Page 141 - Six Sigma Demystified

122 Six SigMa DemystifieD

• Commonality of setups for product families. When the same setup proce-
dures are established for multiple items, there are naturally fewer in-
stances of change required, reducing the setup time. This is the 5S
principle of standardization.
• The 5S tools of sorting and straightening also help to reduce movement
and wait times.

Location tasks are those associated with positioning or placement during
setup. Examples include setting temperature profiles for heating, adjusting cut-
off length for a specific product, and placing the chunk of deli meat in the slicer.
Actions to reduce the time associated with location include

• Poka yoke (the Japanese term for mistake- proofing the process), as dis-
cussed in Chapter 7
• Commonality of setups, as mentioned previously (the 5S tool of standard-
ization)

Adjustment refers to tasks associated with ensuring correct process settings.
Examples include monitoring the temperature of a furnace, checking cutoff
length, and proofing copy before printing. A suitable action to reduce adjust-
ment time is process control. If the process is more repeatable, then adjust-
ments are not necessary. Often this is achieved though robust design methods,
as discussed in Chapter 7.
A Pareto diagram can be useful to prioritize the setup- time categories. In the
example shown in Figure 6.1, location and preparation dominate the setup and
thus are natural targets for improvement.
George (2002) recommends the following four- step approach to reduce
setup times:

• Classify each setup step as either internal or external. Internal steps are
those which are done while the process is inactive. External steps are done
while the process is operating.
• Convert as many internal steps as possible to external steps.
• Reduce the time for the remaining internal steps.

• Eliminate adjustments.

In converting as many internal steps as possible to external steps, the non-
operational process time is reduced. For example, if money is collected from
customers while they are waiting for their burgers to be cooked rather than