Mathematical Models for Optimal Reliability Decisions Kurtuluş Barış Öner Radj Bachoe IOP-IPCR Symposium System Availability Up; Life Cycle Cost Down December 2, 2010
Motivation Capital Goods Lifetime: 10-30 years Availability is crucial Life Cycle Costs (LCC) or Total Cost of Ownership (TCO) Downtime costs ~ 50% of TCO Maintenance costs + Downtime costs ~ 75% of TCO Design Production Exploitation Disposal Costs: K P M IOP-IPCR Symposium: Availability up; LCC down 13-12-2010 PAGE 1
Reliability Decisions Reliability levels l of components Redundancy Costs K + P Downtime Costs D M M + λd Total costs K + P MTBF(Mean Time Between Failures) MTBF* MTBF K(MTBF): Design costs P(MTBF): Production costs M(MTBF): Maintenance costs D(MTBF): Downtime λ: Downtime cost rate IOP-IPCR Symposium: Availability up; LCC down 13-12-2010 PAGE 2
Key Aspects and Costs Key Aspects Multiple systems Spare parts inventory Emergency procedure Spare parts inventory level is optimized Critical components Costs Factors Incorporated Design and production costs (acquisition costs) Spare parts inventory costs Maintenance costs Downtime costs (availability constraints) t IOP-IPCR Symposium: Availability up; LCC down 13-12-2010 PAGE 3
Reliability Decisions - Results Reliability levels of component Optimal MTBF increases as a function of number of systems downtime cost rate (availability requirement) system lifetime Costs Total costs M + λd K + P MTBF* MTBF IOP-IPCR Symposium: Availability up; LCC down 13-12-2010 PAGE 4
Reliability Decisions - Results Redundancy d Costs 2.8 x 107 TCO vs Availability 2.6 2.4 2.2 TCO 2 1.8 1.6 λ 1.2 λ* 1 No Redundancy Redundancy 0.96 0.965 0.97 0.975 0.98 0.985 0.99 0.995 1 1.4 Availability 25 systems with 40 components IOP-IPCR Symposium: Availability up; LCC down 13-12-2010 PAGE 5
Effects of the Research New product development Deals with suppliers Options for customers Service logistics Service contracts Service operations Spare parts inventory IOP-IPCR Symposium: Availability up; LCC down 13-12-2010 PAGE 6
A workbook including tools Tools are available at: http://www.utwente.nl/mb/ompl/iop-ipcr/ IOP-IPCR Symposium: Availability up; LCC down 13-12-2010 PAGE 7
Vanderlande Industries Praktische implicaties Life Cycle Costing Tools IOP Conferentie 2 december 2010
Vanderlande Industries Vanderlande Industries, Radj Bachoe Geintegreerde logistieke oplossingen - 60 jaar ervaring - Ontwerpen, - Implementeren, - Operatie - Service 2000 medewerkers waarvan 40% in de service dienst verlening Omzet 655 Mio in 2009
Vanderlande Industries, Service Service evolutie van VI SERVICE ONE-STOP-SHOP & MAINTENANCE PROVIDER PARTS PROVIDER & WARRANTY MNGT 1995 2008 Tijd Van Re-actief naar Pro-actief Van onderdelen leverancier naar kennis center
Key van de ontwikkelde tool Key issues voor Life Cycle Costing tools Consistentie Reproduceerbaarheid Flexibiliteit Gebruik praktijk data LCC Tools Gebruik De ontwikkelingen staan niet stil, het model ook niet!! Aanpassen Leren
Voorbeeld: klant propositie Uit werk van Rutger Vlasblom, winnaar SLF afstudeerprijs 2010 Basis systeem Departure Carousel Departure Carousel Alternatieve systemen X-ray X-ray X-ray X-ray Check in 1-12 Check in 13-27 Check in 28-39 Check in 40-54
Voorbeeld: Toeleveranciers Robustere besturing Impact van nieuwe e materialen a e Impact van End Of Life (EOL)
Voorbeeld: Operatie modellering Simulatie Operatie monitoring Effecten interactie mens-machine
Voorbeeld: R&D, Life Cycle Conceps Impact van nieuwe producten Definitie van benodigde test data Robuust maken van het systeem Voorkomen van operator fouten
Samenvatting Tool: Consistentie en praktijk gegevens Organisatie: Centrale kennis borging en toegang Toepassing: Verschillende invalshoeken eisen veel flexibiliteit
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