Cold testing under way at Chinese Hualong One unit

29 April 2019

Cold hydrostatic testing has begun at unit 5 of the Fuqing nuclear power plant in China's Fujian province, the first of two demonstration Hualong One reactors under construction at the site. The tests mark the first time the reactor systems are operated together with the auxiliary systems.

Plant workers together with representatives from the general contractor and nuclear regulator celebrate the start of cold tests at Fuqing 5 in its control room (Image: China Nuclear Industry 23 Construction Co Ltd)

Cold functional tests are carried out to confirm whether components and systems important to safety are properly installed and ready to operate in a cold condition. The main purpose of these tests is to verify the leak-tightness of the primary circuit and components - such as pressure vessels, pipelines and valves of both the nuclear and conventional islands - and to clean the main circulation pipes.

The tests at Fuqing 5 began on 27 April. China National Nuclear Corporation (CNNC) said this was 50 days ahead of schedule and marks the transition of the unit from the installation phase to the commissioning phase.

During tests, inspections of the reactor systems will be carried out at water pressure levels of 2.7 MPa, 7.0 MPa, 10.0 MPa, 15.4 MPa, 16.5 MPa, 17.13 MPa and 22.3 MPa. Tests at 2.7 MPa were completed at 2:36am on 28 April.

In November 2014, CNNC announced that the fifth and sixth units at Fuqing will use the domestically-developed Hualong One pressurised water reactor design, marking its first deployment. The company had previously expected to use the ACP1000 design for those units, but plans were revised in line with a re-organisation of the Chinese nuclear industry. China's State Council gave final approval for construction of Fuqing units 5 and 6 in April 2015.

The pouring of first concrete for Fuqing 5 began in May that year, marking the official start of construction of the unit. Construction of unit 6 began in December the same year. The dome of unit 5 was installed on the containment building in May 2017 and the reactor pressure vessel was installed in January last year. Installation of the third and final main reactor coolant pump at Fuqing 5 was completed on 5 January this year.

Fuqing 5 and 6 are scheduled to be completed in 2019 and 2020, respectively.

Construction of two Hualong One (HPR1000) units is also under way at China General Nuclear's Fangchenggang plant in the Guangxi Autonomous Region. Those units are also expected to start up in 2019 and 2020. Two HPR1000 units are under construction at Pakistan's Karachi nuclear power plant. Construction began on Karachi unit 2 in 2015 and unit 3 in 2016; the units are planned to enter commercial operation in 2021 and 2022. The HPR1000 has also been proposed for construction at Bradwell in the UK, where it is undergoing Generic Design Assessment.

Researched and written by World Nuclear News