Page 47 - The Six Sigma Project Planner

Figure 7. Example of a WBS

Wave Solder Improvement Project

Reduce Solder DPMO
from 5000 to 50

Maintenance Plan Reduce top 3 defect types Establish SPC

Cold solder No solder in hole Pad Lifts

Simple Boards Complex Boards Complex Product B boards without
heat sinks that have holes with no
solder will be a subproject.
With heat sinks Without heat sinks

Product A Product B Product A Product B
For simplicity, not all branches of the WBS are shown in Figure 7. The only branch fully
developed is that of complex boards for the problem labeled “no solder in hole.” On
real projects, upper-level WBS often connect to “off-page connectors,” which are circles
with a letter or number reference to a lower-level WBS chart. The WBS process
continues down to the level where the team feels it can clearly budget, schedule, and
assign activities. Problems defined to this level are sometimes referred to as “tiny.” The
basic idea is to divide and conquer larger issues by reducing them to simple mini-
projects. In this example, the WBS was terminated when a particular type of solder
problem could be assigned to a team that includes a design engineer and a process
engineer.
You may have noticed a resemblance between the WBS diagram and an organization
chart. In fact, the idea behind the WBS is the same as the idea behind a formal
organization: division of work. The work performed by an organization is generally too
complex to be done by a single functional unit, so it is divided according to a logical
scheme. The same is true for the WBS. You may wish to take advantage of this basic
similarity to create the WBS. For example, Microsoft Word includes an organizational
chart tool that can be adapted for creating the WBS diagram.

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