The Pursuit of Excellence
A Manager's Guide to Quality
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Specifications Revisited
|
Summary
| |
Total Assembled |
Acceptable |
Ideal |
Too Loose |
| Attempt 1 |
1136 |
864 |
409 |
136 |
| Attempt 2 |
1205 |
904 |
422 |
96 |
| Attempt 3 |
1316 |
934 |
434 |
66 |
| Attempt 4 |
1471 |
956 |
427 |
44 |
| Attempt 5 |
1693 |
966 |
406 |
34 |
| Attempt 6 |
2001 |
980 |
381 |
20 |
| Reduced variation |
1031 |
998 |
618 |
2 |
When we accepted that the amount of variation in the shafts and bearings
was inevitable, and simply tried to find a way to match the output of our
processes to the specifications, we found it was impossible. Even to
achieve a high proportion of conforming product meant that the number
of operations required to produce each assembly went up dramatically.
By concentrating not on the specifications but on the processes themselves,
it is possible to find the true limits of the process, and to keep it
performing at its best. That means on target, and with minimum variation.
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