The RPV ageing management documentation system used for Qinshan phase 1 is shown in Fig. 61. At the centre in yellow is the PDCA cycle, a systematic approach to ageing management spearheaded by the IAEA.
Beginning with the planning phase, the AMP coordination group, after receiving feedback from the field and from operating experience, and after building a sufficient understanding of all RPV degradation mechanisms, develops
Examination of research results related to the degradation of the operating system to
obtain understanding
Survey options based on the R&D results
Examination of applicable procedures and measures
Appropriate study needed?
Document study results the resulting process justifying the engineered solution
Start
SupplementaryInformation derived
NO Further studies
required?
Adequate
PSR Documented YES
YES
NO NO
FIG. 60. Procedure to incorporate research and development findings into the PSR documentation.
box to the right, applies the nuclear power plant procedures and ensures that water chemistry is correctly managed.
The yellow box at the bottom, representing the group in charge of the ‘CHECK’ step, manages the inspection, the monitoring, the surveillance programme and the condition assessment and sends its output to the operation feedback system. For the ‘ACT’ step, the yellow box to the left represents the group in charge of the mitigation and maintenance aspects.
Figure 62 shows the ageing management activities and the milestone achievements since 2009 in the Chinese plants of Daya Bay and Ling Ao.
The pyramidal process begins at the top with a screening of all SSCs significant to safety, reliability and electricity production in the nuclear power plant.
The SSCs that are non-significant to safety, reliability and production can be run to failure if they seldom require maintenance and they can be replaced easily without shutting down the plant. If, on the other hand, their operability can be ensured through regular maintenance, a simple, periodic maintenance schedule is all they require.
The SSCs that are significant to safety, reliability and electricity production are under a major AMP or are replaced within the operating lifespan. Of these, the SSCs without a clear AMP or replacement plan require topical R&D and the development of a life cycle management programme. The critical SSCs with a major AMP can have their life cycle management simply scheduled for implementation.
Figure 63 represents the generic process, common to all nuclear power plants in China, for preparation,
Understanding ageing degradation AMP coordination
Operation
Checking, monitoring and assessment Mitigation and
maintenance
RPV AMP procedure
PLAN
ACT DO
CHECK
Hydrochemistry management Ageing management
system for RPV
Procedure of NPP
Operation monitoring and
analysis management
system Proc. of chemistry
monitoring management
Refrigerant leaking of RPV
Proc. of operation record management
Core monitoring management
system
Transient statistic for RPV Monitoring
management
Assessment management Inspection
management
Operation experience feedback
system Procedure of
monitoring checking and test for Qinshan 1 NPP System for
alteration management of system equipment RPV material
irradiation monitoring program
for Qinshan 1 NPP Service
inspection management
system Service inspection
programmefor Qinshan1 NPP Procedure of teardown and instalment of RPV
closure head Rule of maintenance and
repair for RPV
Proc. Of mitigation and
maintenance
FIG. 61. RPV ageing management documentation system for Qinshan phase 1, China.
for nuclear power plants. As a starting point, the nuclear power plant owner/operator, as the licensee, submits the PSR plan that includes the scope, the specific requirements and the deliverables to the regulator for approval. The activities included in the submission are those requested by the regulatory body and those coming from the owner’s own plant diagnostics and corrective action plan. The PSR ends with the regulatory approval of the PSR corrective action plan.
All SSCs in NPP
SSCs significant to safety,
reliability and economy SSCs nonsignificant to safety, reliability and economy
SSCs no major maintenance or replacement plan
SSCs plan to major maintenance or
replacement
SSCs operability can be ensured through normal maintenance
SSCs seldom need maintenance or can be replaced easily Significant to safety
reliability and economy?
Can be operated till occurring of failure?
Plan to major maintenance or replacement within design life?
Level A Level B Level C Level D
Y N
N Y
N Y
Need topical R&D on LCM Need LCM Schedule Need LCM Schedule No need LCM FIG. 62. Screening, life cycle management and preventive maintenance activities in Daya Bay and Ling Ao nuclear power plants, China. LCM — life cycle management.
Operator Submits PSR Plan to NNSA for approval.
The PSR plan should stipulate general scope, specific requirements and deliverables of PSR.
Preparation of PSR Implementation of PSR Plan of corrective action and/or safety improvement
Activities of safety regulatory
body
The corrective actions plan being approved by NNSA
PSR start point
PSR implementation step by step
PSR end point
FIG. 63. Generic flow chart for PSRs in Chinese nuclear power plants. NNSA — National Nuclear Safety Administration.