fluid analysis

by Walt Huysman, CLS, OMA

There are many tests available for used fluids analysis. Some tests are qualitative while others are quantitative in scope. One test often overlooked is Analytical Ferrography. Complete Analytical Ferrography is often referred to as the oil analysis equivalent of criminal forensic science. The test method relies on a visual, microscopic evaluation of particles, extracted and deposited on a microscope slide called a Ferrogram. Based on an examination of the shape, color, edge detail, the effects of a magnetic field and other diagnostic tests such as heat treatment and the addition of chemical reagents, an assessment of the active wear mechanism can be made.

by Ray Garvey
Emerson Process Management
Originally published in Lubrication & Fluid Power Magazine

ABSTRACT:

A brilliant new method called PPM distribution calculates precisely how much particulate debris is in the lubrication system. The systems debris values are calculated by multiplying the parts per million of debris by the lubricant volume to determine milliliters (ml or cc) of particulate debris in three adjacent size ranges: 4- to 6-microns, 6- to 14-microns, and >14-microns. Peaks in the distribution plot indicate the nominal size for each different source of contamination or wear. The proportional area under each peak reveals how much contamination or how much wear debris is in the lubrication system. This quantitative new method presents particle count information in an intuitive format. The result is easy interpretation of system contamination and realistic insight about the size of wearing defects. Examples are given showing how the PPM distribution can provide insights that might be missed by using the ISO 11171 code values for contamination control and wear indications.