8.9. Conclusion

The original project goal was to eliminate the periods of crisis with a goal of achieving a yield rate of 95 percent. One and a half years have now passed since completing this project, and although very few batches do fall slightly below the lower limit for color index, this issue is resolved by blending low color index batches with high color index batches. To date, the molding plant has not rejected a single batch of white polymer since the changes have been implemented.

The savings from rejected batches alone are slightly over £750,000 per annum. Additionally there are now no processing restrictions on the molding plant, resulting in an additional annualized margin of £2,100,000 per annum and a very happy customer. The actual costs incurred on the project were minimal.

This was the project that convinced the skeptics, Edward included. It solved a major manufacturing problem with huge business benefits. In the final project close-out meeting, the key lessons were summarized as follows:

• Never trust a measurement system—it was only when these issues were resolved that it was possible to get meaningful results from the analysis.

• DMAIC methodology in conjunction with the Visual Six Sigma Roadmap delivers high levels of process understanding in a simple, straightforward manner.

• Visual Six Sigma techniques enable technical and business users to apply the principles of statistical thinking to solve problems rapidly and effectively.

• Visual Six Sigma greatly facilitates the communication of results to a wide audience in a simple visual form.