Lessons learned from Angra 1

& Angra 2 NPP’s Outages

DO – Diretoria de Operação

SM.O – Superintendência de Manutenção

Preparado por: Luciano Junqueira Calixto

Email: lucical@eletronuclear.gov.br

Angra 1 & Angra 2 Data Angra 1:

• PWR – Westinghouse Design; • 121 Fuel Elements (33 control rods) – 12 months cycle;

• 2 loops (2 Steam Generators – 2 RCP’s);

• 1 HP and 2 LP turbines;

• Installed capacity: 640 MWe (1809 MWth);

• First criticality: 1981 - Commercial Operation since 1983;

Angra 2:

• PWR – Siemens / KWU design;

• 193 Fuel Elements (61 control rods) – 12 months cycle;

• 4 loops (4 Steam Generators – 4 RCP’s);

• 1 HP and 3 LP turbines;

• Installed capacity: 1350 MWe (3765 MWth);

• First Criticality: 2000 - Commercial Operation since Jan/2001;

Basic Outage Planning Milestones

Basic Outage Planning Milestones

General Outage Coordination Structure

Plant Manager

Or Deputy

Maintenance Coordinator

Operation Coordinator

System Engineer

Coordinator

RadiologicalProtection

Coordinator

Design Engineering Coordinator

Outage Coordinator

Quality Assurance

Coordinator

Outage Control Center Main Tasks

• Follow-up of Outage Activities, specially the critical path;

• Evaluate deviations and look for each Area Coordinator to

expedite the solution, in order to return to the original

schedule;

• Deliberate about changes on the critical path;

• Evaluate Nuclear Safety;

Angra 1 & Angra 2 basic Outage plan

Angra 2 Pre outage (10-12 days prior to outage):

• Inspection of safety components of Outage main redundancy,

such as 1 Safety Injection, 1 Component Cooling and 1 RHR

pumps, according to Preventive Maintenance plan or due to

Condition Based Monitoring;

Angra 1 & Angra 2 Major Maintenance Plan (30 day outage):

• Reactor unload and refueling (Exchange 1/3 of Fuel Elements);

• Review of 1 turbine item (HP, LP or Electric Generator);

• RCP seal inspection and Exchange of 1 motor;

• Inspection of 1 redundancy of Main Steam valves;

• SG inspection (Sludge Lancing and/or ECT);

• Major Design Modifications implementation;

• Inservice Inspections and safety MOV actuators revision;

• Electrical and I&C Tests / Inspections (such as Reactor

Protection);

• Circulating Water Motor inspection / exchange;

• Corrective and Elective Maintenance;

Maintenance during operating cycle

• Diesel Engine maintenance and associated Electric Generator

inspection;

• Limitation system - I&C tests (Angra 2);

• Predictive maintenance (vibration, oil analysis and termography)

of main componentes and electric panels;

• Minor Design Modifications;

• Water intake structure cleaning and material condition

maintenance;

• MOV current measurement and profile analysis / trend;

• Radiation detector tests (electronic and with rad. source);

• Corrective, Elective and minor Maintenance;

• Chill water turbocharger revision;

• Air compressor revision;

• Important to safety redundant instrumentation loop tests;

• Fan belt tension evaluation / adjustment;

• Lubricating;

Past Outages results

Angra 1:

Days

# T

asks

Past Outages results

Angra 2:

0

1000

2000

3000

4000

5000

6000

0

5

10

15

20

25

30

35

40

2P5 (2007) RCP 2P6 (2008) 2P7 (2009) 2P8 (2010) 2P9 (2012) 2P10 (2013) 2P11 (2014)

Days

# T

asks

Recent Challenges and Lessons Learned

• Angra 1 1P21 (2015) outage delayed 23 days due to an employee

Union’s strike;

• Spare parts and consumables import and Customs clearance

times;

• Temporary tools import and export time;

• Angra 2 2P11 (2014) delayed mainly due to Electric Generator test

equipment 6 days shipment delay;

• Manpower qualification during outages. Around 1000 temporary

contractors during outage (per plant);

• Stablishment of a long term (3-5 year) TG-set manufacturer

contract;

• Inservice inspection control prior and during outage, specially of

tests required for changing of “operation modes”;

• Stablishment of “Service Coordinators” for the critical path and

main inspection tasks;

• Preparation of a “Containment Arrangement” due to multiple /

concurrent task demanding polar crane inside containment;

Thank You !

DO – Diretoria de Operação

SM.O – Superintendência de Manutenção

Preparado por: Luciano Junqueira Calixto

Email: lucical@eletronuclear.gov.br