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4. After the energy high has worn off, energy
levels usually deteriorate over time into fatigue.
People then concentrate poorly. They make more
mistakes and miss opportunities to catch problems
during this low energy time.
Regarding the shutdowns themselves, I learned that
no two shut-downs are the same. Each one is a new
project. Like projects, shutdowns are executed better
if they start on time, everyone is synchronized, and
everyone is fully informed. Uncertainties arise in
nearly every shutdown; they often multiply relative to
the calendar length of the shutdown. Local mechanics,
technicians, and engineers, dedicated to the site and
knowledgeable of the specific
equipment and processes, are the best resources for
doing the work, especially the critical, non-routine
work. Because many of the upgrades have been developed
internally, they should be implemented by those
individuals responsible for the upgrade.
Learning
curve studies indicate that repeat and similar
maintenance work can be completed faster by using the
same people each time. Usually these people are the
local resources who get involved each time. We will
call the local work area mechanics dedicated to the
equipment and processes, key mechanics.
Given these general
observations, it was clear that more frequent short
shutdowns would be beneficial for the work area. My
next step was to develop a plan that was workable for
both production and maintenance. By intuition, a
strategy began to emerge.
Critical Chain¹ by Eli
Goldratt was not yet available at the time, however,
it is now apparent that the strategy was consistent
with the theory of constraints (TOC), as presented in
his 1997 book. Critical Chain explains the steps and
power of addressing Shutdown TOC. It also supports the
principle that without attention to detail, most task
estimates are inflated significantly.
The annual operation is
like a critical chain. Shutdown events, just like
production time, experiment time, and process
verification time, are all part of the annual
timeline. A shutdown must be treated as the critical
chain's priority event during its execution. If this
is accepted, the total community will assist in
supporting the success of the shutdown through minimal
time and good startups. Each shutdown includes several
TOC components. These can be called: identify,
exploit, subordinate, elevate, and
go back.
Identify.
The first step in a
shutdown is to identify the key constraint. In this
example, as is the case with many maintenance
organizations staffed primarily with shift mechanics,
the key constraint was the availability of the local
resources. These key mechanics are extremely valuable
in that they know: the process, the equipment, the
operation systems, and the geography of the building.
People coming to help from other areas would not be as
effective as the local people with local knowledge.
Operators with mechanic skills can also be very useful
and should be part of the resource base. Keep in mind
that the cost of using local resources is already
covered in the maintenance operating budget. |
