Machinery Lubrication magazine published by Noria Corporation
Issue link: https://www.e-digitaleditions.com/i/229047
MAINTAINABILITY MACHINE DESIGN FEATURES CORRECT LUBRICANT STABILIZED LUBRICANT HEALTH CONTAMINATION CONTROL ADEQUATE AND SUSTAINED LUBRICANT SUPPLY Properly selected and located primary and secondary live-zone oil sampling valves More accurate oil analysis confirms the right lubricant is in use More accurate oil analysis confirms the health of the lubricant More accurate oil analysis detects and quantifies the presence of a range of contaminants More accurate oil analysis can detect air entrainment issues and thermal degradation/wear conditions Proper installation of magnetic wear debris inspection plugs May reveal inadequate film strength from wrong oil in machine frictional zones May reveal inadequate film strength in machine frictional zones from degraded lubricant (additives, viscosity, etc.) May reveal inadequate film strength in machine frictional zones from contaminated lubricant May reveal inadequate film strength in machine frictional zones from lubricant starvation Online oil analysis sensors Sensors can confirm the use of the right lubricant Sensors can detect degrading lubricant properties Sensors can report the concentration N/A Minimal use of funnels, contaminated fill ports, etc.; contamination control from flushing and filtration Simplified oil change and control of oil level Oil Analysis Contamination Control Maintainability Quick-connects for adding or draining oil, periodic portable filtration and flushing requirements N/A Contamination control prolongs lubricant life Quality headspace management (breathers, headspace purge, dehydration, etc.) N/A Reduced contaminant ingression extends oil service life Reduced water, dirt and process contaminants N/A N/A Contamination control prolongs lubricant life Faster and more effective removal of damaging contaminants Reduced risk of contaminant-induced internal and external lubricant leakage causing starvation issues Suitable performance, quality and location of filters While it may seem to be an oversimplification to reduce lubrication excellence to just four basic objectives, as a practical matter, not much else is required. See the tables on pages 2, 4 and 5 to learn how machine maintainability can be applied in the context of the Big Four. Role of Buyers/Purchasing Before buying new machinery, an engineering specification should be carefully and thoroughly developed. Engineers charged with writing these specifications should be educated on modern concepts in machinery lubrication. Simply working as an engineer or having an engineering degree alone does not qualify. Instead, training by leading consultants and instructors is strongly advised. Training should be followed by certification compliant to ISO 18436-4 and similar standards. Noria recommends that engineering specifications for new equipment only be written by professionals with Machine Lubricant Analyst (MLA) Level II and III certification credentials. A specification should address many, if not all, of the maintainability features shown in the preceding tables. It must also address hardware and design features that are not permitted. These might include ring oilers, drip oilers, screen filters, snorkel vents, high-watt-density tank heaters, long pump suction lines, etc. Consider having the specification carefully reviewed by an outside lubrication consultant, especially for the most reliabilitycritical machines. Remember that the cost of retrofitting needed maintainability hardware will be many times the cost of the same hardware when installed at the factory (as part of the original bill-of-material). Conversely, buying machines stripped to the bones in an attempt to reduce costs is almost always false economy. The astute reliability professional views new equipment in terms of the cost of ownership, not simply the cost of purchase. Most important is the overall machine reliability, which includes repair costs but also equipment utilization (uptime), maintainability (PMs, inspections, etc.), safety and other factors. All of these should drive the business decision to invest in reliability readiness. About the Author Jim Fitch has a wealth of "in the trenches" experience in lubrication, oil analysis, tribology and machinery failure investigations. Over the past two decades, he has presented hundreds of courses on these subjects. Jim has published more than 200 technical articles, papers and publications. He serves as a U.S. delegate to the ISO tribology and oil analysis working group. Since 2002, he has been director and board member of the International Council for Machinery Lubrication. He is the CEO and a co-founder of Noria Corporation. Contact Jim at jfitch@noria.com. www.machinerylubrication.com | November - December 2013 |5