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Figure 4.1 Relationship between five pillars (Nakajima) and three-cycle TPM improvement plan

Goal:

economic world domination via:

- flexibility

- right products

- right time

- right quality

- right price

Trouble-free:

zero defects zero equipment failures zero accidents

Stockless:

no buffer stocks no WIP

All equals:

total waste elimination

TPM viewed as an essential pillar for equipment reliability and product repeatability through people and not the systems alone

Figure 4.2 Essence of Japanese TPM

Total Productive Maintenance (TPM) combines the conventional practice of preventive maintenance with the concept of total employee involvement. The result is an innovative system for equipment maintenance that optimizes effectiveness, eliminates breakdowns and promotes autonomous operator maintenance through day-to-day activities. Specifically, TPM aims at:

1 Establishing a company structure that will maximize production system effectiveness.

2 Putting together a practical shopfloor system to prevent losses before they occur, throughout the entire production system's life cycle, with a view to achieving zero accidents, zero defects and zero breakdowns.

3 Involving all departments, including production, development, sales and management.

4 Involving every single employee, from top management to front-line workers.

5 Achieving zero losses through small-group activities.

Figure 4.3 What is TPM? The JIPM definition

The scope for improving on the way we do things now can only be established by adopting the continuous improvement approach and by never accepting that what we are achieving today will be good enough for the future. A striking example of this comes from a visit by the authors some years ago to the press shop in a Toyota automobile plant in Japan, where it was observed that a 1500-tonne press die change took place in the astonishingly short time of 6}/2 minutes. When this was commented on, the reply came: 'Yes, yes, we know, we need to reduce the time to 5 minutes.' At that time, a comparable change in a UK plant could take up to 4 hours. Straightforward die change is regularly achieved in a single minute!

Analogies and visual aids are essential components in the process of introducing TPM. One of these is the concept of healthy equipment, as already illustrated in Figure 3.12, which portrays the 'apple a day' for good health, the 'thermometer' to monitor well-being and the 'injection' to protect against disease. Routine asset care involving lubricating, cleaning, adjusting and inspecting ensures that the plant is protected against deterioration and that small warning signs are acted upon. Condition monitoring and prediction of impending trouble ensure that developing minor faults are never allowed to deteriorate to a breakdown or a reduced level of machine effectiveness. Finally, timely preventive maintenance safeguards against the losses which can come from breakdowns or unplanned stoppages. These messages are most effective when expressed in terms which hook into local and, hence, specific vision and values.

A key benefit of TPM, and an important strength of Japanese management, is the use of structured roles and responsibilities, which reduce both complexity and uncertainty. In reality, there is only one TPM. It is a package of integrated principles which are greater together than the sum of their individual parts. As companies improve, TPM has been adapted so that it continues to represent manufacturing's best practice. The original five principles remain at the core of the wider-reaching company-wide TPM discussed later in this chapter.

There are difficulties in implementing TPM in every country, including Japan. As this is the country with the most experience, the TPM implementation process is at its most mature in Japan. Naturally, this is an evolving situation as more non-Japanese companies achieve 'world-class' TPM applications. The three-cycle TPM improvement plan was developed to deal with the need to:

• progressively build management commitment and consensus based on results;

• build on existing good working practices;

• produce rapid results;

• get buy-in to new ideas across international boundaries.

Within the rigour of the three-cycle, nine-step process, it provides the flexibility to build on strengths and reduce weaknesses. In this way, it builds on the principles rather than diluting their undoubted synergy.

Let us now take a closer look at each of the five Nakajima TPM principles, together with the measurement, condition and problem prevention of the TPM improvement plan (Figure 4.1).

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