Page 98 - The Handbook for Quality Management a Complete Guide to Operational Excellence

84 I n t e g r a t e d P l a n n i n g S t r a t e g i c P l a n n i n g 85

Notice the use of the word evaluate in this step. This word is
emphasized for a good reason. From the preceding examples—
buying more equipment or adding shifts, or overtime—it should
be clear that there’s more than one way to skin a cat. Some
alternatives are less expensive than others. Some alternatives are
more attractive for reasons that can’t be measured directly in
financial terms (e.g., being easier to manage). In any case, a choice
on the means to elevate will usually be required, so jumping on the
first option that you think of might not necessarily be a good idea.
One of the reasons to favor one elevation alternative over another
is the identity of the next potential constraint. Constraints don’t
“go away,” per se. When a constraint is broken, some other factor,
either internal or external to the system, becomes the new system
constraint—albeit at a higher level of overall system performance,
but a constraint nonetheless. It’s possible that the next potential
constraint might be more difficult to manage than the one we
currently have; it might reduce the margin of control we have over
our system.
It’s also possible these alternatives might drive the system constraint
to different locations—one of which might be preferable to the
other. Or it could be that dealing with the potential new constraint
might require a much longer lead time than breaking the current
constraint. In this case, if we decide to break the current constraint,
we would want to get a “head start” on the tasks needed to exercise
some control over the new constraint.

Ineffective Elevation: An Example
For example, one company involved in the manufacture of solid
state circuit boards found its constraint to be the first step in its pro-
cess: a surface-mount (gaseous diffusion) machine (Schragenheim
and Dettmer, 2000, Chap. 2). Without considering which other
resource might become the new constraint, they opted to purchase
another surface-mount machine. This certainly relieved the origi-
nal constraint. But the automated test equipment (ATE)—about
eight steps down the pro duction line—became the new constraint,
and managing the constraint at this location was no easy task. It
was more complex to schedule at that point, and it suffered more
problems. Moreover, moving the con straint out of the ATE section
was even more challenging. Buying more ATE was more expen-
sive than buying additional surface-mount equip ment. Finding
qualified ATE operators was also more difficult.
In short, it took more time, effort, and money to manage or
break the ATE constraint than it did to break the surface-mount
constraint. Had the company been able to anticipate that ATE

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