Reduce cycle time and work in process in a medical device factory : scheduling policies for needle assembly machine

Many manufacturing firms have improved their operations by implementing a work-in-process (WIP) limiting control strategy. This project explores the application of this concept to limit WIP and reduce cycle time for the Becton, Dickinson and Company's manufacturing facility in Tuas, Singapore. BD's Eclipse Safety Needle production line is facing increasing pressure to reduce its high WIP and long cycle times. With the forecast of increasing demand, the current production control practice will sooner or later push the shop floor space to a limit. We divided the overall system into three manageable sub-systems and analyzed different strategies for each. At Needle Assembly machine (AN) and downstream, we can achieve significant reduction in cycle time and work in process by eliminating the unnecessary early start of production and extra delay caused by the current planning method, and by reducing the transfer batch sizes. In this paper, we refine further these approaches to AN and packaging machines with consideration of a mixed dispatching rule and a CONWIP release rule. The mixed dispatching rule reduces WIP level of the system by enhancing the total throughput of the four production routes after the bottleneck (AN machine). The CONWIP release rule further reduces WIP by controlling the total amount of inventory in the system. With these four proposed strategies, we can have a pure pull system within AN and downstream machines and achieve significant reduction in cycle time and WIP.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2007

Author dc:creator

• Meng, Kai, M. Eng. Massachusetts Institute of Technology

Advisor dc:contributor.advisor

• Stephen C. Graves.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/42328

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/42328