SUPPLY CHAIN MANAGEMENT AND SPARE PARTS ISSUES IN IRANIAN RAILWAY INDUSTRY: IMPLICATIONS FOR EQUIPMENT MAINTENANCE

Efficient supply chain management (SCM) is critical for maintaining equipment reliability in the railway industry, particularly in managing spare parts logistics. This study investigates SCM and spare parts challenges in the Iranian railway industry, a sector vital to the country’s transportation infrastructure yet plagued by inefficiencies, sanctions-induced procurement delays, and aging rolling stock. Using a mixed-method approach—combining quantitative data from Iranian railway performance metrics (2015–2023) and qualitative insights from semi-structured interviews with industry experts—this paper identifies key issues: prolonged lead times, inventory mismatches, and inadequate supplier coordination. Two novel frameworks are proposed: a Spare Parts Availability Index (SPAI) and a Maintenance-Supply Chain Integration Model (MSCIM). Findings reveal that spare parts shortages contribute to 35% of equipment downtime, costing an estimated $50 million annually. Implications suggest adopting digital SCM tools and localized spare parts production to enhance maintenance efficiency. This research offers original contributions to railway SCM literature, particularly in sanction-affected contexts.