Six Sigma Analysis

INTRODUCTION

The history of Six-Sigma

The roots of Six Sigma as a measurement standard go back to Carl Frederick Gauss (1777-1885) who introduced the concept of normal curve. Six Sigma as a measurement standard in product variation can be traced back to the 1920Ð'Ò's when Walter Shewhart showed that three sigma, from the mean is the point where a process requires correction.

As history would seem to have it, the beginnings of Six Sigma really come from 1979 when an exasperated Motorola executive named Art Sundry said, at a meeting, "The real problem at Motorola is that our quality stinks!". Apparently, this statement led to series of activities that in turn led to the discovery of the crucial correlation between higher quality and lower development costs in manufacturing products of all kinds. The problem was that the common thought was that quality initiatives simply cost too much money. What Motorola realized is that if these initiatives were done right, improving quality would actually reduce costs. Motorola decided to take the approach that high quality products should actually cost less to produce. Motorola reasoned that the highest quality producer should be the lowest cost producer.

THEORETICAL ANALYSIS OF THE CONCEPT OF SIX-SIGMA

What is Six-Sigma

Six-Sigma has at least three different meanings depending upon the context; there is not one answer to what is Six-Sigma.

The first answer to what is Six-Sigma is that it is a management philosophy. Six-Sigma is a customer based approach realizing that defects are expensive. Fewer defects mean lower costs and improved customer loyalty. The lowest cost, high value producer is the most competitive provider of goods and services. Six-Sigma is a way to achieve strategic business results.

Another answer to what is Six-sigma is Six-Sigma is a statistic. Six-Sigma processes will produce less than 3,4 defects or mistakes per million opportunities. Many successful six sigma projects do not achieve a 3,4 defects or less. That just indicates that there is still opportunity.

A third answer to what is six sigma is that six sigma is a process. To implement the Six-Sigma management philosophy and achieve the Six-Sigma level of 3,4 defects per million opportunities or less there is a process that is used. The Six-Sigma process is define, measure, analyze, improve and control DMAIC.

When answering the question what is Six-Sigma we must understand that Six-Sigma is not a set of new or unknown tools. Six-Sigma tools and techniques all are found in total quality management. Six-Sigma is the application of the tools on selected important projects at the appropriate time.

Statistical Six-Sigma Definition Ð'- How does it work?

What does it mean to be "Six Sigma"? Six-Sigma at many organizations simply means a measure of quality that strives for near perfection. But the statistical implications of a Six Sigma program go well beyond the qualitative eradication of customer perceptible defects. It's a methodology that is well rooted in mathematics and statistics.

The objective of Six Sigma Quality is to reduce process output variation so that +six standard deviations lie between the mean and the nearest specification limit. This will allow no more than 3,4 defect Parts Per Million (PPM) opportunities, also known as Defects Per Million Opportunities (DPMO), to be produced.

As the process sigma value increase from zero to six, the variation of the process around the mean value decreases. With a high enough value of process sigma, the process approaches zero variation and is known as "zero defects."

APPLICATIONS AND BENEFITS OF SIX-SIGMA

- Integrating Six Sigma and Lean Manufacturing

When companies such as Mercedes, Pella, Maytag and hundreds of others began their lean journeys, they turned to the Lean Production System and kaizen to get moving. As they reduced unneeded inventory-like lowering a water line to expose the rocks-they discovered the need for even more advanced methods of determining the root causes of abnormalities.

The Lean Sigma transformation has taken these companies from an intuitive level, in which trained operators and engineers can begin to see and Ð'- fix issues, to the more complex. At the higher level, where issues are not obvious to the casual observer, we use statistical tools to uncover abnormalities.

Lean Sigma uses both Six Sigma and lean principles to reduce defects and drive cultural change. Focused on lead-time and variability reduction, Lean Sigma is a methodology aligned with a time-based strategy at the speed of Kaizen Breakthrough.

Lean Contributions:

Ð'* Identification of defects is immediate with one-piece flow

Ð'* Kaizen is efficient method to eliminate defects because of its bias for action, extensive team involvement, and immediate corrective action.

Six Sigma Contributions:

Ð'* Focused on reducing variation

Ð'* Focused on specific target areas

Ð'* Capable of focusing on defects caused by the interaction of several variables

Ð'* Measurement focused

The LeanSigma Transformation

Each level of transformation takes place in a cross-functional team environment, with collaboration and data collection and analysis driving cultural change.

In the more advanced stage of the transformation, Lean Sigma Champions, Black Belts, and Green Belts are deployed throughout a business to root out variation and abnormality using statistical tools. To launch this stage successfully, flow should first be established, either on a model line or company-wide.

Once flow is established, our "best practice" is first to raise awareness among the professionals who will oversee the Lean Sigma effort:

Ð'* Champions receive a week of training, during which executives assess their current metrics and then focus on defining the business objectives that will drive projects.

Ð'* Black Belts receive four weeks of training, culminating in a project that must show substantial financial benefit to the company. After training, the