First of all, attention should be paid to improving the quality of heat treatment, reducing the paralympic content and residual internal stress and the structural size changes caused by improper deformation, and avoiding the hardness exceeding HRC60, which will greatly reduce the grindability of carburized and quenched steel, especially avoid exceeding HRC62. Secondly, it is necessary to reduce the error of gear tooth pre-processing, reduce the tooth surface error of the prefabricated tooth, and avoid the improper transmission of the position error to the tooth surface error due to the improper pitch circle Zhao Zheng after the prefabricated tooth. In addition, the following measures have been found in the process layout to reduce the sensitivity of grinding burns and cracks to a certain extent. The gears that are shot peened before grinding have a positive effect due to the high-speed shot peening that can offset the residual internal stress; The workpiece with relatively long post-natural aging time has a positive effect due to the full release of its residual internal stress; the constant temperature treatment before grinding has a positive effect especially when the temperature is low in winter.
Improve gear alignment accuracy and increase the amount of tooth profile, tooth direction and tooth space before grinding, and increase the machining allowance appropriately to avoid grinding burns and cracks caused by overcutting during rough grinding During the grinding process, the current consumption of the grinding shaft and the change of the characteristic curve of the solid profile instrument should be monitored in time to find the grinding abnormality and readjust various parameters; maintain a sufficient amount of grinding oil, appropriately reduce the oil temperature and Constant temperature control, pay attention to timely adjustment of nozzle pressure and flushing position, as well as additional steps that can be added at the root of the grinding wheel HOFLER, and NILES can be modified to improve the conditions of grinding oil rushing in. These will affect the emission of grinding heat. Can play an improved role. When grinding burns and cracks are found, the burned tooth surface must be hand-finished with coarse sand skin and diamond files along the cracks to block the re-proliferation of the cracks. Secondly, the grinding wheel and the trimming parameters must be reselected. At the same time, it is necessary to reduce the amount of cutting tool, reduce the cutting speed and stroke speed appropriately, reduce the number of strokes and increase the number of cycles, reduce the number of intermediate dressing intervals of the grinding wheel, etc. for grinding treatment, pay attention to control the pure grinding current to not exceed 10A during grinding , When the cracks and burns are repaired until they are invisible to the eyes, the common normal line of the single tooth surface generally needs to be repaired at least about 0.03-0.1MM in order to really wear off the burns and cracks.

One: Editing principle of processing program
1. Under normal circumstances, the workpiece material with a larger modulus is more difficult to grind the workpiece with higher precision. Choose a smaller single step tool and a slower workpiece holder moving speed. The workpiece material with a smaller modulus is easy to grind and requires a lower accuracy. Choose a larger feed rate and a faster moving speed of the workpiece holder.
2. If there is a displacement in the editing program, the feed amount will be reduced in the stroke with displacement, the speed will be slowed down, and the feed amount of more than 0.1mm should be left after the displacement.
3. In the processing program, the total stroke number of the upper and retreat tool is selected as a single number, and the total stroke number of the lower tool retreat is selected as a double number. The key for controlling the direction of the tool retreat must be consistent with the direction in the program.
4. Generally, for workpieces with more than 40 teeth, the working speed of the grinding wheel is 1500r/min, and the height is 1650r/min. The working speed of the grinding wheel for workpieces below 40 teeth is appropriately reduced, and the low speed is 1000/min.
5. Sometimes in order to process high-precision workpieces, the rough and fine grinding can be separated, and two processing procedures can be changed. The rough grinding procedure reflects the efficiency and the fine grinding procedure ensures the accuracy.
Two: grinding wheel dressing
1. The single step knife amount of the grinding wheel is generally 0.03mm. When the modulus is large, the amount of cutter is appropriately reduced, and when the modulus is smaller, the amount of cutter is appropriately increased.
2. Sometimes in order to improve the processing efficiency, increase the feed amount during the one or two strokes after the dressing, to improve the sharpness of the grinding wheel grinding section, and sometimes in order to improve the processing accuracy, reduce the feed amount during the one or two strokes after the dressing , So that the grinding wheel can obtain a better shape
3. When the grinding wheel is repaired for the first time, it is necessary to run an empty stroke first to prevent collisions caused by the wrong setting of the modulus changing wheel or the wrong installation of the grinding wheel.
4. It is recommended that users use 80K grinding wheels for small modules and 80J grinding wheels for large modules.
5. The amount to be repaired after the grinding wheel is used up is determined by the modulus of the workpiece, the material of the workpiece and the grinding wheel, and the precision required for processing. The theoretical value is the modulus multiplied by 0.1 mm, and the small value of each trimming is 0.25 mm.
6. When correcting the tooth profile of the grinding wheel, the grinding wheel must not be turned after the gear is hung up.