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This article: Introduction Total Productive Maintenance
Source: Business-improvement.eu
TPM: The smooth organization

^ For more articles about TPM, use the drop down menu in the top left corner. This is the introduction article

Introduction Total Productive Maintenance
Total Productive Maintenance (TPM) is a business process improvement method, developed from the perspective of maintenance management. TPM concentrates on productivity improvement, primarily by way of maximizing the availability of equipment.
To do that, small multidisciplinary teams improve step-by-step the Overall Equipment Effectiveness (OEE) of their machines or production lines. TPM was first applied by the Japanese company Nippondenso, a supplier to the automotive industry. Later the method was further developed by the Japan Institute for Plant Maintenance. In the European Union, Unilever is one of the biggest propagandists of TPM. This food multinational has used this improvement method for over 15  years, during which it has grown into an overarching process management system. The Finnish company Outokumpu, among many others, adopted a similar approach.

The smooth organization
Total Productive Maintenance is a suitable method if there is complex (and/or expensive) machinery of which the capacity is insufficient, or if the maintenance costs of those machines are racing up.
Like many other process improvement methods, TPM has grown into a general process management method which can be applied in many situations, even if logistic or human factors should be accounted for. TPM emphasises the importance of creating a feeling of ‘ownership’ on the shop floor. Therefore, this approach is often associated with strong involvement of the employees. This makes TPM very useful as a starting point for a World Class programme, with the possibility to add Lean and Six Sigma tools later. This is also the reason why the acronym TPM is more and more redefined as Total Productive (of Productivity) Management.


TPM is often positioned as a prerequisite voor Lean manufacturing. The reason: When you machinery isn't functioning reliable and thus predictable, it is simply not possible to produce just-in-time with little stock between the production steps. Especially when there are factories that have to exchange materials in a network, it is common to apply TPM in the individual factories first, and then add a Lean-program to stimulate the flow in the supply chain.


Total Productive Maintenance
 (introduction article)
Jointly improving the machine efficiency, step-by-step
By Dr Jaap van Ede, business-journalist, founder business-improvement.eu.
The first version of this article was published in the dutch specialist journal PT Industrieel Management. Since then, the article was regularly updated.


The foundation for an efficient factory is smooth running machinery. Therefore everyone – from operator to maintenance engineer – should make joint efforts to improve the Overall Equipment Effectiveness (OEE). This philosophy is the heart of Total Productive Maintenance (TPM). Small multidisciplinary teams, who ‘own’ machines or production lines, improve the OEE thereof, step-by-step.   
To give the program focus, attention is given to management ‘pillars’ like autonomous maintenance, preventive maintenance, training, security and standardization of working methods. The ultimate goal: zero errors, zero work-related accidents, and zero losses!

All efficiency improvement methods aim to improve productivity and reduce losses, says the Dutch TPM-consultant Ton van Kollenburg. 'Besides that, all methods share a cyclical plan-do-check-act approach

'I think it is typically Western, that different business disciplines have developed their own line of approach. In Japan, there is less parochialism. Only here, you see a strict separation between for example Lean manufacturing and the Theory of Constraints, both developed from a logistic perspective, and Six Sigma, which was invented by quality managers.’

Also maintenance technicians developed their own view on improvement. Their most important tools are Reliability Centered Maintenance and Total Productive Maintenance, as discussed in this article.

TPM team-meeting at Hitachi (Japan)TPM: Popular in the (semi-) processing industry, in food production and among automotive suppliers

Examples of companies that apply TPM:
  • Delicia
  • Heineken
  • Lassie
  • Nedalco
  • Solvay (with TPM as a stepping stone for WCM)
  • Unilever (with TPM as a stepping stone for WCM)
  • Outokumpu
The field of application of TPM is wide. This is illustrated nicely by applications in Japan. There you find TPM-implementations in food and chemical industry, metal industry, the automotive sector and in machine factories.


Shared responsibility
Nearly all industrial production processes are carried out with the aid of machines. So it doesn’t sound bad at all to focus on the machinery, if you want to increase the productivity. The basic principle of Total Productive Maintenance (TPM) is, that everyone should start to feel responsible for maintenance. Note, that this also encompasses ‘improvement’ of the machinery. According to the TPM-philosophy, a machine functions worst at the moment it was bought. After that, the goal is to find and eliminate hidden defects. That is the basis for continuous improvement!

TPM is a Japanese method. However, the story of TPM begins in America, where concepts for preventive maintenance were already developed in the forties, among others as part of the Training Within Industry (TWI) program.

TWI was developed during WOII in American factories. The goal was to quickly train new workers, as a replacement for employees who had left as soldiers. TWI introduced for the first time a scientific approach to process improvement. Today, this approach is known as PDCA, or plan-do-check-act, and it became deepley embedded in the Lean approach of Toyota.

Hein Winkelaar1, TPM-manager at PURAC Biochem, thinks this history of preventive maintenance is the reason why Americans nowadays find it sometimes difficult to accept TPM. ‘The Japanese assume a shared striving for improvement in small steps, which they call Kaizen. They say that mapping what has to be improved comes first, next everyone should try to prevent problems themselves. This problem-preventing attitude and shared responsibility is what they call autonomous maintenance. Implementing a formal preventive maintenance programme is considered as the next step. Americans don’t agree. They say that everything starts with preventive maintenance.’

Total employee participation
In the beginning of the sixties, several Japanese companies studied the preventive maintenance methods in the US. That lead to the establishment of the Japanese Institute for Plant Maintenance (JIPM).

The phrase TPM came up for the first time in 1961, inside the Japanese company Nippondenso. At that moment, this supplier to the automotive industry carried out a project named  'productive maintenance with total employee participation.'

Seiichi Nakajima, employed within the Japan Institite of Plant Maintenance (JIPM), worked out the TPM-ideas in a scientific way. Among others, he developed a phased implementation process, originating from eight management pillars. The first three of these are striving for continuous improvement and introducing autonomous and preventive maintenance. 

Raising consciousness
'The implementation of TPM starts with raising the consciousness of hidden losses’, explains Van Kollenburg. ‘One example is a machine failure, or time needed for a machine set-up. Also if a machine cannot run at full speed, or if it delivers inferior products this is considered as a loss-making activity.’
 
In a ‘loss-free’ process, the overall equipment effectiveness (OEE) of all machines equals 100%. In that case every machine always operates at full speed and delivers only products of good quality (see also the box: TPM-jargon).

In reality, the OEE often only is 40-50%. It is the goal of TPM to raise the OEE gradually, per machine, to at least 80%. ‘We start with a pilot-project, in which we measure the OEE of one particular machine. First, we do this simply with pen and paper. This has the advantage that all people concerned will get a feeling for the things that are influencing the OEE.’

Continuous improvement
At the same time, overdue maintenance is carried out. This is part of tidying the work floor, which is called a Total Clean Out. This, followed by the formal implementation of 5S clears the way for implementing the first pillar of TPM: continuous improvement.

'At that moment the first small and multidisciplinary team is formed, which starts to tackle one specific problem that limits the OEE. The project they carry out is called a small group activity or SGA. In a SGA-team usually there are both machine operators and mechanics, and besides that for example quality inspectors and/or logistic managers. The advantage is that the whole group starts to feel responsible for ‘their’ machine or production line.’

Teamwork within the Dutch company Purac
^ With TPM, small but multidisciplinary teams gradually improve the Overall Equipment
   Effectiveness of their machines or production lines, by way of 'small group activities'.
   (photo Purac)


Owner
The team becomes owner of the performance of their machines. This results in a cultural shift. For example “I operate, you repair”, is replaced by “We, as operator and engineer, share the responsibility for keeping our installation working”

Problems, to be dealt with by the SGA-team, are selected by way of a Pareto-analysis. Then, the team will search for the root cause of the problem. An Ishikawa-diagramme, to map causes and consequences in a fishbone structure, can be helpful. Sometimes the more extended CEDAC-method is used as well, this acronym stands for Cause Effect Diagram with Additional Cards.

'When the SGA-team has detected a root cause of a problem, they will send a proposal for a resolution to their senior management. Included is a cost-benefit analysis. If the solution is approved, it will be implemented. Finally, if will be checked if the OEE is improved.'

Step-by-step
After that, the SGA-team continuous by attacking the next problem, that then limits the OEE the most. This way, the OEE is improved step-by-step.

This endlessly repeated improvement cycle is however only the first step of TPM. When that ‘pillar’ is implemented, seven more management pillars should follow. ‘Pillar number two concerns the introduction of autonomous maintenance. After that, maintenance is not only a task for technicians, but involves everyone, between the bounds of their expertise. For example, operators should inspect their machines regularly, and they can sometimes clean and/or lubricate their equipment themselves.

Pillar three refers to making a schedule for preventive (and sometimes also predictive) maintenance. Pillar four entails a training programme, to make all employees familiar with the TPM-principles and continuous improvement, not only in general bit also in relation to their own place of work.

The fifth pillar, early management, deals with the development of new production processes and/or the purchase of new machines. In the latter case, during the selection process, the amount and method of maintenance are already taken into consideration.

‘I saw once that a new machine was installed with the door facing the wall. To prevent such things, early management is important.  Sometimes it can for example be handy if a machine has transparent panels, this simplifies the carrying out of inspection rounds.’

Pillars
Van Kollenburg thinks that the first four or five TPM-pillars are the most important. ‘However, I am not so charmed by thinking in pillars. I think that is one of the weakest points of TPM. The borders between the pillars are vague. Essentially, TPM should form a whole. Then it is for example possible that a SGA improvement-team discovers that it is necessary to raise the frequency of preventive maintenance.’

‘Companies with a lot of machines and or complex process control systems cannot leave out TPM’, Van Kollenburg concludes. ‘However, it is important to prevent local optimization. Therefore I advise to supplement TPM with a logistic improvement method like Lean manufacturing.’

Focus
To give the process improvement with TPM focus, strategy defining methods like Hoshin Kanri are often applied, for example by Heineken. First, it is then determined which losses should be reduced in a factory during the next year. Next, these priorities are translated into Key Performance Indicators (KPI's), first for the middle management level, and later for the operational level. This way, you get a cascade of KPI's. The idea is that finally, everybody knows how he or she can personally contribute to fulfill the improvement agenda!

>  For an introductory TPM-case see Purac below!

Total Productive Maintenance: the jargon

5S
This refers to the five Japanese words seiri, seiton, seison, seiketsu, shitsuke. These represent guidelines to organize and manage the workspace in such a way, that a visual controlled and efficient production becomes possible. The key target of 5S is to keep the workplaces clean and organized.


Dojo

Strictly speaking this is a sports centre for Japanese martial arts!. Within the framework of TPM, a Dojo is however an internal training facility to practise this improvement method.


First time right

This expression emphasizes the importance of doing things correct the first time. After all, rework will reduce the Overall Equipment Effectiveness!


Gemba

Gemba is a Japanese term for ‘place where it happens’, here this is the manufacturing floor. The saying “go to the gemba" means that managers should visit their shopfloor frequently to discover problems and to help to realize improvements (go and see).


Kaizen

Literally this means adjusting a process (kai) to become good (zen). However, Kaizen also stands for implementing small improvements, step-by-step. See also: SGA.


Labeling

Labeling involves the marking of things that are desired or not. Labeling methods vary from cards with desired repair-actions and target dates on it, to marking the correct position of a temperature indicator.


Model machine

During the implementation of TPM, this machine is ahead of the other equipment regarding optimization and standardization (by rolling out the TPM pillars)


Overall Equipment Effectiveness (OEE)

This index number for the machine efficiency is multiplication of several sub-indicators, which all have a value between 0 and 1, and 100%. Usually, at least the following sub-indicators are included in the OEE: 

  • The machine availability A = (scheduled production time – standstill)/( scheduled production time)
  • The relative machine performance P = (average processing time)/(fastest possible processing time)
  • The Quality Q = the fraction approved products

In that case,  OEE = A x P x Q x 100%.

It is possible to add extra sub-indices at will, such as the supply performance S. By doing that, the definition of the OEE can be stretched  to such an extent, that it is better to rename it to Overall Factory Efficiency (OFE).
In all cases, the aim of carrying out OEE-measurements is the detection of hidden losses. This resembles the elimination of waste with Value Stream Mapping, a tool used in Lean manufacturing.


One Point Lesson (OPL)
This is a best practise operation procedure written down on a sheet of A4, for example simple (visual) instructions to set-up, inspect and/or maintain certain machines. The aim is to standardize operating procedures, as a foundation for improvement.
One Point Lessons are also used to describe suggestions for improvements, which are then (before implementation) subject to discussion and possible adaptation by all the people involved.

Pareto
This is the concept that 20% of the causes are usually responsible for 80% of the consequences (like machine-failures resulting in a low OEE)


Pillar
The goal of the management pillars is to improve low OEE-values in a targeted way. TPM embraces at least eight management pillars, or areas of special interest. These are:

  1. Continuous (focused) improvement - kobetsu kaizen
  2. Autonomous maintenance - jishu hozen ('maintenance is a task of everyone’)
  3. Planned (preventive) maintenance
  4. Training (with the aim to standardize the work)
  5. Early (equipment) management: maintenance is taken into consideration when new equipment is purchased. Another aim can be the optimal design of a new production line, so that it intrinsically has a high OEE.
  6. Quality management
  7. TPM in the office: the optimization of administrative processes.
  8. Safety and environment

Sometimes ‘the optimal use of employee competences’ is added as ninth pillar. Another rather popular extra pillar is Lean Flow, to introduce Lean manufacturing tools and to prevent local optimization.


SGA or Small Group Activity

A multi-disciplinary improvement group, with for example engineers, operators and quality inspectors, tries to solve one specific problem that is responsible for a low OEE-value.


SMED

This acronym stands for Single Minute Exchange of Dies. SMED was invented by Shigeo Shingo at Toyota. He claimed that molds for forming automobile bodies should be exchangeable within ten minutes. Later, this concept widened to reduce machine set-up times in general. In TPM the aim is to increase the OEE, by reducing the standstill time. SMED is also applied in Lean manufacturing and QRM, then with the goal to reduce waiting times.


TPM-board

This is a board with the size of a poster, with OEE-charts, objectives, activities and the members of a SGA-team. These boards typically hang in places where many people come, for example in coffee rooms.  




Case: Purac

Total Productive Management improves all business processes.

Within Purac, a company which makes lactic acid derivates, TPM is not ‘limited’ to Total Productive Maintenance. The idea is not only to optimize the manufacturing activities, the goal is to improve all business processes!. To stress that, the employees speak of Total Productivity Management.

Hein Winkelaar1 is TPM manager at PURAC in the Netherlands. ‘CSM, our parent-company, acquired a factory from Unilever which produced bakery ingredients . The management of CSM was astounded how much the employees of that plant knew about TPM. Therefore they decided to implement that method within the whole CSM group. That way, TPM was introduced in our factory too, this happened three years ago’, Winkelaar explains.

'I am the project manager for the rollout within Purac’, he adds. ‘However, it is the intention that my job will become superfluous in time. It is typical for TPM that in the end, responsibilities are handed over to the people on the shopfloor.’

The implementation of TPM is guided by the Japan Maintenance Associate Consultants (JMAC) in Paris. 'This is the European branch of JIPM, the Japan Institute for Plant Maintenance. JMAC also cooperates with Unilever, this explains why we choose for their participation'

'We follow strictly the rules of the Japan Institute of Plant Maintenance. So, the implementation is done pillar-by-pillar. There are more then hundred steps, but we do not experience that as bureaucratic. On the contrary, TPM stimulates solution-oriented thinking. By way of the TPM-boards with OEE-charts, our people see the actual problems and start thinking about possible solutions.’

Total Clean Out within Purac       
^ To make hidden losses visible, often a Total Clean Out is necessary (photo Purac)


Although TPM seems complicated, in practise this not the case. 'The necessity to implement all the TPM pillars is a logical consequence of the first pillar, continuous improvement by searching for and eliminating losses.'

Winkelaar clarifies this, by a description of the pilot project for TPM within Purac. This was done in a factory that produces calcium lactate powder. ‘We started to define OEE-indexes for all the machines in that plant. Next, we did a Pareto-analysis to map which things were limiting the OEE-indices the most. That turned out to be two things. First, a pump which started to leak every three weeks. And second, a communication problem between two departments.’

Human actions
The latter issue requires an explanation, because OEE-indexes in general only include sub-indices that concern the machine efficiency, such as the availability, performance and product quality. ‘This is true. But if you do that, you pass by the fact that 80% of the efficiency losses are caused by human actions. Therefore we sometimes include as many as ten sub-indices in our OEE-calculations. For example we take into account if raw materials are supplied in time. In addition, timely transportation form one factory to another can be included. This brang the afore-mentioned communication problem to light.’

An improvement group was formed to solve the problem. ‘In that team were two people from each factory, and besides that a mechanic and a quality manager. The good thing about TPM is, that such a team often finds a solution by themselves in 70% of the cases. Here, the solution turned out to be, that the factories should communicate about their status by e-mail. In addition, the responsibilities of the departments were laid down in separate OEE sub-indices. The supplying department now has its own index. So, it is plain when they do not meet what is promised.’

In a similar way the other issue was resolved, the frequent occurring of pump leakages. ‘In that improvement team, someone from the pump supplier was included. It became clear soon, that a suboptimal packing was used, and that there weren’t timely inspections for leakages. So, pillar one, focused improvement, in this case automatically lead to pillar three: preventive maintenance’
 
Continuous improvement is a cyclical process, adds Winkelaar. 'When we had solved the biggest problems in the powder factory, we continued with the problem that was at that moment limiting the OEE the most. That turned out to be a packaging line, where about 2,5% of the packaged products were rejected, caused by contamination. Dirty sensors turned out to be unable to detect the packages. In addition, conveyer belts sometimes made black stripes on them.

Total Clean Out
The solution: a Total Clean Out.  'To stick to the improvement, we enrolled pillar two of TPM, autonomous maintenance. From that moment on, operators cleaned their machines themselves. To make that possible, racks with tools were placed in their neighbourhood.’
 
Winkelaar returns to the problem with the leaking pump, to give another example which clarifies the relation between the TPM-pillars. ‘If you standardize the start-up procedure, the pump is overloaded less often. As a consequence the frequency of preventive maintenance can be reduced.’

The experience that is gained by applying the first four pillars, becomes of use when pillar five is brought to bear: Early management. The goal of that is to take maintenance into consideration when new equipment is purchased.

The first two pillars of TPM are now fully implemented within Purac. ‘Last  year TPM saved us as much as one million Euro. We are making more products with the same production capacity, and our maintenance costs have dropped.’

The final goal is to compete for the yearly awards of the Japan Institute for Productive Maintenance. 'In that way, we can show our customers and shareholders that we are becoming a world class manufacturer.’

1) Hein Winkelaar has left Purac and started a business of his own.



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