Radial roller bearing having hollow rollers
A radial roller bearing shafts in wind turbine transmissions, which includes an external bearing ring with an inner runway, an internal bearing ring arranged coaxial thereto which has an outer raceway and roller bodies on runways between bearing rings spaced circumferentially by a bearing cage and distributed uniformly on a circumference replaced by hollow rollers. To prevent slip, the hollow rollers have a greater diameter and lower modulus of elasticity ensuring, in a load-free state, continuous contact by the radial roller bearing with the bearing rings and continuous drive for the bearing cage and roller bodies at kinematic rotation speed. The hollow rollers have increased bending fatigue strength, and their inner envelope surfaces are formed by mechanical processing for further inherent compression stresses of at least −200 MPa, superimposed on the hollow rollers maximum load stress along with the inherent compression stresses resulting from their heat treatment.
1. A radial roller bearing for a bearing of shafts in wind power transmissions, comprising:
an outer bearing ring with an inner raceway;
an inner bearing ring, which is arranged coaxially with respect thereto and has an outer raceway;
a multiplicity of roller bodies which roll between the outer bearing ring and the inner bearing ring on the outer raceway and the inner raceway respectively and are held in a circumferential direction by a bearing cage; and
hollow rollers arranged between the roller bodies and held in the cage, the hollow rollers aid in preventing slip between the roller bodies and outer bearing ring and the inner bearing ring, and the hollow rollers have a slightly larger diameter and a lower modulus of elasticity than the roller bodies in order to ensure, in a load-free state of the radial roller bearing, a continuous contact with the outer bearing ring and the inner bearing ring and, thus, a continuous drive for the bearing cage and, thus, for the roller bodies at a kinematic rotation speed,
wherein the hollow rollers have have further inherent compression stresses of at least −200 MPa, which are superimposed on a maximum load stress of the hollow rollers in addition to the inherent compression stresses which result from a heat treatment of the hollow rollers.
2. The radial roller bearing as claimed in claim 1 , wherein the hollow rollers have a same axial length as the roller bodies and are formed with a total inherent compression stress of between −400 MPa and −800 MPa on their inner envelope surfaces.
3. The radial roller bearing as claimed in claim 2 , wherein the inner envelope surfaces of the hollow rollers are mechanically processed by compacting by hard rolling.
4. The radial roller bearing as claimed in claim 2 , wherein the inner envelope surfaces of the hollow rollers are mechanically processed by shot blasting.
5. The radial roller bearing as claimed in claim 2 , wherein the inner envelope surfaces of the hollow rollers are mechanically processed by calibration.