CAVLAR ® Ilse Pieterse-Quirijns
400 mm NGIJ Valve failure III 500 mm GGIJ Valve failure II 300 mm GGIJ Known valve failure Mains replacement Failure of valves: – I (known): 2 extra valves, no extra customers – II: 4 extra valves plus extra customers – III: 5 extra valves plus extra customers Valves can fail
CAVLAR ® Quantifying the contribution of valves (or the fialure of valves) to the supply of drinking water
CAVLAR ® CAVLAR ® : Criticality Analysis Valve Locations And Reliability Location valves: section analysis of distribution network Reliability of valves: calculate performance distribution net critical sections critical valves Effect of valve maintenance: improvement valve reliability improvement of performance distribution net 1 2 3
CAVLAR ® : required input Required information: LIS data: Failure data: Maintenance data: Volendam number of connections, length, diameter failure probability supply interruption durance valve reliability
Insight in existing distribution net Number of sections Number of valves per section Connections per section Number of sections Volume per section (m3) Number of sections
Location of valves Section: number of connections diameter length failure probability Valve: Reliability Section diagram
Adjust valve configuration
Adjust valve configuration (2)
New valve locations: comparison of configurations Original configuration New configuration less dependent sections new config.: less valves in a section 50% of valves more connections in a section norm Groningen:< % of sections
Reliability of valves: critical sections (1) For each section CAVLAR ® calculates performance indicators at a certain valve reliability: Impact : number of connections Ratio : impact/number of connections in section CML (min/section/year): minutes that costumer does not have water CI (1/year): customer interruptions highest CML critical sections
Performance indicator: Impact Ratio CI CML critical section critical valves Reliability of valves: critical sections (2)
159 conn. 3 valves I = 181 Ratio = CML = 06:54:08 CI = vave rel.=0.90 Critical section 1: A_123Y Reliability of valves: critical sections (3)
Reliability of valves: critical sections (4) First 10 (5%) sections: 24% of total CML First 22 (10%) sections: 40 % of total CML
Reliability of valves: critical sections (5) Judge new valve configuration based on CML number of valvesreliabilitynumber of sectionsCML [min] original configuration :01 new configuration :56 new configuration + maintenance :42 x 0.5x 0.33x 2.3 CML improvement : 18.7% weight reduction operational costs and CML increase optimalisation valve configuration
Influence of increased valve reliability 0:00:00 0:07:12 0:14:24 0:21:36 0:28:48 0:36:00 0:43:12 0:50: valve reliability [-] CML [min/conn./year] original configuration new configuration
Effect of valve maintenance: Judge maintenance scenarios Maintenance of valves: increase of valve reliability effect maintenance for Winschoten: improvement CML with 18.7% CAVLAR ® determines prioritization of valves (ranking valves with diminishing effect on performance of distribution net) input for maintenance scenarios
Effect of maintenance on CML maintain 50% of most critical valves 75% of max. possible result same effect with maintenance of 22% of most critical valves to higher reliability btbh 0.95 btbh 0.98 willekeurig naar 0.95
Conclusion Roll of CAVLAR ® : tool for optimisation of distribution network tool for prioritisation of sections and valves tool for advise in maintenance plans Smart maintenance:good maintenance of critical valves results in same performance Smart configuration:judgement and optimisation of valve configuration