Certified Greases Advance Reliability
EP Editorial Staff | June 1, 2021
Managing lubrication is a primary component of your critical-asset reliability strategy. Unfortunately, ensuring that assets receive correct lubricants at proper intervals is often in conflict with the organization’s desire to simplify lubricant selection and reduce inventory.
Lubricating many of today’s assets can be rather involved, resulting in complex lubricant needs and maintenance practices. According to Chad Chichester, Application Development, Molykote Specialty Lubricants, DuPont, Midland MI (dupont.com), poorly managed lubrication procedures result in lubricant inventory imbalance, i.e., too much use of commodity lubricants and not enough use of specialty lubricants.
In a shutdown (planned or unplanned), turn-around time is short. If the proper lubricant isn’t available, end users search available stock for alternatives that will allow them to get assets up and running. Substitutions such as this result in lubricants being used in conditions for which they are not formulated and/or tested. When this happens, reliability suffers. The lubricant becomes the scapegoat when assets perform poorly, and inventory gets out of whack. The end result is that no one is happy.
Grease selection is a difficult aspect of lubrication management because few understand how grease works. With so many lubricating greases available to a maintenance department, proper grease selection for an asset is predicated on determining whether the lubricant can meet asset requirements. It is often said that 80% of assets can be greased with a commodity grease, while the remaining 20% require specialized greases.
This may or may not be true. Commodity greases may contain rather universal components such as lithium-thickened mineral oils with anti-wear and antioxidant additives. In terms of performance, however, there really is no widely accepted performance specification.
Contrary to that, specialty greases may have very specific performance criteria. Formulations can be so specific that the greases cannot be used across a wide asset base. For example, a grease designed for high-temperature performance may use specialty base fluids and additives that resists heat, but those fluids may not exhibit the required wear performance in other applications. As it pertains to inventory management, having greases that can address a wide range of performance requirements simplifies selection and keeps inventory to a minimum.
NLGI’s (National Lubricating Grease Institute, Liberty, MO, nlgi.org), High-Performance Multiuse (HPM) grease specification delivers performance requirements for greases designed to be used across a wide asset base. HPM bridges some of the gaps between commodity greases and specialty greases, while establishing industry performance criteria otherwise not fully addressed in commodity greases. Note that HPM-certified greases cannot cover all specialty-grease performance requirements. There is still a place for commodity and specialty greases.
Because HPM-certified products are new to the market in 2021, prices are not yet available. Users should consider the total cost of ownership including potential asset failure, preventive-maintenance intervals, and overall inventory costs. While each lubricant strategy is unique, adopting HPM specifications and selecting greases certified to the HPM performance requirements can ease grease selection and have a positive impact on operational reliability. EP
For more information about the NLGI High Performance Multiuse grease specification, visit nlgi.org.