CWA 18008:2023

Design and Construction Code for mechanical equipments of innovative nuclear installations CWA 18008:2023

Scope

Taking the RCC E, RCC M, RCC MRx and RCC CW AFCEN codes as a starting point, CEN/WS 64 III undertook to explore a generic pattern to “Europeanize” the codes so that they could be adopted for any nuclear project in the EU, primarily for new builds but also potentially for improvement and life extension of existing nuclear facilities. The domains covered by CEN/WS 64 III included mechanical equipment for Gen II and III; mechanical equipment for GEN IV reactors, civil works and Electrical equipment for all kind of nuclear facilities. The work was organized accordingly and undertaken by three CEN/WS 64 III working groups, namely PG1 (mechanical equipment for GEN II-III reactors), PG2 (mechanical equipment for GEN IV reactors), PG3 (civil works) and PG 4 (Electrical equipment).
For the Code Evolution proposals, CEN/WS 64 III adopted an interactive process with AFCEN, as follows:
• Elaborating code evolution recommendations through technical debates within expert groups, in consideration of cases not currently taken into account in the codes, such as the integration of new materials or practices or designs and improvements of safety, etc. or methodology.
• Submitting these recommendations to AFCEN for review in the framework of its specialised subcommittees and evaluation of the feasibility (including time required) of their being taken into account in the codes. On this basis, AFCEN gives a formal answer to the Workshop on its recommendations.
• Evaluating the answers made by AFCEN.

Prior to the implementation of the process, a phase of code knowledge attainments for the experts was scheduled in the CEN/WS 64 III business plan. Consequently, the whole process duration became properly understood and was planned accordingly.
In addition to this code evolution process and as already indicated, CEN/WS 64/ Phase III intended to identify possible R&D programmes of generic concern in support of the recommended evolutions, thereafter transmitting the proposals to EC Directorate General Research and Innovation (DG RTD) with a view to their being incorporated into the EURATOM R&D Work Programmes.

CEN/WS 64 III was primarily conceived to address medium and long term code evolutions and the associated R&D needs. However, the possibility to propose direct code amendments or extensions, as well as R&D projects, was open and provided the opportunity to address short or medium term needs as well.
A large number of topics have been addressed, including plant life management (PLM) and design for long-term operation (LTO), environmental degradation mechanism and guidelines for quality assurance.

Some recommendations for code modifications have been proposed by CEN/WS 64 III to
AFCEN. These have been and/or continue to be examined by AFCEN and responses have been communicated accordingly.

This CWA compiles medium and long term recommendations for the evolution of the codes taken as pilot cases, namely RCC M, RCC MRx and RCC CW, as well as associated R&D needs.
The CWA was subject to the usual review and balloting procedures, the results and comments of which are included as an appendix.
The CWA is completed with comments and appreciation by the Chairman, the Vice-Chairman and the conveners of the working groups on the work done and the role of AFCEN, noting that the late recommendations that could not be submitted to AFCEN or to which AFCEN has not had sufficient time to answer are included.