China National Nuclear Corporation (CNNC) has reported that all three ZH-65 steam generators (SGs) have been installed for the Hualong One reactor at unit 2 of the Zhangzhou NPP in Fujian province. The SG installation took five-days and the lifting into place of the second steam generator took just 2 hours and 54 minutes, "setting a new record in the history of nuclear power".

At Zhangzhou NPP, two Chinese-designed Hualong One reactors are under construction. China's Ministry of Ecology and Environment issued construction licences for Zhangzhou 1&2 in 2019 to CNNC-Guodian Zhangzhou Energy Company, the owner of the Zhangzhou NPP, which was established in 2011. It is owned by CNNC (51%) and China Guodian Corporation (49%). The licences are valid for 10 years. The units are scheduled to begin commercial operation in 2024 and 2025.

CNNC said the ZH-65 SG is the first domestic third-generation nuclear power steam generator with completely independent intellectual property rights in China. All six SGs were installed at units 1&2 using the "main equipment first-introduction method", also known as the open top method. This involves a large crawler crane lifting the main equipment into the reactor building before the dome is put in place.

"Compared with the conventional method, the time spent waiting for the availability of the polar crane on the critical path of the main circuit is saved, so that the installation work of the main circuit can be started in advance, which can greatly reduce the construction period," CNNC said.

This year the main equipment of Zhangzhou 2 will be installed using improved methods based on the experience gained at unit 1. New technological methods such as modularisation of steel cages is being implemented, and a number of technical solutions have been improved and upgraded, including the overall planning of large-scale lifting arrangements for the entire site, CNNC noted. “The hoisting has laid a solid foundation and provided a strong demonstration practice and technical support for batch construction of the Hualong One,” it added.

Image: One of the three steam generators is hoisted into the reactor building of Zhangzhou 2 (photo courtesy of CNNC)