Page 60 - TPM A Route to World-Class Performance

The top-down and bottom-up realities of TPM 41

Outside services
Maintenance olhead

set-up & adjust

Difficult to High impact
measure on profit

Fipre 3.14 True cost I$ manufacturing: seven-eighths hidden

good without the other. Fortunately, the measurement of cost/benefit and
value for money are central to the TPM philosophy.
In most manufacturing and process environments these indirect or lost
opportunity costs include the following, which we call the six big losses:
Breakdowns and unplanned plant shutdown losses
Excessive set-ups, changeovers and adjustments (because ‘we are not
organized’)
Idling and minor stoppages (not breakdowns, but requiring the attention
of the operator)
Running at reduced speed (because the equipment ’is not quite right’)
Start-up losses (due to breakdowns and minor stoppages before the
process stabilizes)
Quality defects, scrap and rework (because the equipment ‘is not quite
right‘)

In Figure 3.15, we show the six big losses and how they impact on equipment
effectiveness. The first two categories affect availability; the second two affect
performance rate when running; and the final two affect the quality rate of
the product. What is certain is that all six losses act against the achievement
of a high overall equipment effectiveness.
In promoting the TPM equipment improvement activities you need to
establish the OEE as the measure of improvement. The OEE formula is simple
but effective:
OEE = availability x performance rate x quality rate