Exploiting Deterministic Maintenance Opportunity Windows Created by Conservative Engineering Design Rules That Result in Free Time Locked Into Large High-Speed Coupled Production Lines With Finite Buffers

Abstract

Conservative engineering design rules for large serial coupled production processes result in machines having locked-in free time (also called 'critical downtime' or 'maintenance opportunity windows'), which cause idle time if not used. Operators are not able to assess a large production process holistically, and so may not be aware that they form the current bottleneck -or that they have free time available due to interruptions elsewhere. A real-time method is developed to accurately calculate and display free time in location and magnitude, and efficiency improvements are demonstrated in large-scale production runs. OPSOMMINGKonserwatiewe ingenieursontwerpreëls vir groot reeksgekoppelde produksieprosesse lei tot beskikbare vrye tyd (ook bekend as 'kritieke dooie tyd' of 'onderhoudsgeleenthede'), wat indien nie gebruik word nie, onbenutte tyd tot gevolg kan hê. Operateurs is nie in staat om ʼn grootskaalse produksieproses op holistiese wyse te beoordeel nie, en mag gevolglik nie besef dat hulle op ʼn bepaalde stadium óf die knelpunt is óf dat daar vrye tyd beskikbaar is as gevolg van onderbrekings elders nie. 'n Intydse metode is ontwikkel om vrye tyd akkuraat te bereken en te vertoon, beide wat posisie en grootte betref. Effektiwiteitsverbeterings word aangetoon in grootskaalse produksielopies.