The matching selection and installation accuracy requirements of cylindrical roller bearings and their important influence on operating stability

The matching selection and installation accuracy of cylindrical roller bearings are the basic conditions to ensure their operating stability, which has a decisive impact on bearing performance and life.Fit refers to the assembly relationship between the bearing, the shaft and the bearing seat hole, usually expressed by interference or clearance.The fit between the inner ring of cylindrical roller bearings and the shaft should be selected according to the nature, size and operating temperature of the load.Under the action of rotating load, the inner ring needs to adopt an interference fit with the shaft to prevent the inner ring from peristaltic wear on the shaft.The size of the interference amount needs to be appropriate. If it is too large, the inner ring will expand and crack or the clearance will be excessively reduced, and if it is too small, it may cause peristalsis.The fit between the outer ring and the bearing seat hole is determined according to the type of load. Interference fit is also required when bearing rotating loads, and transition or gap fit can be used when bearing stationary loads.

The installation accuracy requirements of cylindrical roller bearings involve many aspects and have an important impact on operating stability.The geometric accuracy of the mounting surface is the basis, and the roundness, cylinder and coaxiality of the journal and bearing seat holes should be controlled within the allowable range.The surface roughness is too large to reduce the effective contact area, which affects the reliability of the fit.During installation, special tools need to be used to apply force to the ferrule of the interference fit to avoid the transmission of installation force through the rolling element.For large cylindrical roller bearings, it may be necessary to install by temperature difference method. The inner ring is expanded by heating an oil bath or an induction heater to facilitate installation on the shaft.During the installation process, the bearing should be prevented from tilting, the axis of the inner and outer rings should be parallel, and the initial partial load should be avoided.

The installation accuracy of cylindrical roller bearings is also reflected in clearance control and axial positioning.The residual clearance after installation directly affects the bearing carrying performance and operating stability, and the appropriate range needs to be determined according to the working conditions.Axial positioning should ensure that the bearing can be freely retractable when the operating temperature changes, so as to avoid additional axial loads due to thermal expansion.For positioning bearings, they should be reliably fixed by lock nuts or end caps to prevent axial movement; for non-positioning bearings, sufficient axial movement should be left.Through precise control of fit, clearance and positioning, cylindrical roller bearings can be operated in the best condition, giving full play to their carrying capacity and speed potential, and ensuring the long-term stable operation of the equipment.