Page 420 - Design for Six Sigma for Service (Six SIGMA Operational Methods)

378 Chapter Ten

7. Document the process. We can use any or all of the process map
techniques:
a. Process flowchart
b. IDEF0 chart
c. Current state value stream map
The goal of the process mapping is to derive the detailed visual definition of
the process and capture the strengths and weaknesses of the process that
will drive the process design and improvement activities.

10.6.3 Process Diagnosis

The goal of process diagnosis is to identify the key weaknesses of the
process and provide the guidelines for process redesign and improvements.
The following approaches are often used in process diagnosis:
1. Value stream map analysis: Value stream mapping can expose non-
value-added activities and process efficiency problems. By using lean
operation principles to analyze the current state value map, possible
improvement ideas can be generated.
2. Process map analysis: A real detailed process map may expose
“hidden factories,” that is, unnecessary loops and steps. This
process map analysis may help to generate process improvement
ideas.
3. Process analysis based on process types: The knowledge outlined in
Sec. 10.3 can also be used to analyze the possible weaknesses of the
process. For example, if we find that our process is an office process
but we use a job shop type of layout, then we can immediately know
that this process type is inefficient for the office process and probably
should change to using several lean work cells.
4. Cause and effect diagram or fishbone diagram analysis.
5. Data collection: Collecting such data as the waiting time, process
time, or equipment and operator utilization for each process step may
help to identify the weak links and bottlenecks of the process.
6. Process simulation: For many service processes, discrete event sim-
ulation can be a very useful tool to evaluate the current process and
identify weak links and bottlenecks.

10.6.4 Process Design (Redesign)

After the process diagnosis step, the weaknesses and bottlenecks of the
process should be known. Now is the time to propose the process change
and generate new designs. New designs can be generated based on