Walter A. Shewhart

Early Life and Education

Walter Andrew Shewhart was born on March 18, 1891, in New Canton, Illinois, USA. He was the son of Anton and Esta Barney Shewhart. Shewhart's early education was in the local public schools, and he later attended the University of Illinois, where he earned a Bachelor of Science degree in electrical engineering in 1913. He continued his education at the University of California, Berkeley, where he received a Master of Science degree in physics in 1914. Shewhart then pursued a Ph.D. in physics at the University of California, Berkeley, which he completed in 1917.

Career and Contributions

Bell Telephone Laboratories

In 1918, Shewhart joined the Western Electric Company, which later became part of Bell Telephone Laboratories. It was here that Shewhart made his most significant contributions to the field of quality control. At Bell Labs, Shewhart was tasked with improving the reliability of the manufacturing processes for telephone equipment. This led him to develop the concept of statistical quality control (SQC).

Development of Control Charts

One of Shewhart's most notable achievements was the development of the control chart, a tool used to monitor the stability of manufacturing processes. The control chart is a graphical representation of a process over time, with control limits that indicate the expected range of variation. If the process data falls within these limits, the process is considered to be in control. If the data falls outside the limits, it indicates that the process may be out of control and requires investigation.

Shewhart's control charts were revolutionary because they provided a systematic method for distinguishing between common cause variation (inherent to the process) and special cause variation (due to external factors). This distinction is crucial for effective process improvement.

Shewhart Cycle

Shewhart also introduced the concept of the Plan-Do-Check-Act (PDCA) cycle, which is often referred to as the Shewhart Cycle or Deming Cycle. The PDCA cycle is a continuous loop of planning, doing, checking, and acting, aimed at achieving continuous improvement in processes. This methodology has been widely adopted in various industries and is a cornerstone of modern quality management practices.

Publications and Legacy

"Economic Control of Quality of Manufactured Product"

In 1931, Shewhart published his seminal work, "Economic Control of Quality of Manufactured Product." This book laid the foundation for the field of statistical quality control and introduced many of the concepts and tools that are still in use today. Shewhart's work emphasized the importance of using statistical methods to understand and control variation in manufacturing processes.

Influence on W. Edwards Deming

Shewhart's work had a profound influence on W. Edwards Deming, who is often credited with popularizing statistical quality control in Japan and the United States. Deming worked closely with Shewhart at Bell Labs and adopted many of his principles and methods. Deming's own contributions to quality management, including the Deming Prize and the Deming System of Profound Knowledge, are deeply rooted in Shewhart's pioneering work.

Impact on Modern Quality Management

Shewhart's contributions to quality control have had a lasting impact on modern quality management practices. His control charts and the PDCA cycle are fundamental tools in the field of quality management and are widely used in industries ranging from manufacturing to healthcare.

Six Sigma

The principles of statistical quality control that Shewhart developed are also integral to the Six Sigma methodology. Six Sigma is a data-driven approach to process improvement that aims to reduce defects and variability in processes. The use of control charts and the emphasis on understanding and controlling variation are key components of Six Sigma, reflecting Shewhart's influence.

Total Quality Management (TQM)

Total Quality Management (TQM) is another quality management approach that has been influenced by Shewhart's work. TQM focuses on continuous improvement, customer satisfaction, and the involvement of all employees in quality initiatives. The PDCA cycle, in particular, is a central element of TQM, demonstrating Shewhart's enduring impact on the field.

Personal Life and Death

Walter A. Shewhart was known for his modest and unassuming personality. He was deeply committed to his work and made significant contributions to the field of quality control throughout his career. Shewhart passed away on March 11, 1967, leaving behind a legacy that continues to shape the field of quality management.

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