Statistical Process Control charts have been called the Voice of the Process. Progressive manufacturers utilize control charts to “listen” to their processes so that potentially harmful changes will be quickly detected and rectified. However, not all SPC programs deliver to their highest capability as there are many elements to get right to achieve maximum utility. Highly effective SPC programs combine technical competencies, such as using an appropriate chart and sample size for the application, with effective management techniques such as enabling operator buy-in and involvement. This article identifies ten keys that unleash the power of SPC. [Read more…]
The Integral Concepts article series
This article series explores essential concepts and methods for deploying Statistical Process Control (SPC) and Design of Experiments (DOE) effectively in your production operation. The articles focus on essential concepts as well as important topics that often not covered in basic SPC or DOE training programs. Some related statistical methods are also covered in a few of the articles
What is the Relationship between Process Stability and Process Capability?
Process Stability and Process Capability are both extremely important aspects of any manufacturing process. Often the concepts behind process stability and process capability and the relationship between them are misunderstood. This article attempts to clarify both ideas and the relationship between them. [Read more…]
Motivation for Structured Experimentation
When planning and designing an experiment, it may be tempting to try and accomplish all the objectives is a single experiment. The thinking is often that experimentation is time consuming and expensive, so one experiment must be better than multiple experiments.
However, in general, it is a good idea to plan for multiple experiments which often is a much more efficient approach. We like to think of experimentation as a methodology that is best implemented in phases. We define experimental phases as: [Read more…]
Modeling and Optimizing Process Behavior using Design of Experiments
Experimentation is frequently performed using trial and error approaches which are extremely inefficient and rarely lead to optimal solutions. Furthermore, when it’s desired to understand theeffect of multiple variables on an outcome (response), “one-factor-at-a-time” trials are often performed. Not only is this approach inefficient, it inhibits the ability to understand and model how multiple variables interact to jointly affect a response. Statistically based Design of Experiments provides a methodology for optimally developing process understanding via experimentation. [Read more…]
What is the Philosophy of Process Control?
Ask people involved with the design and manufacture of a product the following question: “What is Quality?” Many if not most of the responses will be some form of the following: “Quality is ensuring that our products meet the customer (or engineering) specifications. Unfortunately, this leads to a “conformance to specifications” or a “Product Control” approach to quality. [Read more…]