Control point policy: part 1–efficiency within make-to-order environments

Abstract

The recognition of the desire for punctual delivery of products has lead to the use of the service level as a common performance criterion for measuring the proportion of products that meet due dates specified by the customer. To successfully increase the service level, a manufacturing system may respond more quickly to orders by reducing the levels of in-process inventory in the system and hence decrease throughput times. This paper examines the use of the recently developed Control Point Policy (CPP) in improving service levels in re-entrant, ‘make-to-order’ manufacturing systems and compares its effectiveness with that of the Critical Ratio scheduling rule. Simulation studies have been undertaken to provide insight into how and when to apply the CPP policy within such environments with results indicating that, in cases requiring small storage areas between machines, the CPP results in better service level performance.

Keywords:

• Simulation
• Takt time
• Lead time
• Scheduling
• Dispatching rules
• Kanbans
• CONWIP
• Performance measures
• Control Point Policy
• Blocking
• Fixed buffer
• Material flow
• Inter-arrival time
• Buffers

Acknowledgements

The authors wish to thank the UK's Engineering and Physical Science Council for sponsoring this research work through its Innovative Manufacturing Initiative (EPSRC Grant No. GR/M58818).