Aplikace nových poznatků DOE a metodika Six Sigma u výrobků, tvořených velkým počtem komponent

Abstract

The dissertation focuses on application of new approaches in area of design of experiments and Six Sigma methodology for products consisiting of a large number of components. In the theoretical part are presented in detail the most used methods of continuous quality improvement. Attention is focused on the Six Sigma methodology and its potential application as problem solving method. Critical analysis has been subjected to diagnostic journey of the Six Sigma methodology. To apply Six Sigma as a problem solving method the extended model C-DMAIC-S was proposed. This model contains two additional phases: • Contain to protect the customer from the symptoms of the problem until the implementation of permanent corrective actions, • Standardize which has a preventive purpose. To eliminate weaknesses in the diagnostic journey which is critical for problem solving they were proposed innovative techniques of root cause identification. This was done by exploiting synergies with the methodology Shainin RedX®, often used in the automotive industry, which is based on convergent approach to identify the potential causes leading to improved efficiency in the diagnostic journey. The goal of the application of extended model C-DMAIC-S and the increased effectivness of Six Sigma diagnostic journey is to apply Six Sigma methodology as problem solving tool for multicomponent systems. Application of the design of experiments is an important part of the Six Sigma methodology. Execution of the experiment in a fully randomized way is often limited due to time, material, financial or technical reasons. In such cases an appropriate choice would be the split-plot design of experiments. Practical part of the thesis is fully dedicated to application of proposed C-DMAIC-S model, improved diagnostic journey of Six Sigma as well as Split-Plot Design of Experiments to case of scuffed high-pressure injection pumps. High-pressure injection pump is an example of multicomponent system consisting of 107 components.