There are a lot of different ideas about what SPC is. Some see SPC as the use of control charts to analyze data. Other see it as a complete management system used to continuously improve quality and productivity. We see SPC as a complete management system to continuously improve quality and productivity because that is the ultimate goal of SPC. It is very similar to six sigma but there is one bug difference. Six sigma does not take into account that implementation and analysis must be done very efficiently. In a good implementation you need to use a real-time SPC solution to implement continuous improvement efficiently.
One of the first requirements to get maximum results is that SPC should be implemented in every level in the organization. To control a process we need to apply SPC real-time. When we measure we need to register the data immediately and plot the results in a control charts. When the process is out of control we need to find the root cause of the out of control and take corrective actions. It makes no sense to only analyze the data at the end of the day because then we can only report about the quality produced and the fact that the process is not in control. It is often too late to get proper information about the root cause take corrective actions. We call this the control level.
Operators should be empowered to find the root cause and take corrective actions. If they are no capable of finding the root cause or are not allowed to make the required corrective actions. They should inform the production support level (engineers, production management or maintenance) and they have the responsibility to improve the process inputs and provide feedback to the operators how the process is improved. We call this the improvement level. Production management needs to set targets for continual improvement so priorities can be set. They also should provide the means to improve the production factors. We call this the planning level.
If SPC is implemented like described you might get maximum results from your SPC or six sigma implementation.