Nuclear expertise, developed by TWI over the last half century, has recently been called upon by a major nuclear operator.
Atomic Energy of Canada Limited (AECL) is collaborating closely with third-party welding experts The Welding Institute (TWI), UK based global specialists in materials joining technology on a highly specialised repair to an aluminium reactor vessel. TWI is helping with the development and testing of welding techniques in what AECL describes as a unique and challenging environment.
The NRU reactor is responsible for producing approximately 30% of the global supply of medical isotopes, used for radiotherapy and other medical treatments. There is virtually no published data on welding of irradiated aluminium, and TWI has been instrumental in advising AECL on development of the specialised repair techniques required for this task.
The first weld build-up inside the NRU reactor vessel was successfully performed on December 12th 2009. The weld repair was conducted remotely by operating the welding equipment from a position of approximately 10 metres above the location of the repair site.
Non-destructive examinations of the weld found no defects, and preparations are now underway to conduct further repairs.