Critical project planning and spare parts inventory management in shutdown maintenance

In the process industry, plant production is completely halted every so many years for large-scale maintenance comprising inspection, repair and overhaul. It paramount that this shutdown completed according to planning, which requires timely availability of replacement parts. setting, we present a spare parts optimization model algorithm includes cost-time trade-off precedence constraints between activities. The objective balance ordering cost expected project delay due waiting Using two-stage stochastic programming, policies are determined in first stage detailed schedule developed second stage. We propose sample average approximation with importance sampling pruning dominated activities solve problem, demonstrate method solves large instances quickly. also consider heuristics, e.g. standard management approach based on widely used critical path two heuristics draw from part inventory control literature. These give poor solutions.