[203] Introduction to online oil debris monitoring technologies

S Greenfield

Engine & Rotorcraft Health Monitoring, Eaton Aerospace, UK 

Oil debris monitoring (ODM) is one of the earliest forms of condition monitoring, with thousands of examples of application and success since the 1950s.
Formal condition monitoring training often addresses the technology in passing and does not create an awareness of the recent advances made in the automation of debris collection, retention and online analysis.
This paper is primarily intended to educate the younger members of our universities and practitioners entering industry about what oil debris monitoring does, how it does it and how to apply it. This paper will be especially valuable to those who have never had practical exposure to industrial machinery.
The revelations of dirty oil and a magnet can be analysed electronically at the high/safety-critical end to drive predictive maintenance. Or, alternatively, very inexpensively for simple non-critical applications, by the simplest but sophisticated instrument, the Mk 1 human eye.
The technology evolution is rolled out in an easily understandable form, along with benefits and pitfalls explained along the way, from the simplest of beginnings through to the current state-of-the-art online ODM systems.
These enhancements reduce maintenance man hours while giving repeatable results by removing the natural human ambiguity in the interpretation. 
Oil debris monitoring systems (ODMSs) have become the de-facto monitoring system on modern passenger aircraft gas turbine engines.