Evaluating Sources of Waste for Lean Manufacturing Six Sigma

Before a lean manufacturing Six Sigma transformation can occur, sources of process waste must be identified. Within a manufacturing environment, waste typically occurs as a result of issues with production, waiting, transportation, processing, inventory, motion and product defects. Targeting evaluation efforts in these areas is an effective means of applying a lean manufacturing Six Sigma program.

Sources of Waste

  • Overproduction - This is by far the most common source of waste in manufacturing. Producing a greater number of units than warranted by consumer demands leads to a number of issues within an organization. The excess inventory generated creates additional handling, space, work force, documentation and machinery requirements, as well as the accumulation of unnecessary interest charges. Lean manufacturing Six Sigma evaluations of production must accept the fact that equipment and employees can meet customer requirements and be cost efficient without full utilization
  • Waiting time - Use of time is frequently a source of waste in manufacturing as well. Waste arises when workers produce meet their quota of units, but are then idle. If the machine operation cycle does not match the worker's availability, additional waste can also occur. Evaluation efforts should look to the relationship between the speed of work and volume produced. Synchronizing both to meet actual demands reduces waiting time.
  • Transportation - Unnecessary double and triple handling of finished and unfinished units can occur as a result of inefficient floor and storage layout. Use of temporary or mobile storage locations aggravates the situation. Evaluation of transportation waste should focus on production floor layout, process coordination and organization.
  • Processing - Poorly or irregularly maintained equipment can lead to waste in the production process. Well maintained machinery, on the other hand, requires less labor to produce defect-free units. Lean manufacturing Six Sigma evaluation efforts should focus upon the effectiveness of maintenance programs to identify possible sources of waste .
  • Inventory - Inventory size is tightly linked to production volume. Overproduction leads to excessive inventory which in turn creates a spiral of wasted space, handling, storage costs, etc. Analyzing inventory-related wasted should focus upon issues with scheduling, machine failure, quality, transportation, delivery, line function, set up and overall organization
  • Motion - Time spent in non value-adding activities is a source of waste. Activity is not the same as productive work. This type of waste typically appears as workers spending an excessive amount of time spent searching for parts and tools or moving from one machine to another.
  • Product defects - The volume of defects is linked to the volume of waste throughout the manufacturing process. Additional expenditures occur as a result of additional rework, material, labor and warranty demands caused by defective products. Evaluation efforts should target both the defects and their causes.