The development of Ferrography as a laboratory wear measurement method for the study of engine operating conditions on diesel engine wear

Abstract

Ferrographic oil analysis techniques were used in a laboratory study of diesel engine wear. Data were developed supporting the concept of using the Severity Index I s to rank the effect of engine operating conditions on wear. Results analyzing the Severity Index as a function of time and as a function of engine operating variables are presented. The Severity Index is also linearly correlated to spectrometric data (iron and lead concentrations in the used oil samples). Engine wear tends to increase with increase of either oil or coolant temperature. However, brake specific fuel consumption tends to decrease as oil and coolant temperatures increase, indicating a need for accurate temperature control for both mediums to minimize fuel consumption and wear. The heated Ferrogram analysis (HFA) technique was used to determine changes in the wear rates of specific engine parts with variation of the oil and coolant temperatures.