Fraunhofer-Institut für Produktionsanlagen und Konstruktionstechnik IPK
Now showing 1 - 4 of 4
PublicationDisassembly factories for recovery of resources in product and material cycles( 1996)
;Seliger, G. ;Hentschel, C.Wagner, M.The worldwide increase of waste and restricted resources require the recycling of worn-out products. Disassembly of complex consumer products offers advantages to other recycling technologies, like material recovery and reuse of components. Current disassembly processes, however, can not cope with the increasing amount and variety of products that have to be discarded each year. The multifarious aspects of disassembly factories are addressed in an integrated project by an interdisciplinary research team at the Technical University Berlin. The closely correlated study fields are disassembly processes and tools, logistics and urban planning, product evaluation and disassembly planning as well as design for disassembly. An outline of the research program is given and the guiding theses are presented. Two example illustrate the range of the research activities. In a bottom-up approach fundamental knowledge about disassembly processes is acquired and used for the design of new tools. With t he strategy of creating new acting surfaces disassembly tools become independent of shape variations and additional changes to the products during usage. The topdown approach provides methods for the planning of disassembly factories. Grouping of product variants is used to support the design of disassembly systems. To cope with the uncertainties due to usage influences on the product, fuzzy set theory is applied for planning purposes.
PublicationDisassembly process planning to support the recyclability of used technical products( 1994)
;Seliger, G.Hentschel, C.Due to its complexity, amount and variety, scrap from used complex products constitutes a major recycling problem in the industrialised countries. Advanced recycling technologies currently exist only for pure materials. Disassembly fills the gap between scrap from complex products and recycling of pure materials; even more, it allows the reuse of subassemblies and components. In this paper, difficulties in planning disassembly steps are depicted, structured, and illustrated using the example of picture tubes from used monitors.
PublicationIntegration of recycling considerations into product design - a system approach( 1994)
;Seliger, G. ;Zussmann, E.Kriwet, A.This paper presents an integrative approach for design-for-recycling of products. A system approach is suggested integrating the products recycling feautres, the recycling process and the product logistic support during the products life cycle. Design-for-recycling is defined as a design for ease of product and maximum output. Rules dedicated for design-for-recycling are given particularly to the disassembly process of a product during the recycling stage. The design approach is demonstrated by investigating a washing machine as a representative of a "white" household machines family. The recyclability of the machine is evaluated, where different design-forrecycling rules are applied in order to improve the machine recycling characteristics.
PublicationDesign for disassembly in the framework of life-cycle-design( 1993)
;Seliger, G. ;Hentschel, C.Kriwet, A.Recycling technical consumer products after usage is a subject of rising importance. The lack of natural ressources, the necessity to save energy and the reduced permission for landfill areas or burning facilities (reflected in the steeply rising cost for waste disposal) have increased the awareness that components and/or materials of used products have to be regained and reused. Current recycling technologies (shredding / milling) allow an almost complete automatic regaining of ferrous metals, whereas nonferrous metals usually have to be sorted out by hand. The rising fraction of plastic materials, rubber, glass and textiles can not be regained and has to be deposited. Disassembly of the product prior to shredding allows to increase the share of materials to be regained for further use. Furthermore, ease of disassembly is also an important factor for reducing maintanance and repair costs. In order to minimize disassembly costs, the ease of disassembly has to be considered during the d esign process. However, design for disassembly is only one factor amongst many in the scope of Life Cycle Design (LCD). In order to weigh its importance, common evaluation criteria and a common measuring unit is needed for all "costs" and "benefits" during all stages of the Life Cycle.