Forklift Wheel Bearing Life Calculator

L10 is the life that 90% of identical bearings reach under the same load and speed before the first sign of fatigue — equivalently, a 10% failure probability. Median life is roughly 5× L10. It is a statistical fatigue life, not a guarantee for any single bearing.

Neither alone — use a duty-weighted equivalent. ISO 281 practice combines load cases with P_eq = (Σ(tᵢ·Pᵢ³·nᵢ)/Σ(tᵢ·nᵢ))^(1/3) for ball, exponent 10/3 for rollers. A quick approximation: if 60% of travel is laden at P₁ and 40% empty at P₂, the cubic mean sits much closer to P₁ — load dominates. Enter that equivalent here.

C (basic dynamic load rating) is printed in every bearing datasheet — for example a 30207 taper roller (C ≈ 76.5 kN) in a 2.5 t forklift drive wheel at low speed. P is the equivalent dynamic load: for pure radial load it is simply the radial force; with combined radial + axial load use P = X·Fr + Y·Fa with X and Y from the datasheet.

Because L10 assumes clean lubricant, correct fit and alignment. In practice most bearings die of lubrication failure, contamination, misalignment or fitting damage rather than fatigue. If yours fail early, check the actual load path and the grease before blaming the bearing.

Use p = 3 for ball bearings and p = 10/3 for roller bearings (cylindrical, spherical, taper). Rollers carry load on a line contact rather than a point, so their life is less sensitive to load — that is what the higher exponent encodes.