The investigation is still ongoing regarding the damages in the internals of Olkiluoto 3’s feedwater pumps
Damage was detected in the internals of the feedwater pumps located in Olkiluoto 3’s turbine island a week ago. The investigation is currently ongoing in several laboratories. The schedule for continuing the test production programme will be updated once the reasons for the damage and the repair method have been confirmed.
Cracks of a few centimetres have been identified in all four of OL3’s feedwater pumps. The root cause of the cracks found in the pump impellers is still unknown. The cracks were detected during maintenance and inspection work.
The structure of the feedwater pumps located in Olkiluoto 3’s turbine island is commonly used in power plants. However, the pumps at Olkiluoto 3 have been designed for the plant unit's operations and are larger in size. The feedwater pumps are Olkiluoto 3’s largest pumps, and they are used to pump water from the feedwater tank into the steam generators. The cracks detected at the pumps have no impact on nuclear safety.
The possible schedule impact will be communicated as soon as the results of the investigation are available.