Analysis on Cam Follower Contact Pressure of Fuel System

The increase of injection pressure leads to increase the contact stress of tappet roller body and raise more serious abrasion problem.The study analyzes the movement of cam roller body.The calculations of contact stress on different cam-roller are carried out with the FEM software.This study obtains the distribution regulation of cam-roller contact stress,and gets the influences on the regulation due to cam outline and roller outline.To verify fuel-injection system model,the pressure at delivery valve outlet is measured with high-pressure pump test-bed.The result finally finds the appropriate roller outline in order to reduce contact stress and increase using time.