Once upon a time in the automotive industry, every plant had its own way of
doing things. Lines were laid out according to what seemed best for a particular
product; equipment was modified and customized to execute tightly circumscribed
tasks. Neither flexibility nor standardization were high on the priority list.
Then competition heated up, capital investment budgets shrank, and automakers
concluded they had to have the flexibility to build several different models
on the same line in order to survive and thrive. To achieve flexibility on a
budget, engineers embraced the kind of wholesale standardization of equipment
that they might have sneered at just a few years earlier. Now the benefits of
standardization seem so self-evident that it is hard to find anyone who will
mount a spirited defense of custom tooling. Once I standardize, I know
exactly what to expect the next time I install a line, explains Jeanne
Geary, executive engineer at Fords Powertrain Operations, I dont
have to waste time trying to predict what will happen in a new situation.
Add to that the fact that the economies of scale that result from buying high
volumes of the same machines can save 10 to 15% on capital investment, and its
not surprising that, according to Ted Brown, vice president of business development
for equipment integrator Johan A. Krause Inc. (Auburn Hills, MI), Everyone
is heading toward greater equipment standardization; theyre just moving
at different paces.
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Ford may know more about standardizing engine assembly equipment than any other automaker. Its carbon copy plants utilize the same machines regardless of where in the world they are located. This one happens to be in Windsor, Ontario.
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How Standard Can You Be? That being the case, is there now or will there soon
be one standard piece of off-the-shelf equipment automakers can quickly plug
in and ramp up? Not right now, says Brown, who adds, But there
are elements of standardization that have gotten us a lot closer in the last
few years. He cites his companys work with Ford on standardizing
engine and transmission facilities as an example of how far the process has
come. Ford is arguably the most aggressive proponent of standardization of powertrain
assembly lines in the industry. Its strategy calls for plants to essentially
be carbon copies of each other: same layout, same processes, same equipment.
We try to develop tooling such that we dont care if a line is running
a four-cylinder, six cylinder or V-8 engine, says Brown. We want
to take out all of those elements that would traditionally drive us toward dedicated
machines and isolate the end tooling as the only truly dedicated tooling.
Much of that can be accomplished today. Electrical panels, human machine interface
(HMI) design, guarding, cabling, conveyors and pallets can easily be made common
across many lines. Components like cylinders and valves now adhere to a common
standard that allows equipment makers to design common mounting fixtures and
replace parts based on price and availability, not a suppliers proprietary
design. And even robot programming software, while not entirely interchangeable,
has adopted enough similar user-friendly programming features that a de facto
standard exists. Beyond that, suppliers are sometimes willing to commonize more
sophisticated components with their competitorsfor an important enough
customer. For example, when Toyota Motor Manufacturing Kentucky (TMMK) installed
its Global Body Line (itself part of a new worldwide standard, thus the name)
it persuaded robot makers Kawasaki and Nachi to standardize their teaching pendant
designs, which according to Pat DEramo, general manager, Body Operations,
TMMK, slashed training time (the previous line had up to 20 different pendants)
and made it a lot easier to rotate operators from station to station.
The Lego Approach. One of the obstacles in the path to achieving one standard
but flexible do-all machine is part orientation. As assembly line designers
are asked to accommodate a greater variety of products, figuring out how to
move and position parts of widely divergent size and shape can lead to unwanted
customization. Body assembly operations have embraced common locator points
and master jigs that are tied to a specific model as an answer, which essentially
allows electric robots to become the standard piece of equipment. But the flexibility
gained is usually limited to models built off of the same or closely related
platforms.
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When Toyota Motor Manufacturing Kentucky installed its new body line, it persuaded robot makers to commonize teaching pendants on one standard. The old line used up to 20 different units.
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Engine and transmission assembly, on the other hand, is eschewing the traditional
manufacturing lugs used to locate components for an approach that can accommodate
several different architectures on the same line. Brown likens the method to
building with Lego blocks since you can create some very elaborate structures,
but they are all made up of simple, standard parts. In essence, it is a way
to achieve the end result provided by custom-designed parts handling equipment
by plugging together a varying number of standard modules. Brown explains, If
you just need to find the part and grab it, you need tool X. If you have to
grab it and lift it, you need X and Y. Grab it, turn it, lift itX,Y and
Z. They are all standard packages that you add on as you need.
Catalog Shopping? And that may be as close as the industry gets to a standard
piece of assembly equipment in the foreseeable future: many standard and interchangeable
modules, but not one machine that does it all. The greater gains will probably
come in using those modules to create ever more flexible lines. For example,
Brown says that in 10 years we will see assembly lines that switch between building
engines and transmissions without re-tooling. And as far as our central question
about catalog shopping goes, Brown responds, Weve come a long way
from dedicated tooling, but I dont know if we will ever get to the point
where companies will be able to order a line from a catalog. However, if we
know some basic initial product information and rough production rates, we can
order much of whats needed to equip a line and quickly begin to concentrate
on the dedicated tooling. And thats a lot closer than we have ever been
in the past.