Deming Circle or PDCA Cycle describes an iterative three or four-phase process for learning and improvement. PDCA stands for Plan – Do – Check – Act, the origin of the process lies in quality assurance. The term Deming Circle is derived from W. Edwards Deming. The American physicist and statistician had studied with Shewhart, taken up and disseminated his ideas and thus significantly influenced quality management. As a result, the cycle was attributed to him and in many countries referred to as the Deming Circle or similar. Deming himself spoke throughout the Shewhart cycle as he attributed the idea to Shewhart.
The Four Steps of PDCA
Deming added another step to Shewhart’s three-step process to represent evolutionary quality development. This gave the process the four-stage form of presentation that is customary today. A Shewhart cycle became a stage in the continuous improvement process of a system. According to Deming’s preferred human relations approach, he focused on the work system: “Go to the place of action” and above all puts the employees on-site with their exact knowledge of the situation at the workplace at the centre of the planning. The PDCA cycle consists of four elements:
the respective process must be planned before its actual implementation: Plan includes the identification of potential for improvement (usually by the employee or team leader on site), the analysis of the current state and the development of a new concept (with intensive involvement of the employee).
Contrary to popular belief, Do does not mean the introduction and implementation on a broad front, but the testing or testing and practical optimization of the concept with quickly realizable, simple means (e.g. provisional devices) at a single workplace [again with strong involvement of the employee.
the process flow is implemented on a small scale and its results are carefully reviewed and, if successful, generally approved for implementation on a broad front.
In the Act phase, the new general requirement is introduced on a broad front, codified and regularly reviewed for compliance (audits). This is a “big action” that in individual cases can include extensive organizational activities (e.g. changes to working schedules, NC programs, master data, the implementation of training, adaptation of organizational structures and processes) as well as significant investments (at all comparable workplaces, in all plants). The improvement of this standard in turn begins with the Plan phase.
Applications of PDCA
The PDCA cycle describes the phases in the continuous improvement process (CIP). CIP is the basis of all quality management systems. Thus, the company pursues a continuous improvement of processes and procedures to improve the efficiency, customer and employee satisfaction of the company.
In industrial companies and the service sector, it is one of the standard procedures. After each PDCA cycle, the measures shall be standardized by an SDCA cycle. After each introduction of a defined standard (Standardize), this standard is practised (Do), the procedure is checked for correctness and functionality (Check) and if necessary changed (Action). This action is then usually the planning of another PDCA cycle.