Thesis (M.Eng.) - Asian Institute of Technology, 1997

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Advanced Technologies

In this study, the effect of Component Commonality on the different phases of a manufacturing system is discussed. The manufacturing system considered is an Assemble-toOrder (ATO) one. Two-end-products each having a two level product structure is assumed for the analysis. Different models considering varying levels of commonality have been developed for the study and different analytical tools (both deterministic and stochastic) have been used for investigating the models. The phases, specially Production and Component Inventory, have initially been treated individually as single stage systems for studying the effects of commonality on them. For each phase, effects on the relevant performance measures have been seen and efforts have been made to develop mathematical models to evaluate some threshold value in terms of suitable variables to predict an applicable range of commonality. Special consideration have been given to the effects of learning and forgetting on total processing time in presence of commonality. Similar analysis 'have also been made for a multistage system considering all the phases together. For the multi-stage system the effects of commonality on total costs of the system (taken in terms of inventory cost) is seen and a threshold value of common component cost have been evaluated to help in decision making regarding the introduction of commonality. The effects of commonality on the performance measure of the production phase of a multi-machine case has also been repo1ied.