Home        About        Contact
5

Ferrography

One of several techniques for collecting data on the condition of an asset .

For determining the size distribution and type of wear particles as part of an oil analysis program

The basis of modern oil analysis is the use of optical emission spectroscopy (OES) to measure the ppm (parts per million) levels of wear metals, contaminants and additives in oil samples.

Analytical techniques performed on oil samples can be classified in two categories:
  • Used oil analysis - this determines the condition of the lubricant itself, determines the quality of the lubricant, and checks its suitability for continued use.
  • Wear particle analysis - this determines the mechanical condition of machine components that are lubricated. 

Purpose




Candidate Assets
Listed below are some of the different types of candidate assets for oil analysis:

      A.  Mechanical Assets
  • Gear boxes
  • Pumps
      B.  Other Assets


Conditions & Condition Grades

Listed below are the condition grades for this technology.
IDGradeDescription
1ExcellentRated: "No action required"
2GoodRated: "keep monitoring"
3Fairnot used
4PoorRated: "action required"
5Very PoorRated: "urgent action required"



Process
This technique analyzes the particles present in fluids that indicate mechanical wear.  

A. Before Analysis
  • Purchase equipment or engage contractor
  • Train staff
  • Determine sample size, location and interval
B. During Analysis
  • Take the sample
  • Send sample off for analysis  
  • Analyze the results - chemical composition of the used oil
  • Grade the results
C. After Analysis
  • Make maintenance decisions
  • Determine CAPA's, if any
  • Determine next assessment interval



Attributes
Listed below are some of the key attributes of ferrography that should be taken into consideration when integrating this into the overall asset management program:

Evaluation
A comprehensive monitoring program usually includes ferrography (oil analysis).

A.  Pros/Merits
  • It is a relatively simple and cost effective process
  • Other
B.  Cons/limitations



Ferrography as one of the predictive maintenance (pdM) technologies along the P-F Curve in relation to Potential Failure (P) and Functional Failure (F)
Fig. Ferrography as one of the predictive maintenance (PdM) technologies along the P-F Curve in relation to Potential Failure (P) and Functional Failure (F).


Comparing the Maintenance-Repair-Renewal (MRR) trade-offs at different organizations.
Fig. Comparing the Maintenance-Repair-Renewal (MRR) trade-offs at different organizations.


Alignment of the four different types of maintenance strategies across the asset portfolio on decisions that are risk-based and consider the whole-life of assets will result in a maintenance mix that is in conformity with ISO 55001 standards
Fig. Alignment of the four different types of maintenance strategies across the asset portfolio on decisions that are risk-based and consider the whole-life of assets will result in a maintenance mix that is in conformity with ISO 55001 standards.

See also:
Compare with:


(c) Copyright Asset Insights, All Rights Reserved. - "Insight, foresight and oversight of assets"