Papers by Keyword: Quality Assurance

Abstract: Construction and demolition waste (CDW) accounted for almost 36% of total waste produced in the European Union in 2018. Growing recovery rates are achieved but mainly for low-value applications. Variable composition and characteristics undermine customers’ confidence who prefers primary materials with certified properties and at more competitive value/cost. Zero energy and waste targets are driving to rethink the waste value chain, necessitating a search for new technologies to reduce carbon emissions and waste volumes towards a more efficient and circular system. This paper presents an outline of the approaches to enhance CDW management that will be developed in the newly funded Horizon Europe project RECONMATIC. This project will develop digital and automated solutions to support advanced CDW management towards zero targets and will explore applications of technologies at different phases of the asset whole life cycle. Technical issues will be considered in aspects such as material segregation, pre-demolition audits, selective deconstruction, waste traceability procedures, as well as broader economical-societal issues such as business model, health & safety, sustainability, and technology readiness level. RECONMATIC aims to usher a paradigm change in CDW management by helping the construction industry taking a step change in circular economy development.

Abstract: The Automotive Industry is in constant evolution, thanks in part to its high level of production and customer demands for quality assurance. New processes, equipment and products are constantly emerging, leading to new vehicles launched to the public. These processes and equipment need adequate monitoring tools and forms of quality assurance, and it is the responsibility of the engineering department to look for economically viable and efficient ways of guaranteeing the quality of products in an industry where quality itself is considered one of its pillars. This work aims to develop and validate a solution for quality control in the automotive industry while taking full advantage of the technological factors provided by the equipment used. It deals with researching and applying a three-dimensions (3D) scanner in product quality monitoring tasks of a door panel manufacturing process. Pilot studies were carried out to assess the real capabilities of the equipment and determine problems that could arise when scaling the process for a real production of car door panels. The implementation and final results are also described in this work, showing that it is possible to develop a flexible equipment with multiple applications and apply it in the automotive industry.

Abstract: Fiber reinforced plastics are an essential material for lightweight products. However, their superior mechanical properties compared to traditional materials are only guaranteed, if necessary quality requirements are met (e.g. fiber orientation). One promising approach for detecting quality deviations in image-based monitoring data is to use deep learning models. Nevertheless, these models need vast amounts of labeled training data, which is either not available or expensive to attain. To train deep learning models more data efficiently, a common and intuitive transfer learning approach is applied to detect fiber orientations for two different fiber reinforced plastics. By comparing the similarity between different domains of public datasets with the domain of the materials of this work, the range of optimal hyperparameters were estimated for the transfer learning task at hand. Through a grid search within the estimated hyperparameter range, the best-performing models were identified, showing that models transferred from similar domains do not only result in better performance but are also more robust against data scarcity. Finally, the results show that transfer learning holds the potential to accelerate the usage of deep learning for quality assurance tasks in textile-based manufacturing.

Abstract: The 3-roll Reducing and Sizing block RSB has been known as reliable instrument for the economic production of SBQ and wire rod. By continuous development of the RSB technology in the past decades, KOCKS clearly contributed to meet high availability, efficient production, fast dimension change and tightest tolerances to secure a rolling mills’ existence. The repeatability of tightest tolerances is an enormous challenge due to the constantly changing basic conditions of a mill. The operator needs to precisely adapt the process parameters reacting to smaller lot sizes made of different material grades with partly strongly varying spreading and shrinkage behavior or yield strengths. It is KOCKS' objective to meet this challenge by an automated tool, the Size Control Systems SCS^®, thus lifting the quality assurance of long products to a new level.

Abstract: Dimensional measurement is a key process in the quality assurance of manufacturing. Not only classical one-dimensional measurement devices, several kind of three-dimensional coordinate measuring systems (CMSs) including coordinate measuring machines (CMMs) are used for dimensional measurement tasks in measurement rooms or in factory floors. For the purpose of the quality guarantee, the measurement for the validation on the products should be performed with the traceable manner. In the case of the dimensional measurement, the measurement results of the products should be stated as the corresponding values in the reference temperature, 20 °C. Therefore, at least the traceability of the length indication instruments and temperature-measuring equipment installed into the measuring device to be used should be ensured. Usually, the traceability of the instrument or equipment is ensured through the calibration on it. Now, typical CMMs in factory floor have non-calibrated temperature-measuring equipment because the equipment is hard to be detached off for the calibration, and therefore, the temperature-measuring equipment is usually left uncalibrated. Recently, a new procedure by which both the length indication instruments and temperature-measuring equipment installed into a CMM are able to be calibrated simultaneously is established. In this research, the traceable dimensional measurement using a CMM equipped with uncalibrated temperature-measuring instrument is developed by as an application of the established calibration procedure. Through the experiment, the traceable dimensional measurement using the CMM placed on the factory floor is demonstrated.

Abstract: Nowadays the flexibility and specific cost of manufacturing have a relevant role in the competitiveness of the companies. In our opinion the most important objective of Industry 4.0 is the realization of intermittent manufacturing at mass production’s productivity and specific cost. This aim can be only reached by creating more complex manufacturing systems. The increase in manufacturing complexity results in new challenges in the quality assurance of manufacturing processes. We can collect new types of data that enable the improvement of product and process service quality. This paper introduces the essence of Industry 4.0, as well as the new challenges for the quality assurance of manufacturing processes. Possible research directions for overcoming challenges are also presented.

Abstract: A new method for a fast analysis of heavily deformed, multicomponent ferritic/pearlitic steels microstructure based on XRD measurements had been developed. Its practical application has been examined and proven during wire rod production of a high-strength eutectoid non-alloyed steel grade containing 0.81 weight percent carbon. For individual technological conditions, the lattice strains and their anisotropy were analysed quantitatively by means of fast X-ray diffraction measurements and correlated with the results of comprehensive mechanical testing. Obtained relationships between the microstructure characteristics and mechanical properties were described using physically based models and used to establish a material specific database for prediction of the mechanical properties from X-ray diffraction data. Depending on the deformation state different parameters have to be applied for the material’s macroscopic properties prediction. Additionally, the fast microstructure analysis can provide more detailed information in the case of deviations from the as-required material’s properties due to technological aberrations.

Abstract: The durability of concrete structures in severe environments is not only related to design and materials but also to construction. Thus, much of the observed durability problems can be ascribed due to lack of proper quality control and quality assurance during concrete construction resulting in poorly achieved construction quality. Upon completion of new concrete structures, the achieved construction quality typically shows a high scatter and variability, and during operation of the structures, any weaknesses and deficiencies will soon be revealed whatever durability specifications and materials have been applied. To a certain extent, a probability approach to the durability design can accommodate the high scatter and variability. However, a numerical approach alone is insufficient for ensuring the durability; greater control and improvements in durability also require the specification of performance-based durability requirements which can be verified and controlled during concrete construction in order to achieve quality assurance. For new major concrete infrastructure, documentation of achieved construction quality and compliance to the durability specification should be essential parts of any rational approach to controlling and increasing the durability. In the present paper, a case study is presented which provides comparisons of work performed under performance and prescriptive durability specifications.

Abstract: The mechanical systems consist of assembled parts, between which diverse interactions take place. Tolerance analysis purpose is to study the effects of part geometric deviations on assembly functional requirements. In the current approaches from this field, the part geometrical deviations are toleranced without considering the evolution of the geometrical deviations during product exploitation. As consequence, between two parts identical as type but with different values of their geometrical features, inside the designed tolerance zones, any difference is made despite they might have significantly different life cycles or manufacturing costs. This paper presents a new conceptual approach concerning parts tolerance design, based on a new criterion, namely the dimensional quality, defined by two important features: life cycle and manufacturing cost. The main issue of this approach is the optimal relation between the manufacturing tolerance zones and the acceptable functional deviation domain. The new concept implementation is sampled in the case of an articulated arm.

Abstract: The aim of the study is the functional analysis of management system for laboratory tests in control of the manufacturing process, based on standard functionality of the SAP R/3 as an example of ERP systems.