Page 191 - How To Implement Lean Manufacturing

Sustaining the Gains 169

display the average cycle time. It told what the average was, how many units were
produced with that average, and when the averaging had started. We retrofitted the
station with a reset button and—voilà!—we had an excellent piece of transparency.
Ultimately, after a few kaizen events, we were able to achieve cycle times of 4.6 seconds,
consistently. Furthermore, now the operator, supervisor, and anyone interested could
look at the display and see how the process was performing. Literally, we could find the
instantaneous production rate. This was an imaginative solution that added signifi-
cantly to the transparency of the system.
However, remember that availability losses were about 10 percent. The OEE infor-
mation was valuable in helping us understand the losses, but not very helpful in solv-
ing many of the problems due to the lagging nature of the information. Nonetheless, we
were able to reduce some losses. Check sheet information logs on white boards were
installed on the andons to gather information at the time the andon was activated. This
helped distill the information further and made it available for future use. We now had
a recording function for the andons. However, the review of the OEE information
showed that 90 percent of the availability losses were due to machine adjustments. A
quick review showed that most adjustments could not be explained and were just
apparently “tinkering” by well-meaning technicians. We did some training, clarified
some work procedures, and these availability losses immediately dropped like a rock—
as did the workload of the technicians. They were not comfortable with this at all, how-
ever, since they were highly motivated, very energetic and weren’t used to having any
spare time.
It might be asked how we ever met the hourly goal of 600 units when the process
cycle time would not support it and our average production was only 433 units per
hour? Well, the answer is both simple and revealing.
The simple part is this. The way production was measured was to count the produc-
tion of trays that each held 120 units and multiply by the number of trays. No partial trays
were counted. So, production was in multiples of 120. A tray of 120 units was the trans-
fer batch. Also, since the line leaders knew that the managers wanted the production
goal to be met, it was better to meet the goal some of the time than none of the time.
Consequently, at the top of the hour when production was counted, if a tray was nearly
filled, the line leader might wait to enter the data. Of course, the next hour the produc-
tion was even shorter than it would have been if the data had been reported accurately.
This 120-unit transfer batch created some problems beyond accounting for production,
so we later cut the transfer batch size to 48 units. This not only helped the accounting
but reduced the processing lead time, as you might expect.
So how is this so revealing? It was a symptom of the entire facility. Everyone
wanted to do well and be seen doing well. As I said earlier, they were a motivated
group. And this motivation served us well as we implemented other process changes
and improvements.
We could go on, but let’s briefly review what we just discussed.
• First, our production system improved. The production rate increased by
42 percent with virtually no invested capital.
• Second, once the improvements had been made, we could now “see” the system
status, and if there were problems, we could rapidly find and implement the
needed countermeasures. We now had the information to do Rapid Response
PDCA. Our system transparency had improved immensely, allowing our
problem solving to improve immensely, too.