September 15, Reliability Safety - Management Engineering services Software development

Transcription

1 Reliability Safety - Management Engineering services Software development

2 The purpose of this presentation is to present the activities performed for assessment of the current state and residual lifetime of the components of the control and monitoring systems and the electrical equipment of Kozloduy NPP Units 5&6. The complex examination of the actual state and assessment of the residual lifetime of the Monitoring and Control Systems (MCS) of Kozloduy NPP Units 5&6 has been implemented in order to determine the actual state and elaborate a preliminary assessment of the systems residual lifetime, so that the possibilities and conditions for prolongation of the Units service life could be determined, as well as elaborate programs for preparation of the Units for the additional period of operation.

3 Composing a list of MCS subject to examination; Elaboration of detailed programs for complex examination of the electrical equipment; Elaboration of detailed programs for complex examination of the MCS equipment; Elaboration of reports on the complex examination of the electrical equipment of Kozloduy NPP Units 5&6; Elaboration of reports on the complex examination of the MCS equipment of Kozloduy NPP Units 5&6; Participation in preparation and concurrence of a Summary report; Participation in preparation and concurrence of a Program for prolongation of the Kozloduy NPP Units Operation Lifetime.

4 Criterion 1 Safety related Structures, Systems and Components (SSC), which maintain their functional characteristics in case of postulated initiating events, for maintaining the coolant circuit integrity, for possibility of reactor shutdown and its maintaining in safe shutdown state, for capability of preventing accidents or mitigating the consequences thereof. Criterion 2 SSC, which do not have influence on the safety, but whose failure could become obstacle for other SSC, which are safety related, in performing their safety functions. Criterion 3 SSC, which do not have influence on the safety, but must provide for functions to be performed in the prolonged period of operation, in case of activating the reactor scram, and in case of total blackout.

5 Criterion 4 SSC, which do not have influence on the safety, but must provide for functions to be performed in the prolonged period of operation, according to the requirements on fire safety and environment protection. Criterion 5 Unit-common and Plant-common SSC, required for sustainable generation of electricity during the additional period of operation.

6 Scope of the examined equipment within the scope of the complex examination of MCS: Neutron flux monitoring system; Automatic power controller/power limiting controller; Emergency Protection system /Warning Protection system; Control Rod Drive Control System; System for radiation monitoring and dosimetric control; System for critical parameters monitoring; System for automatic monitoring of the additional bundles prestressing/system for automatic monitoring of the standard bundles prestressing ; Main control room panels; Wild range reactor body temperature control;

7 Temperature monitoring at the fuel assemblies exit; Unit information system; Turbine control automated system; Monitoring and control Ovation system of primary and secondary circuit; Containment post accident monitoring system; Ventilation pipes radiation monitoring system; Hydrogen recombination system; Cold overpressure protection system; Filtered pressure relief system; Coolant level monitoring system.

8 Equipment within the scope of complex examination of the electrical equipment: Unit main transformers; House loads Transformers; Switchgear 0,4 kv from SS; Transformers 6/0.4 kv of SS; Accumulator batteries in the main building; Synchronous generators of DGS 1, 2 and 3; Switchgear 0,4 kv from DGS 1, 2 and 3; Pumps electric motors 6kV; Mobile Diesel Generators 0.4kV; Mobile Diesel Generator 6 kv;

9 Generator breaker; Uninterrupted power supply (UPS) system - ABP10, 20, 30, 40; Switchgear 6 kv from SS; Diesel generators -1, 2, 3 Electrical equipment; Fire detectors; Fire alarm stations; Distribution boards for fire dampers.

10 The main activities on determining the current state and assessment of the residual lifetime of the Electrical equipment and MCS components of Kozloduy NPP Units 5&6 have been performed in accordance with: Program for complex examination of the actual state and assessment of the residual lifetime of the monitoring and control systems (MCS) of Kozloduy NPP Unit 5, RP ATE.116/ ; Program for complex examination of the actual state and assessment of the residual lifetime of the monitoring and control systems (MCS) of Kozloduy NPP Unit 6, RP ATE.116/ ; Program for complex examination of the actual state and assessment of the residual lifetime of the electrical equipment (EEq) of Kozloduy NPP Unit 5, RP ATE.116/ ; Program for complex examination of the actual state and assessment of the residual lifetime of the electrical equipment (EEq) of Kozloduy NPP Unit 6, RP ATE.116/

11 The activities performed in the process of the complex examination are as follows: Compiling a list of the components; Gathering, review and analysis of input data on the systems and components within the scope; Assessment of the current state of the components; Quantitative assessment of the residual lifetime; Composing a list with recommendations.

12 The results of all performed activities have been summarized in the so-called examination sheets. Such sheets have been filled out for each group of components of the same type, and they contain all available information on each component. On the basis of all performed analyses and review of the operation and manufacturer documentation, recommendations for each component have been prepared. Each recommendation has its unique code, whereby for each component, based on the performed analyses and obtained results, respective measures are envisaged. А replacement of SSC; B modernization of SSC; C performing additional work on assessment of the residual lifetime; D radiochemistry management within the frames of the Technical Maintenance and Repairs; E radiochemistry management by changing the operation modes during the additional period of lifetime prolongation; F no further actions are required (SSC possess sufficient service life capacity for the additional period of operation).

13 Based on the performed analysis, the following conclusions have been made: In Kozloduy NPP are maintained optimal conditions for functioning of the electrical equipment and MCS equipment; As a whole, the technical state of the equipment is in compliance with the design and operation requirement; The Technical Maintenance and Repairs (TM&R) programs fully comply with the requirements of the design documentation and manufacturers; The results of the quantitative assessment of the residual lifetime confirm that most of the equipment is capable of functioning beyond the design period of operation as prescribed by the manufacturers, under the appropriate operation conditions; nevertheless, in the examination, for determining the residual lifetime, conservative approach has been adopted.

14 The final result of all performed activities is compilation of lists, thereby summarizing the necessary activities with respect to the equipment for prolongation of the operation lifetime of Kozloduy NPP Units 5&6. In general, the following lists have been composed: List of the elements which are to be replaced or modernized; List of the elements for which it is required to perform additional work on examination and justification of the residual lifetime by special methodologies and/or programs; List of the elements whose technical state and service life characteristics may be rehabilitated of prolonged by technical maintenance and repair (TM&R); List of the elements possessing residual lifetime capacity, whose operation may be prolonged for certain period.

15 Results of the examination of the MCS equipment for Kozloduy NPP Unit ТОиР TM&R Определен Certain period период Additional Допълнително обследване examination Замяна Replacement Total quantity of examined components 528 nos.

16 Results of the examination of the MCS equipment for Kozloduy NPP Unit TM&R ТОиР Определен период Certain period Допълнително обследване Additional examination 125 Замяна Replacement Total of examined components 529 nos.

17 Results of the examination of the electrical equipment for Kozloduy NPP Unit ТОиР TM&R 340 Определен период Certain period Допълнително Additional обследване examination Total of examined components 514 nos.

18 Results of the examination of the electrical equipment for Kozloduy NPP Unit ТОиР TM&R 338 Определен период Certain period Допълнително Additional обследване examination Total of examined components 514 nos.

19 In conclusion, it could be stated that out of the total of 1042 examined components of Kozloduy NPP Unit 5, for 84 additional investigations must be carried out according to special methodologies and/or programs, 216 components must be replaced. All these components are included in the PROGRAM FOR PREPARATION OF KOZLODUY NPP UNIT 5 FOR ADDITIONAL PERIOD OF OPERATION, PM АТЕ.116/ For Unit 6 the quantity of examined components of MCS and Electrical Equipment is 1043, whereby, for 133 thereof, additional examinations must be carried out according to special methodologies and/or programs, and 215 must be replaced during the preparation of the Unit for the Additional period of operation (APO); they are included in the PROGRAM FOR PREPARATION OF KOZLODUY NPP UNIT 6 FOR ADDITIONAL PERIOD OF OPERATION, PM АТЕ.116/