Over the past decade the "LEAN" phenomena has allowed manufacturing industries to greatly increase their levels of profitability and productivity. Combined with other initiatives, such as TPM, LEAN has allowed these companies to focus on the efficiency of their production processes.

The Merriam-Webster online dictionary defines efficient as being "productive without waste". In recent time we have seen many consultancies and companies starting to talk about terms such as "LEAN Maintenance", an attempt to bring the same efficiency improvement approach into the world of physical asset management. The thinking behind this is laudable, and many companies have been able to benefit greatly from the waste elimination focus that LEAN fosters.

The problem is that the same fundamental principles have been bought directly from the production environment into the asset maintenance environment. The same seven areas of waste, the same initiatives such as just-in-time inventory management, and the same sort of focus on the day-to-day without including a longer term focus.

(In the most extreme cases it appears as if LEAN seems to be a metaphor for every buzzword and service that a consultancy has to offer - but that would be cynical)

"So what?" you say. "Why should maintenance be any different?"The reason why a lean maintenance approach cannot just be a mirror image of a lean production approach is because the business dynamics of asset maintenance and those of production are fundamentally different.

A short summary of the differences is below, but in my new book, tentatively titled Asset Resource Planning: Lean strategies for efficient maintenance, this is explained in a lot more detail.

• Production plans are driven by sales forecasts and in the nearer term by sales orders. This means they are driven by an exact schedule of works. Asset maintenance, on the other hand, is driven in part by a schedule of routine work and in part by the likelihood of failure of the assets under management.

This means that initiatives such as JIT inventory management have only a limited ability to assist the efficiency of the maintenance process. Issues such as Just-in-case inventory management are far more important.

This has implications not only within the area of operations, but throughout the entire supply chain. Often the improvement of a supply chain is based on "how we buy", the probabilistic nature of asset maintenance means also that we need to be thinking about "why we buy".

• Production efficiency is gained almost entirely through present operations. So to be “productive without waste” is thought of in terms of the day-to-day activities involved in managing the production processes. (And rightly so)

In asset maintenance being “productive without waste” has an additional perspective to it, that of time. A large part of any asset maintenance spend over time relates to asset replacement and refurbishment intervals. Depending on the type of plant these are often very large scale costs on a par with the initial equipment purchase in terms of magnitude.

So “productive without waste” means not replacing these too early, and often in not allowing them to fail completely before they fail. So to be truly efficient we need to control a range of issues related to asset use, type, expected life and other issues.

This is significant and reaches outside of the maintenance function itself. For example; a machine that is subject to regular overload situations is likely to have a shortened life expectancy, meaning that capital will need to be spent on it at an earlier stage than previously thought.

• The last issue we will explore here is that of data management and collection. Improvement of production processes can often be made through recording and acting upon dynamic operational information.

In asset maintenance this also has its place, but as we can see from the issue above we also need to be able to confidently forecast spending in the future and how that is affected by current activities.

This requires data other than the dynamic operational data. It also requires static data on equipment type, location and age; as well as a range of data regarding failure rates, asset condition and other areas.

While this seems straight forward, when this task is not correctly managed it can be a tremendous strain on the resources of the asset maintenance department. Particular when they end up spending a lot of time and money collecting data that is of no use to them!

So where does this leave us? If we believe firmly, as I do, that LEAN maintenance needs a different focus that LEAN production, what should it be?

Over the years I have put together a list of eight areas where the majority of waste in maintenance occurs. Again it is difficult to go through it in detail here but hopefully it will give you the picture.

While some of these are the same as those in a standard LEAN approach, there are some notable differences. Some items have been deleted from the list of wasteful activities, while others have been added.

• Unproductive work – Efficiently doing work that doesn’t need to be done!
• Delays in motion – Waiting times, delays waiting for parts, machinery, people, etcetera
• Unnecessary motion – Unneeded travel, trips to tool stores or workshops, looking for items, moving mobile work stations around without good reason.
• Poor management of inventory – Not able to have the right parts at the right time. A complex area that can cause many of the other areas of waste on this list.
• Rework – Having to repeat tasks, or do additional tasks, as a result of poor workmanship.
• Underutilization of people – Using people to the limits of their qualifications, not to the limits of their abilities!
• Ineffective data management – Collecting data that is of no use, or failure to collect data which is vital. Both of these are parts of this area.
• Misapplication of machinery – Incorrect operation or deliberate operational strategies leading to maintenance work being done when it needn’t be.

This is a topic we could discuss for a long time and it is one that will no doubt cause a lot of disagreement and hopefully some debate. But once you sit down and really look at the business of maintaining assets, how it works and what the important elements are, I believe you will agree with me.

If we really want to deliver “productivity without waste”, or efficiency, in asset maintenance, then we need a different version of LEAN; one that takes into account the unique business dynamics of the area that we work in.

Good luck with your efficiency initiatives!

First published at www.plantservices.com

Recently I was asked a question by one of the people in my mentoring class from the utilities industry of the UK. On face value it appeared to be an obvious way of looking at things:

“If you have been performing condition monitoring for a while, say two years, and you have found nothing, then you should be able to extend the frequency of the task or eliminate it altogether right?”

His goal was to see how the company could reduce its maintenance costs through elimination of wasteful and unnecessary activities; a noble enough goal and one that is shared by many managers around the world. Also, the logic sounds like it should be right. If we are doling this and finding nothing, then why are we doing it?

Many people think this way, and many managers take decision based on this sort of approach; unfortunately it is the exact opposite of how condition monitoring and asset maintenance principles actually work!

To get to the bottom of this seemingly counter-intuitive approach we first need to understand some of the basics of why a condition monitoring task would be chosen, and then understand how the frequency of this task could be determined.

RCM points us to two sets of criteria that a task must comply with before it can be selected. Firstly it needs to be “applicable”; in RCM terms applicable means that it is able to be applied physically. The other test if to see whether or not the task is “effective”; meaning whether it is likely to reduce the consequences of failure, or probability, to a level that makes it worthwhile applying the task.

The first issue, applicability, is where we find the answer to our question. One of the first criteria in this issue is whether or not there is a “P-F interval”, establishing what it is and whether or not it is consistent.


The P-F interval is the time between when the potential-failure (P) is able to be detected, and when the functional-failure (P) occurs. The graphic above should make this clearer. This has been copied directly from the original RCM report.

Here we can clearly see how the P-F interval informs our decision on frequency of condition monitoring tasks. It shows a deteriorating resistance to failure overtime, and a range of check points throughout that time period.

This is a good description for just about any failure that condition monitoring could be useful for detecting, in this instance we will look at the failure of a roller bearing due to metal fatigue, using the points on the curve as a guide.

Metal fatigue is the effect of taking a paper clip and folding it back on itself several times. What happens? The metal within the paperclip weakens over time, becomes fatigued, and then breaks altogether. What we don’t see are the range of microscopic effects and events that lead up tot eh paperclip breaking.

It is the same with a bearing. As we have reviewed previously, over time the metal within the races, balls and other elements weakens. (We will avoid getting into the discussion about why it would weaken for now) While it remains sub-surface, that is within the walls of the race for example, we often do not even know that it is developing, nor are we able to do anything to detect it.

However, once it actually breaks the surface, say at point B, then we can start to detect it via changes in vibration levels. As the resistance to failure deteriorates even further, point C, then we may be able to detect it via different means. Changes in heat, noise, amperage draw, and equipment performance are all examples of differing means to predict failure.

The time remaining between when we actually predict the warning signs of failure, and when it actually fails functionally, (no longer able to do what we require of it), is the P-F interval.

So, the frequency of any task that sets out to detect the warning signs of failure needs to be less than the P-F interval! This is a fundamental issue and one that is often misunderstood. Working through the criteria for applicability and effectiveness are what guides us as to whether or not to apply a task, not whether we find anything or not.

Our decision logic (applicability and effectiveness) have already told us that it is wise for us to apply the task, so we already know that if we don’t predict it then we will be faced with undesirable consequences of failure.

If we take it upon ourselves to lengthen the frequency, or worse to remove the task altogether, merely because it has not detected anything yet, then we are setting ourselves up for an unpredicted failure. For example, if we extend the frequency to 6 months or greater, then we will detect the warning signs of failure based solely on good fortune. If we remove the task altogether then sooner or later we will experience the consequences of failure that this task was designed to protect us from.

I hope this is of use in either defending the condition monitoring tasks you already have in place, or in helping you to determine the frequency of on-condition tasks that you are currently working with. There are a whole range of additional factors that should also be considered such as the accuracy of the task, the severity of the consequences etcetera, but this should help as a basic guide.

Best of luck!

Goals and resolutions are a part of the New Year rituals all over the world and the growing field of asset management is no exception to this.

If you have just discovered the Modern Asset Management Blog I hope you will recommend it to your colleagues as a source of independent facts and opinion.

So, as asset managers what are some of the ways that we can get a grip over our costs rapidly, without embarking on a full scale implementation project? As with most other things there are a bewildering array of options and opportunities; however this list comprises a few short and easy to implement techniques that I have picked up over the years.

I hope it is of some use to you.

1. Basic capacity scheduling: Capacity scheduling is probably one of the easiest and most effective things that you could implement within a short time frame. And while it requires a lot of discipline, it shouldn’t require a great deal of additional resource to get started.

The basic concept of capacity scheduling is easy enough. Work out what level of resources you have available to you, then make sure that your work schedule for a period uses all of the available time.

Doing it in reality does present a few challenges. For example, you will need to ensure that available hours are accurately calculated and do not represent the total hours. A fair way to begin this process would be to:

• Understand how many work hours you have available per person. (Subtracting breaks, meetings, vacations, training and other issues)
• Take off, say, 5% for time that will be used helping other teams
• Take of, say, 5% for time that will be required in dealing with reactive work.

Once the available time is accurately being forecast, then you can turn to the task of filling the schedule.

The first tasks to go into the schedule are the routine tasks. These are the standard routine maintenance tasks that will need to be done automatically. These are the highest priority and are not things that should be considered last. (There is a whole discussion on this that will be gone into at a later date on this blog)

Once the routine tasks are in, and the worker availability is calculated, we can then finish the capacity schedule. This is done by adding reactive work orders, from highest priority to lowest priority, until the capacity schedule has been filled.

There are a few things that you will need to do before you can really get this one into your day-to-day processes. Namely;

Ensure your hours worked and absence management systems are updated regularly and can be relied upon as an accurate forecast of worker attendance.
Ensure your routine maintenance schedules are optimised. Without this they will continually be put back because there will be a lack of belief in them, and a lack of understanding of what they are designed to do.

Ensure your estimates are close to representing reality. There is no doubt that they will change as time goes on and this will only be a beginning point.

Ensure your entire backlog management processes are up to scratch. This is going to be an exceptionally difficult area as it is one that will need to involve the entire workforce.

Implementing capacity scheduling will also challenge the connections you have between the planning and execution arms of your maintenance functions.

In all it is an area that can get you moving quickly, with a mild level of effort, but a lot of discipline to follow it through.

2. Precision alignment: A major source of unnecessary spending within the maintenance area is due to misaligned equipment. In particular early life bearing failures, increased wear of coupling components, excessive forces (radial and axial) on the bearings leading to shorter life also, and potentially premature seal and shaft failures.

Here are some quick tips that may help you:

• A quick check over a section of expensive or critical assets could indicate a need for a wider alignment audit. It is wise to do this on an annual basis as there are a lot of things that can contribute to misalignment.
• Always check on motors and pumps at least three to six months after they have been installed to allow for settling of the foundations
• Gain an understanding of how to use modern condition monitoring techniques (vibration analysis and frequency spectrum analysis) to distinguish between misalignment and other causes of vibration.

3. A few indicators: Some dramatic results can be gleaned from correctly implementing and using measurement programs. (See The Maintenance Scorecard) here are a few quick options for you:

• Implement an age versus priority metric. This is a vital metric for making sure that your backlog management, scheduling and execution are all doing their part to keep downtime low, uptime high, and risk levels under control. (This is a very good leading metric also)

• Establish the link between production and maintenance through use of unit cost indicators. (A good proxy for cost effectiveness)

• Start to measure schedule compliance as a means of determining risk of failure, not merely of determining how well we execute maintenance work.

There are many others that can be done quickly, however these are a few that I have successfully implemented many times; often with dramatic effects for a minimal level of effort.

Good luck!