Time-Limited Next Arrival heuristic for batch processing and setup reduction in a re-entrant environment

This paper presents a new batch scheduling heuristic - the time-limited next arrival heuristic for batch processing and setup reduction (TLNA). This heuristic has been defined for a batch processing machine group in a re-entrant manufacturing environment where setups are sequence-dependent. When making the scheduling decision, TLNA takes into account future arrivals based on a user-defined wait time. A series of experiments is conducted on a discrete event simulation model to determine the impact of this wait time. A total cost function is used to combine two conflicting performance measures (total item queuing time and total machine running time) into one. All TLNA wait time scenarios are compared to the next arrival control heuristic for multiple products and multiple machines (NACHMM). The experiments presented show that there is a wait time that minimises the total operational cost. TLNA outperforms NACHMM with regard to all performance measures except total queuing time.