Quality Management

Due to the increased product miniaturization, a number of new applications and market opportunities open up for mechanical micro-manufacturing. In the manufacturing process with part dimensions less than one millimeter and tolerances in the micrometer range occur so-called “size effects”. These prevent a simple scaling of processes known methods from the macro level and lead to an increased occurrence of quality deviations. In conclusion, the process capability according to ISO 21747 is affected and therefore the application of statistical process control (SPC) is more difficult. In this paper, the interaction between technical and logistical quality objectives in terms of logistical quality control are analyzed at the example of micro cold forming. Thereby, methods of statistical process control and fuzzy control are used.

Continuous attempt for improvement as well as the permanent impulse to explore and eliminate failures and flaws belong to the classical quality mindset, which is also reflected in CIP approaches. However, it is often difficult to systematically identify improvement potentials with minimal expenses, especially in knowledge intensive business processes. A purposefully combined disciplines and instruments of quality management, process management and knowledge management enables the development of a maturity model adjusted to the needs of SME. This maturity model, based on the methods of CIP, serves to uncover the potentials in the knowledge process. The following contribution demonstrates the development, application as well as the value of employing the quality-oriented maturity model for knowledge intensive business processes.

Due to increased customer requirements the product quality has become a precondition for the competitiveness of manufacturers. Fundamental for the production of top-quality products are stable and error-free processes. The basic process configuration takes place during the factory planning. If substantial quality related standards are not taken into account at this time, essential modifications could only be realized during the subsequent factory operations with a significant additional effort. Therefore a methodical approach for the planning of quality supportive factories which early integrates the relevant requests in the planning processes is developed at the Institute of Production Systems and Logistics (IFA) of the Leibniz University of Hannover.

To compete in the global environment companies in high wage countries have to separate themselves from competitors from low wage countries by offering customer specific products and services. Due to the rising complexity of these products the steering of the corresponding production systems is getting more and more resource consuming. One way to handle this aspect is developed within the Excellence Cluster “Integrative production technology for High-wage countries” at RWTH Aachen University. Objective is the set up of production systems that are able to produce customer specific products at mass production costs.

The global players of the aviation industry are shifting a growing shares of their value added to their subcontracters. New subcontractors must do considerable expenses to get accustomed to the special quality and security requirements of the aviation industry. This can be done as an EASA approved production organisation or as an extended workbench. The decision orientates itself at the specific activities required.

The article describes the quality inspection of micro cold formed components in the collaborative research center 747 “micro cold forming” at the University of Bremen. These components, e.g. small springs in cell phones, are manufactured with a speed of up to 300 parts per minute in a micro cold forming machine. Overall dimensions are below 1mm. These dimensions lie in a field between tactile measuring techniques of form and position and surface metrology, e.g. roughness. Yet a high inspection rate is impossible due to problems in production engineering and metrology. Therefore, fast optical metrology, new evaluation methods and quality control is needed to ensure an economical manufacturing process for micro cold formed parts.

Due to increasing product complexity, quality, timing and resource constraints, the management of product development projects becomes more and more challenging. Especially the determination of current product quality, an indicator for the actual development status, is hard to accomplish. For this reason, the article presents a concept for a real-time quality estimation for products and intermediate results. The concept is used and evaluated in the semiconductor industry.

The laboratory for machine tools WZL of RWTH Aachen University and Scheidt & Bachmann have jointly developed a methodology for product structure oriented continuous improvement of products and processes. The staff members’ manifold experience with complex products is used effectively by a combination of a product structure oriented assessment and a production portfolio oriented interpretation. Hence, experiences are quantified by the metric “additional effort of time per single use”. This additional effort addresses the coordination and correction expenses, which are typically not quantified and handled by variety-neutral surcharges in the calculation scheme. The methodology is working on the basis of “As-Is” data and not as usual on the basis of planning data like in conventional approaches of variant management. The factual composition of the products is used instead. By applying the methodology for several product families, latent optimization potential could be determined ...

Besides the product quality companies have now recognized the process quality as further potential for more economic efficiency within the production. Process-oriented measured values are required for CIP activities as well as for Six Sigma projects when it comes to the determination of improvement possibilities. A manufacturing execution system (MES) offers the information virtually at the push of a button. By means of this CIP activities and Six Sigma projects are accelerated and in addition more potential is discovered than without a systematic entry of the process influences by a MES.