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With increasing demands for profitability, yet with limited markets, businesses are seeking internal measures to reduce operating costs in the manufacturing and service sectors. According to business experts, a 10% internal cost saving is equivalent to the profitability generated by an in crease in sales of 40%. One of the key areas of focus is the Maintenance function. However, the usual approach to reduced maintenance through buying cheaper assets and spares will result in unreliable machines, with short-term savings resulting in long-term expenses of rectification of neglected systems.

 

Smart maintenance allows for better quality of attention, yet with a long term, sustainable reduction in maintenance overheads. In the early part of my career in mechanical engineering, the iron ore mine and processing plant in which I spent my training period attained a 50% increase in productivity, yet with a sustained 50% decrease in maintenance costs. Much of this was achieved through a strategy of implementing Proactive Maintenance with a strong focus on lubrication.

 

In the last 20 years Reliability Centred Maintenance (RCM) has become the norm for selecting an appropriate and optimised maintenance strategy for machinery. RCM considers the criticality of the machine to the business, and the maintenance strategy selected will be either:

 

• Break-down

• Scheduled

• Predictive

• Proactive

• Or require redesign

 

Breakdown maintenance is, as the name implies, a strategy of awaiting breakdown and acting in response to that. This is fine on low priority machines where capital costs and criticality to the process are unimportant. In lubrication terms, this is similar to simply changing the oil when it appears dark, smelly and gritty - the lubricant has recognisably failed, or even when the machine is recognisably failing. There is no planned activity relating to the lubrication schedule, nor an immediate consequential failure process resulting from that breakdown of the lubricant. But the signs will be there that the machine is suffering acutely as a result, and the experienced maintenance engineer may not associate those symptoms with the actual cause of poor lubrication.

 

In practice, very few maintenance engineers will operate a policy of breakdown strategy with respect to the oil. More realistically, many maintenance engineers will simply rely on a schedule of lubrication activities - a schedule-based strategy. The schedule may be based on recommendations from the lubricant supplier, or the OEM, or both. The schedule will often as not be conservative and so lubricants with a reasonable remaining life may be disposed in order to fit with an historical schedule, or current downtime scheduling, despite the continuing improvements in oil performance offering longer service life. For small volume, non-critical machines, this policy probably works best, but for larger volumes it can lead to expensive waste.

This is where the process of condition-based maintenance strategies applies, and where the real cost savings can be applied. These strategies are a matter of predicting problems, and seeking to monitor root causes of failure, and considering redesign to eliminate repetitive failures. Oil analysis has a role to play within this, both at a predictive level and at a proactive level. More importantly, lubrication management should be proactively based, thus eliminating the root cause conditions that can lead to lubricant and machine failure, or short service life.

 

It is important to consider a few basic rules of a sound lubricant strategy. These basic rules are fundamental in most aspects of maintenance but are worth repeating here in the sense of the lubrication parallel.

 

By buying cheap lubricants and ignoring the basic fundamentals of lubricant management, this often leads to breakdown scenarios where machines fail to achieve reliability and maximum potential life, and the consequences of the potential breakdowns are catastrophic. However, it is important to consider the right lubricant and lubrication activity to meet the demands of that machine's design, a process of optimisation.

 

Not bothering to do essential and frequent root cause focussed checks on the lubricant and machine, in order to save time, will lead to guaranteed reduced life of the lubricants and the machinery. The inspection process may be a simple site based inspection of the oil levels, or the colour of the oil, or it maybe oil analysis with a focus on contamination monitoring and lubricant condition analysis.

 

Ignoring basic operating system parameters such as temperature, flow rate or pressure that is off specification may suggest a lubricant or machine fault.

In order to maximise the machine and oil potential life it is important to ensure the equipment is operated within the design capability. However, with production demands, this may not be easily achievable. Therefore redesign is a possibility, either as an upgrade to the lubrication aspects of the machine or as a redesign of the system itself. However, at a basic level, before considering expensive re-design under these increased load conditions, ensuring that the machinery is properly aligned, balanced, and fitted with quality components is crucial. Moreover, increased frequency of these checks of the lubricant and machinery are necessary under these demanding conditions of increased production.

 

The issue in all of this is that if the plant is to increase its productivity, yet retain, or even improve on its reliability, and gain life extension over current machinery service performance, then there are some basic principles that must be followed.

 

• Select appropriate, quality lubricants and components that meet the demands of the system design to ensure optimised reliability needs - do not buy from the cheapest supplier.

• Ensure that all the root cause conditions are set correctly prior to commissioning or before start-up. In lubrication terms, that means ensuring a supply of clean, dry and cool oil, which will mean addressing such issues as storage, handling and dispensing practices.

• Undertake regular checks of any root-cause conditions to ensure these are not beyond acceptable limits during machine operation.

• Keep production within the safe limits of the component capabilities to avoid accelerated wear or catastrophic failure. This is often not an option when maintenance must bend to production demands, so the above options are really the only way forward.

 

There are also some basic issues such as ensuring that lubrication and inspection tasks can also be safely undertaken during the machine run-time rather than requiring downtime to do these basics.

 

Figure 1 highlights the importance of spending time on machines and lubricants that are not yet broken. In breakdown maintenance, much time is wasted through not having sufficient planning time and as a consequence valuable maintenance resource is left sitting whilst parts, tools and even contractors are found before "spanner" activity can even start to begin.

 

A Planned Maintenance strategy reduces the wasted time, and improves the planning activity, but in some cases, the actual act of maintaining a machine can induce problems through lack of training or poor quality of replacement parts.

 

Where condition-based maintenance strategies really offer a benefit is providing a "crystal ball" to look further ahead at the work that may be required, thus improving planning activities. This makes more efficient use of the actual maintenance resource. But the only way to achieve this is through frequent inspection and sampling, and the smart approach is to ensure these are undertaken during machine operation, whether by the maintenance or, better still, by the operations staff.

 

A proactive strategy, will further improve this, not only through eliminating failures but also in freeing up maintenance time to shift into a "fire-prevention" role rather than that of "fire-fighting". In some cases, this can be like employing an extra 20 members of staff without actually recruiting anyone. It's called accessing the "Hidden Workforce". The consequential gain in productivity is also known as accessing the "Hidden Factory".

 

Proactive strategies seek to extend machine and component (including the lubricant) life, and minimise problems associated with their reliable operation. The benefits of this are actually far reaching, providing financial gains in areas often overlooked. For example, in the case studies in which I have participated, it is found that frequent benefits are found in the following areas as a result of a sound lubrication maintenance and reliability strategy:

 

• Improved Health and Safety with an associated risk cost reduction. More inspections with minimal maintenance intervention will reduce exposure of staff to risk associated tasks.

• Improved Environmental compliance within ISO 14000 series. Apart from the image perception of the ISO 14000 series for a company, changes in practices can again minimise risk costs associated with fines and penalties. In addition, sound lubrication practices can minimise energy consumption (Climate Change Levy) through more efficient manpower and equipment usage and minimised heavy maintenance tasks.

• Compliance within ISO 9000 which now requires maintenance tasks, including lubrication activities, to be written and audited for completeness.

• In the Pharmaceuticals and Food/Beverage markets, better practices will again minimise risks associated with product contamination, reducing risk-based costs.

• A defined lubrication strategy will further allow employee development by setting out the task and education training requirements for personnel, and offer a company a route for lubrication engineers to follow in career development.

 

A properly designed lubrication management strategy that fits with the maintenance strategy developed for a site will offer far reaching benefits and can, in the case of some plants where I have been involved, avert a crises resulting in plant closure!

 

There is a lot more to be said on the topic of reliability and, in fact, it is the subject of an excellent two-day course aimed at senior management. But please feel free to contact me with your views, thoughts and questions.