Evaluation of Unreliable Flow Lines with Limited Buffer Capacities and Spare Part Provisioning

F. E. Sachs, S. Helber, G. P. Kiesmüller

Research output: Contribution to journalArticlepeer-review

3 Scopus citations


We consider a model of an N-stage flow line with stochastic processing times and interstage buffers that decouple adjacent production stages. Machine downtimes are induced by failures of critical machine components. Each machine is assumed to have exactly one of these failure-prone components. To achieve high machine availability, it is assumed that spare parts for those failure-prone critical components are kept in stock. Failed components are immediately replaced with new, functioning components, and a one-for-one replenishment policy is applied for the restocking of those spare parts. We present a novel decomposition approach to approximate the average throughput and inventory for a system with an arbitrary number of machines, buffers, and spare parts. With a detailed numerical study, we analyze the impact of different parameter constellations on the approximation quality. We demonstrate the remarkable accuracy of our method by comparing our results with both exact and simulated values. Using our method, we further study the complex interaction and partial substitution effects between buffer sizes and spare part base-stock levels on the logistical performance of the flow line.

Original languageEnglish
Pages (from-to)544-559
Number of pages16
JournalEuropean Journal of Operational Research
Issue number2
StatePublished - 16 Oct 2022
Externally publishedYes


  • Decomposition
  • Manufacturing
  • Markov processes
  • Spare parts
  • Stochastic flow lines


Dive into the research topics of 'Evaluation of Unreliable Flow Lines with Limited Buffer Capacities and Spare Part Provisioning'. Together they form a unique fingerprint.

Cite this