Dynamic Particle Generation/Shedding in Lubricating Greases Used in Aerospace Applications
Abstract:
The purpose of this study is to examine the phenomenon of Dynamic Particle
Generation in lubricating greases that are used in a variety of critical
Aerospace mechanisms. Particle Generation occurs in bearings, ball screws, and
other mechanical devices where dynamic conditions are present. This should not
be confused with outgassing as particle generation is unrelated to the pressure
effects on a system. This is a critical factor in many systems as particle
generation can contaminate systems or processes causing them to fail. These
failures can lead to excessive costs, production failure, and equipment
damage.
In this study, several greases made from Multiplyalkylated Cyclopentane and
Perfluoropolyether base fluids were tested to evaluate their particle generation
properties. This particle generation phenomenon was studied using a custom test
rig utilizing a high precision cleanroom ball-screw to simulate true application
conditions. The ball-screw was tested at speeds from 200, 1,200, and 2,400 RPM
to illustrate the effect of speed on the particle generation across different
applications. This article will show the tendencies of different lubricant
chemistries to generate particles and which ones present advantages of improved
durability and environmental cleanliness for critical processes and
applications.