發電索賠場景——案例研究.pdf

1、SPONSORLUNCHPower Generation Claims Scenario Case StudyNeil Davis|SedgwickBhurima Tienwuttinun|MDD Forensic AccountantsIan Johnston|Clyde&Co ThailandDerek Gong|OskeferPower Generation Losses Case StudyAgenda The case study scenario The claim process The Cause Damage/remedial works Quantum assessment

2、 Property Damage Business Interruption Policy coverage concerns Subrogation/Recovery Questions(and answers?)Disclaimer:all photographs used in this presentation are for demonstration purpose only,which are not related to any specific loss.During normal operation a steam turbine trips on high vibrati

3、on.The plant operator contacts their appointed maintenance contractorInitial investigation by borescope shows significant damage to the last row of blades of the turbine,with failure of at least one blade.The loss is notified to insurersInsurers/reinsurers appoint a loss adjuster,and additional expe

4、rts are put on standbyPower Generation Loss Case StudyThe event scenarioGet ready for live pollingJoin live pollingAre you familiar with the claim handling process on a loss such as this?Live in 5 seconds12345Power Generation LossesSimplified claim processInvestigate and assesEstablish causeScope th

5、e remedial works Temporary and permanentApply Terms/Conditions/LimitationsCarry out the worksAddress on policy liabilityAddress quantum PD+BISettlementThe eventPower Generation LossesRoot Cause AnalysisRCA involves a systematic process of information gathering and evidence analysis.RCA Role of Techn

6、ical ConsultantInvestigate Cause(s)Common questions concerning gradual deterioration,fatigue,corrosion,wear and tear Proximate cause(s)and contributing factorsAssess Damage Extent Damage caused by the incident or separate issues Temporary repair vs.permanent repair Monitor the unit condition if temp

7、orary repair is conductedAssess Recovery Opportunities Identify other party could be potentially held liable for the incident Assist lawyers to assess the subrogation opportunity RCA ProcessActivities involved in RCAReview background information(such as incident report,CCTV footage)and technical doc

8、uments(such as design drawings,material specifications,maintenance records,DCS data,etc.)Conduct site inspection(and interview relevant personnel)to narrow down the initial failure point Further testing and analysis of selected samples,if requiredSimulation work,if requiredReportingCommunication wit

9、h stakeholders,such as loss adjuster,claim manager,lawyer,operator,OEMCollecting Background InformationSite Survey&SamplingVisual&Macroscopic ExaminationNon-destructive AnalysisDestructive AnalysisSimulation ExperimentComprehensive Analysis&ConclusionRecommendation on ChangesMonitoringInitial Invest

10、igationLaboratory AnalysisPost InvestigationRCA involves a systematic process of information gathering and evidence analysis.RCA ST LPT Blade FractureSite inspection and laboratory analysis identified that one last stage turbine blade failed through fatigue cracking.Fatigue cracking and release of o

11、ne blade on the last rowImpact damage to other blades on the last row and adjacent vanes Onset of fatigue cracking on the 2nd last row blades(without release of blade material)13Load Cycle second/minute/hour/day/month/year Examples:Low cycle fatigue:gas turbine working in peaking mode,frequent start

12、 up/shutdown 2 cycles per day High cycle fatigue:vibration at natural frequency,such as 50 HZ 50 cycles per second(4,320,000 per day)Fatigue:the process of progressive localised permanent structural damage occurring in a material subjected to conditions that produce fluctuating stresses and strains

13、at some point or points and that may culminate in cracks or complete fracture after a sufficient number of fluctuations(ASTM E1150)RCA What is Fatigue?A typical fatigue failure goes through three stages:Initiation:oCrack initiation is usually from material defect,surface imperfection,sharp edges,den

14、t,corrosion pits,etc.;oIt can take a long time to initiate a small crackPropagationoThe progression rate/speed depends on the load condition and material characteristic oFatigue does not necessary take a long time(days/months/years).And,what is a long time?Final fracture:oThe remaining area could no

15、t withstand the loadMost of the time,when people talk about fatigue,they actually mean the crack propagates through a fatigue mechanism,but ignores the crack initiation,which is equally,if not more,important.RCA Fatigue Crack Stageso Design loado Material specificationso Fatigue life assessmento Sha

16、pe formingo Machiningo Heat treatmento Mechanical propertyo Microstructureo Erosion resistanceo Corrosion resistanceo NDT o FOD or DODo Insulationo Re-assemblyo Load changeso Vibrationo Steam qualityo Contaminationo Alignmento Balancing o Insulationo FODoRoot cause confirmedoPotential contribution t

17、o RCoUnder investigation oNot relevantoPotential checking items in futureSteam Turbine Blade FailureDesign&SpecificationsManufacturing MaterialsInstallationOperationMaintenance&OverhaulRCA Factors to ConsiderThe fishbone diagram(Ishikawa cause and effect diagram)is a useful tool to map the potential

18、 contributing factors.RCA Considerations for ST LPT Blade Fatigue CrackingCrack Initiation FOD or DOD Corrosion Erosion Stress Concentration(e.g.,sharp edges)Microstructure(e.g.,impurity,improper heat treatment)Frequent load changesCrack Propagation Fatigue Mechanical Fatigue Corrosion FatigueFreque

19、ntly asked questions:1.Is fatigue equivalent to wear and tear?2.Does fatigue always occur through a long time?Fatigue(striations)Overload(dimples)Power Generation Loss Case StudyThe event scenario During normal operation a steam turbine trips on high vibration.The plant operator contacts their appoi

20、nted maintenance contractor Initial investigation by borescope shows significant damage to the last row of blades of the turbine,with failure of at least one blade.The loss is notified to insurers Insurers/reinsurers appoint a loss adjuster,and additional experts are put on standby Established cause

21、 Fatigue failure of a blade on the last row Established extent of damage Extensive damage to last row of blades.Minor damage to last row of vanes.Identified onset of cracking(probably fatigue)on the second last row of blades What next?Power Generation Loss Case StudyThe event scenarioEstablished cau

22、se Fatigue failure of a blade on the last rowEstablished scope of damage Extensive damage to last row of blades.Minor damage to last row of vanes.Identified onset of cracking(probably fatigue)on the second row of bladesWhat next?Replace all blades on two rows localised repair to damaged vanesTempora

23、ry works Use available refurbished blades Minimise plant downtimeReplace with all new blades once availableProceed to assess quantum and policy responsePolicy Trigger Policy Trigger:Damage,which is “sudden physical loss of or damage to the Insured Property which the Insured could not reasonably have

24、 foreseen.”What is sudden?Common law/civil law Physical loss.Contamination Is there fortuity?What is reasonably foreseeable?Technical bulletins/recycled partsGet ready for live pollingJoin live pollingWhen is the policy triggered?Live in 5 seconds1234523Case Example-ScenarioCircumstances A single fl

25、ow steam turbine failed-fatigue of the initial failed blade Refurbished blades available-vanes can be refurbished on site Unit resumed operation 60 days after the date of loss months 1 to 2=0%output Output resumed at 85%capacity for safety New blades will require 9 months to arrive months 3 to 11=85

26、%output Installation and recommissioning of new blades requires 15 days Insured has plan maintenance scheduled on month 15 Several options in the period of new blades installationBI Policy ADV deductible for 30 days Maximum indemnity period 12 monthsExample Wording of ADV.The Insured shall bear at i

27、ts own risk a sum equivalent to the applicable number of days stated in the Schedule of this Policy multiplied by the Average Daily Value in respect of each and every loss giving rise to a claim under this Section of this Policy.For the purposes of this Deductible Average Daily Value shall mean(in r

28、espect of each and every loss giving rise to a claim under this Section of this Policy)the amount of the claim payable under this Section of this Policy(prior to the application of the Deductible)divided by the length in days of the Indemnity Period applicable in respect of the claim.The Indemnity P

29、eriod shall be measured from the time and date of the physical loss or damage.ScenariosA)Planned maintenance(PM)brought forward to month 12 loss stops at 11 months,month 12 permanent repair overlaps with PMB)Carry out permanent repair in month 12 despite PM planned for month 15 half of month 12=0%ou

30、tput.loss stops at 11.5 monthsC)Permanent repair pushed back to month 15 to align with planned PM month 12 till PM=85%output The Initial Figures:A)PM Brought ForwardThe Initial Figures:B)Install despite PM The Initial Figures:C)Installation Pushed BackSummary of Initial FiguresConsiderations Can del

31、ivery be shortened?would air freight be economic against loss of turnover avoided?If delivery is delayed loss would increase&ADV decreases Can the Insured operate at higher capacity and reduce loss?If there was no loss during the refurbished blades period,should we include those days in the ADV calc

32、ulation?Get ready for live pollingJoin live pollingIn this scenario,would a waiting period deductible or an ADV deductible provide a higher indemnity?Live in 5 seconds12345All Risks Insuring clause:“Damage by any cause or peril not otherwise excluded by this Policy.”Common exclusions that might be r

33、elevant Wear&tear,gradual deterioration Corrosion Slowly developing cracks Known issues Defects.Write backs Ensuing loss Loss caused by causes not otherwise excluded33C.O.D.Incident gradual damage/crack(s).Sudden/Defined Damage gradually developing damage COVER?COVER?DEFECT TRIGGER Defects/DamageGet

34、 ready for live pollingJoin live pollingDoes fatigue fall under the wear and tear exclusion?Live in 5 seconds12345Key takeaways Fatigue does not have to be a long-term failure mechanism but often is The cover comes into effect when the trigger occurs not when(if applicable)a defect is created The ap

35、plication of exclusions/coverage limitations on this type of claim can hinge on the specific details of the particular loss and the particular policy wordings.It is important to understand the difference between an ADV and a waiting period BI deductible.The outcome for the claim could vary significantly.Recovery Subrogation Responsibility for the loss OEM or LTSA or sub-contractor Rights of recovery under contracts Limitations Exclusions Warranty periods Waivers of subrogation rights Contractual waivers Waivers in repair contract Time barQ&ASPONSORAFTERNOON COFFEE