A grinding process for the grinding wheel used in wind power gear grinding

Abstract

The present invention relates to the technical field of wind power gear processing, in particular to a grinding wheel grinding process for wind power gear grinding. A 3M 93DA80 grinding wheel is adopted, and the grinding process parameters include: (1) Grinding wheel dressing: 1) Speed ratio q; 2) The overlapping degree u ranges from 1.0 to 8.0; 3) Radial dressing depth a: When rough grinding the gear teeth, the radial dressing depth a is 0.05 mm; when fine grinding the gear teeth, the radial dressing depth a is 0.025 mm; (2) Grinding wheel grinding: 1) Grinding wheel linear speed v: When rough grinding, the linear speed v is 30 m / s; when fine grinding, the linear speed v is 35 m / s; 2) Stroke speed: When rough grinding, the stroke speed is relatively large, and when fine grinding, the stroke speed is relatively small; 3) Feed rate: Feed rate = Q'w × sinα × 60 / stroke speed; 4) Number of teeth N between two consecutive grinding wheel dressings: Number of teeth N between two consecutive grinding wheel dressings = (V'w × sinα × cosβ) / (2 × f × n × B).

Description

Technical Field

[0001] The present invention relates to the technical field of wind power gear processing, and specifically to a grinding wheel grinding process for wind power gear grinding. Background Art

[0002] With the continuous increase of the country's investment in the wind power generation industry, the demand for wind power generation equipment is also increasing. As a core component of wind power generation equipment, the performance of the wind power gearbox is one of the key factors affecting the efficiency and lifespan of wind power generation equipment. At the same time, because the maintenance cost of wind power generation equipment is very high, especially when replacing components, it is time-consuming and laborious; therefore, the wind power gearbox has extremely high requirements for lifespan and precision, especially the manufacturing quality of wind power gears is particularly crucial.

[0003] With the growth of the output of wind power gears, as the main transmission components in the wind power gearbox, the precision of wind power gears generally needs to reach ISO1328 grade 5 and the surface roughness Ra0.6. In the gear grinding process, the excellent selection of the grinding wheel will have a greater impact on the machining precision, surface quality, and machining efficiency of wind power gears.

[0004] At present, in the existing technology, the grinding wheel using Norton 3SG abrasive has a relatively low gear grinding efficiency, which will affect the delivery rate of products. Therefore, a more efficient grinding wheel is needed to replace it to meet the production needs. Summary of the Invention

[0005] The purpose of the present invention is to provide a grinding wheel grinding process for wind power gear grinding to solve the problems of low gear grinding efficiency, short grinding wheel lifespan, and high unit cost in the existing technology.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] A grinding wheel grinding process for wind power gear grinding uses a 3M 93DA80 grinding wheel, and the grinding process parameters include:

[0008] (1) Grinding wheel dressing

[0009] 1) Speed ratio q: When rough grinding gears, the grinding wheel dressing uses forward dressing, and the linear velocity direction of the diamond roller and the grinding wheel contact point is the same, and the speed ratio q takes a "+" value; when fine grinding gears, the grinding wheel dressing uses reverse dressing, and the linear velocity direction of the diamond roller and the grinding wheel contact point is opposite, and the speed ratio q takes a "-" value;

[0010] 2) Overlap ratio u: The value range of the overlap ratio u is 1.0 - 8.0; when rough grinding gears, the overlap ratio u of the grinding wheel dressing is smaller, and when fine grinding gears, the overlap ratio u of the grinding wheel dressing is larger;

[0011] 3) Radial dressing depth a: When rough grinding the teeth, the radial dressing depth a is taken as 0.05 mm; when finish grinding the teeth, the radial dressing depth a is taken as 0.025 mm;

[0012] (2) Grinding wheel grinding

[0013] 1) Grinding wheel linear speed v: When rough grinding, the linear speed v is taken as 30 m / s; when finish grinding, the linear speed v is taken as 35 m / s;

[0014] 2) Stroke speed: When rough grinding, the stroke speed is larger; when finish grinding, the stroke speed is smaller;

[0015] 3) Feed rate: Feed rate = Q'w × sinα × 60 / Stroke speed,

[0016] where, Q'w - Metal removal rate, α - Gear pressure angle, and the value range is 20° to 25°;

[0017] When rough grinding, Q'w ≤ 11; when semi-finish grinding, Q'w ≤ 7; when finish grinding, Q'w ≤ 3;

[0018] 4) Number of teeth N for grinding wheel dressing interval: Number of teeth N for grinding wheel dressing interval = (V'w × sinα × cosβ) / (2 × f × n × B);

[0019] where, V'w - Metal removal amount, α - Gear pressure angle, β - Gear helix angle, f - Normal feed rate, n - Stroke number, B - Gear width;

[0020] where, when rough grinding, V'w ≤ 2500; when semi-finish grinding, V'w ≤ 900; when finish grinding, V'w ≤ 300;

[0021] When rough grinding, f = 0.05 - 0.06; when semi-finish grinding, f = 0.017 - 0.03; when finish grinding, f = 0.006 - 0.011;

[0022] When rough grinding, n = 1; when semi-finish grinding, n = 2 - 4; when finish grinding, n = 1;

[0023] The value range of the number of teeth N for dressing interval is 3 to 6, and the specific value is obtained according to the calculation.

[0024] where, the speed ratio q is the ratio of the linear speed Vr of the diamond roller surface to the linear speed Vc of the grinding wheel surface, q = Vr / Vc.

[0025] where, the overlap ratio u = b / s, where, b represents the effective working width of the diamond roller, and s represents the feed rate during diamond roller dressing.

[0026] where, the grinding wheel linear speed is the rotational speed during grinding wheel machining.

[0027] Among them, the stroke speed is the speed at which the grinding wheel moves along the width direction of the workpiece teeth during gear grinding.

[0028] Among them, the feed rate is the feed depth of the grinding wheel along the normal direction of the tooth surface during gear grinding.

[0029] Among them, during gear grinding, after dressing the grinding wheel, the grinding wheel needs to be dressed again after grinding a certain number of teeth. The certain number of teeth ground is called the dressing interval teeth of the grinding wheel.

[0030] Compared with the prior art, the beneficial effects of the present invention are:

[0031] The grinding wheel grinding process for wind power gear grinding of the present invention uses a 3M 93DA80 grinding wheel, and through a large number of experiments, the optimal grinding wheel grinding process parameters are obtained. As a high-performance grinding wheel for grinding processing, in the microscopic structure of the 3M 93DA80 grinding wheel, each abrasive is a standard-sized triangle. In the grinding process, this triangular-structured abrasive has extremely strong stock removal ability. Through the cooperation of a series of grinding wheel grinding processes, the processing efficiency of gear grinding will be greatly improved. Through comparative experiments, it is verified that the grinding wheel processing efficiency of the grinding wheel grinding process of the present invention has been greatly improved, effectively reducing the production and processing costs. The grinding wheel grinding process of the present invention can be popularized and applied to the gear grinding of wind power gears. Description of the Drawings

[0032] Figure 1 It is the microscopic structure of the 3M 93DA80 grinding wheel; among them, 1 - large pores, 2 - triangular abrasives.

[0033] Figure 2 It is the microscopic structure of the Norton 3SG grinding wheel; among them, 3 - irregular abrasives, 4 - pores.

[0034] Figure 3 It is a schematic diagram of the grinding process of the 3M 93DA80 grinding wheel; among them, 2 - triangular abrasives, 5 - continuous chips.

[0035] Figure 4 It is a schematic diagram of the grinding process of the Norton 3SG grinding wheel; among them, 3 - irregular abrasives, 6 - discontinuous chips.

[0036] Figure 5 It is a schematic diagram of the process of dressing the grinding wheel with a diamond roll.

[0037] Figure 6 It is the influence of the speed ratio on the tooth surface roughness.

[0038] Figure 7 It is the influence of the overlap ratio on the tooth surface roughness.

[0039] Figure 8It is the grinding current value of the 3M 93DA80 grinding wheel.

[0040] Figures 9 - 10 It is the gear precision inspection result.

[0041] Figure 11 It is the tooth surface roughness inspection result.

[0042] Figure 12 It is the comparison of gear grinding efficiency, grinding wheel life and unit cost between the 3M 93DA80 grinding wheel and the Norton 3SG grinding wheel. Specific implementation mode

[0043] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0044] A grinding wheel grinding process for wind power gear grinding uses a 3M 93DA80 grinding wheel, and the grinding process parameters include:

[0045] (1) Grinding wheel dressing

[0046] 1) Speed ratio q: When rough grinding teeth, the grinding wheel dressing adopts forward dressing, and the linear velocity direction of the diamond roller and the grinding wheel contact point is the same, and the speed ratio q takes a "+" value; when fine grinding teeth, the grinding wheel dressing adopts reverse dressing, and the linear velocity direction of the diamond roller and the grinding wheel contact point is opposite, and the speed ratio q takes a "-" value;

[0047] 2) Overlap ratio u: The value range of the overlap ratio u is 1.0 - 8.0; when rough grinding teeth, the overlap ratio u of the grinding wheel dressing is smaller, and when fine grinding teeth, the overlap ratio u of the grinding wheel dressing is larger;

[0048] 3) Radial dressing depth a: When rough grinding teeth, the radial dressing depth a takes 0.05 mm; when fine grinding teeth, the radial dressing depth a takes 0.025 mm;

[0049] (2) Grinding wheel grinding

[0050] 1) Grinding wheel linear velocity v: When rough grinding, the linear velocity v takes 30 m / s; when fine grinding, the linear velocity v takes 35 m / s;

[0051] 2) Stroke speed: When rough grinding, the stroke speed is larger, and when fine grinding, the stroke speed is smaller;

[0052] 3) Feed rate: Feed rate = Q'w × sinα × 60 / stroke speed,

[0053] Among them, Q'w is the metal removal rate, α is the gear pressure angle, and the value range is 20° to 25°;

[0054] During rough grinding, Q'w ≤ 11; during semi-finish grinding, Q'w ≤ 7; during finish grinding, Q'w ≤ 3;

[0055] 4) The number of teeth N for wheel dressing interval: The number of teeth N for wheel dressing interval = (V'w × sinα × cosβ) / (2 × f × n × B);

[0056] Among them, V'w is the metal removal amount, α is the gear pressure angle, β is the gear helix angle, f is the normal feed rate, n is the number of strokes, and B is the gear width;

[0057] Among them, during rough grinding, V'w ≤ 2500; during semi-finish grinding, V'w ≤ 900; during finish grinding, V'w ≤ 300;

[0058] During rough grinding, f = 0.05 - 0.06; during semi-finish grinding, f = 0.017 - 0.03; during finish grinding, f = 0.006 - 0.011;

[0059] During rough grinding, n = 1; during semi-finish grinding, n = 2 - 4; during finish grinding, n = 1;

[0060] The value range of the number of teeth N for dressing interval is 3 - 6, and the specific value is obtained according to the calculation.

[0061] 1. Microstructure comparison between the 3M 93DA80 grinding wheel adopted by the present invention and the traditional Norton 3SG grinding wheel

[0062] The grinding wheel is a porous body composed of abrasive and binder, and the microstructure of the grinding wheel is composed of abrasive, binder and pores. Figure 1 The microstructure of the 3M 93DA80 grinding wheel: It is composed of triangular abrasives 2 of standard size and large pores 1; Figure 2 The microstructure of the Norton 3SG grinding wheel: It is composed of irregular abrasives 3 with irregular shapes and pores 4.

[0063] Compared with the irregularly shaped abrasives of the Norton 3SG grinding wheel, the triangular abrasives of the 3M 93DA80 grinding wheel have sharp cutting edges and can quickly remove a large amount of surplus. The grinding wheel with such triangular-structured abrasives can greatly improve the processing efficiency; compared with the pores of the Norton 3SG grinding wheel, the 3M 93DA80 grinding wheel has larger pores. The large-pore structure of the grinding wheel can more effectively bring the cooling oil to the grinding area during the grinding process, facilitating cooling and effectively reducing the risk of tooth surface burn.

[0064] 2. Chip comparison in grinding machining

[0065] The grinding process of the grinding wheel is similar to the turning process of a lathe. Each abrasive on the grinding wheel is actually equivalent to a cutting tool, and the grinding process is actually a machining process of multi-tool simultaneous cutting.

[0066] Figure 3 It is a microscopic magnification of the grinding process of the abrasive of the 3M 93DA80 grinding wheel. Its abrasive is in a regular triangular shape. The abrasive in the shape of a triangle has a sharp cutting edge. The cut chips are in a continuous long strip filament shape, with almost no extrusion deformation of the material. Less cutting heat is generated during the grinding process, which is beneficial to reducing the risk of grinding burns; the long strip filament-shaped chips will not block the pores of the grinding wheel, enabling the grinding wheel to maintain a sharp state better.

[0067] Figure 4 It is a microscopic magnification of the grinding process of the abrasive of the Norton 3SG grinding wheel. Its abrasive is in an irregular shape. During the grinding process, since the abrasive does not have a sharp cutting edge, the cutting process of the abrasive is actually a process of continuous extrusion deformation of the material. A large amount of cutting heat will be generated during the grinding process, which will increase the risk of grinding burns; the cut chips are in a discontinuous granular shape, and this discontinuous-shaped chips are easy to block the pores of the grinding wheel, making the grinding wheel easy to become dull and not conducive to continuous grinding processing.

[0068] 3. Selection of Grinding Process Parameters for the 3M 93DA80 Grinding Wheel

[0069] During the profile grinding process of gears, to ensure the machining accuracy and efficiency of parts, in addition to the high motion accuracy of the gear grinding machine itself, it is also related to the dressing parameters of the grinding wheel and the selection of grinding parameters of the grinding wheel.

[0070] 1) Selection of Dressing Parameters of the Grinding Wheel

[0071] During the gear profile grinding process, due to the action of grinding force and high temperature in the grinding contact area, the abrasives on the surface of the grinding wheel will gradually become dull. In order to keep the grinding wheel in a good grinding state, after grinding for a certain time, the grinding wheel must be dressed to maintain the good surface quality and high-precision geometric profile of the grinding wheel. The grinding performance of the grinding wheel and the final machining quality of the gears largely depend on the surface condition of the grinding wheel, which has a great relationship with the dressing accuracy of the grinding wheel and the setting of dressing parameters of the grinding wheel; the dressing process of the grinding wheel mainly includes three parameters: speed ratio q, overlap ratio u, and radial dressing depth a.

[0072] A. Selection of Speed Ratio q

[0073] The speed ratio q refers to the ratio of the linear speed Vr of the surface of the diamond roll to the linear speed Vc of the surface of the grinding wheel when dressing the grinding wheel.

[0074] Speed ratio q = Vr / Vc

[0075] When the linear velocity directions at the contact points between the diamond roller and the grinding wheel are the same, it is forward dressing, and q takes the value of "+", otherwise it is reverse dressing and q takes the value of "-".

[0076] When the dressing speed ratio q takes the value of "+", the relative speed between the diamond roller and the grinding wheel is small, and the interaction force is mainly the extrusion force. After the grinding grains of the grinding wheel are extruded, more grinding grains of the grinding wheel break, and the formed cutting edges are sharper, but the overall profile accuracy of the grinding wheel is slightly worse, which is suitable for rough grinding to remove a large amount of grinding allowance.

[0077] When the dressing speed ratio q takes the value of "-", the relative speed between the diamond roller and the grinding wheel is high. When dressing the grinding wheel, more micro-edges will be formed, and the overall profile accuracy of the grinding wheel is high, which is suitable for precision grinding.

[0078] Therefore, when dressing the grinding wheel for rough grinding of teeth, forward dressing is generally adopted, and q takes the value of "+", while when dressing the grinding wheel for precision grinding of teeth, reverse dressing is adopted, and q takes the value of "-". Figure 6 It is the influence degree and change trend of the speed ratio q on the tooth surface roughness.

[0079] B. Selection of overlap ratio u

[0080] The overlap ratio u = b / s;

[0081] In the formula: b represents the effective working width of the diamond roller;

[0082] S represents the feed rate during the dressing of the diamond roller.

[0083] During the process of the diamond roller dressing the grinding wheel (such as Figure 5 ), assuming that the effective working width b of the diamond roller is a fixed value, when the feed rate during the dressing of the diamond roller is larger, the overlap ratio u is smaller. At this time, the surface of the grinding wheel is dressed more coarsely, and the tooth surface roughness during gear grinding is larger, which is suitable for rough grinding; when the feed rate during the dressing of the diamond roller is smaller, the overlap ratio u is larger. At this time, the surface of the grinding wheel is dressed more finely, with high profile accuracy, and the tooth surface roughness during gear grinding is smaller, which is suitable for precision grinding.

[0084] Generally, the overlap ratio u for dressing the grinding wheel is selected between 1.0 and 8.0. When dressing the grinding wheel for rough grinding of teeth, the overlap ratio u takes a smaller value, and when dressing the grinding wheel for precision grinding of teeth, the overlap ratio u takes a larger value. Figure 7 It is the influence degree and change trend of the overlap ratio u on the tooth surface roughness.

[0085] C. Selection of radial dressing depth a

[0086] When dressing the grinding wheel, the radial dressing depth a (see Figure 5)It affects the force characteristics of the grinding wheel grains. When the dressing depth a is relatively large, the grains are fractured and broken under force, and part of the bond falls off, forming sharp cutting edges and chip spaces, which is suitable for rough grinding. When the dressing depth a is relatively small, the damage strength of the grinding wheel grains is relatively small, resulting in microscopic fractures and forming micro-edges with high profile accuracy, which is suitable for finish grinding.

[0087] The selection of the radial dressing depth a should consider the grain size of the grinding wheel to avoid excessive dressing amount that causes the entire abrasive to fall off, which not only wastes the abrasive but also makes it difficult to form the profile. Generally, when rough grinding, the radial dressing depth a is taken as 0.05 mm, and when finish grinding, the radial dressing depth a is taken as 0.025 mm.

[0088] 2) Selection of grinding wheel grinding parameters

[0089] During the gear form grinding process, the setting of grinding parameters affects the machining efficiency and quality of parts. The main grinding parameters during gear grinding with a grinding wheel include: grinding wheel linear speed, stroke speed, feed rate, metal removal rate, number of teeth for grinding wheel dressing interval, etc.

[0090] A. Selection of the grinding wheel linear speed v

[0091] The grinding wheel linear speed refers to the rotational speed during the grinding wheel grinding process. Generally, when rough grinding, the linear speed v is taken as about 30 m / s, and when finish grinding, the linear speed v is taken as about 35 m / s.

[0092] B. Selection of the stroke speed

[0093] The stroke speed refers to the speed at which the grinding wheel moves along the tooth width direction of the workpiece during gear grinding, with the unit of mm / min. The setting and selection of the stroke speed affect the machining efficiency and quality of parts. Generally, the stroke speed is larger during rough grinding and smaller during finish grinding.

[0094] C. Selection of the feed rate

[0095] The feed rate refers to the feed depth along the normal direction of the tooth surface during gear grinding with a grinding wheel and can be set by calculation using a formula;

[0096] Feed rate = Q'w × sinα × 60 / stroke speed

[0097] In the formula: Q'w - metal removal rate (generally, Q'w ≤ 11 for rough grinding, Q'w ≤ 7 for semi-finish grinding, Q'w ≤ 3 for finish grinding), α - gear pressure angle.

[0098] D. Selection of the number of teeth N for grinding wheel dressing interval

[0099] The number of teeth N for grinding wheel dressing interval refers to the number of teeth (removing a certain amount of metal) that the grinding wheel needs to grind after dressing the grinding wheel during gear grinding before it needs to be dressed again. The certain number of teeth ground is called the number of teeth for grinding wheel dressing interval.

[0100] The number of teeth N for dressing interval of the grinding wheel = (V'w × sinα × cosβ) / (2 × f × n × B)

[0101] Where: V'w — Metal removal rate;

[0102] α — Gear pressure angle;

[0103] β — Gear helix angle;

[0104] f — Normal feed rate;

[0105] n — Number of strokes;

[0106] B — Gear width.

[0107] 4. Verification of Grinding Process Parameters for 3M 93DA80 Grinding Wheel

[0108] The 3M 93DA80 grinding wheel is popularized and applied to the gear grinding of wind power gear parts to improve the gear grinding efficiency. It is necessary to conduct process verification on the grinding process of the 3M 93DA80 grinding wheel to verify that the gear grinding quality of the 3M 93DA80 grinding wheel meets the requirements of the drawing.

[0109] (1) Process of Verifying Grinding Process of 3M 93DA80 Grinding Wheel

[0110] Table 1 Basic Parameters of the Verified Parts

[0111] Table 1 shows the basic parameters of the verified parts, the grinding wheel model and the specifications of the diamond roll. The verification of the grinding process of the 3M 93DA80 grinding wheel is carried out on the ZP20 CNC profile grinding machine;

[0112] Align the workpiece according to the requirements of the gear grinding operation instruction book and input the gear parameters; input the grinding parameters and the dressing parameters of the grinding wheel according to the parameters in Table 2. After dressing the grinding wheel, carry out gear grinding (stock removal) processing on the parts.

[0113] Table 2 Grinding Parameters and Dressing Parameters of 3M 93DA80 Grinding Wheel

[0114]

[0115]

[0116] Since the stroke speed, feed rate and metal removal rate during the grinding process of the 3M 93DA80 grinding wheel are significantly higher than those of the Norton 3SG grinding wheel, the grinding current is monitored in real time during the processing, Figure 8 is the grinding current value of the 3M 93DA80 grinding wheel.

[0117] (2) Results of Verifying Grinding Process of 3M 93DA80 Grinding Wheel

[0118] After gear grinding is completed, check the gear accuracy as required: If it meets the requirements, see Figures 9 - 10 .

[0119] Magnetic particle flaw detection inspection: There are no grinding cracks on the tooth surface; Burn inspection: There is no burn on the tooth surface.

[0120] Tooth surface roughness detection: Ra0.275 for the left tooth surface and Ra0.288 for the right tooth surface, see Figure 11 .

[0121] 5. Comparison of the usage effects of 3M 93DA80 grinding wheel and Norton 3SG grinding wheel

[0122] Through the verification of the grinding process of the 3M 93DA80 grinding wheel, it is verified that the grinding quality meets the requirements of the drawing, the processing efficiency has been greatly improved, and it has great advantages compared with the Norton 3SG grinding wheel. The comparison is mainly carried out from the grinding processing efficiency, the service life of the grinding wheel and the single-piece production cost, as Figure 12 shown.

[0123] Table 3 is the statistics of the grinding time, the number of grinding wheel dressing times, and the grinding wheel dressing amount of the 3M 93DA80 grinding wheel and the Norton 3SG grinding wheel for machining the same kind of planetary gear.

[0124] Table 3

[0125] 3M 93DA80 Grinding Wheel Norton 3SG Grinding Wheel Total Grinding Stock 1.96 mm 1.94 mm Grinding Time 2 hours and 45 minutes 5 hours and 26 minutes Number of Wheel Dressings 31 times 75 times Wheel Dressing Amount 1.62 mm 3.25 mm

[0126] (1) Comparison of grinding processing efficiency

[0127] It can be seen from Table 3 that under the same grinding allowance, the grinding time for machining one planetary gear with the 3M 93DA80 grinding wheel is 2 hours and 45 minutes; the grinding time for machining one planetary gear with the Norton 3SG grinding wheel is 5 hours and 26 minutes. The grinding time of the 3M 93DA80 grinding wheel saves 2 hours and 41 minutes per piece compared with the Norton 3SG grinding wheel. The grinding time of the 3M 93DA80 grinding wheel for machining one workpiece is 50.61% of that of the Norton 3SG grinding wheel, and the processing efficiency of the 3M new grinding wheel has increased by 49.39%.

[0128] (2) Comparison of the service life of the grinding wheel

[0129] It can be seen from Table 3 that under the same grinding allowance, the number of grinding wheel dressing times for machining one planetary gear with the 3M 93DA80 grinding wheel is 31 times and the grinding wheel dressing amount is 1.62 mm; the number of grinding wheel dressing times for machining one planetary gear with the Norton 3SG grinding wheel is 75 times and the grinding wheel dressing amount is 3.25 mm.

[0130] The dressing amount (consumption) of the grinding wheel: The 3M 93DA80 grinding wheel reduces by 1.63 mm per piece compared with the Norton 3SG grinding wheel, and the grinding wheel consumption rate of the 3M 93DA80 grinding wheel reduces by 50.1% compared with the Norton 3SG grinding wheel; The service life of the 3M 93DA80 grinding wheel is twice that of the Norton 3SG grinding wheel.

[0131] (3) Comparison of the production cost per piece

[0132] Table 4

[0133]

[0134] The production cost per piece = B / A + C * 267, and the hourly price of the ZP20 gear grinding machine is 267 yuan.

[0135] Through the verification of the grinding process of the 3M 93DA80 grinding wheel, it is verified that the grinding quality meets the design requirements. By comparing the grinding efficiency, the service life of the grinding wheel and the production cost per piece of the 3M 93DA80 grinding wheel and the Norton 3SG grinding wheel, it is verified that the grinding efficiency of the grinding wheel of the present invention has been greatly improved, and the production and processing cost has been effectively reduced; The grinding process of the grinding wheel of the present invention can be widely applied to the grinding of wind power gears.

[0136] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A grinding process for the grinding wheel used in wind power gear grinding, characterized in that: 3M 93DA80 grinding wheel is adopted, and the grinding process parameters include: (1) Grinding wheel dressing 1) Speed ratio q: When rough grinding the gear teeth, the grinding wheel dressing adopts forward dressing, and the linear velocity directions of the diamond roller and the grinding wheel contact point are the same, and the speed ratio q takes the "+" value; when fine grinding the gear teeth, the grinding wheel dressing adopts reverse dressing, and the linear velocity directions of the diamond roller and the grinding wheel contact point are opposite, and the speed ratio q takes the "-" value; 2) Overlap ratio u: The value range of the overlap ratio u is 1.0 - 8.0; when rough grinding the gear teeth, the overlap ratio u of the grinding wheel dressing is smaller, and when fine grinding the gear teeth, the overlap ratio u of the grinding wheel dressing is larger; 3) Radial dressing depth a: When rough grinding the gear teeth, the radial dressing depth a takes 0.05 mm; when fine grinding the gear teeth, the radial dressing depth a takes 0.025 mm; (2) Grinding wheel grinding 1) Grinding wheel linear velocity v: When rough grinding, the linear velocity v takes 30 m / s; when fine grinding, the linear velocity v takes 35 m / s; 2) Stroke speed: When rough grinding, the stroke speed is larger, and when fine grinding, the stroke speed is smaller; 3) Feed rate: Feed rate = Q'w × sinα × 60 / stroke speed, where, Q'w - metal removal rate, α - gear pressure angle, and the value range is 20° - 25°; When rough grinding, Q'w ≤ 11; when semi - fine grinding, Q'w ≤ 7; when fine grinding, Q'w ≤ 3; 4) Number of teeth N between grinding wheel dressings: Number of teeth N between grinding wheel dressings = (V'w × sinα × cosβ) / (2 × f × n × B); where, V'w - metal removal amount, α - gear pressure angle, β - gear helix angle, f - normal feed rate, n - number of strokes, B - gear width; where, when rough grinding, V'w ≤ 2500; when semi - fine grinding, V'w ≤ 900; when fine grinding, V'w ≤ 300; When rough grinding, f = 0.05 - 0.06; when semi - fine grinding, f = 0.017 - 0.03; when fine grinding, f = 0.006 - 0.011; When rough grinding, n = 1; when semi - fine grinding, n = 2 - 4; when fine grinding, n = 1; The value range of the number of teeth N between dressings is 3 - 6, and the specific value is obtained according to the calculation.

2. The grinding process for the grinding wheel used in wind power gear grinding according to claim 1, characterized in that: The speed ratio q is the ratio of the linear velocity Vr of the diamond roller surface to the linear velocity Vc of the grinding wheel surface, q = Vr / Vc.

3. The grinding process for the grinding wheel used in wind power gear grinding according to claim 2, characterized in that: The overlap ratio u = b / s, where, b represents the effective working width of the diamond roller, and s represents the feed rate when the diamond roller is dressing.

4. The grinding process for the grinding wheel used in wind power gear grinding according to claim 3, characterized in that: The grinding wheel linear velocity is the rotational speed during the grinding wheel grinding process.

5. The grinding process for the grinding wheel used in wind power gear grinding according to claim 4, characterized in that: The stroke speed is the speed at which the grinding wheel moves along the width direction of the workpiece tooth during the gear grinding process.

6. The grinding process for the grinding wheel used in wind power gear grinding according to claim 5, characterized in that: The feed rate is the feed depth of the grinding wheel along the normal direction of the tooth surface during gear grinding.

7. The grinding wheel grinding process for wind power gear grinding according to claim 6, characterized in that: During gear grinding with the grinding wheel, after dressing the grinding wheel, it is necessary to dress the grinding wheel again after grinding a certain number of teeth. The certain number of teeth ground is called the dressing interval teeth of the grinding wheel.

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