Quality Defects Will Delay This Nuclear Unit's Startup
David Wagman | July 26, 2018The Flamanville nuclear station on France's Normandy Coast. Source: EDF
Utility EDF says that fuel loading at the Flamanville nuclear plant under construction in France will now take place in the fourth quarter of 2019, a delay from the fourth quarter of 2018.
It also says that the cost of the 1,650-megawatt pressurized water reactor (PWR) has risen from $12.3 billion to $12.7 billion.
Welding defects in a system that directs steam produced in the plant's steam generators to its turbine were detected in March during a required regulatory inspection. The inspection included an examination of the welds in the plant's primary and secondary systems, and sets a baseline condition of the plant before it begins operating.
The utility went on to inspect 150 welds and found that 33 have quality deficiencies that need to be repaired. Another 20 welds will be redone, even though they do not have any defects, as they fall short of quality goals set by the utility. For 10 other welds, EDF submitted a proposal to regulators detailing a specific justification method to ensure safety through the plant's operating life. The remaining 85 welds are compliant, the utility says.
To account for the weld inspections and repairs, EDF revised its startup schedule. World Nuclear News says that hot functional tests — which involve checking the equipment under similar temperature and pressure conditions to those under which it will operate — had been due to start in July. Those test will now begin later in 2018. Fuel loading into the unit's core is now expected in late 2019 instead of late 2018.
Construction of the Flamanville EPR began in December 2007, with commercial operation originally expected in 2013.
"... The utility went on to inspect 150 welds..."
...which resulted in more than 1/3 being slated to be redone.
That is a very high rate of unacceptable work. Problems with welds should be caught and corrected as the fabrication is progressing. It seems like this could be indicative of more widespread problems.
I doubt there are only 150 welds in the entire primary and secondary. Those also aren't likely to be the only place where weld quality is of critical importance.
Sounds like further inspection might be called for.