What if the temperature of full cylindrical roller bearing is too high?

If the temperature of the bearing used in mechanical equipment is too high, such as the abnormal condition of "fever", it is a common and harmful fault of mechanical equipment. If the cause is unknown and handled improperly, it will often get twice the result with half the effort. The service life of full loaded cylindrical roller bearing will increase the maintenance cost, and even lead to the burning out of the bearing. The selection of bearing matching types, It shall be determined according to the type and size of the bearing, the size and direction of the load and the nature of the load. The correct bearing fit shall ensure the normal operation of the bearing and prevent the relative rotation between the inner ring and the shaft, the outer ring and the housing hole during operation. Generally speaking, when the direction of the working load remains unchanged, the rotating ring has a tighter fit than the fixed ring, because the rotating ring bears the rotating load and the fixed ring bears the local load. When the rotating speed is higher, the load is greater and the vibration is stronger, the tighter fit shall be selected. When the bearing is installed on a thin-walled shell or hollow shaft, a tighter fit shall also be adopted.

However, too tight fit is disadvantageous. At this time, the internal clearance of the bearing may be reduced or even completely disappeared due to the elastic expansion of the inner outer ring and the contraction of the outer ring. It may also cause irregular deformation of the inner and outer rings of the bearing due to the irregular shape or uneven rigidity of the matched shaft and seat hole surface, which will destroy the normal operation of the bearing.

Too tight fit will also make assembly and disassembly difficult, especially for heavy machinery. With the introduction of adaptive control technology for modern high-precision grinding machines and high-precision lathes, the working parameters are automatically adjusted according to the changes of cutting conditions, so that the bearing can maintain a good working state in the machining process, so as to obtain higher machining accuracy and smaller surface roughness, At the same time, it can also improve the service life of the bearing and the noise of the bearing. It has the functions of self diagnosis and self repair. In the whole working state, the system can self diagnose and check the CNC system itself and various equipment connected to it at any time. In case of any fault, take measures such as shutdown immediately, and give a fault alarm to prompt 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 requirements of fault diagnosis, its development trend is to use artificial intelligence expert diagnosis system.

At present, CAD / CAM graphic interactive automatic programming has been widely used, which is a new trend of NC 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 difference of cam system programming is that the processing process parameters required for programming do not need to be manually involved, but are directly obtained from the CAPP database in the system. Speed and precision are two important indexes of high-precision NC grinder, It is directly related to processing efficiency and 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 adopted to improve the data processing ability of the system, that is, to improve the speed and accuracy of interpolation operation, so as to greatly reduce the internal and external ring error of the bearing, so as to improve the machining accuracy of the bearing.