Research On Product Disassembly In Remanufacturing

With the development of science and technology and the increase of the individualizedconsumption, all kinds of new products emerge in endlessly. A lot of products were quicklyeliminated due to their outdated function and the product life cycle is becoming shorter andshorter. At the same time, limited resources of the planet are dwindling and some resourcesare even exhausted in the process of industrialization. However, there is a greater demand forresources from human. In order to solve the contradiction between resource scarcity andserious waste produced by scrapped products, remanufacturing engineering arises at thehistoric moment which is a sustainable production way of development. Remanufacturingwhich accords with recycling economic principle is a kind of advanced production style andalso a kind of green manufacturing. It can give waste resources higher added value and is thebest form of recycling."Product dissembly" is the first step and a key issue in theremanufacturing process and a reasonably dissembly sequence can effectively decrease thecost and improve the efficiency of dissembly, reduce pollution, improve the reuse rate andimprove the efficiency of remanufacturing process. Therefore, the research on productdissembly has important theoretical and practical value.In view of the importance of product dissembly in remanufacturing, this paper selectsestablishing dissembly model and planning and optimizing dissembly sequence as researchobject. It borrows ideas from research findings of remanufacturing and disassembly both athome and abroad, starting from basic theories, elaborating the concept of circular economyand remanufacturing and also elaborating the remanufacturing process. By analyzing theremanufacturing process, it identifies the key problems in the process and detailedlydiscusses issues related to dissembling. On this basis, common dissembly models aresummarized and analyzed, which including graph model, matrix model and Petri Nets model.Based on the analysis of above models, a disassembly model based on polychromatic setstheory was presented on the basis of pre-existing disassembly models. According to thepolychromatic sets model of undirected graph, this paper sets up possible displacementmodel and possible displacement equation, plans dissembly sequence and constructshierarchical graph. Genetic algorithm is applied to optimiz dissembly sequence. Optimization process mainly considers two evaluation standards: dissembly toolstransformation and direction change. It establishes fitness function and takes the least time ofdissembling as optimization objective. In this paper, proportion selection, precedencepreservative crossover（PPX）and interchange mutation are designed and a detailedoptimization process is provided. At last, a case about machine vice’s dissembly was showedto demonstrate the feasibility of the model and algorithm.