FR/LR Series Track Roller bearings: FR series are for vee bars, LR series are for plain rollers.
The backlash setting and the pre-loading of the FR.., FR..R or LR.., LR..R series are performed by the eccentric hub.The FR..Z and LR..Z series are the concentric models.
In the eccentric rollers, the inner ring are provided with two blind holes, that allow the adjustment of the backlash. If a roller is located in its zero position, the rack and gear backlash will be the standard value of 0.05 mm.
The working life of the system will be reduced with excessive pre-loading. the rollers will not run if the lack of pre-loading, or will wear due to the poor meshing.
The guide roller have a very low coefficient of friction. This friction value is slightly increased by the fitting of wipers into the rails.
The roller is available in stainless steel with the suffix R.