The two-part tests confirm that the containment vessel meets design and construction quality requirements. The first part - the structural integrity test - involved the vessel being pressurised and monitored to confirm that its design and construction meet all applicable industry codes and standards at 110% of design pressure.
The vessel was then pressurised to design pressure (0.420 MPa) and the integrated leak rate test was performed to demonstrate its ability to prevent the release of radioactive materials in the event of an emergency.
During the containment pressure test, the containment leakage is checked through the acoustic leak detection test, and the changes in the containment structure performance are monitored through internal visual inspection and external visual inspection tests.
The tests were successfully completed on 20 June, China National Nuclear Corporation (CNNC) subsidiary China Nuclear Industry 23 Construction Company Limited (CNI23) announced.
China's Ministry of Ecology and Environment issued construction licences for Zhangzhou units 1 and 2 on 9 October 2019 to CNNC-Guodian Zhangzhou Energy Company, the owner of the Zhangzhou nuclear power project, which was created by CNNC (51%) and China Guodian Corporation (49%) in 2011. Construction of unit 1 began one week after the issuance of the construction licence, with that of unit 2 starting in September 2020.
"According to the plan, unit 1 will generate electricity within the year, which will drive the economic and social development of southern Fujian and serve as a new development engine for the region to achieve carbon peak and carbon neutrality goals," CNNC said last month. It noted that preparations are currently under way for cold functional tests at unit 2.
In September 2022, China's State Council approved the construction of two further Hualong One units as Phase II of the Zhangzhou plant. First concrete for the nuclear island of unit 3 was poured on 22 February this year. CNNC said first concrete for unit 4 is expected "within the year".