Statistical Process Control (SPC) - The Philosophy & How it Works

SPC: The Philosophy4. Improved market share leads to more jobs.
The primary emphasis of SPC is usually in the area ofEverybody wins - customers and suppliers. It all
quality improvement; however, the methods employeddepends upon improving quality. A determined, daily
can also improve human relations, productivity andpursuit of improved quality and productivity is not
profits. SPC, properly applied, will enhance the goodoptional in the world market. It is a necessity.
things you are already doing and highlight areas whereSPC: How It Works
improvements are needed. Really, it's just another toolA simple way to demonstrate how SPC works is to
to help you manage your business more effectively.contrast the "Classic" Control Cycle and the "SPC"
SPC is not a quick solution for problems. Rather, it is anControl Cycle. Usually, companies will have a system
approach to quality management that focuses onof inspection which is a sorting method. In other words,
facts and involves everyone in the organization.we produce product and then sort the good from the
Achieving results will take time, patience andbad after production. This leads to high costs, high
commitment on your part and on the part ofscrap and lower quality products being shipped to
manage­ment.customers. This is referred to as the "Classic" Control
The basic quality philosophy must be "Do it right theCycle.
first time." This should be true of all groups in theThe "SPC" Control Cycle uses a different approach.
organization - engineer­ing, manufacturing,With SPC methods, the process tells us what is
purchasing, everybody. SPC helps through reducinghappening during the production of our products so
process and product variability, thus increasing theadjustments can be made to the process before
quality levels of goods as they are produced.producing out-of-specification products. This method
The basic SPC philosophy incorporates the followingresults in reduced variability in our products, reduced
points:scrap, reduced inspection costs and improved quality.
1. Improved quality leads to improved produc­tivity.These two methods of Process Control are depicted
2. Improved productivity leads to lower costs andon the following pages. It's easy to see that SPC is a
lower prices.better way. But.... every­one, especially
3. Improved quality and lower prices lead to improvedmanagement, must be involved!
market share.