Most mechanical systems containing parts that are in contact – and move relative to one-another – will require some form of lubrication to maintain good operation. Lubricants generally reduce friction and wear, cool friction zones and transport wear debris from them and, in some applications, transfer power (in power hydraulics for example). To achieve reliable and efficient operation, industrial equipment must be maintained properly.
Well lubricated and managed machines include (but are not limited to): pumps, compressors, gearboxes, engines and drives, turbines and power hydraulics. They operate at their design expectations for the life of the asset and yield very low through life costs, whereas poorly managed lubricated assets do the opposite.
However, simply adding oil or grease to a machine is not enough. Proper lubrication requires a systematic approach that considers factors such as machine type, application, and operating conditions.
CREATING A MAINTENANCE PROGRAMME
There are a number of key factors to consider when drawing up and implementing a lubrication programme. For example, a well-planned maintenance schedule ensures that lubrication is done consistently and on time. The schedule should include a detailed description of equipment, suggested lubricants, and frequency of lubrication.
“Proactive maintenance focuses on a knowledge of potential root causes of failures and eliminating conditions that may lead to loss of performance,” says Wojciech Majka, president and CEO of maintenance solutions provider, Ecol. “With lubricants, there are many factors that can be measured and trended in observations that allow them to perform well. Both lubricant life and component health can be assessed by a well-designed oil analysis programme.
“Knowing the trend of changes in the lubricant’s properties, and accurately predicting its remaining useful life is highly possible,” adds Majka. “Condition-based replacing/replenishment gives substantial cost savings due to better planning of scheduled outages, limiting the risk of lubricant or machine failure and extending the life of the lubricant.”
CHOOSE THE PROPER LUBRICATION
The range of lubricant types available is almost as varied as the number of different systems that exist. However, they can be grouped into generic types that are formulated based upon machinery type behaviours that must be accommodated.
These are typically, engine oils, hydraulics, gear lubricants, turbine and compressor oils, machinery and slideway lubricants, chain oils, bearing lubricants such as lubricating greases and rope dressings.
“All these groups will have numerous sub-groups based upon operational features that are predominantly based upon the operating fluid viscosity and a lubricant’s ability to resist issues that may exist within each application,” explains Daniel Shorten, SME lubrication manager at engineer products company, John Crane. “Engine oils need to manage products of combustion, achieve low emissions standards and stay in grade and functional between oil changes. Hydraulic oils must remain incompressible and maintain internal clearances (stay clean) to ensure they maintain fluid pressure and can run at the designed operational state.”
PROPER APPLICATION METHODS
Proper application procedures are also vital in guaranteeing effective lubrication. This includes knowing the proper amount of lubricant to use, as well as the proper time and frequency of lubrication. “The application of lubricant again depends on the type of lubricant required (e.g. grease or oil), the properties of the lubricant (viscosity of oil; consistency of grease etc.), the amount of lubricant needed to be delivered to the system; frequency of lubrication or oil change, etc,” says Majka.
MAINTAINING ACCURATE RECORDS
Keeping accurate records is crucial for tracking lubrication schedules, the amount of lubricant used and the effectiveness of the programme. This data can help identify potential issues before they become major problems.
Shorten says that this can identify “bad actors” and allows comparisons between different groups of assets: “For instance, which tend to operate outside of the limits where reports are less often ‘green,’ indicating some issue or other,” he reasons. “How do hydraulic systems compare to gearboxes, how do engines compare to turbines – what aspect of the lubrication management activity is lacking in those assets where action is required more often?
“This may require working with your analysis provider to get the data in the right format or you may choose to acquire all the data and populate your own asset database and then compare results across the condition monitoring technologies to look at which are in lockstep, and which are divergent,” adds Shorten (left).
MONITORING AND ANALYSIS
Regular monitoring of lubrication data – such as oil analysis and machine vibration analysis – can help detect potential problems before they lead to failure.
However, both Wajka and Shorten say there is no hard and fast rule about how often data should be acquired and monitored. But it should be often enough to capture meaningful change and allow time for rectification before any deterioration becomes unacceptable.
EMPLOYEE TRAINING
It’s important to ensure that employees responsible for lubrication are properly trained and have the necessary skills to perform their tasks effectively. This includes providing training on lubricant properties, handling and storage procedures, and application methods.
There are many standards, industry guidelines, and OEM recommendations for oil analysis schedules available. Oil analysis labs and lubrication consulting organisations are typically good support partners in preparing tailor-made oil analysis programmes.
“Two organisations providing resources and setting standards and trends in lubrication management are ICML (International Council for Machinery Lubrication) and STLE (Society of Tribologists and Lubrication Engineers),” says Majka. “Both provide certification systems for different areas of lubrication-related specialisations; Machinery Lubrication Engineer (MLE) by ICML and Certified Lubrication Specialist (CLS) by STLE.”
Good lubrication management is the result of the optimisation of several integrated activities and behaviours which are managed in alignment to the overall business strategy and with reference to the overall level of risk aversion of each company.
After site assessment and gap analysis development, it’s possible to assess how to improve the areas targeted for optimisation. Once completed the initial analysis can be revisited and compared. Ideally, financial benefits can be extrapolated and communicated to senior management.
“There is no such thing as best practice at all costs,” says Shorten. “At the bottom there is legal compliance, safety, environment, and local legislation at the top is best practice and somewhere in the middle is the optimal place for each organisation - identifying and then targeting this will lead to lubrication excellence.”
BOX: THE ICML 55 STANDARD
The International Council for Machinery Lubrication (ICML) is a global non-profit organisation that helps lubrication practitioners succeed in their professional careers. ICML certification exams are administered in accordance with ISO 18436 and are available worldwide in multiple languages and in both paper and online formats.
In 2019 it introduced lubrication-specific standards that spell out requirements and guidelines for effective, audit-ready, certifiable management of lubricated mechanical assets. Collectively known as ICML 55, these standards are strategically aligned to ISO 55000 and are intended to support an organisation’s physical asset management plans.
“We took the structure, purpose, intent of the equivalent parts of the ISO documents, translated it for lubrication asset managers, putting enough information and requirements and decision-making points down much closer to where the machinery lives,” explains Paul Hiller, marketing manager, ICML. “Whether or not their company is trying to comply with the broader ISO standard, the ICML 55 asset management standard can help a facility or company develop its own lubricated asset management system.”
Again, Hiller says there’s no one-size-fits-all solution for every programme because there are so many variables at play in a facility/team/machine. However, the guidelines in ICML 55 are built on a comprehensive collection of requirements in 12 interrelated areas that allow a considered approach to each area of the lubrication system and create a meaningful lubrication management plan.