Machinery Lubrication magazine published by Noria Corporation
Issue link: https://www.e-digitaleditions.com/i/1378657
24 | May - June 2021 | www . machinerylubrication.com LUBRICANT SELECTION b) Shown to significantly reduce wear and friction. 4. (Honorable Mention) Dispersed Nanoparticles a) Honorable mention because it isn't widely or commonly used in the industrial theater yet. b) Has been shown to reduce boundary friction, which occurs when a surface is at least partially lubricated, but not so much that there is no direct friction between the two surfaces. Friction Modifiers What are friction modifiers? Sometimes called boundary lubrication additives, friction modifiers are additives such as Molybdenum Dithio- carbamate, a common Extreme Pressure (EP) additive, as well as Zinc Dialkyldithiophosphate (ZDDP), a common Anti-Wear (AW) additive. Don't let the long, goofy words intimidate you — they are commonly referred to as Moly and ZDDP. As a matter of fact, those two perform quite well in conjunction within the same lubricant and increase the efficiency and performance of both the machinery and lubricants. Friction Modifiers are additives that also increase the energy efficiency of machines. ere are three primary types of friction modifier additives as mentioned in our list: oil-soluble organomolybdenum friction modifiers, organic friction modifiers and functionalized polymers. Functionalized polymers are the most beneficial to elastohydrodynamic and hydrodynamic lubricating films (i.e. moderate rolling and sliding applications). However, the oil-soluble organomolybdenum friction modifiers work best in severe hydrodynamic conditions such as a journal bearing's heavy sliding contact points. A recent study done by a leading tribology lab lends merit to ZDDP and Moly being among the most common friction-modifying additive packages. e ZDDP has AW or anti-wear properties and is considered a functionalized polymer in relation to the Molybdenum Dithiocarbamate. What is it about these additives that make them "friction modifiers?" Well, the friction modifiers are kind of like lubrication for the lubrication. ey create a smooth path for the bulk of the lubricant to flow through the top and bottom surfaces, which is called anti-compressive behavior, which does exactly what you would expect: it creates the opposite effect of compression by utilizing polarity in the lubricant. ink of it like two magnets' like poles resisting each other, just not as strong. Instead of sucking the surfaces closer together, friction modifiers assist in keeping the surfaces apart. You would be much better off using a good quality, properly formulated and balanced lubricant from the start. One of the first steps in accomplishing this is to make sure the lubricant has the proper viscosity and load-carrying capabilities. Remember, it is better to have your equipment operating with a full fluid film separating its moving parts rather than relying on a friction barrier under boundary conditions. So, in the end, are friction modifiers right for your lubrication needs? You now have the knowledge to help make that decision for your application. ML References 1. Loren Green "When and How to Use Friction Modifiers" https://www. machinerylubrication.com/Read/30336/friction-modifiers-use 2. Noria Corp. https://www.machinerylubrication.com/Read/29181/reduce-friction-surfaces 3. Friction Nemesis by Bennett Fitch About the Author Paul Farless is an industrial service technician for Noria Corporation. His duties include collecting data and preparing reports for the engineering team. Prior to joining Noria, Paul worked as an automotive maintenance technician for an auto-repair service company. He also served four years in the U.S. Navy as a gunner's mate third-class petty officer and as a seaman deckhand, where he was responsible for the troubleshooting and maintenance of electrome - chanical and hydraulic systems. A detail-oriented team player, Paul works well in fast-paced environments and uses his military background to excel and maximize efficiency. START YOUR FREE SUBSCRIPTION www.machinerylubrication.com