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Design for Producibility in Fabricated Aerospace Components

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Design for Producibility in Fabricated Aerospace Components THESIS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY Design for Producibility in Fabricated Aerospace Components A framework for predicting and controlling geometrical variation and weld quality defects during multidisciplinary design JULIA MADRID Department of Industrial and Materials Science CHALMERS UNIVERSITY OF TECHNOLOGY Gothenburg, Sweden 2020 Design for Manufacturing and Producibility in Fabricated Aerospace Components JULIA MADRID © JULIA MADRID, 2020 ISBN: 978-91-7905-384-0 Series number: 4851 ISSN 0346-718X Department of Industrial and Materials Science Chalmers University of Technology SE-412 96 Gothenburg Sweden Telephone + 46 (0)31-772 1000 [email protected] Cover: The cover illustration is a representation of producibility. Producibility arises from the interaction of two systems design and manufacturing Producibility becomes tangible in form of manufacturing variation and quality defects Printed by Chalmers Reproservice Gothenburg, Sweden 2020 A mi corazón ii iii Abstract In the aerospace industry, weight reduction has been one of the key factors in making aircraft more fuel efficient in order to satisfy environmental demands and increase competitiveness. One strategy adopted by aircraft component suppliers to reduce weight has been fabrication, in which small cast or forged parts are welded together into a final shape. Fabrication increases design freedom due to the possibility of configuring several materials and geometries, which broadens out the design space and allows multioptimization in product weight, performance quality and cost. However, with fabrication, the number of assembly steps and the complexity of the manufacturing process have increased. The use of welding has brought to the forefront important producibility problems related to geometrical variation and weld quality. The goal of this research is to analyze the current situation in industry and academia and propose methods and tools within Engineering Design and Quality Engineering to solve producibility problems involving welded high performance integrated components. The research group “Geometry Assurance and Robust Design” at Chalmers University of Technology, in which this thesis has been produced, has the objective to simulate and foresee geometrical quality problems during the early phases of the product realization process to allow the development of robust concepts and the optimization of tolerances, thus solving producibility problems. Virtual manufacturing is a key within the multidisciplinary design process of aerospace components, in which automated processes analyze broad sets of design variants to trade-off requirements among various disciplines. However, as studied in this thesis, existing methods and tools to analyze producibility do not cover all aspects that define the quality of welded structures. Furthermore, to this day, not all phenomena related to welding can be virtually modelled. Understanding causes and effects still relies on expert judgements and physical experimentation to a great deal. However, when it comes to assessing the capability of many geometrical variants, such an effort might be costly. This deficiency indicates the need for virtual assessment methods and systematic experimentation to analyze the producibility of the design variants and produce process capability data that can be reused in future projects. To fulfill that need, this thesis provides support to designers in assessing producibility by virtually and rapidly predicting the welding quality of a large number of product design variants during the multidisciplinary design space process of fabricated aerospace components. The first step has been to map the fabrication process during which producibility problems might potentially occur. The producibility conceptual model has been proposed to represent the fabrication process in order to understand how variation is originated and propagated. With this representation at hand, a number of methods have been developed and employed to provide support to: 1) Identify and 2) Measure what affects producibility; 3) Analyze the effect of the interaction between factors that affect producibility and 4)Predict producibility. These activities and methods constitute the core of the proposed Design for Producibility framework. This framework combines specialized information about welding problems (know- hows), and inspection, testing and simulation data to systematically predict and evaluate the welding producibility of a set of product design variants. Through this thesis, producibility evaluations are no longer limited to a single geometry and the study of the process parameter window. Instead, a set of geometrical variants within the design space can be analyzed. The results can be used to perform optimization and evaluate trade-offs among different disciplines during design space exploration and analysis, thus supporting the multidisciplinary design process of fabricated (welded) aerospace components. Keywords: Design for Producibility, Variation Management, Quality Assurance, Welding, Aerospace i ii Acknowledgments The research presented in this thesis has been carried out at the Department of Industrial and Materials Science (IMS) at Chalmers University of Technology in Gothenburg and at GKN Aerospace in Trollhättan, Sweden. It has received financial support from the Swedish Governmental Agency for Innovation Systems (VINNOVA) and the Swedish National Aeronautics Research Programme (NFFP) through the Wingquist Laboratory. I gratefully acknowledge their financial support. Concerning the arduous process of obtaining the PhD degree, I would first like to thank my main supervisor, Professor Rikard Söderberg, and my assistant supervisor, Associate Professor Kristina Wärmefjord. Your valuable feedback and support during the difficult moments have made it possible for me to achieve my goal. Thank you, Rikard, for your understanding and for getting the best out of me. Thank you, Kristina, for bringing calm to my tempestuous moments. Thanks to both for your patience and for your belief in me. Further, I wish to express my deepest gratitude to my two industrial supervisors, Johan Vallhagen and Johan Lööf. J. Vallhagen, your support during the first years, the most difficult ones, has been crucial to me. J. Lööf thank you for providing on-site support in these final years. Second, I would like to thank my co-authors and some of my colleagues for their comments and our great discussions which have greatly enhanced my research work: Samuel Lorin, Lars Lindkvist, Petter Andersson (GKN), Donatas Kveselys (GKN), Petter Hammerberg, Anders Forslund, Steven Hoffensson, Jonas Landahl, Konstantinos Stylidis, Ola Isaksson, Lars Ola Bligård, and Cecilia Berlin. I am also very grateful to everybody at GKN Aerospace who has helped me out during all these years. To all of you, thanks for your time and expertise. I feel I am part of your big GKN family. Concerning bringing this thesis to its final form, I want to acknowledge Gunilla Ramell for her excellent language editing. My personal thank you also goes to the Chalmers family. A warm thanks to everyone else at IMS and especially the 5th floor for making it such a pleasure to come to work every single day. In particular, I will miss the “small kitchen” lunches and people, as well as getting the perfect help from Lillvor. Furthermore, I would like to make special mention of my former colleagues Daniel and Marcel who showed me the way. Finally, I wish to acknowledge my parents, my friends outside work and specially my new little family, my partner Markus and my son Oscar. Thank you for your constant and unconditional support. Without that support, I could not have come this far. Sincerely, Julia Madrid Gothenburg, Sweden, June 2020 iii iv Appended Publications Paper A Vallhagen, J., Madrid, J., Söderberg, R., Wärmefjord, K., 2013. An approach for producibility and DFM-methodology in aerospace engine component development. 2nd International Through-life Engineering Services Conference. Procedia CIRP, 11, pp.151-156. Cranfield University, Cranfield, UK. Paper B Madrid, J., Vallhagen, J., Söderberg, R. and Wärmefjord, K., 2016. Enabling reuse of inspection data to support robust design: a case in the aerospace industry. 14th CIRP Conference on Computer Aided Tolerancing (CAT). Procedia CIRP, 43, pp.41-46. Göteborg, Sweden. Paper C Madrid, J., Söderberg, R., Vallhagen, J. and Wärmefjord, K., 2016. Development of a conceptual framework to assess producibility for fabricated aerospace components. 48th CIRP Conference on Manufacturing Systems - CMS 2015. Procedia CIRP, 41, pp.681-686. Ischia, Naples, Italy. Paper D Madrid, J., Forslund, A., Söderberg, R., Wärmefjord, K., Hoffenson, S., Vallhagen, J. and Andersson, P., 2017. A Welding Capability Assessment Method (WCAM) to support multidisciplinary design of aircraft structures. International Journal on Interactive Design and Manufacturing (IJIDeM), pp.1-19. https://doi.org/10.1007/s12008-017-0429-5 Paper E Madrid, J., Lorin, S., Söderberg, R., Hammersberg, P., Wärmefjord, K., & Lööf, J. 2019. A virtual design of experiments method to evaluate the effect of design and welding parameters on weld quality in aerospace applications. MDPI Journal Aerospace, 6(6), 74. https://doi.org/10.3390/aerospace6060074 Paper F Madrid, J., Landahl, J., Söderberg, R., Johannesson, H. and Lööf, J., 2018, Mitigating risk of producibility failures in platform concept development. 31st Congress of the International Council of the Aeronautical Sciences, (pp.
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