| With the rapid development of the number of the vehicle, the nubmber of the end-of-life vehicles is also rising fast. On the one hand, end-of-life vehicles contain a large number of renewable resources, if not effectively recycled, it will be a great waste of resources; On the other hand, it contains a variety of end-of-life vehicle heavy metals, chemical substances, such as, liquid and plastic. If they are dealed with unproperly, they will cause serious pollution to the environment. Recycling of end-of-life vehicles not only can generate considerable economic benefits, but also can benefit the sustainable development of the entire auto industry.Autombile disassembly is defined as "the prcocess of systematic removal of desriable cosnstiute parts from an assembly whlile ensuring that there is no impairment of the parts due to the process". Disassemble is the prerequisite for efficient recycling, only in this way, can we achieve high purity of material recycling, and realize the probably reuse of parts. Disassemble of automotive products is an important part of recycling, it can resolve the recycling and reuse issue of end-of-life vehicles, and as a result, it ease the shortage of resources and reduce waste on the environment caused by end-of-life vehicles. Two methods are generally used to remove components or materials: destructive and non-destructive disassembly. The most common methods for destructive disassembly are shredding processes. Shredding processes could be damege the potential re-use parts, meanwhile, shredding processes also result in hybrid materials which is not conducive to the recovery of high purity materials. Therefore, the current research of the question of dismantling mainly focuses on the study of non-destructive disassembly.Tradtionally, products products are designed mainly to meet functional requirements. Therefore, recycling and environmental issues are rarely considered during the design process. Most companies do not consider methods of retiring EOL products and their impact on the environment. Design for disassembly has become an important issue due to growing concerns about the environment and the shortage of natural resources. Design for disassembly is one of the main contents of the green design. It demands that disassembly is the one of the major goal during at the initial stage of product design. Therefore, it can make our designed product more good manufacturing processes and maintenance, and also be easy to dismantle to recover and resue EOL products, and as a result, can save natural resources and prevent environmental pollution.The dismantling of product is a random complex issues, which includes a series of problems, such as, "can or not dismantling", "should or not dismantling" and "how to dismantling ". "Can or not dismantling " is the question that the components of whether or not removable, that is also the question of the station of parts, which is closely related with not only the internal factors, such as the number of assembly components, species, linking the relationship but also the external factors, for example the environment in which the parts work. It has a strong uncertainty character, which is the most difficult question to solve in the analysis of dismantling. The question "should or not dismantling" is in accordance with the working station and value information of the assembly which will been dismantled, which provides a comprehensive evaluation of the end-of-life products to solve the decision-making question of the product shoud or not been dismantled. The question of "how to dismantling" is solved to how to remove the produce and components effectively, but which must on the basis of the solve of the question of "can or not dismantling" and "should or not dismantling". It includes disassembly sequence generation and planning ect a series of problems. Therefore, only "can or not dismantling", "should or not dismantling" and "how to dismantling"ect the dismantling question are clear understanded, the nature of dismantling can been exactly comprehended, which provides theoretical guidance for making rational disassemblability evaluation methods and dismantling practical guidance of the design of disassemblability.Disassembly is a basic sector in the utilization of renewable of automobile. It considered that whether the ELVs(end of life vehicles) are easier to be disassembled and recycled when design them, so that we can save the cost of the recycle, increase the rate of the ELVs reuse and reduce the harm of the disassemble work to the environment. Product cocurrent design requires disassembly design and analysis technology. In this dissertation, the basic theory of automobile disassembly, model of disassembly information, gain the disassemble information, generation method and optimization of disassemble sequences, evaluate the disassemblability of automobile are deeply and systematic researched based on the research related domestic and foreign. The main contects are as follows: 1) The purpose and significance of DFD are introduced. To begin with, DFD can save natural resources and reduce environmental pollution study, what is more, it is conducive to the development of the auto industry, even the entire manufacturing. In addition, the systemic structure of design for disassembly is presented and the study status of guideline of DFD, disassembly sequence generation and planning and evaluation of the dismantlbility also are introduced.2) Removal and dismantling/disassembly are differentiated which are confused by many researchers, whose concepts and relevant definitions are given. Therefore the new disassembly study idea which must be on the basis of the study of removal is put forward. On the basis of the proposed relevant index of dismantling and the issue of dismantling randomness, the index of evaluation of the dismantlbility is carried out the mathematical expression by the use of probability theory. The relationship between them is reasoned and proofed by strict mathematics. A deconvolution algorithm is used when the vehicle products are descridbed. In addition, in conjunction with the actual situation of the dismantling issue, the sub-convolution method is taken to address the difficulty of calculation. It provided the theoretic method for the evaluation of the disassembly issue.3) The disassembly information is analysed on detail. Take the crank connecting rod mechanism and the clutch diaphragm spring as an example, a great number of dismanting models are presented, such as, the undirected graph, the directed graph, AND/OR graph and so on. The hybrid model is put forward after the advantages and disadvantages of various models were compared. Take the alternator as an example, a new hybrid model is builded.4) The work of the extraction of information is carryed out based on the UG structure model. One of the most important contents is that the extraction of information based on the use of UG secondary development. The system environment settings of UG secondary development and the structure of assemble are analyzed. The information including the disk of history of parts, the information of the layer, the information of the mate and the information of solid limit, are extracted base on the extraction. Storage methods of the graph are summed up, such as, adjacency matrix, adjacency table, cross linked and adjacent multi-table method and so on. In addition, their high-level language description and application circumstance also are summed up. Take the crankshaft connecting rod mechanism as an example, its hybrid model is achieved by the use of VC++. Therefore, it has laid a foundation for disassembly relevant analysis and evaluation. 5) The complete disassembly sequence and target disassembly sequence are generated based on the constraint matrix and the hybrid model. Dismantling planning, which carry out the optimization process or sequence puts the most efficient, lowest cost, dismantling the shortest time, energy consumption and pollution at least as the target. Based on the randomicity of removal time, the disassembly probability planning method is put forward on the disassembly sequence. As a result, it can more clearly and accurately program the process of the actual dismantling products through the introduction of two parameters of removal time and dismantlbility degree.6) Factors which influence the dismantlbility of automobile products are analyzed and the several common automotive connection means also are analyzed. The dismantlbility evaluation system is established based on it. In addition, the quantitative index also is analyzed. At last, the screw thread connection experimentation is carryed out and its time distribution is obtained. It combined with deconvolution algorithm, the disassembly of the generator is analyzed and the probability of product disassembly also is obtained under the different time. It provides a useful reference for the dismantlbility evaluation.In short, this paper put forward the new method of disassemability evaluation based on the randomicity of removal time and bring forward disassembly study new idear that disassembly research must be on the basis of the further study of the removal. We hope it provides a guiding role to make the dismantling research developed in the microcosmic direction.
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