Page 83 - Toyota Under Fire

TOYOT A UNDER FIRE

of the unique American cars that they produced (global cars like
Corolla and Camry were still shared with Japan). That meant that the
North American plants had to be able to manage complexity while
maintaining quality as well as their Japanese counterparts did.
Jobs on a Toyota assembly line have been standardized since
the days of Ohno. Each worker knows exactly what to do and
how much time he has to do it (the line speed is known as the
takt time, or just takt, and is based on the rate of customer de-
mand). However, if the line speed changes to a new takt to ac-
commodate a change in demand, the number of workers on the
line will need to be adjusted up or down, with each worker tak-
ing on fewer or more tasks. Though it may seem counterintui-
tive, slowing down the assembly line (a longer takt) is a harder
change than speeding it up. A faster line can usually be accom-
modated by adding workers and giving each worker a few less
tasks to do. Thus, it’s only the additional workers who need to
be trained when the line speeds up. A slower line means taking
workers off the line and allocating their tasks to other workers, so
every worker has new tasks to do to fill up a longer cycle of work.
In this case, each worker has to learn standardized work for a new
job (and some of the standardized work will need to be changed).
The more often the speed of the line changes, the harder it is for
workers to maintain their standards of quality and productivity.
TMMK, the original Toyota plant in the United States, had
been operating for more than 20 years when the recession hit. With
the buffer provided by the Japanese plants, TMMK had rarely
had to change takt, and the vast majority of the changes that had
been made had been to increase the line speed. The plant had got-
ten better and had had more frequent takt changes in the years
leading up to the recession, but it still made these changes much
more slowly than in Japan, and the changes were still rare events.

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