Simulation of tyre retreading process ‐ an Indian case study

Tyre retreading is a process where used tyres are subjected to a sequence of value additive operations and are converted to reusable ones. Several benefits are associated with this process, like savings in cost, energy and reduction in environmental pollution. Collection of used tyres from the customers is characterised by the uncertainty in quantity, quality of used tyres, and timing of collection. The collected used tyres are subjected to two sets of operations, separated by a stage of inspection and subsequent rejection of tyres if found non‐retreadable. First set of operations remains unchanged irrespective of the condition of used tyres, whereas the work content of the second set varies with the condition of tyres. Some activities in retreading process are essentially manual in nature and the durations of manual activities are probabilistic, leading to formation of queue and delaying the subsequent stages. The aim of this paper is to analyse the whole system of retreading process, keeping in view the stochasticity in collection and processing, applying system simulation so as to help the decision maker plan for judicious manpower deployment, particularly for labour intensive operations.