Cracks of several centimeters were found in all four feedwater pumps of the Finnish Olkiluoto 3 power plant. Operator Teollisuuden Voima Oyj (TVO) said he does not yet know what impact it will have on the plant’s commissioning schedule.
The TVO company announced that during maintenance and inspection damage was found to the internal parts of the feedwater pumps located on the turbine island of the plant.
The Olkiluoto nuclear power plant is one of two Finnish nuclear power plants. It is located on the island of Olkiluoto in the Gulf of Bothnia, about 25 km north of the city of Rauma. The power plant operates three nuclear reactors. The Onkalo radioactive waste repository is located near the power plant.
Feedwater pumps are the largest pumps at the Olkiluoto 3 power plant and are used to pump water from the feedwater tank to the steam generators. TVO said the cracks found on the pumps have no effect on nuclear safety.
The company noted that the design of the feed water pumps located on the turbine island of the Olkiluoto 3 power plant is commonly used in power plants. However, the pumps in OL3 have been designed for operation in power plants and are larger in size.
“The investigation is currently ongoing in several labs,” TVO now said. “The root cause of the cracks found on the pump impellers is still unknown,” the energy company noted.
The OL3 power plant was built by the Areva-Siemens consortium with a turnkey contract at a fixed price. It is jointly responsible for contractual obligations until the end of the blocking guarantee period. Construction of OL3 began in 2005, with the completion of the reactor initially scheduled for 2009, but the project suffered various delays and complications.
OL3 reached criticality for the first time on December 21 last year and was connected to the grid on March 12. The 1600 MWe pressurized water reactor is currently in the trial production phase. It was started at full capacity for the first time in late September and is currently expected to start regular electricity production in December.
“The timetable for the continuation of the trial production program will be updated once the causes of the damage and the method of repair are confirmed,” said TVO.
(nik)
