China Nuclear Power Engineering Company (CNPE) said tests were completed on 20 July to evaluate the strength and leak tightness of the inner containment of unit 6 at the Fuqing NPP in Fujian province. A total of 16 commissioning tests were completed which involved raising and reducing the pressure inside the containment in 14 stages. Fuqing 6 is the second of two demonstration Hualong One (HPR1000) reactors being built at the site and is scheduled to begin operations by the end of the year.
The structural integrity and integrated leak rate tests began on 11 July. CNPE is the China National Nuclear Corporation (CNNC) subsidiary responsible for NPP construction, equipment procurement, trial testing and operational maintenance. The structural integrity test evaluates the strength of the reactor containment building by pressurising and depressurising it to simulate a variety of conditions, while the leak rate test evaluates leak tightness under different conditions. CNPE said the test results show the building, which houses the reactor and major components, can perform its primary function of containing radiation under normal operating conditions as well as in emergencies or other extraordinary events.
"Through the verification of the commissioning test at each stage, the structural strength and overall sealing performance of the inner containment all meet the design requirements, laying a solid foundation for the subsequent loading of fuel into Fuqing nuclear power plant unit 6," the company said.
First concrete for Fuqing 5 was poured in May 2015 and for unit 6 the following. Unit 5 achieved first criticality in October 2020 and was connected to the grid in November, beginning commercial operation in January 2021. Cold functional testing was completed at Fuqing 6 in January.
CNNC has also begun construction of two Hualong One units at the Zhangzhou plant in Fujian province, as well as the first of two units at Taipingling NPP in Guangdong. Two demonstration Hualong One units are also under construction at China General Nuclear's Fangchenggang plant in the Guangxi Autonomous Region for start up in 2022.