SKF bearing preload types introduced

Depending on the type of bearing, the preload can be radial or axial. For example, cylindrical roller bearings can only withstand radial preload due to their design characteristics, while thrust ball bearings and cylindrical roller thrust bearings can only withstand axial preload. Single row angular contact ball bearings and tapered roller bearings are generally the same type with another bearing back to back or face-to-face configuration of the installation, this type of bearing plus axial preload. Deep groove ball bearings usually have to use axial preload, to do so, the radial internal clearance bearing should be larger than normal. For tapered roller bearings and angular contact ball bearings, when the bearings are arranged back to back, the distance L between their pressure centers is greater than the distance I between the centers of the bearings, and L is less than 1 in a face-to-face arrangement. This means that back-to-back bearings can withstand large overturning moments even with short bearing centers. The radial forces generated by moment loads in such bearings and the resultant deformation of the bearings are smaller than those of face-to-face bearings. If during operation the shaft temperature is higher than the chock, the preload adjusted (set) according to the ambient temperature during installation will increase, increasing in face-to-face increments greater than the back-to-back arrangement. When bearings are placed face to face, radial thermal expansion increases this tendency, while back to back reduces this tendency. With back-to-back arrangements, there is a certain distance between the bearings. When the bearing and the related components have the same thermal expansion coefficient, the radial and axial thermal expansions cancel each other out and the pre-load does not change.