opened by a grinder to obtain a double-end CBN grinding wheel for gear grinding.

[0014] Furthermore, in step (2), the hot pressing method is as follows: the hot pressing temperature is 180° C., after the mixed material is leveled, the upper press is preheated for 3 to 5 minutes, vented 5 to 10 times, fixed molded, and pressed for 120 to 180 minutes.

[0015] Furthermore, in step (3), the curing process is: 40-60°C, curing for 1-2 hours; 70-90°C, curing for 2-4 hours; 100-120°C, curing for 2-4 hours; 130-150°C, curing for 2-4 hours; 160-190°C, curing for 8-12 hours.

[0016] Furthermore, in step (3), vertical grooves and annular grooves are firstly formed in the abrasive layer of the prefabricated grinding wheel, and then cured.

[0017] Beneficial effects of the present invention:

[0018] The gear high-efficiency grinding double-end face grinding wheel of the present invention adopts a pore structure combining large pores and micropores to improve grinding efficiency and reduce the occurrence of workpiece burning problems; during the grinding process, the large pores are used for chip melting and chip removal to reduce grinding heat; the micropores increase the self-sharpening property of the abrasive and comprehensively improve the grinding performance of the grinding wheel.

[0019] The gear high-efficiency grinding double-end face grinding wheel of the present invention has an abrasive layer with a slotted structure, and an annular groove is added on the basis of the vertical groove, so as to improve the chip removal capacity of the grinding wheel during grinding.

[0020] The double-end face grinding wheel for high-efficiency gear grinding of the present invention can grind gear materials with high efficiency by improving the raw materials of the abrasive layer and the proportion thereof. The flatness of the workpiece after grinding can reach 0.003 mm, the surface roughness of the workpiece after grinding is Ra0.4, the surface quality after grinding is good, and the grinding process is stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic diagram of the structure of the double-end surface CBN grinding wheel for high-efficiency gear grinding of the present invention. DETAILED DESCRIPTION

[0023] 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.

[0024] Example 1

[0025] A double-end grinding wheel for high-efficiency gear grinding Figure 1As shown, it is composed of an abrasive layer 1 and a substrate 2, the substrate 2 is an aluminum substrate, and the abrasive layer 1 has a vertical groove 3 and an annular groove 4 structure. The grinding wheel specification is 585*65*50*195*7. The abrasive layer 1 is composed of CBN abrasive, phenolic resin powder, silicon carbide, chromium oxide, zinc oxide, hollow aluminum oxide balls, and glass microspheres. Among them, the CBN abrasive particle size is 100 / 120, the silicon carbide particle size is F400, the hollow aluminum oxide ball particle size is 1.5-2mm, and the glass microsphere particle size is 90-110μm. The total weight ratio of the grinding wheel formula is 100%, and the distribution ratio of its components is: 30% CBN abrasive, 30% phenolic resin powder, 25% silicon carbide, 5% chromium oxide, 5% zinc oxide, 4% hollow aluminum oxide balls and 1% glass microspheres.

[0026] The preparation steps of the grinding wheel are as follows:

[0027] (1) CBN, phenolic resin powder, silicon carbide, chromium oxide, zinc oxide, glass microspheres, etc. are weighed according to a proportion and placed in a mixing barrel, and mixed by a three-dimensional mixer for 8 hours to make the powders uniformly mixed; then hollow alumina balls are mixed in, and after mixing uniformly, a mixture is obtained;

[0028] (2) The grinding wheel is prepared by hot pressing at a temperature of 180°C. Prepare the mold, then put the mixture into the mold frame, scrape the mixture flat on the substrate, put it into the press, preheat for 3 to 5 minutes, exhaust 5 to 10 times, fix the mold, and press for 120 minutes;

[0029] (3) The pressed grinding wheel is slotted with a slotting device to form 16 vertical slots 3 and 1 annular slot 4, with a slot width of 2 to 3 mm;

[0030] Put the slotted grinding wheel into the oven for curing. The curing process is 50℃ for 2h, 70℃ for 2h, 90℃ for 2h, 110℃ for 2h, 130℃ for 2h, 150℃ for 2h, 170℃ for 2h, and 180℃ for 10h.

[0031] (4) After curing, the grinding wheel is processed by a CNC lathe to the grinding wheel size accuracy, and the grinding wheel surface edge is opened by a grinder to obtain a gear grinding double-end grinding wheel.

[0032] Example 2

[0033] A double-end grinding wheel for high-efficiency grinding of gears has a specification of 585*65*50*195*7. Abrasive layer 1 is composed of CBN abrasive, phenolic resin powder, silicon carbide, chromium oxide, zinc oxide, hollow aluminum oxide balls, and glass microspheres. The CBN abrasive particle size is 100 / 120, the silicon carbide particle size is F400, the hollow aluminum oxide ball particle size is 1.5-2mm, and the glass microsphere particle size is 90-110μm. The total weight ratio of the grinding wheel formula is 100%, and the distribution ratio of its components is: 38% CBN abrasive, 28% phenolic resin powder, 20% silicon carbide, 4% chromium oxide, 4% zinc oxide, 4% hollow aluminum oxide balls, and 2% glass microspheres.

[0034] The preparation steps of the grinding wheel are the same as those in Example 1.

[0035] Example 3

[0036] A double-end grinding wheel for high-efficiency gear grinding Figure 1 As shown, the grinding wheel specification is 585*65*50*195*7. Abrasive layer 1 is composed of CBN abrasive, phenolic resin powder, silicon carbide, chromium oxide, zinc oxide, hollow aluminum oxide balls, and glass microspheres. The CBN abrasive particle size is 100 / 120, the silicon carbide particle size is F400, the hollow aluminum oxide ball particle size is 1.5-2mm, and the glass microsphere particle size is 90-110μm. The total weight ratio of the grinding wheel formula is 100%, and the distribution ratio of its components is: 45% CBN abrasive, 25% phenolic resin powder, 20% silicon carbide, 3% chromium oxide, 3% zinc oxide, 2% hollow aluminum oxide balls, and 2% glass microspheres.

[0037] The preparation steps of the grinding wheel are the same as those in Example 1.

[0038] Comparative Example 1

[0039] The CBN particle size in Example 1 was replaced with 80 / 100, and the rest remained unchanged to obtain a double-end grinding wheel.

[0040] Comparative Example 2

[0041] The glass beads in the grinding wheel formula of Example 1 were removed, and the proportions of the components were: 30% CBN abrasive, 30% phenolic resin powder, 25% silicon carbide, 5% chromium oxide, 5% zinc oxide, and 5% hollow aluminum oxide balls. The rest was the same as Example 1, and a resin double-end grinding wheel was obtained.

[0042] Comparative Example 3

[0043] The hollow alumina balls in the grinding wheel formula of Example 1 were removed, and the proportions of the components were: 30% CBN abrasive, 30% phenolic resin powder, 25% silicon carbide, 5% chromium oxide, 5% zinc oxide, and 5% glass micro beads. The rest was the same as Example 1, and a resin double-end grinding wheel was obtained.

[0044] Comparative Example 4

[0045] The proportion of silicon carbide in the grinding wheel formula of Example 1 was adjusted, and the proportions of the components of the grinding wheel were: 30% CBN abrasive, 40% phenolic resin powder, 10% silicon carbide, 7% chromium oxide, 7% zinc oxide, 5% hollow aluminum oxide balls, and 1% glass microbeads. The rest remained unchanged to obtain a resin double-end grinding wheel.

[0046] The embodiment, comparative example and commercially available grinding wheels were used to grind gear materials. The gear material used was 20 chromium-molybdenum-titanium with a hardness of HBC58-63. The grinding results are shown in the following table:

[0047] grinding wheel Roughness / mm Flatness requirement / mm Surface quality after grinding Grinding stability Grinding sound Example 1 0.4 0.003 good good normal Example 2 0.42 0.003 good good normal Example 3 0.45 0.004 good good normal Comparative Example 1 0.6 0.006 good good normal Comparative Example 2 0.55 0.005 good generally normal Comparative Example 3 0.5 0.005 good generally normal Comparative Example 4 0.6 0.01 Scratches generally normal Commercially available grinding wheels 0.6 0.005 good good normal

[0048] The double-end CBN grinding wheel prepared by the present invention can effectively grind gear materials. The flatness of the workpiece after grinding can reach 0.003mm, the surface roughness of the workpiece after grinding is Ra0.4, the surface quality after grinding is good, and the grinding process is stable.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. 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 double-end grinding wheel for high-efficiency gear grinding, comprising a substrate and an abrasive layer arranged on the substrate, characterized in that: The abrasive layer comprises the following raw materials in weight percentage: 30-45% CBN abrasive, 25-30% phenolic resin powder, 20-25% silicon carbide, 2-5% chromium oxide, 2-5% zinc oxide, 2-5% hollow aluminum oxide ball and 1-2% glass microsphere.

2. The double-end grinding wheel for high-efficiency gear grinding according to claim 1, characterized in that: The particle size of CBN abrasive is 100 / 120-170 / 200, the particle size of silicon carbide is F400-F1200, the particle size of alumina hollow sphere is 1.5-2 mm, and the particle size of glass microbead is 90-110 μm.

3. A double-end grinding wheel for high-efficiency gear grinding according to claim 1 or 2, characterized in that: The abrasive layer is evenly provided with vertical grooves along the circumferential direction, and a single vertical groove is arranged along the radial direction. The abrasive layer is also provided with coaxial annular grooves, and the groove widths of the vertical grooves and the annular grooves are 2-3 mm.

4. The method for preparing a double-end grinding wheel for high-efficiency gear grinding according to any one of claims 1 to 3, characterized in that: The following steps are involved: (1) CBN abrasive, phenolic resin powder, silicon carbide, chromium oxide, zinc oxide and glass micro beads are weighed according to a ratio, and then put into a mixing barrel, and mixed by a three-dimensional mixer for 4 to 8 hours to make the powders uniformly mixed, and then hollow alumina balls are mixed and mixed uniformly to obtain a mixture; (2) After the mixed material is thrown on the substrate and scraped flat, it is pressed into an abrasive layer by a hot pressing method to obtain a prefabricated grinding wheel; (3) curing the prefabricated grinding wheel; (4) After curing, the grinding wheel is processed by a CNC lathe to the required grinding wheel size accuracy, and the grinding wheel surface edge is opened by a grinder to obtain a double-end CBN grinding wheel for gear grinding.

5. The preparation method according to claim 4, characterized in that: In step (2), the hot pressing method is as follows: the hot pressing temperature is 180° C., after the mixed material is scraped flat, the upper press is preheated for 3 to 5 minutes, vented 5 to 10 times, fixed molded, and pressed for 120 to 180 minutes.

6. The preparation method according to claim 4, characterized in that: In step (3), the curing process is: 40-60°C, curing for 1-2 hours; 70-90°C, curing for 2-4 hours; 100-120°C, curing for 2-4 hours; 130-150°C, curing for 2-4 hours; 160-190°C, curing for 8-12 hours.

7. The preparation method according to claim 4 or 6, characterized in that: In step (3), vertical grooves and annular grooves are firstly formed in the abrasive layer of the prefabricated grinding wheel, and then cured.

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