Using Flow Charts

Flow charts can be extremely useful tools in a lean Six Sigma transformation. This is especially true in the initial stages where an organization's current process and structure are evaluated. Flow charts simplify the process of identifying and prioritizing issues that need to be addressed.

Understandably, not all flow charts measure the same things or apply to every environment. The basic concept of breaking down a process into its components for evaluation within context is common. The information represented in the chart, and the issue it seeks to address, however, can differ.

Process Flow Charts

A commonly used variation is the Process Flow Chart. As the name implies, this variation represents the flow of materials and activities involved in a particular procedure. It is also known as Process Mapping or Flow Diagramming. These charts are complete representations in that they document a process' start and finish as well as everything in between.

A Process Flow Chart is particularly helpful to:

  • clarify a group's understanding of a process
  • identify non-value-added elements of a process
  • provide a basis for improved teamwork and communication
  • maintain uniformity in examining a process

The various elements of a process are represented by different. These symbols represent critical aspects, such as a process' beginning or end point, activities, decisions and delays. Textual information, such as the amount of time involved in an activity or delay can increase the chart's value as a lean Six Sigma tool significantly.

Value Added Flow Charts

A Value Added Flow chart takes mapping out a process one step further. It is a device used to improve cycle times and productivity, as well as identify sources of waste. While a Process Flow Chart illustrates activities and materials involved in a process, a Value Added Flow Chart focuses upon opportunities for improvement and waste elimination. This charting tool, therefore, is particularly significant to lean Six Sigma efforts.

In these charts, activities are classified by whether or not they add value to the overall process. This classification is based upon whether an activity improves a product's form, fit, or function on the first pass through the process.

Like a Process Flow Chart, this chart outlines a process from start to finish. The time for each step is also noted and the total for all steps (Total Cycle Time) is included in the chart. Steps that do not add value, such as inspection, testing or inventory, are segregated, and the cumulative time spent on these activities is calculated. This figure identifies the waste to be eliminated if these steps were removed or improved. Time spent on the value-added steps (Value-Added Cycle Time) is also tallied. The non-value added steps are then analyzed to determine areas for improvement and waste elimination. The value-added steps are also examined for possible improvements. From this information, a targeted process is charted. This allows for the identification of any sources of waste as the process moves towards this target.