Page 47 - Lean six sigma demystified

26 Lean Six Sigma DemystifieD

Step 3. Make the invisible visible. If you want to reduce delay, defects, and
deviation,

1. Reduce delay

• Flowchart or value stream map your process.
• Analyze where most of the delay occurs and eliminate it.
2. Reduce defects
• Count your misses, mistakes, and errors and plot them on a control
chart.
• Categorize your misses and display them using a Pareto chart.
• Analyze the root causes of these mistakes and how to prevent them
using a fish bone diagram and countermeasures matrix.
3. Reduce deviation

All processes produce varying results. A hospital admission process may take
a little more or a little less time. Housekeeping staff may take a little more or a
little less time to clean a room. A manager may take a varying amount of time
to make a decision. Getting bids for purchases will take varying amounts of
time. Getting approvals for purchases takes a widely varying period of time.
A bottling factory may fill each bottle a little more or a little less. An injection-
molding factory may make bottles that are a little bigger or a little smaller, or the
neck or caps may be a little bigger or a little smaller. Variations in temperature,
pressure, and time of day, shift workers, or whatever may cause these variations.
To reduce variation, you will want to

• Measure your performance in cycle time, length, width, weight, volume,
or money
• Use histograms and control charts to understand the variation
• Analyze the root causes of variation and reduce it

Sustain

Perhaps the most difficult part of any change is sustaining the new way of
thinking, being, doing, or acting. It’s easy to fall back into the old rut.
Step 1. Make the invisible visible. Start using special graphs called control
charts and histograms to monitor the behavior of your processes. To use
them; you just have to know how to read them. Control charts will tell you