“DBDS & CORROSION FREE” Programme: Diagnosis and ... - Cigré

Sea Marconi - Laboratory 3/3©2009 Sea Marconi Technologies sas - All Right ReservedAdvanced analysis methods.Quality certification:ISO 9001/2001; ISO 17025-2000Our laboratory analysis is amongthe best in the world:• for the range of testsperformed• for the technologicallyadvanced instrumentation• for the methodologies usedSINAL-ILAC CERTIFICATIONAccreditated tests:- PCB, PCT, PCBT, according toIEC 61619:1997-04;EN 12766-3:2004EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Sea Marconi - Methods 1/4Integrated methods for Diagnosticand Treatments similarto “Human Blood”……contacting internal organs for which diagnosticTests and dialysis therapies” is metaphorically used©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 20093

Sea Marconi - Methods 2/4Rapresentative Sampling forDiagnostic Tests©2009 Sea Marconi Technologies sas - All Right ReservedTransformer oil“Human Bood”EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Sea Marconi - Methods 3/4Dedicated laboratoryanalyses for diagnostics©2009 Sea Marconi Technologies sas - All Right ReservedSea Marconi lab“Typical Hospital lab”EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 20094

Sea Marconi - KitsInspection andSampling Kit Deos TR ®Plastic bag for deliverySamplingdatasheetSingle-use glovesSingle use flasks(125 ml)Luer plastic cap©2009 Sea Marconi Technologies sas - All Right ReservedGlass syringe (50 ml)labelKit DeosTR ® andDeosTR+ ® do notinclude:- paper or tissues forcleaning,- vessels for waste oiland liquids,- fitting plugs forconnection.Three way valven. 2 silicon pipesplug (¼”)EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Sea Marconi - Methods 4/4Integrated, in continuous andon-load fluid treatments©2009 Sea Marconi Technologies sas - All Right ReservedDMU by Sea Marconi forIntegrated treatments of oil“Human Blood Dialysis”EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 20095

Sea Marconi – Technologies DMUTypical DMU configurationIntegrated treatments: Decontamination,Depolarization, Detoxification©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Sea Marconi - Multifunctional TechnologiesMultifunctional Technologies and ProcessMain functionPhysicaldecontaminationCHEDCOSdepolarisationCDP PROCESS ®dehalogenationRecovery of dielectricpropertiesRecovery of the chemicalproperties of the oil (acidity,delta tg, colour)©2009 Sea Marconi Technologies sas - All Right ReservedElimination of sulfur corrosivecontaminants, DBDSElimination of dissolvedorgano-metallic contaminantsDetoxification ofPCBs/PCTs/PCBTs, POPs,compounds etc.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 20096

Sea Marconi - PCBs Free SolutionsCDP Process ®©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Sea Marconi – CDP Process ®After CDP Process ® , riclassification“NO PCB” of Transformer and Oil©2009 Sea Marconi Technologies sas - All Right ReservedBefore dehalogenationAfter dehalogenationEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 20097

Transformer in oilNikola Tesla inventor(10/071856 – 7/01/1943)©2009 Sea Marconi Technologies sas - All Right Reserved• “Electrical Transformer” Patent n. 493,138,November 2, 1887• “Electrical Transformer or induction device”, Patent n.433,702, August 15, 1890• “Method of Insulating Electric Conductors”Patent n. 655,838, August 14, 1900“my invention any kind of fluid capable ofmeeting the requirements (75…) as oil, may beused (130…)”EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Transformer applicationsTransformer and insulating liquids in generation,transmission and distributionfor electrical networks©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 20099

Transformer Fleet©2009 Sea Marconi Technologies sas - All Right ReservedFLEET & FAMILY- Type- Power (MVA)- Voltage (KV)- Age (year)- Fluid- Manufacturers- Value (€)- Consuming lifeEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Insulating OilsPCAs/PAHs©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200910

Scenario OECD©2009 Sea Marconi Technologies sas - All Right ReservedOil & Generation Transformers - Asset value• > 10,000 million litres of insulating oils• Typical replace value is more than 1 € / litre• Insulating Oil represent ~ 6% value of transformer• Insulating Oil represent ~ 25% weight of transformer€OECD - Total Asset Value: GenerationPower Transformer> 150,000 million€ - EuroEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Typical FaultsDBDS &CorrosiveSulfurElectricalFault-ArchingPaper degradationand sludging©2009 Sea Marconi Technologies sas - All Right ReservedCopper in oil mg/kgService Period (Years)43No-SulfurCorrosionThermal Fault-Hot spot> 700 °CEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200911

FocusProtection of Resources Assets & EnvironmentFailureExplosionFireInfancy OccasionalOld age©2009 Sea Marconi Technologies sas - All Right ReservedDamages• Direct: Assets & Personal• Indirect: Production• Environment: soil, water, airBlack-OutEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009FocusPrevention and/or mitigation of……Black-Out impact (3 to 36 hours)©2009 Sea Marconi Technologies sas - All Right ReservedNo energy for:• > 55 milion people (September 2003 in thewhole of Italy)• > 15 milion people (August 1994 Southern Italyonly)• Industries (petrochimicals, steel-mills,mechanical)• Services (hospitals, schools, research, utilities)• DefenceEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200912

IEC StandardsIEC 60296 and IEC 60422©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009IEC Standards©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200913

IEC Standards©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009IEC Standards©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200914

IEC Standards©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009CIGRE Recommendations©2009 Sea Marconi Technologies sas - All Right ReservedThe recommendationsfor concentration limitfor Corrosive Sulfurcompounds in oils(CIGRE A2.32 figure 9,pag. 31):• “

Case historyCase history of Total Sulfur in oil(considerable reduction since 1990)DISTRIBUTION TRANSFORMERS (

Case historyCase history of Dissolved Copper in oil(considerable increment since 1990)DISTRIBUTION TRANSFORMERS (

Corrosion phenomenaMaterials present in a transformer:Iron, copper and other (minor) metalsOil/insulating liquidsCellulose or other solid insulationWood and pressboardsRubber, glues, polymers, etc.©2009 Sea Marconi Technologies sas - All Right ReservedPossible chemical interactions between different materials:Acid corrosion (oil to copper, oil to iron)Formation of complexes (oil to copper, oil to iron)Catalysis of redox reactions (acids, water, additives)Oxidation (oxygen, peroxides to oil/cellulose)Dissolution of soluble compounds (oil to rubber, oil to polymers)EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Corrosion phenomenaContaminants resulting from corrosion:Dissolved copper (and other metals)Suspended copper (and other metals)Copper complexesInsoluble copper salts (copper sulfides, copper oxides)©2009 Sea Marconi Technologies sas - All Right ReservedClassification of corrosion phenomena:Related to copper sulfide formation (Corrosive Sulfur)copper sulfide growth on naked conductorscopper sulfide growth on solid insulationRelated to copper formation (NO-Sulfur Corrosion)dissolved/suspended copper in oilcopper deposition/adsorption on solid insulationEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200918

Failures (1/6)LinesCase history of failuresDue to Corrosive Sulfur on a 500 KV line – BrazilSubstationsTotal reactorsTSNReactors withCorrosive SulfurTotal failed reactors1181 km64037(92,5%)15(37,5%)©2009 Sea Marconi Technologies sas - All Right ReservedLinesSubstationsTotal reactorsNovatransReactors withCorrosive SulfurTotal failed reactors1278 km63613(36,11%)-EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Failures (2/6)Corrosive Sulfur: related failuresFailures related to Corrosive Sulfur encountered in lastyears©2009 Sea Marconi Technologies sas - All Right ReservedFailurePresence of deposits of Cu 2 SEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200919

Failures (3/6)Corrosive Sulfur: related failuresCopper sulfide: main cause of fault or co-factor?©2009 Sea Marconi Technologies sas - All Right ReservedHeavy formation ofcopper sulfide on nakedcopper, failure due to adischarge between LVconductors and thegrounded tankEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Failures (4/6)Corrosive Sulfur: related failuresCopper sulfide: main cause of fault or co-factor?©2009 Sea Marconi Technologies sas - All Right ReservedHeavy formation of coppersulfide on inner solidinsulation, failure due to aturn-to-turn dischargeEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200920

Failures (5/6)Corrosive Sulfur: related failuresCopper sulfide: main cause of fault or co-factor?INNERLAYER©2009 Sea Marconi Technologies sas - All Right ReservedOUTERLAYERCopper sulfidefound on innerlayer of cellulose.[Cu] > 10% byweightEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Failures (6/6)Corrosive Sulfur: related failuresCopper sulfide: main cause of fault or co-factor?©2009 Sea Marconi Technologies sas - All Right ReservedEvidence of generaloverheating in thefaulty winding.High temperaturewas the main factor ofthe fault.Copper sulfidefound onconductors.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200921

DBDS DiscoveryJuly 2005, DBDS in oil - First identificationSea Marconi’slaboratory©2009 Sea Marconi Technologies sas - All Right ReservedIFED (IntegratedFingerprinting &Elemental Diagnostics)techniques, usingHRGC-AED&MSEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009DBDS confirmationDBDS (DiBenzylDiSulfide) in Oil“Sulfur compound, very corrosive tometal surface (i.e. steel, copper and silver) atnormal operating temperatures”©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200922

DBDS confirmationDBDS “Antioxidant additive ” in oil©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009DBDS confirmationExample of IFED of “Sulfur profiles” in oil©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200923

DBDS confirmationOilDBDSCuTemperature > 100 °CCU 2 S©2009 Sea Marconi Technologies sas - All Right Reserved“Winding Hot-spot temperature in °C” Ref.IEC 60076-7 Ed. 1“Power Transformer – Part. 7: Loadingguide for oil – immersed powertransformers”EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009DBDS & OccurrenceOccurrence of DBDS in corrosive oils©2009 Sea Marconi Technologies sas - All Right ReservedConsidering as 10 mg/kg of DBDS the threshold to make anoil corrosive, 93,4% of oils in this population takes itscorrosiveness from DBDSEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200924

DBDS & Corrosive SulfurA typical mechanism for conversionof DBDS in copper sulfide and byproducts©2009 Sea Marconi Technologies sas - All Right ReservedSSSSHCH 3+CuDBDST (> 100 °C)Cu 2S/CuS+Cuprous/cupric sulphideDibenzyl sulphide Bibenzyl Toluene Benzyl mercaptan StilbeneEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009DBDS & Corrosive SulfurDBDS & Corrosive Sulfur: related failuresCopper sulfide: main cause of fault or co-factor?Copper sulfide found oninner layer of cellulose.[Cu] > 4% by weightSymptom: decay of DBDSduring the serviceDBDS' trend©2009 Sea Marconi Technologies sas - All Right Reservedmg/kg of DBDS2502001501005001995 1998 2001 2004 2006 2009 2012YearsEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200925

Potentially Corrosive Sulfur – CCD TestNew methods …ASTM D 1275 BRif. Non corr. Corr. … ?©2009 Sea Marconi Technologies sas - All Right ReservedCCD test (IEC 62535)EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Potentially Corrosive Sulfur – CCD Test©2009 Sea Marconi Technologies sas - All Right ReservedThe Qualitative Test Method (IEC 62535 Ed.1 2008-10) canprovide results “False Positive” (up to 80% of ”PotentiallyCorrosive”), in case of used and /or degraded oils and “FalseNegative” (100% of “No-Potentially Corrosive), in case of oils withDBDS (typical range 150-250 mg/Kg) but with passivatoradditives, masking the visual effects during the 72 hours of thetest.In case of doubts in the interpretation of inspection result of thepaper, the composition of the precipitate must be analyzed withother methods as, for example, the SEM-EDX. This is a complexinstrumentation, very expensive, not easy available, providing, inany case, qualitative results onlyEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200926

Total Corrosive Sulfur - SM-TCSThe new Quantitative SM-TCS Test Method (SeaMarconi - Total Corrosive Sulfur, patent applied for)©2009 Sea Marconi Technologies sas - All Right ReservedSampleNo.GC – ECDGC-MS GC-AED SM-TCSDBDSDBDS DBDS DBDS eq.mg/kgmg/ kg mg/kg mg/KgLab. Lab. Lab. Lab. Lab. Lab. Lab. Lab. Lab. Lab.A B C* D E A B C* F C*37 – A 129 116 126 141 144 146 113 139 147 138 13437 – B 129 106 133 142 103 1 143 113 141 165 135 13137 – C 71 76 62 83 143 1 76 59 85 95 88 8437 – D 4.00

Total Corrosive Sulfur - SM-TCSWashing solventsDeionized water©2009 Sea Marconi Technologies sas - All Right ReservedPipettesNeedles for syringesPlastic syringesBottles for finalsolutionsSilicon tubeFilters (P.A. 0.45 μm)Sealed vialswith copperpowder andmagnetic bar(Argonatmosphere)Gloves Litmus Aluminium capsReagentsEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Total Corrosive Sulfur - SM-TCSSample preparationReaction between oil & copper - oxidation©2009 Sea Marconi Technologies sas - All Right ReservedSulphates dissolution in waterSulphates quantificationEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200928

Oil Fingerprinting Profile – SM – IFED (1/6)©2009 Sea Marconi Technologies sas - All Right ReservedThe new SM-IFED Test Method (Sea Marconi -Integrated Fingerprint & Elemental Diagnostic –patent pending) solves all types of analyticaluncertainty and interpretation doubts withresults referred to a univocal comparison(Qualitative and Quantitative) of the “Data BaseProfiles”EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Oil Fingerprinting Profile – SM – IFED (2/6)SM-IFED Results:” Paraffin-Base Oil”- AGIP ITE 360-1989CarbonIFED with GC-AEDfingerprintingSulfur©2009 Sea Marconi Technologies sas - All Right ReservedDistillation profileCarbonSulfurEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200929

Oil Fingerprinting Profile – SM – IFED (3/6)SM-IFED Results: “Naphthenic Base Oil with DBDS”-NYNAS NYTRO 10 GBNCarbonIFED with GC-AEDfingerprintingSulfurDBDS©2009 Sea Marconi Technologies sas - All Right ReservedDistillation profileCarbonSulfurEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Oil Fingerprinting Profile – SM – IFED (4/6)SM-IFED Results: “Naphthenic Base Oil with DBPC &NO-DBDS”-NYNAS 10 XN-2005CarbonDBPCIFED with GC-AEDfingerprinting©2009 Sea Marconi Technologies sas - All Right ReservedSulfurEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200930

Oil Fingerprinting Profile – SM – IFED (5/6)SM-IFED Results: “Naphthenic Base Oil with DBDS”- Oils Producer A & BBehind the brand name, IFED shows realityCOil A, ItalianproducerThese two oils were proposed to onecustomer by two different oil companies(one Italian, one German), withdifferent brands and different names.SDBDSOils have the same carbon and sulfurfingerprint.They are the same oil.©2009 Sea Marconi Technologies sas - All Right ReservedCSOil B, GermanproducerDBDSEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Oil Fingerprinting Profile – SM – IFED (6/6)SM-IFED Results: “Naphthenic Base Oil withMedium Total Sulfur & NO-DBDS”-Oil Producer X©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200931

“DBDS & Corrosion Free Program” - Key Factors©2009 Sea Marconi Technologies sas - All Right Reserved1. Age: from 1988;2. Type of mineral insulating oils: naphthenic base uninhibitedoil without antioxidant additives (DBPC); other type of oilsblended with naphthenic oil contaminated by Corrosive Sulfur;3. Type of equipment: GSU; Shunt Reactors, HVDCtransformers; industry transformers (rectifier, furnace, etc);highly loaded transmission transformers and secondly on otherpower or strategic transformers; OLTC; Bushings; Instrumenttransformers;4. Top-up or oil change: > 5- 10 %;5. High load; High temperature;6. Thermal fault: DGA (type: T1,T2,T3); trends in oxygencontent symptoms of overheating;7. Total Corrosive Sulfur Compounds (> 5 mg/kg) and or DBDS(> 10 mg/Kg) for unused oil. Typical concentration of DBDS:range 150-250 mg/Kg) and trends symptoms of formation ofcopper sulfide;8. No spare part unit available;9. Sister unit had suspect failure in the last 20 years;10. Voltage level >220 KV.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009ABC INVENTORY of strategic units by familiesIdentify one strategic unit representing eachfamily of the same fleet of equipment, possiblyby the same manufacturer, through an analysisof the following factors of evaluation:©2009 Sea Marconi Technologies sas - All Right ReservedA-Age : < 5 years; 5-10 years; >10-20 years;B-Type: GSU; Shunt reactors, HVDCtransformers; industry transformers (rectifier,furnace, etc.); highly loaded transmissiontransformers and secondly on other power orstrategic transformers;C-Power (MVA): 100EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200932

ABC Diagnostic Coverage of strategic units - ABC Trend(1/3)©2009 Sea Marconi Technologies sas - All Right Reserved1. A - Evaluation of the “Family historicalanamnesis” B - “Equipment” C - “Symptoms”2. External inspection (“Signs”) of the equipment;3. Representative sampling of the insulating liquidof each equipment (A; B; C);4. Analysis (“Symptoms”) by an ISO 9001credited and expert laboratoryEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009ABC Diagnostic Coverage of strategic units - ABC Trend(2/3)©2009 Sea Marconi Technologies sas - All Right Reserved4.1. Total Corrosive Sulfur-SM-TCS;4.2. Oil Fingerprint Profile- SM-IFED with GC/AED4.3. Potentially Corrosive Sulfur (CCD) –IEC 62535;4.4. DiBenzyl DiSulfide (DBDS) with GC/MS & AED or ECD-IEC TC10 WG 37;4.5. Metal Passivator additives - Ciba Irgamet 39;4.6. Metal Passivator additives - Benzotriazole-BTA;4.7. Inhibitor additive content - DBPC-IEC 60666;4.8. Total Sulfur Content with ICP;4.9. Dibenzylsulfide (DBS) with GC/MS &AED;4.10. Bisbenzyl (BiBZ) with GC/MS;4.11. Dissolved Metals (Copper, Iron, Zinc, Tin, Silicon, Silver,Alum.) with ICP;4.12 Copper Deposition Test (on the CCD paper) with ICP;4.13 Particles (counting and sizing) - IEC 60970;4.14 Dissolved Gases (DGA) - IEC 60657 and IEC 60599;4.15.2 Furfural and related compounds (Furans)-IEC 61198;4.16 Water content - IEC 60814;4.17 Total Acidity Number (TAN) - IEC 62021;4.18 Dielectric Dissipation Factor (DDF) - IEC 60247;4.19 Resistivity - IEC 60247;4.20 Aspect and Color — ASTM D 1500;EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200933

ABC Diagnostic Coverage of strategic units - ABC Trend(3/3)©2009 Sea Marconi Technologies sas - All Right Reserved5. Trend Analysis, Evolution Rate, Data Basematching;6. Diagnosis with interpretation of the Facts(Anamnesis, Signs, Symptoms) and TestReports7. Countermeasures for each unit representing afamilyEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Post mortem and/or post failures diagnosis©2009 Sea Marconi Technologies sas - All Right ReservedIt becomes necessary to perform post mortemand/or post failure inspections for diagnosticprotocol to prevent and/or mitigate criticalfactors on fleets of equipment in operationbelonging to the same family.A typical example on a GSU Transformer of anIntegrated Gasification Combined Cycle(IGCC).Case History: Equipment Type- GSU; Power192 MVA; Voltage max 400 KV; Year-1998;Manufacture A; Oil Type - Naphthenic Base Oilwith DBDS; Oil Producer A; DBDS 110 mg/kg;Year of Failure 2006.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200934

Post mortem and/or post failures diagnosisA case of failure related to Corrosive Sulfur (1 di 7) Inspection and Analisys on internal HV windings3-4/October/2006OPENING OF THE TRANSFORMER©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Post mortem and/or post failures diagnosisA case of failure related to Corrosive Sulfur (2 di 7) Inspection and Analisys on internal HV windings©2009 Sea Marconi Technologies sas - All Right ReservedPressboard damagedby the failureFailure area, extendedabout 30x30 cmFrom the outside, the failure appears due to electric discharge at the 17°turn, radial sector 8 (numbering the sectors from 1 through 24 incounterclockwise direction, no. 1 is in correspondence with the HV contact).EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200935

Post mortem and/or post failures diagnosisA case of failure related to Corrosive Sulfur (3 di 7) Inspection and Analisys on internal HV windings©2009 Sea Marconi Technologies sas - All Right ReservedSinusoidal deformations of the windings,sector opposite to the failureInternal view of the HV winding,failure zoneEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Post mortem and/or post failures diagnosisA case of failure related to Corrosive Sulfur (4 di 7) Inspection and Analisys on internal HV windingsMAPPING OF THE COPPER CONTAMINATION©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200936

Post mortem and/or post failures diagnosisA case of failure related to Corrosive Sulfur (5 di 7) Inspection and Analisys on internal HV windingsVISUAL MAPPING OF THE COPPER SULFIDE DEPOSITS©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Post mortem and/or post failures diagnosisA case of failure related to Corrosive Sulfur (6 di 7) Inspection and Analisys on internal HV windingsMAPPING OF THE THERMAL DEGRADATION©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200937

Post mortem and/or post failures diagnosisA case of failure related to Corrosive Sulfur (7 di 7) Inspection and Analisyson internal HV windings©2009 Sea Marconi Technologies sas - All Right ReservedCOLLECTION OF PAPERS FROMTHE WINDING- Internal conductors of the windingheavily contaminated by copper sulfide.The strong corrosiveness of the oil(corrosiveness code: 4c, by repeatedanalyses according to ASTM D 1275 Aext. 48h) caused the deposition ofelevated amounts of copper sulfide onthe paper components.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions“DBDS & Corrosion Free Program”©2009 Sea Marconi Technologies sas - All Right ReservedThe “DBDS & Corrosion Free Program” has thepurpose of preventing/mitigating the risksassociated with Corrosion Phenomena for thebest protection of the fleet of equipment andoils (unused and used) through diagnostic,inventory, management and integratedtreatments of insulating liquids for Life CycleManagement of transformer.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200938

Solutions > Countermeasure no. 1For Unused Oil©2009 Sea Marconi Technologies sas - All Right ReservedSupply technical specifications and standard references :A. Additional requisites required by the purchaser and certified bythe supplier for each lot of mineral insulating oil provided andequipment:- compliance with standard IEC 60296 Ed 3 2003-11- presence and concentration of each type of additive (IEC60296 clause 5.4);B. Absence of DBDS (DiBenzylDiSulfide < 5mg/Kg) and/or othertypes of “Corrosive Sulfur” compounds in accordance with methodIFED with GC-AED&MS technique;C. “Potentially Non Corrosive” compliance with IEC 65535 (CCD) and“DownSize” Test, 150°C, 48 hours-ASTM 1275-BD. Total Corrosive Sulfur – SM-TCS Countermeasure no. 2 (1/3)For Unused Oil, inspection in tanks and drums©2009 Sea Marconi Technologies sas - All Right ReservedA. Compliance of the oil with the specifications and standard IEC60296 Third edition 2003-11B. Compliance of the oil with the specifications for the presence andconcentration of additives (anti-oxidants, passivators etc.);C. Compliance for the absence of DBDS (DiBenzylDiSulfide

Solutions > Countermeasure no. 2 (2/3)IEC TC10 WG 35Maina R., Tumiatti V.Madrid, 6/11/2006Copper Deposition TestTests on Cigre’s RRT oils, copper quantified by ICP-AES [Cu]=mg/Kg©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009©2009 Sea Marconi Technologies sas - All Right ReservedSolutions > Countermeasure no. 2 (3/3)CIGRE 3Cu = 3909 mg/Kg(kd = 31,27)S - Non corrosive(?)NaphthenicDBDS =

Solutions > Countermeasure no. 3 (1/2)Factory test of strategic equipmentPrescriptions for the supply of oil for first impregnation©2009 Sea Marconi Technologies sas - All Right ReservedA. Compliance of the oil with the specifications and standard IEC60422 Third edition 2005-10B. Compliance of the oil with the specification for the presence andconcentration of additives (anti-oxidants, passivators etc.);C. Compliance for the absence of DBDS (DiBenzylDiSulfide

Solutions > Countermeasure no. 4For Oil and equipment in operation©2009 Sea Marconi Technologies sas - All Right ReservedA. Compliance with standard IEC 60422 Third edition 2005-10,clause9 Table 3B. Integrating management requisites for each equipment andcharge of insulating oil with specific tests and monitoring:- presence and concentration of every type of additives (IEC60296 Ed 3 2003-11 clause 5.4)C. Compliance for the absence of DBDS(DiBenzylDiSulfide < 5 mg/Kg) and/or other types of corrosivecompounds in accordance with method IFED with HRGC-AED&MStechniqueD. “Potentially Non Corrosive” compliance with IEC 65535 (CCD) and“DownSize” Test, 150°C, 48 hours-ASTM 1275-BE. Total Corrosive Sulfur – SM-TCS Countermeasure no. 5Management of oils in operation, sampling, tests,corrective actions and treatment of the oils©2009 Sea Marconi Technologies sas - All Right ReservedA. Compliance with standard IEC 60422 Third edition 2005-10, clause10, 11,12 tables 4, 5, 6);B. Compliance with the specification for the presence and concentrationof additives (anti-oxidants, passivators etc.);C. Compliance for the absence of DBDS (DiBenzylDiSulfide < 5mg/Kg)and/or other types of corrosive compounds in accordance withmethod IFED with HRGC-AED&MS techniqueD. “Potentially Non Corrosive” compliance with IEC 65535 (CCD) and“DownSize” Test, 150°C, 48 hours-ASTM 1275-BE. Total Corrosive Sulfur – SM-TCS

Solutions > Countermeasure no. 6Metal passivating additives for oil inoperation with BenzoTriAzoles (BTA) andderivativesCiba-Irgamet 39 ® NyPass©2009 Sea Marconi Technologies sas - All Right ReservedA. Metal passivators are not able to decompose the DBDS andcorrosive sulfur compounds and “is not a guarantee againstfailures” (CIGRE A2.32 Art. 4.1 Mitigation techniques. Metalpassivators page 19)B. Sampling and monitoring of passivating additives after each oiltreatment performed in compliance with standard IEC 60422Third edition 2005-10 art 12 (reconditioning, reclamation,dehalogenation). It is known that under normal vacuum and/orreclamation conditions, the concentration of passivatingadditives (100 mg/Kg) is considerably reduced if not eliminated,depending upon the type of process, operational temperatureand pressure;C. Tests and monitoring of the concentration of passivatingadditives through time.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions > Countermeasure no. 6 (1/7)Typical metal passivator additiveCiba Irgamet 39 ®©2009 Sea Marconi Technologies sas - All Right ReservedCase history is reported “In a population of 21 transformers,preventive action was taken in July and August 2005. Because ofthe shortage of safe oil, only five reactors could be retrofilled andthe remaining 16 were passivated. As of December 2006, eight ofthe latter group failed in service, respectively at 33, 102, 136, 168,284, 363, 478, and 590 days after passivation. No failure have sofar occurred for any of the retrofilled units in this group” (CIGREA2.32 Oil exchange, art. 4.3 pag.25)EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200943

Solutions > Countermeasure no. 6 (2/7)Example of stray gassing following thepassivation with Ciba Irgamet 39©2009 Sea Marconi Technologies sas - All Right ReservedHydrogentrendPassivationEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions > Countermeasure no. 6 (3/7)Decay of Ciba Irgamet 39 and its effect onoil’s corrosivenessIrgamet 39 conc. (mg/kg)140120100806040200©2009 Sea Marconi Technologies sas - All Right Reserved24/03/200613/05/200602/07/200621/08/2006Sampling date10/10/200629/11/200618/01/2007EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200944

Solutions > Countermeasure no. 6 (4/7)Risks correlated topassivating additivesBenzoTriAzoles (BTA) andderivatives©2009 Sea Marconi Technologies sas - All Right ReservedTo evaluate the compliance with Europeanregulation 1907/2006 of 18/12/2006"REACH" (Registration, Evaluation andAuthorization of Chemicals) and the safetyrequisites of IEC TC111 and IEC Guide 109WG 16, approved during the Plenary Meeting2000 in Geneva.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions > Countermeasure no. 6 (5/7)Risks correlated to the by-products ofBenzoTriAzoles and derivatives©2009 Sea Marconi Technologies sas - All Right ReservedTo evaluate the type and concentration of thedecomposition substances generated by partialdischarges, long-term thermal stress andpyrolysis under uncontrolled reaction conditionson the various catalytic surfaces (ex. iron,copper, etc.)EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200945

Solutions > Countermeasure no. 6 (6/7)Risks correlated to the byproductsof BenzoTriAzolesand derivatives©2009 Sea Marconi Technologies sas - All Right Reserved“Studies have pointed out that benzotriazole ismutagenic in in-vitro bacterial cellules, but not inthe mammal cellular systems. The report does notprovide conclusions, but defines that benzotriazolemust be considered as a “suspect humancarcinogen”.- Stouten, H, Rutten, AJL, van de Gevel, IA, De Vrijer, F, 2000. Nordic Expert Group forCriteria Documentation of Health Risks from Chemicals and the Dutch Expert Committee onOccupational Standards: 126. 1,2,3-Benzotriazole. National Institute for Working Life.Stockholm, Sweden- National Cancer Institute Technical Report Series No. 881978 “Bioassay of 1H-Benzotriazole for possible carcinogenicity CAS No. 95-14-7 “ NCI-CG-TR-88 - U.S.department of Health, Education, and Welfare Public Health Service National Institutes ofHealth.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009©2009 Sea Marconi Technologies sas - All Right ReservedSolutions > Countermeasure no. 6 (7/7)Irgamet 39 ®Chemical nature: Isomeric mixture of isomerica N,N-bis(2-etilesil)-4-metil-1H-benzotriazol-1-metilammina e N,N-bis(2-etilesil)-5-metil-1H-benzotriazol-1-metilammina (Numeri CAS: 80584-90-3,80595-74-0)Numero CAS 80584-90-3 + 80595-74-0Indication of dangersClassified as dangerous in accordance with ECDirectivesXi IrritantN Dangerous forthe environmentIt requires the implementation of specialFire Prevention MeasuresEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200946

Solutions > Countermeasure no. 7 (1/6)Selective depolarisation with theelimination of DBDS and “NONCORROSIVE” classification©2009 Sea Marconi Technologies sas - All Right ReservedA. DBDS and corrosive sulfur compounds can be decomposed from theoils with “Selective Depolarisation (a combination of reagents andsorbents)”.(…) in “Continuous on-line treatment” (CIGRE A2-32 art.4.2 page 25)B. Multi-functional decontamination and depolarisation of oil andequipment (including dissolved metals that cannot be eliminated bya normal reclaiming process) capable also of reinstating theinsulating properties of the oils in accordance with standard IEC60422 Ed. 3 2005-10 clause 12 and table 5C. Additivation (if required) of the oil with oxidation inhibitors typeDBPC at 0,3% in weightEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions > Countermeasure no. 7 (2/6)Chemical decomposition of DBDS withselective depolarisation process©2009 Sea Marconi Technologies sas - All Right ReservedConcentration (mg/kg)160140120100806040200DBDSIrgamet 390 1 2 3 4 5 6 7 8 9 10Number of treatment cylesEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200947

Solutions > Countermeasure no. 7 (3/6)DMU (Decontamination Mobile Unit) for“On Load Selective Depolarisation Process”©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions > Countermeasure no. 7 (4/6)Selective Depolarisation andDBDS eliminationDBDS©2009 Sea Marconi Technologies sas - All Right ReservedBefore DepolarizationAfter DepolarisationEffect of the CHEDCOS ® selective depolarisationprocess: chemical decomposition of corrosivecompounds “DBDS”EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200948

Solutions > Countermeasure no. 7 (5/6)Typical results for “On-Load selective depolarisationprocess” – GSU transformer 192 MVA 400KV©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions > Countermeasure no. 7 (6/6)Case history > 100 transformers for “On-Load & Offloadselective depolarisation process”©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200949

Solutions > Countermeasure no. 8 (1/2)Oil Exchange©2009 Sea Marconi Technologies sas - All Right ReservedTo guarantee DBDS concentration < 10 mg/kg (after 90 days) itsnecessary to exchange the oils twice.The typical concentration of the DBDS in “Unused mineral insulating- Naphthenic Base with DBDS” is 150-250 mg/Kg. This oil changeevidently reduces the corrosive compounds content of the oil,diluting them accordingly with the ratio between the new oiladded and the remnant old oil (which results from the addition ofthe oil adsorbed on the active part and the oil remaining in thebottom of the tank).That typical ratio may be 10% (CIGRE A2.32-art. 4.3 pag. 25) ormore, depending on the amount of paper and other adsorbingmaterials, and on the shape of the tank also. When the oil is tobe changed, a preventive test of corrosive sulfur on a suitablemixture of the old and the new oil should clarify if the mitigationaction will be adequate to obtain finally a non corrosive oil.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions > Countermeasure no. 8 (2/2)Crossed contamination of usedoil by DBDS (bulk reclamation)©2009 Sea Marconi Technologies sas - All Right Reservedmg/Kg60,0050,0040,0030,0020,0010,000,001b 1a 2b 2a 3b 3a 4b 4a 5b 5aSamplesSampleConcentration of dibenzyldisulfide in samples before (b) and afterreclamation (a). GC-MS and GC-ECD analyses.1 According to ASTM 1275 B (150°C, 48 h)1b1a2b2a3b3a4b4a5b5amg/KgDBDS20,9522,0022,5213,6550,0414,0312,6417,7515,4712,46Corrosivesulphur 14a4a4a4a4a4a4a4a4a4bEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200950

Solutions > Countermeasure no. 9Replacement of windings-spare parts©2009 Sea Marconi Technologies sas - All Right ReservedA. The corrosion process and the formation of coppersulfides are irreversible. The Selective Depolarisationand oil exchange are not able to eliminate thedeposit trapped on insulating papers and windings.B. The deposit of copper sulfides accumulated does notmodify the DP of papers, but modifies, in anirreversible manner, the insulating electric propertiesthat could become critical.C. Under this critical condition, it is necessary toreplace the components, the windings and/or theequipment.EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions > Countermeasure no. 10 (1/6)No-Sulfur Corrosion and Effects on losses©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200951

Solutions > Countermeasure no. 10 (2/6)Copper content in corrosive andnon-corrosive oils©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions > Countermeasure no. 10 (3/6)Copper deposited on paper surface©2009 Sea Marconi Technologies sas - All Right ReservedCopper in paper after ageing (mg/kg)60005000400030002000100000 50 100 150 200 250 300Oil 1 - Naphtenic HG - Type I - NC ageing time @ 150°C (hours)Oil 2 - Paraffinic StdG - Type U - NCOil 3 - Naphtenic StdG - Type U - COil 3 - Naphtenic StdG - Type U - C (+ Air)EMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200952

Solutions > Countermeasure no. 10 (4/6)Copper in oil before and after oil exchange©2009 Sea Marconi Technologies sas - All Right ReservedCopper content (mg/kg)14121086420007/1998 12/1999 04/2001 09/2002 01/2004 05/2005 10/2006 02/2008Date (month/year)Oil change0,450,40,350,30,250,20,150,10,05DDFCopperDDFEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Solutions > Countermeasure no. 10 (5/6)Copper in oil and DDF decayafter oil depolarization©2009 Sea Marconi Technologies sas - All Right ReservedCopper in oil (mg/kg)5045403530252015105011/200105/200212/2002Oil depolarisation06/200301/200408/2004DateCopper in oil (mg/kg)02/200509/200503/200610/20061,41,210,80,60,40,20DDF of oilDDFEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200953

Solutions > Countermeasure no. 10 (6/6)Case history of Selective Depolarisationof organo-metallic compounds in oil©2009 Sea Marconi Technologies sas - All Right ReservedCopper in oilEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Conclusions©2009 Sea Marconi Technologies sas - All Right ReservedThe “DBDS & Corrosion Free Program” isable to prevent and/or mitigate the“Corrosion Phenomena”.The countermeasures suggested representthe Best Available Techniques (BAT) for theLife Cycle Management (LCM) of strategicelectrical equipments filled with mineralinsulating oilsEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200954

My Transfo do Brasil 2009 - September 22,23,24©2009 Sea Marconi Technologies sas - All Right ReservedEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 2009Thank you for your kind attentionQ & A©2009 Sea Marconi Technologies sas - All Right ReservedWorld Wide Sustainable Solutions for our Future“We are the products of the Environment where we live and work”Vander TumiattiEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200955

Since 1968www.seamarconi.comIdeas and Innovation for Energy and EnvironmentContacts©2009 Sea Marconi Technologies sas - All Right ReservedVander TumiattiSea Marconi TechnologiesVia Ungheria 20, Collegno (Turin - Italy)Tel. +39 011 234.34.34Fax +39 011 234.34.35E-mail: tumiatti@seamarconi.itEMPRESA ELÈCTRICAS CHILENAS Y CIGRE – 12/13 August 200956