Lubrication limits and equipment requirements for cylindrical roller bearings

Lubrication limitation: the starting torque of rolling bearings in grease lubrication applications usually increases significantly at lower temperatures. The starting torque is not mainly determined by the stability of the grease, but is usually determined by the rheological properties of the grease. The high temperature limit of grease is usually determined by the thermal stability, oxidation stability and antioxidant efficiency of base oil. Refer to the lubrication section on page 39 for details on lubrication restrictions.
Equipment requirements: equipment designers must evaluate the impact of temperature on equipment performance. For example, precision machine tool spindle bearings may be very sensitive to thermal expansion. For some spindles, special attention is required when the operating temperature is 20 ° C to 35 ° C higher than the ambient temperature. Most industrial equipment can work at quite high temperatures. For example, the drive gear can withstand a high temperature of 93 ° C. Gas turbine and other equipment can work continuously at temperatures above 100 ° C. However, when operating for a long time under high temperature conditions, the matching amount may be affected if the processing and heat treatment of the shaft and bearing seat are improper. Although the bearing can work normally at temperatures up to 120 ° C, the upper temperature limit of 80 ° C to 95 ° C is more realistic. Higher operating temperature will increase the instantaneous temperature peak, which increases the possibility of Timken bearing damage. Sample testing according to the specific application is helpful to determine the operating temperature range. The equipment designer should weigh all relevant factors and finally determine the required operating temperature.