INA KR30 Kurvenrollen (12x30x40)

As a track or cam roller, this component runs directly on a mating track or cam surface. At 12x30x40 mm and a unit weight of 0.087 kg, the installation envelope is fixed; further technical details are held in the specification table. The integrally formed threaded stud remains the hallmark of the design: the roller is screwed in and cantilevers out on one side.

In this version a closely held annular gap between the outer ring and the end support bounds the rolling chamber. There is no element bearing against a surface, no friction point and nothing that recedes over the operating life; the effect rests solely on the narrowness of the gap and on the lubricant filling it. For a stud-type track roller this is a consistent configuration where starting behaviour is the priority: the roller is set turning by the track rather than driven, and a low breakaway torque has a share in deciding whether it rolls or slides on the track.

The limits are to be named just as clearly: a gap does not hold back moisture, fine dust or continuously arising debris; where these are present, a non-contact or a bearing seal is appropriate, and without a lubricant supply through the stud the relubrication interval has to be set correspondingly tighter. The fastening follows the design: the integrally formed threaded stud is screwed into a plate, lever or cheek, so that the roller cantilevers out on one side and the bending moment arising from the track force is carried off through the seating face and the bolted joint.

The squareness and flatness of the mounting determine whether the roller runs square to the track; an inclined position forces the contact pressure out to the edge of the running surface. The thick-walled outer ring, hardened through the running depth, takes the contact pressure from the track contact, and the hardness and course of the mating track have a share in determining the load capacity of the pairing. Rings and rolling elements are made of standard bearing steel.