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Cellular Manufacturing 205

manually advanced. The conveyor track would not fit in the U cell as designed.
We either needed to enlarge the size of the cell or change its shape. We immedi-
ately converted this cell to an L-shaped cell and Sunday night tested it. It worked
just fine.
Monday morning came and we trained the operators assigned to our new cell,
arranged for a new materials handler and by morning break we had the cell in pro-
duction, although nowhere near the design cycle time. Materials delivery was a prob-
lem, but that was quickly ironed out. By the end of the shift, the bugs had been worked
out and the cell was producing, with no quality losses, at a 55-second cycle time.
Although we had hoped for 45 seconds, we were still pleased. The workers were
pleased as well. They responded extremely well to the longer cycle times. They sim-
ply said that they felt more comfortable and it wasn’t as stressful. The looks on their
faces were unmistakable—they were grateful. We made some minor changes and pre-
pared for the next day.
Tuesday was a better day. Many of the efficiencies we had hoped for were real-
ized. The cell increased in speed and the cycle times for each station had improved
per Table 13-3.
We were really pleased, but let me tell you: Greg was ecstatic. Not only was our
experiment clearly showing success, but for the first time in a very long time the shop
steward visited him with good news. The steward had gotten unsolicited comments
from the cell operators. Uniformly, they liked the new cellular arrangement. They par-
ticularly liked the longer cycle times. Their stress was reduced significantly since they
could now advance the unit when their work was done. They no longer had to worry
about the conveyor taking their work away before they were ready.
We spent the rest of that week using only one cell while we planned for installa-
tion of the other three cells. Meanwhile, the original line was in operation as usual.
The cell gave the line added production and this gave the plant a chance to catch up
on production. While this was underway, each day we would rotate a new crew into
the L cell, and after a little training they would begin production. By the end of the
week, nearly all operators had been trained on the new work layout. It was received
very well.
Over the weekend, we dismantled much of the old line and constructed the three
additional cells, per Fig. 13-2. The construction was simple and did not take long except
for the raw materials supply which needed to be arranged for each cell. On Monday
morning we started up and there were a few problems, but by the end of the third day
the cells were stable and producing at a record rate with all four L cells producing. We
completed a time study and the new cycle time was 12.5 seconds.

Work Station A B C D
Design—Original Work, Secs 46 39 44 43
Design—Trans Time, Secs 2 2 2 2
Design—Total, Secs 48 41 46 45
Current Cycle Time, Including 45 40 44 42
Transportation Time

TABLE 13-3 Cycle Times for Work Stations, Cellular Design