When grinding wheels, the axis of the fast 9'' grinding wheel and the axis of the workpiece should be raised. The error of equal height can be judged according to the grinding pattern. The convex pattern on the surface of the grinded ball indicates that the second half of the grinding wheel takes part in grinding. At this time, the center position of the grinding wheel should be adjusted so that it is equal to the center of the workpiece until the surface of the grinded ball is cross-meshed.
The error of grinding wheel made in China when grinding external spherical surface is within 0.003-0.004mm. The grinding wheel rack must be rotated at a certain angle. The dressing of the inner hole size of the grinding wheel should be completed before the machine tool is adjusted. When the grinding wheel is blunt in the grinding process, there is no need to trim the inner hole, but only the end face of the grinding wheel can be trimmed with a grinding bar.
Because of the severe friction, the temperature of the grinding area is very high. This will cause stress and deformation of the workpiece and even burn the surface of the workpiece. Therefore, a large amount of coolant should be injected to reduce the grinding temperature. Coolant also acts as chip removal and lubrication.
The grinding force increases with the bluntness of the abrasive particles, resulting in the breakage or shedding of the abrasive particles and the re-exposure of the sharp edge. This characteristic is called self-sharpening. Self-sharpening makes grinding work normally within a certain period of time, but after a certain working time, it should be manually trimmed to avoid vibration, noise and damage to the surface quality of the workpiece caused by the increase of grinding force.
