This article: Introduction Total Productive Maintenance
|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.
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.
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.’
TPM: Popular in the (semi-) processing industry, in food production and among automotive suppliers
Examples of companies that apply TPM:
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.
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
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.
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.’
'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.’
^ With TPM, small but multidisciplinary teams gradually improve the Overall Equipment
Effectiveness of their machines or production lines, by way of 'small group activities'.
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.'
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.
‘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.’
> For an introductory TPM-case see Purac below!
Total Productive Maintenance: the jargon
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).
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.
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.
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.’
^ To make hidden losses visible, often a Total Clean Out is necessary (photo Purac)
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.’
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’
Total Clean Out
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.’