Source:Sheng Wei networkAuthor:admin Addtime:2019/11/25 Click:
The bearing temperature used in mechanical equipment is too high, such as the abnormal condition of "fever", which is a common and harmful fault of mechanical equipment. If the cause is unknown and the treatment is improper, it will often do half the work with half the effort. The service life of the full cylindrical roller bearing will increase the maintenance cost, and even cause the burning of the bearing. The selection of bearing matching type should be based on the type and scale of the bearing The size and direction of the load and the nature of the load are determined. The correct selection of bearing fit shall ensure the normal operation of the bearing and prevent the relative rotation of inner ring and shaft, outer ring and shell hole during operation. Generally speaking, when the direction of the working load is constant, the rotating ring has a tighter fit than the fixed ring, because the rotating ring bears the rotating load, while the fixed ring bears the local load. When the higher the speed, the greater the load and the stronger the vibration, the tighter the fit should be selected. When the bearing is installed on a thin-walled shell or hollow shaft, a tight fit should also be used.Cylindrical roller bearing
But the over tight fit is unfavorable. At this time, the internal clearance of the bearing may be reduced or even completely disappeared due to the elastic expansion of the inner and outer rings and the contraction of the outer rings, or the irregular shape or uneven rigidity of the surface of the matched shaft and seat hole may lead to the irregular deformation of the inner and outer rings of the bearing, which will damage the normal operation of the bearing.
Too tight fit will also make it difficult to assemble and disassemble, especially for heavy machinery. With the introduction of adaptive control technology into modern high-precision grinding machines and high-precision lathes, working parameters can be automatically adjusted according to the change of cutting conditions, so that the bearing can maintain the best working state in the processing process, thus obtaining higher processing accuracy and smaller surface roughness, and at the same time, the bearing can be improved Service life and bearing noise. It has the function of self diagnosis and self repair. In the whole working state, the system can self diagnose and check the CNC system itself and its connected equipment at any time. In case of any fault, measures such as shutdown shall be taken immediately, and fault alarm shall be given to remind the location and cause of the fault. It can also automatically take the fault module offline and connect the standby module to ensure the requirements of unmanned working environment. In order to achieve higher fault diagnosis requirements, the development trend is to use artificial intelligence expert diagnosis system.
At present, CAD / CAM graphic interactive automatic programming has been widely used, which is the new trend of numerical control technology. It is a part processing drawing drawn by CAD, and then calculated and post processed by the tool path data in the computer. The biggest difference of cam system programming is that the processing process parameters required for its programming do not need to be participated in manually, and are obtained directly from the CAPP database in the system. Speed and precision are two important indexes of high-precision CNC grinder, which are directly related to the processing efficiency and production Product quality. At present, the numerical control system adopts the processor with higher number and frequency to improve the basic operation speed of the system. At the same time, the super large scale integrated circuit and multi microprocessor structure are used to improve the data processing ability of the system, that is, to improve the speed and accuracy of interpolation operation, to greatly reduce the error of the inner and outer rings of the bearing, so as to improve the processing accuracy of the bearing.