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Hot testing of Tianwan 6 begins

Tests that simulate the temperatures and pressures which the reactor systems will be subjected to during normal operation have started at unit 6 of the Tianwan nuclear power plant in China’s Jiangsu province. The ACPR1000 reactor is scheduled to enter commercial operation by the end of 2021.


Hot functional testing of Tianwan 6 began on 28 November, China Nuclear Engineering and Construction Corporation (CNECC) announced. CNECC is a subsidiary of China National Nuclear Corporation (CNNC). It described the tests as a “dress rehearsal” before the reactor is loaded with nuclear fuel and started up.

Hot tests involve increasing the temperature of the reactor coolant system and carrying out comprehensive tests to ensure that coolant circuits and safety systems are operating as they should. Carried out before the loading of nuclear fuel, such testing simulates the thermal working conditions of the power plant and verifies that nuclear island and conventional equipment and systems meet design requirements.

Cold functional tests – which are carried out to confirm whether components and systems important to safety are properly installed and ready to operate in a cold condition – were completed at Tianwan 6 on 4 October. The main purpose of those tests was to verify the leak-tightness of the primary circuit.

Units 5 and 6 at Tianwan – Tianwan Phase III – both feature ACPR1000 reactors. First safety-related concrete was poured for unit 5 on 27 December 2015, with that for unit 6 poured on 7 September 2016. Tianwan 5 entered commercial operation in September this year, with unit 6 expected to follow by the end of next year.

The first four units at the site – which began commercial operation between June 2007 and December 2018 – are Gidropress VVER units supplied by Russia, as will be the seventh and eighth, for which a general contract was signed in March.

When all eight units are in operation Tianwan would become the largest nuclear power plant in the world with eight units and a total generating capacity of about 8100 MWe.

The Tianwan plant is owned and operated by Jiangsu Nuclear Power Corporation, a joint venture between CNNC (50%), China Power Investment Corporation (30%) and Jiangsu Guoxin Group (20%).

Source: World Nuclear News