S. Ramesh
Dr. N Arunkumar
Dr. R Vijayraj
Abstract
For batch type of manufacturing, machines and components are here grouped as machine cells and part families which can suit wide varieties of parts. The exceptional elements such as bottleneck machines and exceptional components arise in the formation can be processed simultaneously to get optimal solution. Machine cell formation and part family identification are carried out by fuzzy based similarity coefficient approach. The exceptional elements are solved by an integrated model of fuzzy cum optimization methodology and system approach. In first module, fuzzy and optimization models are used to solve exceptional machines and in second module, system approach is used to eliminate the exceptional components through either duplication of bottleneck machines or subcontracting the parts. A linear programming model is used to maximize the savings in machinery investments and material handling costs in the second phase. The machine cells and part families obtained in the fuzzy based approach are taken into consideration for their exceptional machines and components. The correlation between processing bottleneck machines and components is considered here to reduce inter and intra cellular movements, material handling costs and investments in machines. In fuzzy and optimization methodology, fuzzy methodology is used to give about duplication of machines in the respective machine cells and the optimization model can able to find the savings by significantly considering budgetary constraint of investment in mainly the bottleneck machines. System approach is used to give the decisions to be made between subcontracting the bottleneck parts or duplicating the bottleneck machines. Quantitative type fuzzy based similarity coefficient method can be able to solve small and medium size part families. The output of similarity coefficient method is given as block diagonal form which is having machine cells, part families clusters. Outcome of fuzzy cum optimization model and system approach is presented with discussion.
Keywords- Machine Cell, Part family, Exceptional Elements, Bottleneck machines, Exceptional components, Inter and Intra Cellular Movement, Material Handling Cost, Machine Duplication, Budgetary constraint.