collection and analysis of component failure data …

ENTE PER LE NUOVE TECNOLOGIE, L'ENERGIA E L'AMBIENTEAssociazione ENEA-EURATOM sulla Fusione

FUSION UNITTECHNOLOGIES DIVISION

COLLECTION AND ANALYSIS OF COMPONENT FAILURE DATA FROM JET SYSTEMS

10th of July 2006

T. Pinna (1) , G. Cambi(2), F. Gravanti (1)

(1) Thermonuclear Fusion Division - Safety & EnvironmentVia E. Fermi 45, I-00044, Frascati (Rome), Italy e-mail: [email protected] , [email protected]

(2) University of Bologna, Physic DepartmentVia Irnerio 46, I-40126 Bologna, Italy, e_mail: [email protected]

OBJECTIVE (1)

8th IAEA TM on FPPS - July 2006

To develop a fusion specific component failure database with data coming from operating experiences gained in various fusion laboratories

The activity began in 2001 with the study of data from the JET Vacuum system and Active Gas Handling System (AGHS), plus data from the Tritium Laboratory of Karlsruhe (TLK)

Two years later the Neutral Beam Injectors (NBI) and Power Supply (PS) systems were considered and,

in this last year the Ion Cyclotron Resonant Heating (ICRH) system is under evaluation.

OBJECTIVE (2)

Collect all the information available about single component malfunctions and failures of the systems under investigation, pointing out causes, consequences, maintenance actions

Collect information useful to evaluate probabilistic valuesrelated to component malfunctions and failures

Estimate the main reliability parameters, (such as the failure rate and the corresponding standard errors and confidence intervals), associated to the components

Point out practical information on the operating experienceacquired



Neutral Beam Injectors

ASYNC Mode

SYNC Mode

Component malfunctions and failures in NBI boxesAbout 100 failures were identified since the beginning of operations up to March 2004

Faults related to components in NBI Boxes

0 5 10 15 20

Accelerator stackBox scrapers

CalorimeterCentral Support

Cryo plantCryo pump

Deflection MagnetsDuct liner/scrapers

Fast shutterFull energy ion

Ion SourceMagnet liners

NBI diagnosticsNeutraliser

N° of Faults

Trend of failures related to components in NBI boxes

0

20

40

60

80

100

120

1985 1987 1988 1990 1992 1994 1996 1998 2000 2002


Cooling channels (electrodeposited → drilled)Bellows (single → twin)Cooling line layout to avoid water freeze-upsInability to accurately predict power densities in the duct region under the different magnetic fields

Statistical analysis: Constant Failure Rate Model

TN

=λ

λ= Historical failure rate (/h)N = Observed number of failures over time TT = Timescale derived from period of historical data record

T = Σ(Operating time of single component * N° of components)

Mean time between failures (MTBF)Uncertainty values:

standard error s.e.(λ), lower λL and upper λU limits of the 90% confidence interval


Statistical analysis: Constant Failure Rate Model

nfPD =

PD= Failure of component on demand (/d)f = Observed number of failures on demandn = number of demands from historical data record

n = Σ(number of demands on single component * N° of components)

Mean number of demands between failures (MDBF)Uncertainty values:

standard error s.e.(PD), lower (PDL) and upper (PDU) limits of the 90% confidence interval


NBI: Number of pulses/operating days

SYNC & ASYNC Pulses in the period January 1994 - March 2004

0

10000

20000

30000

40000

50000

60000

1994 1995 1996 1996 1997 1998 1999 2000 2001 2002 2003

N°

of p

ulse

s

NBI4-PulsesNBI8-Pulses

SYNC & ASYNC Pulses versus Operating days

0

10000

20000

30000

40000

50000

60000

0 200 400 600 800 1000 1200 1400 1600 1800

Operating days

N° o

f pul

ses

NBI4-PulsesNBI8-Pulses

Trends of NBI Operating days

0200400600800

10001200140016001800

1994 1995 1996 1996 1997 1998 1999 2000 2001 2002 2003

N° o

f Ope

ratin

g da

ys

NBI4NBI8

NBI-4 NBI-8

SYNC 17 20

ASYNC 20 21


NBI boxes: Operating life of componentsNBI Component Cooling hours in op.days Operating time during pulses Number of

(h) (s) (h) Cycles

Filaments 5.09E+5 1.05E+6 291 6.54E+5

Ion Source 5.09E+5 1.05E+6 291 6.55E+5

Accelerator 5.09E+5 1.07E+6 298 6.55E+5

Neutraliser 5.09E+5 1.11E+6 309 6.55E+5

Full Energy Ion Dump 6.36E+4 5.68E+5 158 1.49E+5

Bending Magnet 6.36E+4 3.28E+7 9108 1.49E+5

Calorimeter Front (Async) 6.36E+4 7.73E+4 21 7.73E+4

Calorimeter Back (Sync) 6.36E+4 4.88E+5 136 7.17E+4

Box Scraper Mk1 -88 to 02 1.77E+4 1.39E+5 39 2.05E+4

Box Scraper Mk2/3 - 94 to 01 3.34E+4 2.64E+5 73 3.88E+4

Box Scraper Mk4 - 01 to 04 1.25E+4 8.45E+4 23 1.24E+4

Box Scraper 6.36E+4 4.88E+5 136 7.17E+4

Duct Scraper 6.36E+4 4.88E+5 136 7.17E+4

Fast shutter 6.36E+4 4.88E+5 136 7.17E+4

Central Support Column 6.36E+4 5.68E+5 158 1.49E+5

NBI Diagnostics 6.36E+4 3.28E+7 9108 1.49E+5

NBI boxes 6.36E+4 5.68E+5 158 1.49E+5


NBI boxes: searching of reference components (low level)

Welds (Lip, But, Fillet, Brazed welds)

Flanges (Bolted flange, Cefilac, Commercial Fittings)

Cooling pipesCooling channels (Made by drilling, electro-deposition, other)

Electrical insulatorsFeedthroughs (Electrical, Water coolant, Cryogenic, Gas)

Valves (Vacuum, Coolant, Cryogenic, Gas)

Bellows and HosesInstrumentation (Temperature, Pressure, Flow, Other)

Etc.

~ 540 different parts of components for a sum of 40,216 items have been outlined


NBI boxes: Statistical evaluationsGlobal data

With regard to full day operating hours

With regard to pulse duration With regard to number of pulses

λ s.e.(λ) MTBF λ s.e.(λ) MTBF pD s.e.(pD MDBF(1/h) (h) (1/h) (h) (1/demand) (cycles)

NBI4 2.6E-4 8.6E-5 3860 1.1E-1 3.8E-2 9 1.2E-4 3.9E-5 8442NBI8 2.1E-4 8.5E-5 4816 7.7E-2 3.1E-2 13 8.2E-5 3.4E-5 12177NBIs 2.4E-4 6.1E-5 4242 9.5E-2 2.5E-2 11 1.0E-4 2.6E-5 9936

NBI

265 days


NBI boxes: Statistical evaluations


Samples of data evaluated for the NBI componentsWith regard to full

day operationWith regard to pulse

durationWith regard to n° of

cycles performedλ MTBF λ MTBF pD MDBF

(1/h) (h) (1/h) (h) (1/dem.) (cycles)

Accelerator stack - Water leak 1 2.0E-6 5.1E+5 3.4E-3 298 1.5E-6 6.5E+5

Box scrapers - Water leak 1 1.6E-5 6.4E+4 7.4E-3 135 1.4E-5 7.2E+4

Calorimeter - Misalignment 1 1.6E-5 6.4E+4 6.4E-3 157 6.7E-6 1.5E+5

Calorimeter - Water leak 0 1.4E-5 6.9E+4 5.8E-3 171 6.1E-6 1.6E+5

Central Support Column - Water leak 1 1.6E-5 6.4E+4 6.3E-3 158 6.7E-6 1.5E+5

Cryo pump - Leak 1 1.6E-5 6.4E+4 6.3E-3 158 6.7E-6 1.5E+5

Deflection Magnets - Failure 1 1.6E-5 6.4E+4 1.1E-4 9108 6.7E-6 1.5E+5

Duct liner/scrapers - Water leak 0 1.4E-5 6.9E+4 6.7E-3 148 1.3E-5 7.8E+4

Fast shutter - Vacuum Leak 1 1.6E-5 6.4E+4 7.4E-3 136 1.4E-5 7.2E+4

Fast shutter - Water leak 3 4.7E-5 2.1E+4 2.2E-2 45 4.2E-5 2.4E+4

Ion dumps - Water leak 0 1.4E-5 6.9E+4 5.8E-3 172 6.1E-6 1.6E+5

Ion Source - Water leak 3 5.9E-6 1.7E+5 1.0E-2 97 4.6E-6 2.2E+5

Neutraliser - Water leak 2 3.9E-6 2.5E+5 6.5E-3 155 3.1E-6 3.3E+5

Bellow - Leak 3 3.7E-7 2.7E+6 1.7E-4 5971 1.8E-7 5.6E+6

Cooling channels - Water Leak 3 2.0E-8 4.9E+7 2.2E-5 45309 1.4E-8 6.9E+7

Filament – Failure 219 2.5E-5 4.0E+4 4.4E-2 23 2.0E-5 5.1E+4

Hose - Water leak 4 1.4E-7 7.2E+6 1.8E-4 5413 1.0E-7 9.5E+6

Piping - Water leak 1 9.8E-9 1.0E+8 4.7E-6 213031 6.4E-9 1.6E+8

Component failures N° of Faults


POWER SUPPLY system

Coil PS

Schematic of Poloidal Field power supply sub-system

NBI PS

Component malfunctions and failures in PS system

2150 failures/malfunctions for the Power Supply system sinceJanuary 1997 up to May 2003 have been collected in the JET Logging System

About 1935 records are related to Coil PS and NBI. They havebeen classified:

Main Component/ System

Type of failure /malfunction

Component/ Subsystem in fault conditions

Failure Mode

Causes

Efforts to classify PS events => ~ 1000 h x 2 PPY8th IAEA TM on FPPS - July 2006

Classification of failures/malfunctions on PS system


Failures/malfunctions on PS system


Code Description N° of failures/malfunctionsGrid 400kV 400kV Distribution System 25Grid 36kV 36kV Distribution System 33PFGC Poloidal Flywheel Generator Converter 54TFGC Toroidal Flywheel Generator Converter 50PF-P1 Poloidal Field - P1 Coil 12PF-OH Poloidal Field - Ohmic Heating system 195PDFA1/4 Poloidal Diverter Field Amplifier 1/2/3/4 50PVFA Poloidal Vertical Field Amplifier 90PVFB Poloidal Vertical Field Booster 19FRFA Fast Radial Field Amplifier 82DFAS Disruption Feedback Amplifier System 16TF-Coil Toroidal Field - Coils 5TF-SU Toroidal Field - Static Units 87DMSS-PF Direct Magnet Safety System - Poloidal Field 6DMSS-TF Direct Magnet Safety System - Toroidal Field 7RPC Reactive Power Compensation 70CODAS Control Data Acquisition System (general) 13CPS Coil Protection System 140MDS CODAS - Machine Diagnostic System 29NBI Power Supply of Neutral Beam Injectors (general) 20NBI4 Power Supply of Neutral Beam Injectors in Octant 4 415NBI8 Power Supply of Neutral Beam Injectors in Octant 8 417NBI-TB Power Supply of Neutral Beam Injectors - Test Bed 43AncW Ancillary - Water cooling system (general for all PS systems) 2AncA Ancillary - compressed Air (general for all PS systems) 3AncP Ancillary - Power Supply Low Voltage (general for all PS systems) 4NoId Not Identified 2None Not Significant 40


Failures/malfunctions on Coil PSFailures/malfunctions in Coil Power Supply systems

0 50 100 150 200

Ancillary systems

Control systems

DFAS

DMSS

FGCs

FRFA

Grid 400kV / 36kV

PDFA

PF-OH

PVFA&PVFB

RPC

TF-SU

N° of Faults

Main component or large Unit interested by the faults

0 50 100 150 200

Air cool. system

Compressed air systemAncillary Power Supply

Water cool.systemBusbar

CapacitorCircuit breaker -ac -36kV

Circuit breaker -Disconnector -36 kV

CODASProtec.& Contr.Sys.

Coil -CPSConverter

CrowbarElectrical filter

FGCsGrid 400kV / 36kV

InductorRPC Unit (general)

Resistor

Switch -Earth switchSwitch -Switchgear

Switch -Vacuum switch -36kVTransformer

Not significant

N° of Faults


Failures/malfunctions on Coil PSFailures/malfunctions in Coil Power Supply systems

0 50 100 150 200

Ancillary systems

Control systems

DFAS

DMSS

FGCs

FRFA

Grid 400kV / 36kV

PDFA

PF-OH

PVFA&PVFB

RPC

TF-SU

N° of Faults


0 50 100 150 200

Air cool. system

Compressed air systemAncillary Power Supply

Water cool.systemBusbar

CapacitorCircuit breaker -ac -36kV

Circuit breaker -Disconnector -36 kV

CODASProtec.& Contr.Sys.

Coil -CPSConverter

CrowbarElectrical filter

FGCsGrid 400kV / 36kV

InductorRPC Unit (general)

Resistor

Switch -Earth switchSwitch -Switchgear

Switch -Vacuum switch -36kVTransformer

Not significant

N° of Faults

Low level compon. or ancill. subsyst. in fault conditions without I&C

0 10 20 30 40 50 60

Ancillary Air cool. System - FanAncillary Compressed air system

Ancillary Oil cool.systemAncillary Oil lubrificat.system

Ancillary system - Power SupplyAncillary system - PSACS

Ancillary Water cool.systemBusbar - dcCapacitor

Circuit breaker - acCrowbar

FGC - Pony motorFuse

HeaterNetwork PSSnubber - ac

Solid state device - DiodeSolid state device - Thyristor

Switch - Earth switchSwitch - Switchgear

Switch - Vacuum switch - 36kV - Transformer

Not identifiedNot significant

N° of Faults


N° of Faults / NBI boxes

0 50 100 150 200 250 300 350 400 450

NBI generic

NBI4

NBI8

NBI-TBTrend of NBI PS failures/malfunctions

0

50100

150200

250300

350400

450

01/01/97 01/01/98 01/01/99 01/01/00 31/12/00 31/12/01 31/12/02 31/12/03

NBI genericNBI4NBI8NBI-TB

Failures & malfunctions in NBIs versus Operating days

y = 0.9708x - 233.28

0100200300400500600700800900

1000

0 200 400 600 800 1000 1200

N° of operating days since January 1997

N° o

f fau

lts


0 50 100 150 200

NBI PS Module (generic)

Compressed air

SF6 supply

Water cool.system (generic)

Protec.& Contr.Sys.

Transmission Line

Auxiliary PS (FIL,ARC,SB)

Grid 1Protection Unit

Grid 2 PS

Grid 3 PS

Circuit breaker -ac -36kV

HV - Rectifier PS

Magnetic Field Compensation PS

Magnet PS

Not identified

Not significant

N° of Faults

Failures/malfunctions on NBI PS


Failures/malfunctions in PS systems during pulses

1E-3 1E-2 1E-1 1E+0

Ancillaries (general for PS plant)

CPS

DMSS

FRFA

Grid 400kV / 36kV

MDS

PDFA

PVFA1/4

PVFA5/6

PVFB

RPC

PF-OH

FGCs (both)

PFGC

T FGC

T F-SU

NBIs (both)

NBI4

NBI8

Fail . Rate (1/h ) for C omp. O N

PS: Statistical evaluationsGlobal data

Coil and NBI PS troubles with regard to operating days

1E-2 1E-1

Coil PS Systems - Generic trouble

Coil PS Systems - Alarm/Erratic Alarm/Failto preset

Coil PS Systems - Fail to operate/Spuriousoperation

NBI PS Systems - Generic trouble

NBI PS Systems - Alarm/Erratic Alarm/Failto preset

NBI PS Systems - Fail to operate/Spuriousoperation

Fail. Rate (1/h)

PS: Statistical evaluations

On average more than one trouble (1.2 trouble/day) occurred every day of operations (16 h/day) for the Coil PS and one trouble/day for the NBI PS.

55 % of the Coil PS troubles were due to “Alarm” or “Erratic Alarm” indicating a failure or a malfunction of the systems or “Failure to preset” the systems to operate. The other 45 % of the troubles were due to “Failure to operate” or “Spurious operation” of the system components.

72 % of the NBI PS troubles were due to “Alarm” or “Erratic Alarm” indicating a failure or a malfunction on the systems or “Failure to preset” the systems to operate. The other 28 % of the troubles were due to “Failure to operate” or “Spurious operation” of the systems.


PS: Statistical evaluations


Samples of data evaluated for the PS componentsWith regard to full

day operationWith regard to pulse

durationWith regard to n° of

cycles performedλ MTBF λ MTBF pD MDBF

(1/h) (h) (1/h) (h) (1/dem.) (cycles)

Busbar - Generic fault 5 1.6E-6 6.4E+5 1.3E-5 76918 1.5E-6 6.5E+5

Capacitor - Generic fault 7 3.9E-5 2.6E+4 3.6E-3 280 3.0E-5 3.3E+4

Circuit breaker-ac-36kV - Generic fault 91 2.2E-4 4.6E+3 6.4E-3 157 4.6E-3 2.2E+2

Converter - Generic fault 267 4.1E-4 2.4E+3 3.7E-2 27 2.2E-4 4.6E+3

FGC Unit- Fail to operate 16 5.4E-4 1.9E+3 5.7E-2 18 4.8E-4 2.1E+3

FGC - Pony motor - Generic fault 7 2.4E-4 4.2E+3 2.5E-2 40 2.1E-4 4.8E+3

FGC - Air cooling system-Generic fault 20 6.7E-4 1.5E+3 7.1E-2 14 6.0E-4 1.7E+3

FGC - Oil lubrif. system - Generic fault 8 2.7E-4 3.7E+3 2.9E-2 35 2.4E-4 4.2E+3

FGC - Water cool.system- Generic fault 5 1.7E-4 5.9E+3 1.8E-2 56 1.5E-4 6.7E+3

Resistor – Generic Alarm 19 6.4E-7 1.6E+6 6.8E-5 14649 6.1E-6 1.6E+5

Resistor - Burn out 8 3.8E-6 2.6E+5 8.6E-3 116 2.5E-6 4.0E+5

Solid state device - Fault 24 2.6E-7 3.8E+6 4.2E-5 23700 2.2E-7 4.6E+6

Switch - Earth switch - Generic fault 43 3.7E-7 2.7E+6 1.7E-4 5971 1.1E-3 9.2E+2

Switchgear - Generic fault 167 2.0E-8 4.9E+7 4.6E-2 22 7.1E-4 1.4E+3

Transformer 400/36 kV_300 MVA–Gen.Alarm 33 2.0E-4 5.0E+3 4.4E-2 23 2.0E-5 5.1E+4

Vacuum switch -36kV - Generic fault 36 2.0E-4 5.0E+3 2.1E-2 47 1.8E-4 5.6E+3

Component failures N° of Faults

Overview on the data collection activity (1)

AGHS: about 130 failures on a set of 6259 components, operating for about 156 767 000 hours, have been pointed out since 1995 up to January 2002

Vacuum system: about 600 failures on a whole set of 4012 components, operating for about 249 450 000 hours, have been pointed out since March 1983 up to January 2002

TLK: 52 failures on a set of 584 components, operating for about 10 746 732 hours, have been pointed out up to October 2002



From AGHS

Failure Rate of Indicator types for "Erratic/No output" faults (1/h)

0.0E+00 1.0E-06 2.0E-06 3.0E-06 4.0E-06 5.0E-06 6.0E-06 7.0E-06

Indicator - Flow

Indicator - Humidity

Indicator - Level

Indicator - Pressure

Indicator - Temperature

Indicator - Tritium

Indicators -

Failure Rate of Vacuum Pump faults (1/h)

0.0E+0 5.0E-6 1.0E-5 1.5E-5 2.0E-5 2.5E-5 3.0E-5 3.5E-5

Normetex - External leakMetal Bellow - Fail to start

Turbomolecular - Fail to startMetal Bellow - Pump stop

Normetex - Pump stopRotary vane - Pump stop

Turbomolecular - Pump stopVacuum Pumps - Generic

Failure Rate of Valves faults (1/h)

1.8E-5

0.0E+0 5.0E-7 1.0E-6 1.5E-6 2.0E-6 2.5E-6 3.0E-6

Air Actuated - Fail to open/closeNon return - Fail to open/close

Solenoid - Fail to open/closeAir Actuated - Internal Leak

Pressure control - Fail to operatePressure Regulator -

Solenoid - External leakValves - generic fault




Windows Failure Rates (1/h) during Normal Operations

0.0E+0 1.0E-6 2.0E-6 3.0E-6 4.0E-6 5.0E-6 6.0E-6 7.0E-6 8.0E-6 9.0E-6

Windows 10÷100 Ø - Leak

Windows 100÷250 Ø - Leak

Windows - Leak

Windows 10÷100 Ø - Rupture

Windows 100÷250 Ø - Rupture

Windows - Rupture

Windows 10÷100 Ø - Leak/Rupture

Windows 100÷250 Ø - Leak/Rupture

Windows - Leak/Rupture

Failure Rate λ (1/h) during Normal Operations

1.0E-8 1.0E-7 1.0E-6 1.0E-5

Bellows - LeakBurst Disks - Leak

DNnnn - LeakRHnnn - Leak

Flanges - LeakCommerc.Fitt. - Leak

Flanges/Fittings - Leak

F/T Cryo - LeakF/T El - Leak

F/T Gas - LeakF/T Lq - Leak

F/T Lq - Water LeakF/T - Generic Leak

Gauges - Leak

Valves - Fail to operateValves - External LeakValves - Internal Leak

Valves - Generic Failure

Butt Welds - LeakFillet Welds - Leak

Lip Welds - LeakWelds - Leak

Windows - LeakWindows - Rupture


VacPump - Leak

From VS


Installation/Operation failures comparison

0 50 100 150 200

Bellows - Leak

DNnnn - Leak

RHnnn - Leak

Commerc.Fitt . - Leak

Flanges/Fittings - Leak

F/T - Generic Leak

Gauges - Leak

Valves - External Leak

Valves - Internal Leak

Butt Welds - Leak

Fillet Welds - Leak

Lip Welds - Leak

Welds - Leak

Windows - Leak

Windows - Rupture


Total number of failures

Installation

Operation

Operation failures comparison between Critical and No-critical leaks

0 10 20 30 40 50

Bellows - Leak

DNnnn - Leak

RHnnn - Leak

Commerc.Fitt. - Leak

Flanges/Fitt ings - Leak

F/T - Generic Leak

Gauges - Leak

Valves - External Leak

Valves - Internal Leak

Butt Welds - Leak

Fillet Welds - Leak

Lip Welds - Leak

Welds - Leak

Windows - Leak

Windows - Rupture


Total number of failures

No-critical

Critical

From VS8th IAEA TM on FPPS - July 2006



Mean leak sizes for JET vacuum system failures

1.0E-5 1.0E-4 1.0E-3 1.0E-2 1.0E-1 1.0E+0 1.0E+1 1.0E+2 1.0E+3

Bellow - LeakBellow - Water Leak

Burst Disk - Leak

F/T Cryo - LeakF/T El - Leak

F/T Gas - LeakF/T Lq - Leak

F/T Lq - Water Leak

Gauge - LeakGauge - Water Leak

ComFit - LeakDNnnn - LeakRHnnn - Leak

RHnnn - Leak O'Ring

Valve - External LeakValve - Internal Leak

Butt welds - LeakFillet welds - Leak

Lip welds - Leak

Window - LeakWindow - Rupture

mbar l/s

InstallationOperation


ICRH: 4741 events of failures/malfunctions have been identified and classified for the operating period March 1996 – November 2005. Daily pulses have been counted for a total of 897 days with ICRHplasma pulses. Report to be reviewed by JET Operators.

This activity is set in the frame of Task 5 of the IEA Agreement

Data collected in the “Fusion Component Failure Rate Database”.


ACKNOWLEDGMENT

The authors have to thank members of the JET Groups:

Neutral Beam Injectors,

Power Supply,

Active Gas Handling System,

Vacumm System,

Ion Cyclotron Resonance Heating,

Close Support Unit and,

TLK Group for the supplying of data used in this study


collection and analysis of component failure data …

Documents