Page 276 - How To Implement Lean Manufacturing

Using the Pr escription—Thr ee Case Studies 253

We Start Production
Work started and went exceedingly smooth. Quite frankly, since they had been forced
into doing this, I expected resistance, but surprisingly none occurred—instead, the
whole group was cooperative. With only four pieces at each station, the line filled
quickly and production was moving smoothly at about 40 seconds cycle time. Station 4
was clearly the bottleneck. It was extremely awkward for the operator to transfer her
part to Station 5. The supervisor recognized the problem, had a small sheet metal slide
made, and installed it. By noon, the line was producing at less than takt. In fact, by the end
of the run, the line was producing smoothly and comfortably at a 28-second cycle time
and the 800-unit batch was, for the first time, completed in less than one shift. We had
only one major problem. The materials supply and kanbans were set up to supply at the
older slower rate, so the materials handler had to make many emergency runs to keep
up with the cell. Recall that they had started at the supply end with detailed plans for
every part, so when we improved the cell, all their part plans needed to be redone.

Quick Early Gains Are Huge
In summary, an 800-unit shipment that had previously taken a ten-person cell over two
complete shifts to complete, was now being done in less than one shift with only five
people. Hallelujah! (See Table 16-6.) It does not get much better than this when you deal
in process improvements. All this without any capital expenditures, and no quality or
other downside issues at all! I was pleased. Very pleased.
A large uninteneded consequence resulted from this process improvement. As it
turns out, this controller was one of a family of controllers that were all made on this
work cell. Plus, the new layout could be used for the entire family. The ten-person
cell would normally work 24 hours, 7 days a week to make the demand for the entire
family. Now they could produce the demand in less than four days with only five
operators. The savings was a net reduction of 30 man days of work per day, forever.

No “Lean Hero of the Month” Here
Wow, think about this. The GM was so proud of his reduction of materials handlers by
nine persons, I figured I would be hailed as the Lean hero of the month. Instead, every-
one just yawned and didn’t even say “thanks.” In fact, the lead industrial engineer, who
resisted the suggested improvements in the first place, now said, “We had planned on
doing that all along.” So I guess my entry into the “Lean Hero of the Month Club”
would have to wait a while. But the cell was certainly setting new performance stan-
dards and was ready for a new time study, and also ready to be rebalanced to achieve
further gains.

Metric Original Case Leaned Process % Improvement
First piece Lead 4.5 hrs 9 min. 97% reduction
Time
Batch Lead Time 20 hrs 8.5 hrs 58% reduction
Space utilization 425 sq. ft. 160 sq. ft. 62% reduction
Operators per cell 10 5 50% reduction
Labor costs/unit 15 min/unit 3.19 min/unit 79% reduction
TABLE 16-6 Gains Summary, Zeta Cell