SKF YAT208 Spannlager (40x80x36)

As an insert (Y) bearing, this bearing is located on the shaft and used in a housing. The dynamic load rating of 30.7 kN characterises this bearing. The static load rating is 19 kN. This variant features a contact seal. The widened inner ring accommodates the shaft locking and turns a ball bearing into a component that grips the shaft itself.

The insert bearing is a ball bearing built for one particular mounting situation: the drawn, unstepped shaft with no machined bearing seat. Two features therefore distinguish it from an ordinary deep groove ball bearing. The inner ring is widened beyond the outer ring and accommodates the shaft locking — depending on the version, grub screws, an eccentric locking collar or an adapter sleeve — so that the bearing grips the shaft itself instead of being held by an interference fit.

And the outer surface is not cylindrical but spherical; it sits in the spherical seat of a plummer block, flanged or take-up housing and allows the bearing position to align itself to the shaft during mounting. Its limits follow from this construction just as much as its advantages: because the locking works on a shaft with wider tolerances than a machined bearing seat, running accuracy and permissible speed are lower than for a bearing fitted into a machined seat, and the alignment movement serves to set the unit up during mounting, not for continuous operation under changing misalignment.

The contact seal on both sides closes the rolling chamber and keeps the grease charge introduced at the works with the balls — the reason this design is found at bearing positions that are seldom or never maintained; where a grease nipple is present, the relubrication interval nonetheless belongs in the maintenance plan. Rings and balls are made of standard bearing steel.

A clearance class is not recorded as a separate catalogue attribute for these items and is to be taken from the specification table. The design is loadable primarily in the radial direction.