Analysing the critical design parameters for reuse

Reuse of components as opposed to material recovery, recycling or disposalhas been identified as one of the most efficient EOL strategies for products. Theconcept behind reuse is that some components and subassemblies have adesign life that exceeds the life of the product itself. In order for reuse to besuccessfully implemented as an EOL strategy, a designer needs to incorporateinto a product a philosophy of Design for Reuse (DfRe) at the early designstage. Reliable methods to assess the remaining life of used components basedon a products usage life are also required. Furthermore, current industrypractices and literature advocate that there is no methodology to decide whichparameters need to be redesigned so as to change the life of a selectedcomponent to a desired level.The objective of this research is to develop a methodology to assess the reusepotential of product groups based on component failure mechanisms and theirassociated critical lifetime prediction design parameters. Utilising theseclustered groups mathematical models were then developed to establish theuseful life of the components for each clustered group. Finally, a means ofequating useful life to design life was established and the relationship between,the failure mechanisms, critical lifetime prediction design parameters anddesign life were represented in graphical format.In order to achieve the proposed objective, Cluster analysis, in particular GroupTechnology (GT) and Hierarchical clustering were employed to groupcomponents with similar failure mechanisms. Following this, multiple linearregression was used to establish mathematical models based on conditionmonitoring data for each of the clustered groups and their related critical lifetimeprediction design parameters. A sensitivity analysis was conducted using themathematical models, in order to produce graphical relations between theuseful life and design parameters of a product.The validity of the suggested methodology was tested on electric motors and agearbox as both these components have demonstrated great reuse potential.The results demonstrate that the methodology can assist designers inestimating the design life and associated design parameters with greataccuracy, and subsequently aiding in a stratagem for reuse