The four reactor coolant pumps at unit 1 of the Haiyang nuclear power plant in China's Shandong province have been operated simultaneously at full speed for the first time. The AP1000 is set to begin operating by the end of the year.
|Operators in Haiyang 1's control room test the main pumps (Image: SNPTC)
The four pumps all attained 100% speed at 1.23am on 9 October, State Nuclear Power Technology Corporation (SNPTC) announced in a 12 October statement.
Installation of the fourth and final reactor coolant pump at the Haiyang 1 AP1000 was completed on 25 April. Cold hydrostatic tests of the primary circuit were successfully completed at Haiyang 1 on 2 July. The tests, which involve increasing the pressure within the primary circuit to 21.6 MPa and maintaining it at that level for 11 minutes, aimed to confirm the integrity and sealing of the circuit's components.
Hot tests of the reactor's primary circuit were officially launched on 20 September. Tests have subsequently been carried out with the pumps operating at 24%, 50% and 88% speed. On 9 October, all the pumps were operated at full-speed for two hours with the water in the reactor coolant system at a temperature of around 275°C. The pumps were then taken back down to 50% speed.
SNPTC said during the tests the pumps operated as normal, "verifying their reliability and stability".
In September 2007, Westinghouse and its partners the Shaw Group received authorization to construct four AP1000 units in China: two at Sanmen in Zhejiang province and two more at Haiyang.
Sanmen unit 1 is expected to be the first AP1000 to begin operating later this year, while Haiyang 1 is also expected to start up by the end of the year.
SNPTC announced last month that the four main pumps at Sanmen 1 had been operated continuously at full speed for five hours as part of the unit's start-up. The company said that, at full-speed, the pumps' vibration, stator temperature and bearing temperature were within the normal range.
Four AP1000 reactors are being built in the USA - two each at Vogtle and Summer - while three AP1000s are also proposed for the Moorside site in the UK.
Researched and written
by World Nuclear News