NESC - Network for the Evaluation of Steel Components

The objective of the Network for the Evaluation of Steel Components (NESC) is to provide a framework for the execution of large structural integrity projects within a network, operated by the Commission's Joint Research Centre (Institute for Advanced Materials), and comprising...

The objective of the Network for the Evaluation of Steel Components (NESC) is to provide a framework for the execution of large structural integrity projects within a network, operated by the Commission's Joint Research Centre (Institute for Advanced Materials), and comprising more than 30 organizations from 13 countries worldwide.

Launched in 1993, the first project, NESC I, has addressed all the crucial aspects of structural integrity assessment of nuclear reactor clad pressure vessel (PV) steels under PTS (Pressurised Thermal Shock) emergency shut down conditions. In particular, "Task Groups" have been established for:

- The inspection of defects using eight nationally approved in-service inspection techniques;
- The evaluation of a complete set of physical and mechanical material properties;
- The assessment of fracture behaviour by 16 international fracture mechanics experts;
- The development of the complex instrumentation of the simulation test vessel to facilitate the detection of failure.

A landmark in the project was reached on 20 March 1997 when the vessel successfully underwent its planned test in the AEA Technology spinning cylinder test facility, sited at Risley, UK. Over the next 18 months, the full evaluation of the project is expected to lead to improvements in the ability to detect and size defects in clad PV steels, to accurately characterize aged material properties, to predict the response of damaged structures, to ensure enhanced safety margins for operating plants and, finally, to contribute improved accuracy to design codes and standards.

The JRC's Institute for Advanced Materials (Petten) has provided the hub of operating agent, network management and reference laboratory around which the NESC I project has revolved. It is currently in the process of evaluating equally important candidate structural integrity projects which will be launched as new NESC projects in the near future.