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- GUNNARSDÓTTIR, SOFFÍA ARNÞRÚÐUR, 1987, et al.
(författare)
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Towards Simulation of Geometrical Effects of Laser Tempering of Boron Steel before Self-Pierce Riveting
- 2016
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Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271. ; 44, s. 304-309
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Konferensbidrag (refereegranskat)abstract
- The automotive industry is continuously developing and finding new ways to respond to the incremental demands of higher safety standards and lower environmental impact. As an answer to weight reduction of vehicles, the combination of boron steel and composite material is being developed along with their joining process, self-pierce riveting. Boron steel is an ultra-high strength material that needs to be locally softened before the joining process. However, the joining process deforms the part. This paper investigates factors affecting the geometrical deformation during the tempering process and lists important phenomena that need to be included when simulating the tempering process.
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| 2. |
- Wärmefjord, Kristina, 1976, et al.
(författare)
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Welding of non-nominal geometries : physical tests
- 2016
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Ingår i: Procedia CIRP. - : Elsevier BV. - 2212-8271 .- 2212-8271. ; 43, s. 136-141
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Tidskriftsartikel (refereegranskat)abstract
- The geometrical quality of a welded assembly is to some extent depending part positions before welding. Here, a design of experiment is set up in order to investigate this relation using physical tests in a controlled environment. Based on the experimental results it can be concluded that the influence of part position before welding is significant for geometrical deviation after welding. Furthermore, a working procedure for a completely virtual geometry assurance process for welded assemblies is outlined. In this process, part variations, assembly fixture variations and welding induced variations are important inputs when predicting the capability of the final assembly.
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| 3. |
- Lööf, Johan, 1979, et al.
(författare)
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Optimizing Locator Position to Maximize Robustness in Critical Product Dimensions
- 2010
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Ingår i: ASME 2009 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, IDETC/CIE2009; San Diego, CA; United States; 30 August 2009 through 2 September 2009. - 9780791848999 ; 2:PARTS A AND B, s. 515-522
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Konferensbidrag (refereegranskat)abstract
- The way parts are located in relation to each other or in fixtures is critical for how geometrical variation will propagate and cause variation in critical product dimensions. Therefore, more emphasis should be put on this activity in early design phases in order to avoid assembly and production problems later on. In earlier literature, locator positions have been defined using optimization to reach a robust locating scheme. This implies that the total robustness of a part is optimized by placing the locators in an optimal way. Sometimes there are areas on parts that are more sensitive to variation than others. Therefore, this paper suggests an approach for optimizing the positions of locators in a locating scheme to maximize robustness in defined critical dimensions. A formulation of an optimization problem is presented, and an algorithm solving this in a heuristic approach is developed. Finally, this algorithm is applied on an industrial example.
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| 4. |
- Wandebäck, Fredrik, et al.
(författare)
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Variation Feedback and 3D Visualization of Geometrical Inspection Data
- 2010
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Ingår i: Proceedings of the ASME 2009 International Design Engineering Technical Conferences & Computers and Information in Engineering Conference IDETC/CIE, August 30 - September 2, 2009, San Diego, California, USA. - 9780791849057 ; 8, s. 197-208
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Konferensbidrag (refereegranskat)abstract
- There is no type of manufacturing process that is not afflicted by variation. Activities intended to ensure the quality of a company's geometry processes are usually referred to as geometry assurance activities. One clear industrial problem is to understand the relations between the products concept and the manufacturing process. Dimensional data is a very important source of experience of how a product's geometry has worked in the interaction with the actual manufacturing system. Users therefore need good analysis and presentation tools of geometry outcomes to support both the product developers and production engineers in the analysis of the production output and its consequences. Today the dimensional data can be difficult to obtain or access, and is not necessarily presented in such a way as to provide the user with all necessary information. This paper presents how presentation and analysis tools of geometrical inspection data can be taken a step further. New functionality for feature based 3D visualization of inspection data has been developed which integrates the variation simulation platform and the inspection data database. The goal has been to create better tools for analysis of geometrical variation and increase the understanding of the sources of variation.
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| 9. |
- Forslund, Anders, 1982, et al.
(författare)
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Minimizing weld variation effects using permutation genetic algorithms and virtual locator trimming
- 2018
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Ingår i: Journal of Computing and Information Science in Engineering. - : ASME International. - 1530-9827 .- 1944-7078. ; 18:4
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Tidskriftsartikel (refereegranskat)abstract
- The mass production paradigm strives for uniformity, and for assembly operations to be identical for each individual product. To accommodate geometric variation between individual parts, tolerances are introduced into the design. However, this method can yield suboptimal quality. In welded assemblies, geometric variation in ingoing parts can significantly impair quality. When parts misalign in interfaces, excessive clamping force must be applied, resulting in additional residual stresses in the welded assemblies. This problem may not always be cost-effective to address simply by tightening tolerances. Therefore, under new paradigm of mass customization, the manufacturing approach can be adapted on an individual level. This paper focuses on two specific mass customization techniques: permutation genetic algorithms (GA) and virtual locator trimming. Based on these techniques, a six-step method is proposed, aimed at minimizing the effects of geometric variation. The six steps are nominal reference point optimization, permutation GA configuration optimization, virtual locator trimming, clamping, welding simulation, and fatigue life evaluation. A case study is presented, which focuses on the selective assembly process of a turbine rear structure of a commercial turbofan engine, where 11 nominally identical parts are welded into a ring. Using this simulation approach, the effects of using permutation GAs and virtual locator trimming to reduce variation are evaluated. The results show that both methods significantly reduce seam variation. However, virtual locator trimming is far more effective in the test case presented, since it virtually eliminates seam variation. These results underscore the potential of virtual trimming and GAs in manufacturing, as a means both to reduce cost and increase functional quality.
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