What is autonomous maintenance (TPM)?

Autonomous maintenance is one of the 8 Total Productive Maintenance (TPM) pillars, it aims to give both competence and responsibility for routine maintenance, such as cleaning, lubricating, and inspection to operators.

The aims and targeted benefits of autonomous maintenance

The ultimate goal of Total Productive Maintenance is to enhance machines’ effectiveness. TPM is a participative approach, involving all stakeholders and taking into account all aspects of maintenance. In order to achieve this goal, TPM is split in 8 pillars or topics. Autonomous maintenance is one of the 8 and is about simple mundane tasks, but having their importance nevertheless. The expected outcomes are:

  • Operators’ greater “ownership” of their equipment
  • Increased operators’ knowledge of their equipment
  • Ensuring equipment is well-cleaned and lubricated
  • Identification of emergent issues before they become serious failures
  • Freeing maintenance personnel for higher-level tasks

Operators’ ownership

Operator’s ownership of their equipment is meant to close the divide between Production and Maintenance in cases where the first claim “my job is to produce” and the second “my job is to repair”. This is mainly the case when production staff is incentivized on production output and maintenance is jealous about keeping its technical skills and prerogatives.

What happens then is that production operators do not usually care much about the equipment and machines they use and are prone to trespass speed limits, for example.

As they are not supposed to do anything about the machine breaking down, they soon find out that breakdowns are opportunities for an extra break, hence an extra smoke, one more coffee and so on.

As a result, machines stops last longer as they should: waiting for maintenance staff to come, discover the cause of the trouble, fix it, waiting for the operators to come back and resume production.

It can go the other way when production is strongly incentivized on units produced: any stoppage or breakdown jeopardizes the bonus and is immediately resented when maintenance doesn’t fix the problem fast enough.

What TPM is trying to do: give operators a sense of ownership of their equipment in order for them to take care, use it well, help maintenance technicians to find the causes of breakdowns by summarizing what happened before, and so on.

In order to achieve this, training must be delivered to both production and maintenance staff, focusing on the required cooperation for the sake of overall performance improvement. It will be a win-win cooperation: operators enriching their jobs with technical aspects and maintenance technicians being freed of low-qualification tasks for a better use of their real technical expertise. However, this must be done step by step.

Increasing operators’ knowledge of their equipment

Operator will use their equipment and machines correctly if they are trained not only for the use, but also a bit further into technical details. When operators have a basic understanding of how a machine works, they may be able to discover some causes of malfunction by themselves and give precious indication to maintenance team. With this focus, downtime can be reduced as maintenance does not have to go through a full investigation. If operators show interest and abilities, they may be trained further, to a point they can help maintenance with repairs, preventive maintenance tasks, adjustments, etc.

In my years as production manager with Yamaha, we brought teams of ladies to take care of the maintenance of automatic electronic components insertion machines. These ladies started as operators without any technical background, only feeding the machines. Step by step we trained them to take care of simple cleaning tasks, then adjustments, later exchanging more and more complicated mechanisms and finally be involved in major repairs.

Ensuring equipment is well-cleaned and lubricated

Before dreaming of repairing complex equipment, the journey starts with more mundane but important tasks: cleaning and lubrication.

But it’s more than that. Autonomous maintenance is about passing over  to operators the basic cleaning of the machines, lubricating and oiling, tightening of nuts and bolts, etc.

With these new tasks, operators will soon be able to take over daily inspection, diagnosis of potential problems and other actions that increase the productive life of machines or equipment. With appropriate prior training, of course.

Identification of emergent issues before they become serious failures

Cleaning and lubrication by operators is not a trick to reduce manpower costs by pushing tasks to lesser qualified people. On the contrary: TPM considers daily cleaning as an inspection and operators as subject matter experts. Indeed, operators using the machines and equipment daily are the best qualified detectors of early signs of problems. While cleaning they can detect: wear, unusual noises, vibrations, heat, smell, leakage, change of color, etc.

Using the machines frequently, they know best what is “as usual” and what is unusual. Someone hired only to clean and lubricate machines without using them would not be able to notice the forerunning signs of potential big trouble.

This daily inspection is key to reduce breakdowns by keeping the machine in good condition and by warning early – before breakdown – in order to remedy swiftly to unusual forerunning signs.

Freeing maintenance personnel for higher-level tasks

Putting skilled professionals in charge of challenges matching their expertise is certainly more attractive than asking them “to clean up other’s mess”, as maintenance staff frequently complain. Therefore the reluctance to train production operators for simple tasks and hand those over should not be a big deal for maintenance techs.

Production management should also see the opportunity to have better technical support for improvement and repairs, as skilled technicians are made more available. Of course, this comes at the expense of some daily minutes devoted to take care about machines instead of producing parts. In the long run, this should be a good deal, because less breakdowns, less scrap, fewer minor stops and faster changeovers thanks to technical improvements will pay back in productive capacity.

Finally, for production operators, the deal is to enrich their job with more technical content. For those immediately claiming acquisition of new skills deserve a pay raise, they should first consider that taking care of machines and equipment they are in charge is a basic expectation, not an extra requirement. Time will be given to do the daily maintenance routine. For operators it’s a shift of occupation content a few minutes a day.

Now this said, the question of a raise is to be considered in the context.

About the author, Chris HOHMANN

About the author, Chris HOHMANN

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Can Industry 4.0 rejuvenate Total Productive Maintenance?

In this post:

The youngest among my blog readers may not understand what I mean with Total Productive Maintenance, this pre-Lean management approach to maximize machines and equipment effectiveness and aiming to improve companies’ performances.

TPM in a nutshell

In a nutshell, Total Productive Maintenance or TPM in short, originated in Japan, 1971. It was a participative spin-off of the american Productive Maintenance (a mix of maintenance policies to maximize machines’ availability and effectiveness), aiming to minimize all kind of losses by involving every department and everyone.

TPM had its heyday in the 1985-1995s in the western companies and failed to get mainstream despite the efforts to rebrand it Total Productive Management. The original name and much of the content, even so transposable to almost any activity, was too much linked to industrial machinery maintenance.

Total Productive Maintenance gave way to Lean Manufacturing and somehow got absorbed by Lean. TPM brought Overall Equipment Effectiveness (OEE) indicator to the world, a still very popular KPI nowadays.

Industry 4.0 and Total Productive Maintenance 2.0?

My basic assumption for this prospective thinking is that industry 4.0 environments will be highly automated so that the human factor will have lesser impact on the machines / cells / lines /workshops performance. Conversely machines’ utilization will regain focus.

Performance is determined by market requirements, but it will continue to be a mix of responsiveness, speed (time to market, lead time… ) and quality, with a higher expectation for agility than today. Costs may come second when dealing with high customization.

Performance will be mainly driven by machines’ availability, speed and yield, the latter being roughly the right first time rate. In other words OEE.

Availability is key for agility and responsiveness. This stresses the need of preventive maintenance and quick changeovers. Preventive maintenance starts with daily cleaning and inspection in order to keep all equipment in operational state and detect any wear or damage early. Some equipment will probably also need periodic calibration and geometry checks to ensure accuracy e.g 3D printing.

These tasks may be passed to former operators now converted into level one maintenance technicians. Further more in-depth periodic inspection will also be required by more expert staff that can be either company’s own or third-party. This reminds of the ‘autonomous maintenance’ pillar of TPM.

TPM autonomous maintenance in 4.0 environment

Autonomous maintenance intent was/is to give operators greater “ownership” of their equipment in order for them to take care and use responsibly. By increasing operators’ technical knowledge of the equipment they use and entitle them to do the simple daily maintenance tasks, autonomous maintenance aim was/is to:

  • ensure equipment is constantly well-cleaned and lubricated
  • maintenance experts’ time is freed for higher-level tasks
  • emergent issues are noticed and identified before they become failures
  • enrich the job of production operators.

if operators showed interest and demonstrated capacities, they could be trained further and assist maintenance experts for more complex maintenance tasks and even take part in repairs and overhauls.

In a industry 4.0 environment, the content of this ‘autonomous maintenance’ pillar of TPM must be adapted to the new technologies. It could encompass data management, using the digital twin, simulate… and require digital literacy.

In a industry 4.0 environment the role of operators as machine feeder, unloader and tool fitter may be marginalized thanks to automation. The jobs for production operators as we knew them may diminish and new jobs will be created requiring different skills and abilities, but not as many.

I could imagine recycling some of the former production operators into ‘autonomous maintenance’ operators, but my guestimate is that one operator could take care of 5 to 20 3D printers. The operator-to-equipment rate compared to traditional manufacturing will surely shrink. Besides, everyone will not show the necessary capacity to evolve.

Can Industry 4.0 rejuvenate Total Productive Maintenance?

As for the autonomous maintenance my guess is that chances are good, even so it may need to be updated in a new 2.0 version fitting the new technical environment.

Focus will be on equipment because of the investment, because of managers in love with tech, because equipment performance will be the main driver for (a production) company’s performance, and for probably more reasons.

For the other 7 traditional pillars I am not sure. You’re welcome to share your own thoughts.

About the author, Chris HOHMANN

About the author, Chris HOHMANN

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The man-machine system performance

When looking for performance improvement of a man-machine system, too often management puts emphasis onto machine or technology at large, ignoring the fact that humans associated with equipment, machines or technology form an interrelated system and consequently humans are the discriminating factor.

The fallacy of trusting the latest technology

There is a strong belief, backed up by vendor’s marketing, that the latest state-of-the-art high-tech equipment will bring a breakthrough in performance. This is welcome news for executives struggling to keep their organization up with competition and seeking a significant performance uplift.

Production managers, industrial engineers or system designers are big kids loving high-tech expensive toys, geeks of their own kind and dreaming to get the latest, biggest, fastest piece of equipment.

Once investment made, performance does not skyrocket though.

What happened?

Management blindness

Management ignored the human factor, i.e. people put in front or in charge of the new machine, the latest technology. An operator and his machine for instance are a system.

The overall performance of this system is determined by the human-machine pair, and guess what, the most variable and hardest to control is the human factor.

Unlike machines, humans have their moods, their worries, variable health and morale, private concerns and motivation issues. One day fine, the other day down.

Humans are not equal in competencies and skills. Some learn fast, some learn slow and some never really get it.

So what’s the point giving the latest top-notch technology to someone not competent or not motivated?

Yet this is most often what happens. Management assumes that the best of machines will make the difference, totally ignoring the influence of the people in charge.

The irresistible appeal of technology

Most decision makers and managers have some kind of hard-science background, got their degrees in engineering or business management. They were taught the robustness of math, the beauty of straightforward logic and to trust only facts and data.

When puzzled facing in real-life the highly variable and elusive nature of humans, they have a natural tendency to prefer hardware. This is something that can be put into equations and eventually controlled. This is what they are most familiar with or at least the most at ease with.

Humans are only trouble. No equation helps to understand their intrinsic drivers nor to reduce their variabilities. This is all about soft skills and psychological factors. Nothing for engineers and hard science-minded people.

Instead, they put a strong hope that the best and latest technology will trump the human factor, reduce it to a neglectable pain. But this never happens.

So again: what’s the point giving the latest top-notch technology to someone not competent or not motivated?

Leveraging performance

In order to improve a man-machine system, it is key to first have a look on the human factor, the most important one. Make sure competency is granted. If someone lacks the necessary competencies, performance is nothing than a matter of luck.

Beware of incompetent but highly motivated people though. In their desire to do well, they may have unknowingly potentially dangerous behaviours and/or take bad decisions. These motivated ones are likely to learn, do thing right but need training and guidance.

Not motivated incompetents are not likely to take any initiatives. They are the manager’s pain and burden and giving them better, faster machines won’t help. What’s worse with not motivated incompetents is passive aggressive behaviors that can lead to potentially dangerous situations as well.

Competent but not motivated people need and probably deserve management’s attention in order to get them into the winning quadrant of the competency-motivation matrix, aka skill-will matrix (top right).

There are the competent and motivated people who do their job effectively, often efficiently and without bothering anybody.

Competent Find a driver or a whip No worries
Incompetent Long way to go… Potentially dangerous good will
Not motivated Motivated

Competency-motivation matrix from a supervisor perspective

It is with these competent and motivated people that the limits of machines or technology can be found, as they will use them properly and purposely. Even when these performance limits are reached, it’s not certain that better planning and/or better organization cannot get more performance out of the system.

Think about quick changeovers and all capacity that can be regained applying SMED methodology, or rethinking maintenance in Total Productive Maintenance (TPM) style.

Wrapping up

When facing the challenge for improving performance, considering the way operations are done should be the first step. The second is to remember than investing in people is usually cheaper and more effective than investing in technology in first place, because a well utilized outdated machine will have better yield and be way cheaper than a poorly utilized state-of-the-art new one.

“Unfortunately” for tech-lovers who would prefer new “toys”, this investment in humans has to be a substantial part of their manager’s daily routine.


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Why No One Talks About TPM Anymore?

Total Productive Maintenance (TPM) was a big thing in the late 1980s, got lot of attention, tried to go from “maintenance” to “management” and finally faded out into oblivion.

This analysis is my own, you may respond in comments.

Total Productive Maintenance (TPM) originated in Japan with Nippondenso in the 1960s and is an evolution from Preventive Maintenance principles introduces to Japan from the USA.

TPM grow popular in the west with other “Japanese methods” in the 1980s when Toyota Production System (TPS) was not known nor the word “Lean” used for manufacturing.

TPM in a nutshell

TPM proposed a framework of 8 pillars aiming at getting the most out of lines, machines and equipment especially by reducing machine downtime and increasing machine availability. The 8 pillars are:

  • Autonomous Maintenance
  • Planned Maintenance
  • Quality Maintenance
  • Focused Improvement
  • Early Equipment Maintenance
  • Education and Training
  • Health, Safety & Environment
  • TPM in Office

Their naming and order (may) vary according to sources. “Six big losses” were identified as obstacles to better machine effectiveness:

  1. Breakdown losses
  2. Setup and adjustment losses
  3. Idling and minor stoppage losses
  4. Speed losses
  5. Quality defects and rework losses
  6. Startup / yield losses

These six losses’ measurement were combined into a single KPI: Overall Equipment Effectiveness (OEE), still very popular and widespread in industry.

TPM was striving to improve OEE by developing the personnel’s maturity about the 8 pillars and reducing the 6 losses.

Early years till today

TPM brought tremendous improvements in operations and work conditions. Despite the machine-orientation TPM had also influence on operations management and at some point was supposed to translate into broader application, attempting to go Total Productive Management.

Alas, TPM was strongly machine shop and shopfloor connoted and never got much attention outside of these playgrounds. Furthermore, Lean became highly fashionable and easier to transpose in any activity, thus got all attention.

In my humble opinion TPM was bound to fail from the moment it was presented as a maturity-driven approach to improvement, requiring organizations to go through a multiyear program, step by step implementing every pillar. The pitch was that eventually performance will raise once personnel is trained and gets experienced with TPM. After some years of continuous effort, the organization will be mature enough to apply for one of the PM awards awarded by the Japan Institute of Plant Maintenance (JIPM) or local representative body.

Of course, the journey toward maturity would require consultants’ support, making it a long, costly and still risky one. With the competitive challenges getting tougher, few CEOs would commit to such a slow approach with questionable ROI, very much machine-effectiveness oriented.

Nowadays OEE, quick changeover and setup techniques like Single Minute Exchange of Die (SMED) are seen as part of the Lean Body of Knowledge and TPM very seldom mentioned.


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The very minimum to know about Overall Equipment Effectiveness (OEE)

Overall Equipment Effectiveness (OEE) is a KPI which reflects overall equipment or machine performance in a single number, expressed in %.

OEE compares the actual ok output to the total output achievable in perfect conditions. As perfect conditions are not likely to be permanently granted, OEE is a mere theoretical benchmark, nevertheless something operational staff should aim for.

Overall mean encompassing  three other key metrics: Availability, Performance and Quality.

  • Availability is the readiness of the machine / equipment to operate when required
  • Performance is the actual run rate compared to the nominal run rate
  • Quality is the number of good parts or quantity right first time compared to the global quantity (good and no good)

Everyone of these metrics is expressed in %, OEE = availability x performance x quality

As OEE is multiplying fractions, the result cannot be greater than the smallest value of Availability, Performance or Quality. That is why OEE is a severe KPI: if one of the intermediate KPI decreases, the OEE decreases faster.

OEE came with Total Productive Maintenance (TPM) and aimed primarily to maximize assets’ yield. OEE was designed to grasp the real performance and not being fooled by tracking assets’ utilization.

By utilization I mean the ratio machine time used / available time. A machine used for production 90% of the available time, seems good. But if this machine runs at 60% of its nominal speed and 15% of its output must be discarded, OEE will be 90% x 60% x 85% = 46 % which is not good at all, as more than half of its productive capacity is wasted.

Demonstrated capacity

The OEE performance is a snapshot of demonstrated capacity, e.g. what the machine / equipment / supplier can really achieve.

The capacity above demonstrated capacity up to nominal maximum capacity is wasted.

It is like a beaker (fig.) having a 100ml capacity but all the leaks limit the real capacity to 60%.

Changeovers are usually a major cause of machine downtime and account as “leaks”. Changeovers duration can be drastically reduced with SMED, thus fixing the leak and recovering some or the wasted capacity.

When breaking down all causes leading to waste of capacity, it soon becomes clear that maintenance issues account only for a (usually small) fraction. OEE therefore gained interest for itself, not only as a KPI within Total Productive Maintenance (TPM).


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The Quick Beginner’s Guide to 5S – Seiso or Sweep, Shine, scrub

Chris HOHMANN

Chris HOHMANN – Author

The third S of the series of 5 stands for Seiso, which can be translated as ‘cleaning’ or for the sake of verbs starting with an S: Shine, Scrub, Sweep, Sanitize and the like.

In the introduction post to this series, I summarized 5S as a philosophy, approach or methodology to provide simple, effective rules for tidiness, maintaining workplace in good, safe condition and fostering a continuous improvement of the standards, rules and discipline.

Good quality as well as safety is easier to ensure in a clean and tidy place. But cleanliness is not only for the good aspect of the place, it is also a helpful to notice damages on machines and equipment such as leaks, breakage and misalignments.

These minor damages, if left unattended, could lead to equipment failure and loss of production and/or quality issues. Regular cleaning is a type of inspection. Seiso is an important part of basic TPM; Total Productive Maintenance

Daily cleaning is an opportunity to assess machines’ condition and to detect the forerunning signs of potential trouble. While sweeping a machine, an operator may notice abnormal heat or uncommon smell, vibrations, leaks or hear unknown sound.

Some early warning signs may remain unnoticed if covered with grease, lubricant or scrap.

In a clean, tidy environment, any abnormal condition is noticed much easier and faster. Again, a leak of lubricant would be noticed immediately on a clean machine, while it would not if the machine was constantly oily.

In the example of this picture, the lubricant was not that easy to see (at least from some distance) on the green paint, I therefore took a white wipe to make it visible.

Fallen-off nuts and bolts from equipment or product get noticed in a clean environment, not in a dirty one.

A clean workplace is also important to quality. I remember my early years as production manager of the French Yamaha Hi-Fi plant, and the care we took to prevent the front face from our high-end CD players or Receiver to get any scratch.

Cleanliness of the workplace, the jigs and even sweeping cloths was crucial to prevent the sensitive surface to be scratched. Would the apparatus later be rejected on inspection for front panel scratch, it had to go through a long costly exchange process.

Seiso is often mistaken as plain cleaning, but there is more about it. Once the machine or the workplace has been cleaned up to a satisfactory, nominal state, the next objective is to work on preventing it to get dirty or degraded again. It is smarter to avoid the need of cleaning / repair than to clean / repair over and over again!

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Related: Just posted: Why 5s’s Scrub & Shine is not (only) about cleaning

Next >Seiketsu or Standardizing


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