August 25, 2021
The bridge of the polar crane for Unit 1 of the Zhangzhou nuclear power plant in the Chinese province of Fujian was brought into position near the top of the Hualong One reactor building. For the first time in China, the components of the bridge were not lifted individually but as a whole. Sitting on a circular rail, the crane can rotate 360 degrees and is used to lift reactor components and main pump components.
Installation of the bridge of the polar crane in Zhangzhou Block 1 (Image: CNNC)
The 45.5 meter long, 15.2 meter wide, 8.37 meter high and around 418 tonne component was lifted into place on August 24th with a 3200 tonne crawler crane.
China National Nuclear Corporation (CNNC) noted that this was the first time the bridge and its components have been installed in China as a whole. So far, the various components of polar cranes for data measurements have been assembled on the ground before they are dismantled, lifted separately and reassembled. At the bridge for Zhangzhou 1, the electric, non-electric, end girders, horizontal wheels, rotating mechanism and other components were assembled on the ground and then lifted as a whole.
“The use of a new installation technology simplifies the tedious dismantling and assembly process of segmented hoists, which significantly improves construction efficiency,” said CNNC. It found that the new procedure reduced the time it took to install the polar crane by 15 days.
Polar cranes are used in pressurized water reactors to lift reactor vessel lids, internals, and a variety of lighter loads in the event of refueling failures. In some plants, the polar crane is also used to lift the reactor vessel itself and the steam generator during construction.
CNNC said the installation of the polar crane would “lay a solid foundation for the later introduction of the main equipment and the lifting of the inner dome”.
In May 2014, the local government approved Phase I of the Zhangzhou plant, which consists of two AP1000 units. The National Nuclear Safety Administration approved the blocks in December 2015 and confirmed the site selection in October 2016. Construction of Phase I was originally scheduled to begin in May 2017. However, CNNC later decided to use the Hualong One design instead. Two more units are planned for Phase II of the facility and two more are proposed for Phase III.
China’s Ministry of Ecology and Environment granted CNNC-Guodian Zhangzhou Energy Company, the owner of that of CNNC (51%) and China Guodian Corporation (49%) in 2011, on October 9, 2019. Construction of Unit 1 began a week later, that of block 2 in September 2020. Commercial operation of the blocks is planned for 2024 and 2025 respectively.
Researched and written by World Nuclear News
