Jim L. Smith

It did not happen quickly but advocates of Six Sigma and lean methodologies have worked together to achieve a partnership of both approaches.

In my two previous columns I discussed specification limits and process control limits, which led to thoughts about product disposition limits.

In my previous column I discussed the role of specification limits in manufacturing, which led to thoughts about process control limits.

It is still surprising how many people, from engineers to managers to quality professionals to technicians, possess limited understanding of product and process (manufacturing) limits.

Certainly there are many types of teams, but in recent times it’s been similar to the alphabet soup of quality tools and techniques. Top executive teams, project teams, six sigma teams, cross-functional teams, improvement teams, self-directed teams, and ad hoc teams are some of the more recognizable forms.

Many quality professionals, including statisticians, have remained mired in their rapidly diminishing consultative roles of teaching statistical tools, analyzing data, designing experiments and performing internal consulting duties while having few leadership responsibilities and limited accountability.

I have spent numerous years working in and with all aspects of quality. During my earliest time in industry solving problems was more of a singular focus, but over the years the focus has become more of a team effort.

It’s safe to say that all quality practitioners are familiar with the control charting terms “common cause” and “special cause” variation. However, how many have really thought about their interpretations and associated action plans which could also add to variation? 

When faced with most problems dealing with processes, products, or service, quality professionals typically implement two types of remedial actions which were handed down to us by experts like Dr. Joseph M. Juran, Dr. Frank Gryna, et al. “Control of nonconforming product” and “root cause analysis with corrective action” are two separate and essential processes.

Quality at the source (QATS) has been used well before lean manufacturing became so popular. Many people in the quality function have applied the principles especially at critical work areas to detect nonconforming items and prevent them from moving forward in the process.