SKF KR52 PP Kurvenrollen (20x52x66)

As a track or cam roller, this component runs directly on a mating track or cam surface. At 20x52x66 mm and a unit weight of 0.512 kg, the installation envelope is fixed; further technical details are held in the specification table. The construction principle remains that of the stud-type track roller: an integrally formed threaded stud, a roller cantilevering out on one side, and a hardened outer ring rolling on the track.

The stud-type track roller differs from a roller guided between two cheeks by its fastening: it carries an integrally formed threaded stud, is screwed by it into a plate, a lever or a cheek, and cantilevers out from there on one side. Because the force from the contact with the track acts at the free end, a bending moment acts in the stud which is carried off through the seating face and the bolted joint; the seating, the tightening torque and the squareness of the mounting hole therefore belong in the layout, since a roller standing at an angle forces the contact pressure out to the edge of its running surface.

Versions with an eccentric stud allow the roller to be set against the track after mounting by turning it. The outer ring forms the running surface, is executed with a thick wall and hardened through the running depth under load; the mating track, with its hardness, surface finish and course, belongs to the layout and limits the load capacity of the pairing regardless of the size of the roller.

Rings and rolling elements are made of standard bearing steel. No separate catalogue attribute for the sealing of these items is available. That matters for the selection, because the sealing design determines two mutually opposing quantities at once: the protection against the debris that arises at every track, and the frictional torque, which can make a roller that is not driven but carried along by its track slide if it comes out too high. The information is to be taken from the type designation and the specification table of the individual item.