NSK 2206 K-2RSTNGC3 Pendelkugellager (30x62x20)

As a self-aligning ball bearing, this bearing compensates for misalignment and shaft deflection. This NSK bearing measures 30x62x20 mm and weighs 0.261 kg; the specification table carries the supplementary technical details. This variant features a contact seal and increased radial clearance (C3). The bearing seal lip introduces friction heat of its own — and heat consumes radial play, which increased clearance (C3) provides here from the outset.

In this version the sealing and the clearance class engage with one another through the heat balance of the bearing position. The contact seal on both sides keeps the grease charge with the rows of balls and contamination away from the raceways; in return its lip rubs on the counterface and releases heat in addition to the rolling friction.

That heat stands in the same calculation as a tight inner ring seat, a drive-up distance on an adapter sleeve or a warm adjacent construction — it expands the inner ring more than the outer ring and reduces the mounted radial play. Increased clearance (C3) sets the initial play correspondingly higher, so that in warm service a residual play remains within the intended range and the ball set is not braced.

For the layout, three quantities therefore have to be considered together: the type of seat with its expansion of the inner ring, the temperature gradient between the rings, and the speed, which together with the frictional torque of the seal determines the operating temperature. The permissible speed of this version is tied to the seal, as are the limits for operating temperature and media resistance.

The alignment capability is retained, but the permissible misalignment comes out smaller than in the open version because of the seal carried along. Rings and balls are made of through-hardened standard bearing steel, and the load rating stays tied to the low conformity of the spherical outer raceway.