Control Plans aid in the manufacture of quality products to meet customer requirements. They provide a written description of the system and mechanisms to minimize product and process variation. The Control Plan augments the information provided in detailed operator instructions. Control Plans may apply to an individual part or product or to a family of similar items produced using the same process and source/equipment.
Control Plans describe the actions required at each step in the process to assure that all process outputs will be in a state of control. During regular production runs, Control Plans provide the process monitoring and control methods used to control part or product characteristics. During product development the Control Plan is used to document and communicate the initial plan for process control. During production, it guides Manufacturing in how to control the process and insure product quality. The Control Plan is updated as the design changes, the process changes or measurement systems and control methodologies are improved. Control Plans are conceptually similar to the fourth phase of QFD, process/quality control planning and are often used in place of preparing this matrix. An example of a control plan is shown below.