A Supplier Selection Model in order to Increasing Productivity (Case study: One of the Active firms in Manufacturing of Refinery Equipment)

Supplier selection issue is one on the basic problem in all of industries especially in oil industry. In such issues¡ multiple criteria and sometimes contradictory criteria must be considered. So¡ these problems are considered as multi-criteria problems. Suppliers can have a huge impact on the performance of companies in different categories like¡ price¡ quality and delivery. Experts believe that there is not the best way for evaluating and selection and there are different methods in this field. In this study¡ first¡ with investigating other studies and interviews with experts and the basic criterias for supplier selection were identified and prioritized with Analytic Hierarchy Process. In the next step¡ according to the criteria and alternatives (suppliers)¡ a hierarchical analysis model prepared and alternatives were also prioritized. In order to determine economic order quantity for one of the main needed parts¡ a hybrid goal programing and analytic hierarchy process has presented and by using real data¡ model run and the optimum order for the part was determined for each supplier.