Nuclear safety research

Specific projects are undertaken for individual generating utilities and the UK's nuclear regulator, the Nuclear Installations Inspectorate. Many projects relate to the structural integrity of plant components and systems of Magnox, AGR and pressurised water reactors.

The range of projects undertaken is wide and covers the fields of structural analysis, materials, and non-destructive testing. Recent examples include the assessment of flaws around penetrations and attachments and in mismatched welds, a study of the root causes of pressure vessel failures and the development of a model to predict reheat crack growth in high temperature plant. TWI's unique wide-plate testing facilities have been exploited in major programmes of work on fracture and crack arrest.

In the field of non-destructive testing, the capability of radiography to detect defects in thick section welds (> 25mm) was tested in a series of projects over several years. The work continues to examine the capability of radiography to detect defects in thinner sections. Other projects have identified the best NDT techniques to detect cracks in fillet welds and have developed improved analytical methods for sizing rough defects. New research is assessing the potential application of phased array inspection to nuclear plant components.

TWI is also active in collaborative projects and networks supported by the European Commission's framework research programmes in nuclear fission safety. Recent international projects include validating residual stress in ageing components (VORSAC) and contributions to studies on the integrity of bi-metallic and dissimilar metal welds (BIMET and ADIMEW). Participation in European structural integrity networks such as the Network for Evaluating Structural Components (NESC) and the European Network for Inspection Qualification (ENIQ) keeps TWI at the forefront of evolving technology and engenders co-operation with a wide range of member companies in the nuclear sector.

TWI is keen to build on its reputation for high quality research and expand its existing client base. Technical expertise and capability extends widely across the fields of structural integrity, NDT, materials and joining process development and evaluation.

Contact us at: power@twi.co.uk