5, 1998 Design News
Emerging trends in manufacturing
Larry Maloney Editorial Director
Smyrna, TN--While the United Auto Workers
dueled General Motors this past summer, a fresh report
surfaced showing that U.S. firms still lag Japanese
car companies when it comes to factory productivity
in North America.
The new research, released by Harbour and Associates
(Troy, MI), found that Nissan's Smyrna, TN, plant took
the fewest hours to assemble a vehicle--just 16.55 for
the Altima and Sentra compact models. The plant also
builds the Frontier small pickup--and led in that category
as well, with 18.27 hours required to assemble the average
vehicle. In comparison, the closest U.S. competitor
in the compact car category was Ford's Kansas City plant,
which takes 22.53 hours per car on the Contour and Mystique.
In small trucks, Ford Twin Cities was the closest U.S.
plant to Nissan, at 21.80 hours for the Ranger.
In company averages for hours needed to build a vehicle,
Nissan also led the pack at 17.07 hours, followed by
Toyota (21.31 hours), Honda (22.31 hours), Ford (22.85
hours), GM (30.32 hours), and Chrysler (32.15 hours).
The Harbour organization believes that hours per vehicle
is the best standard for labor productivity because
it captures additional performance factors, including
What's Nissan's secret? In an interview with Design
News, Manufacturing VP Dan Gaudette cited
three major reasons: a high degree of automation, a
focus on design simplicity, and a motivated work force
who play an active role in planning how a vehicle should
Nissan maintains an army of some 600 robots at Smyrna
on chores ranging from painting and welding to materials
handling and parts installation. For example, five robots
handle virtually the entire rear assembly on the Altima.
Extensive use of scanners and bar code readers also
ensures that parts and modules get assigned to the right
vehicles. At the other extreme of automation, Smyrna
relies heavily on a system of people movers--aka "Line-side
limos"--that reduce worker fatigue, cut down on
waiting time, and speed production.
Gaudette says that Nissan strongly encourages design
for assembly among its supplier base. "A major
goal is to achieve simplicity in design. We build three
models at Smyrna, but they can share many of the same
parts." He notes, for example, that the models
once required some 30 different wiring harnesses. Now
it's down to 3 or 4. Interior color options also have
been reduced, and suppliers do more design and assembly
work in instrument panels.
The Smyrna facility is more complex than most plants,
with stamping, body lines, paint shop, and trim and
chassis operations. Yet Nissan wants workers to learn
a variety of tasks. "We do a lot of rotation in
our shops," says Gaudette, "both for ergonomic
reasons and to break up the day. It's very common for
people to do four different jobs in the same day."
The result of all this is that Nissan Smyrna manages
to build a car every 30 seconds. What's more, precious
little time and space is given to "fix-up"
chores. "We believe in building them right the
first time," says Gaudette.
Workers are already involved in helping management
plan the build sequence for a new sport utility vehicle
soon to be assembled at Smyrna. Meanwhile, Nissan engineers
at design studios in Detroit, California, and Japan
are doing computer modeling to preview the assembly
process and insure proper fit and finish for the new
vehicle before actual production.
Says Gaudette: "We have an excellent record, but
manufacturing productivity comes down to striving for
continuous improvement. We take a fresh look at what
we do every year."