IIW White Paper

9 Needs and challenges of major industry sectors for future applications

both globally and for specific countries. A nuclear reactor is far more environmentally friendly as compared to fossil power generating station, as it does not emit any potentially hazardous, green house gases such as CO 2 , SO 2 and oxides of nitrogen. Nuclear power can be generated using both the fusion and fission reactions, of which the fission based nuclear technology is well established. On the other hand, fusion which offers limitless power resources, needs to overcome several challenges related to materials and associated technologies, in order to become commercially viable. For the sustained growth of nuclear energy, it is important to ensure that the cost of nuclear energy production is economical, as compared to other energy resources. For this purpose, research in welding technology is vital for the sustainable development of nuclear energy. Welding is a manufacturing process that is critical for the successful construction and safe operation of nuclear power plants. With the prevalence of fabricated metallic components, such as pressure vessels, pipe work, liners and cable trays, the scale of the welding task is very large for both onsite and offsite fabrication. For example, on the Olkiluoto EPR (French Nuclear reactor of 3d generation) build project there are approximately 200 km of piping and about 30,000 welds within the nuclear island alone. Industry and other stakeholders must be confident of the quality and integrity of welded joints, particularly as the next generation of nuclear power plants is expected to have a design life of at least 60 years. Ensuring welding quality is challenging and can be costly. Most often it is examined in the finished product and, in instances where quality criteria are not met, costly and time-consuming repair and rework can result. Approaches used in other industries that address quality assurance in the welding process may be applicable to the nuclear sector. Two sets of rules are in useworldwidewhich apply to nuclear pressurised components. In the nuclear industry these rules are published by American Society of Mechanical Engineers (ASME) and French Association for the rules governing the Design, Construction and Operating Supervision of the Equipment Items for Electro Nuclear Boilers (AFCEN). ASME The fabrication and the installation of structures must meet the ASME Boiler and Pressure Vessel Code section III, and then once completed, the continuous in-service inspection and repair activities must meet Section X1 of the same code. The ASME standard for Quality Assurance Requirements for Nuclear Facility Applications (QA) - NQA-1 (2004) provides supplemental information and contract requirements. This standard provides guidance andmethods for defining a quality system that wouldmeet the US legislative requirements. It is also a globally recognised quality standard that organisations planning construction to the ASME code may want to adopt. This standard reflects industry experience and current understanding of the quality assurance requirements. The RCC and ETC approach The Rules for Design and Construction (RCC) family and EPR Technical Code (ETCs) are design and construction or technical codes and standards corresponding to industrial practice implemented in the design, construction and commissioning of the 3 rd generation EPR reactor. The last upgrade of RCC-M takes into account the EU standards referenced in all chapters to ensure consistency with EU requirements, and to meet recognised international standards. RCC-M requires product and shop qualification and also prototype qualifications. As with ASME, NQA-1 RCC-M Section 1 specifies broad quality assurance and quality management requirements based on the ISO 9001 requirements. Both codes have significant implications for welding quality and integrity.

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Through Optimum Use and Innovation of Welding and Joining Technologies

Improving Global Quality of Life