Technical Paper
Fatigue Life of Diesel Engine Cams in Accelerated Test Environment
2003-03-03
2003-01-0052
Surface distress involving pitting, scuffing, frosting, and high friction leads to failure in fuel injector cams. The relationship amongst relative features of these failures is extremely complex. They comprise local plastic straining, cyclic softening/hardening, crack initiation/propagation, impact, skidding, and third body formation. From an industrial application point of view determination of failure probability and service life expectancy are important. Although factors such as operating loads, speeds, number of loading cycles, surface roughness, lubrication conditions, and third body particles are known to affect the life of gears and bearings, the effect of such factors on the life of cam-follower contact is little known. In particular, failure of cams due to pitting under conditions of rolling/sliding friction is unclear.