SKF cylindrical roller thrust bearings and components

81102 TN and 81136 M are complete bearings. The digits give series and size, and the letters at the end mark the execution. A designation that starts with K, like K 81104 TN, is the roller and cage assembly alone, with no washers.

Each washer has a prefix of its own. WS 81102 is the shaft washer and GS 81102 is the housing washer for the same size. They look alike but are not: one fits on the shaft with clearance in the housing, the other works the opposite way. Mix them up and the washer that should stay put ends up rubbing on the shaft or the housing.

When the machine's mating surfaces are hardened and ground, the roller assembly can run right on them, which saves even more space. That is the reason it is sold separately. Before ordering only the assembly, make sure the equipment was designed for it: on a soft surface the rollers leave marks within hours.

These bearings do not tolerate misalignment. The support faces must be parallel to each other and square to the shaft; if not, the rollers carry load at one end and wear shows up as an off-center ring. They also need a minimum axial load so the rollers roll instead of skidding, which matters on fast shafts with no thrust.

Send the full designation and tell us whether you need the complete bearing or one component. If there is no part number, measure the bore, the outside diameter and the overall height, and tell us which pieces were in the set you removed. Tell us which way the load acts, whether there is radial load at the same point and how it is lubricated. A photo of the washers helps us tell the shaft washer from the housing washer.