By optimising the raceway geometry and outer ring material on its range of X-life PWTR and PWKR yoke and stud type track rollers, Schaeffler has increased the basic rating life by up to 30 per cent and improved load carrying capacities by up to 50 per cent.
In addition, the optimised lateral surface profile and the improved surface quality of the outer ring mean there is reduced overall stress on the mating track. This provides a highly robust bearing support with an extended service life and higher efficiency.
Optimising the raceway geometry has increased the effective load carrying length of the rolling element; even at high loads, edge stresses are prevented. This leads to increased effective dynamic load ratings (by up to 9 per cent) and increased effective static load ratings (by up to 30 per cent). The basic rating life is therefore up to 30 per cent higher with the new range.
The outer ring material has been upgraded from case-hardened steel to through-hardened steel. Increased fatigue strength under reversed bending stress therefore leads to higher permitted dynamic ring load (by up to 50 per cent). Increased proof stress leads to higher permitted static ring load (by up to 30 per cent). The quality of the outside surface of the outer ring track is also improved by around 40 per cent, giving increased protection for the mating track.
X-life yoke and stud type track rollers are based on double-row cylindrical roller bearings and are fitted with lip seals to protect them against contamination. Separated by a central rib, the cylindrical rollers provide axial guidance of the outer ring. Stud type track rollers are equipped with a hexagonal socket on both sides of the roller stud. Customers can also request all-round corrosion protection in the form of Schaeffler's chromium-free Corrotect anti-corrosion coating, or with a special Triondur coating for increased anti-wear protection.