بررسی انواع اتصال در طراحی برای جداسازی قطعات (DFD) با استفاده از فرایند تحلیل شبکه ای (ANP)
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|6014||2006||20 صفحه PDF||سفارش دهید||11718 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Computers & Industrial Engineering, Volume 50, Issues 1–2, May 2006, Pages 35–54
Design for disassembly (DFD) is an important design concept to make products more friendly for maintenance and remanufacturing practices. One of the important issues in DFD guidelines is related with the selection of the connectors used in the product. This paper evaluates the alternative connection types using the powerful analytic network process (ANP). The paper generates a complete ANP model, which includes all important aspects of connector selection. The model presented evaluates alternative connectors by including the three main concerns: (1) making product disassembly friendly; (2) making product assembly efficient; and (3) increasing the product performance when it is in-use. The results obtained from the model can benefit designers in making better decisions on selecting connectors to be used in the product. Benefits of the approach is detailed through illustrative example.
Disassembly is a systematic method for separating a product into its constituent parts, components, subassemblies, or other groupings for several reasons (Lambert & Gupta, 2005). One of the reasons for disassembly is to carry out maintenance-related activities. Either a simple product or a complicated machine may be disassembled partially for the purpose of repair or periodic maintenance. Until a decade ago, many people believed that this is the only purpose of disassembly. However, with the realization of environmental problems including the alarming rate of diminishing resources, the concept of product recovery has captured the attention of a lot of governments, companies, researchers as well as the general public (Gungor & Gupta, 1999). Product recovery (PR) aims to minimize the amount of waste sent to landfills by recovering components and materials from old or outdated products via remanufacturing and recycling (including reuse of parts and products). Recycling aims to recover the material content of retired products by performing the necessary disassembly, sorting, and chemical operations. On the other hand, remanufacturing preserves the product's (or the part's) identity and performs the required disassembly, sorting, refurbishing and assembly operations in order to bring the product to a desired level of quality. Disassembly has proven its role in PR by allowing selective separation of desired parts and materials. Disassembly may be partial (some subassemblies are not fully disassembled) or complete (the product is fully disassembled) depending on the objectives of the disassembly processes (Gungor & Gupta, 2002). Although complete disassembly has not yet been commonly practiced, the current tendency towards the PR will increase its use (Lambert & Gupta, 2005). Disassembly operations both in PR and maintenance are affected by the design stage of the product. The number of parts, the fastener elements used to create the product generates a huge impact on the efficiency of disassembly processes. Thus, designing for disassembly (DFD) is important and, therefore, it has been given a special attention (Fischetti, 1992, Inoue, 1994, Li et al., 1995, Lowe and Niku, 1995, Shyamsundar et al., 1998, Simon, 1991, Subramanian, 2004, Villalba et al., 2004 and Wittenburg, 1992). DFD initiatives lead to the correct identification of design specifications to minimize the complexity of the structure of the product by minimizing the number of parts, increasing the use of common materials and choosing the fastener and joint types which are easily removable. Connectors play a key role in determining the disassemblability of the product. A connector or a fastener is a component, which is utilized to hold the mated parts together in a product. The type of fastening method employed determines whether the product is to be disassembled using a destructive or a non-destructive disassembly approach. Therefore, the selection of fasteners become an important question in DFD. Although, destructive approaches such as cutting, breaking and tearing are popular disassembly applications, non-destructive approaches are favorable due to their ability in retrieving parts and materials at higher level of quality. In fact, if one wants to re-use a part from an old product it must be recovered unharmed; thus, non-destructive disassembly remains as a single option. Without any debate, non-destructive method is chosen to disassemble a product for the purpose of repair and maintenance. Non-destructive disassembly requires the use of connectors that are ‘easy’ to unfasten. This paper evaluates alternative connection types in design for disassembly (DFD) using an analytic approach. The approach employed is the analytic network process (ANP). ANP is used in many fields including environmentally related practices (Pochampally and Gupta, 2005 and Ravi et al., 2005). The evaluation of connection types deals with quantitative and qualitative measures. This is why the current work uses ANP, which is a strong analytical decision tool capable of including quantitative and qualitative criteria and their interdependencies into the evaluation process.
نتیجه گیری انگلیسی
This paper presented an ANP model for evaluating alternative connection types, which are used to join multiple parts in a product, from a DFD point of view. The paper evaluated the following connection types: discrete fasteners, integral attachments, adhesive bonding, energy bonding, and other connectors. The ANP model was developed to incorporate the design considerations related to the entire life-cycle of a product. In general, DFD guidelines deal with issues related to disassembly activities. The results obtained from the proposed model and its variants have demonstrated that DFD issues must consider all aspects of life-cycle of a product even if the objective is to design the product for disassembly. The models illustrated that eliminating certain stages of the life of a product may lead to different choices in the design stage. For example, from the models, it was obtained that when considering only disassembly, the discrete fasteners are considered to be the best connection type. However, once all considerations related to entire life cycle stages of a product were included in the model, the best connection type came out to be the integral attachments. The results obtained from the models help designers make better decisions on selecting connectors to be used in the product. The ANP structure proposed in the model may be revised and used to select a specific connector for a specific task. A designer can identify all part combinations in the product being designed and determine alternative connectors for each of the part combinations. For each of the part combinations, alternative connectors can be evaluated using an ANP model similar to the one proposed in the paper. At the end, priorities for connectors for each part combinations are gathered. Then, the designer can make his/her final decision on which connector to use in the product to make the product more disassembly oriented without ignoring other aspects of the life cycle. In order to demonstrate this, an example is presented in the paper. The example futher highlighted the power of using ANP approach to merge both qualitative and quantitative issues into making design related decisions.