The
history of lean manufacturing shows that it is usually feasible, if not
downright simple, to eliminate waste from a process. This cannot
happen, though, until the waste is recognized for what it is. One of
Henry Ford's key success secrets was the ability to identify waste that
others overlooked even though it was (with the benefit of hindsight) in
plain view, and this skill is this article's key takeaway. The specific
technologies or process improvements in the examples may or may not be
applicable to the reader's industry, but their chief purpose is to
illustrate the thought process behind them.
Overview: Waste Hides in Plain Sight
"How
many of our competitor's workers does it take to change a light bulb?
Four: one to hold the bulb, and three to turn the ladder." This joke is
funny until we discover jobs or processes in our own workplaces that
waste even more than 75% of the labor, cycle time, materials, and/or
energy involved. In
My Life and Work, Ford, who grew up on a farm, cited waste as great as 95%.
I
believe that the average farmer puts to a really useful purpose only
about 5% of the energy that he spends. …Not only is everything done by
hand, but seldom is a thought given to logical arrangement. A farmer
doing his chores will walk up and down a rickety ladder a dozen times.
He will carry water for years instead of putting in a few lengths of
pipe.
The takeaway is that,
unlike poor quality, waste effort is built into the job where it is then
taken for granted. The farmer would quickly notice a sick animal or
pest-infested crops but, because the chores get done, he does not notice
the waste of his labor. In 1926, Ford in
Today and Tomorrow elaborated,
Time
waste differs from material waste in that there can be no salvage. The
easiest of all wastes, and the hardest to correct, is this waste of
time, because wasted time does not litter the floor like wasted
material.
Again, nobody notices
the waste because the job gets done and, in the absence of problems
such as scrap or rework, nobody thinks to question the job's design. As
an example, Edward Mott Woolley described a fabric folding operation in a
bleaching and dyeing factory as follows:
But
all [employees] took two steps to the right to secure their cloth,
returned to the tables, folded the stuff and deposited it on another
pile two steps to the left. That had always been the practice; no one
had ever thought to question it. (The System Company, 1911, 41)
Henry
Ford wrote later that pedestrianism is not a well-paying line of work,
and a simple workplace rearrangement halved the number of steps the
bleaching and dyeing factory's workers had to take. The changes doubled
their output, and probably reduced their physical effort in the bargain.
Brick laying, as practiced into the early 20
th
century, is a classic example. Masons bent over to pick up each brick, a
procedure that required the worker to lower and raise most of his body
weight to add 5 pounds' worth of value (the brick) to the wall. Nobody
questioned the procedure because the walls got built, although the
workers went home with sore muscles and relatively low pay because they
could lay only 125 bricks an hour.
Then
Frank Gilbreth introduced a non-stooping scaffold that delivered bricks
at waist level. Masons could now lay 350 bricks an hour, and with far
less physical exertion. This resulted in higher pay, lower prices for
customers and higher profits for the construction companies. A
YouTube video
compares the before and after situations, and you can actually see a
worker bending over to get each brick. As this article promised earlier,
the joke about the light bulb is far less funny when we recognize that
the centuries-old method of brick laying wasted almost two-thirds of the
mason's labor, and therefore his working life.
Gilbreth's
movies can be used today to sensitize workers, engineers and
supervisors to the kind of waste motion that is built into many jobs.
They also underscore the value of making videos of jobs, as long as the
workers understand that the objective is to evaluate the job designs
rather than the workers. It might even be instructive to have the
workers mark segments of the videos of their jobs (e.g. electronically)
in green, yellow and red to indicate value-adding, value-assisting, and
non-value-adding activities respectively.
If
we return to the light bulb joke, factories and large businesses
recognized long ago that having even one worker climb a ladder to
replace a light bulb wastes the time of maintenance workers, and
therefore money. This is why telescoping light bulb changers were
invented more than 100 years ago. It may be acceptable to climb a
ladder, or use hand tools, for occasional household chores and tasks,
but no manufacturing or construction business would dream of using
hand-powered tools for everyday work. If dozens or hundreds of screws or
bolts must be tightened every day, power tools are used.
The
same basic principle, namely that almost any unscientifically-designed
job consists primarily of waste, carries over into the controversy over
the minimum wage in fast food industries. The underlying principles and
concepts again carry over into manufacturing industries.
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