Question

For ball bearings, the fatigue life L measured in number of revolutions and the radial load F are related by FL^1/3 = K, where K is a constant. It withstands a radial load of 2 kN for a life of 540 million revolutions. The load (in kN) for a life of one million revolutions is

Answer 1

Concept:

For ball bearing,

FL^1/3 = K

F = Radial Load

L = Life in number of revolutions

Calculation:

Given:

F₁ = 2 kN, L₁ = 540 million revolutions, L₂ = 1 million revolutions

\({F_1}L_1^{\frac{1}{3}} = {F_2}L_2^{\frac{1}{3}}\)

2 × 540^1/3 = F₂(1)^1/3

∴ F₂ = 16.286 kN