Non-pressure tests representing a landmark of the project began at Tianwan-3 (China) three days ahead of the schedule.
During the tests, primary circuit pipelines and systems are pre-washed to remove debris left over after the installation is complete, said a press release.
As mentioned by ASE Project Manager in China Alexei Bannik, this operation signals the end of core installation works in the reactor unit and is a key to the preparation for hydrostatic tests and primary circuit flushing scheduled for this December.
Earlier this year, internals were installed into the reactor of Tianwan Unit 3. Installation of the reactor internals is considered to be an important stage of the reactor construction as they serve as a support for the core and secure nuclear fuel assemblies and control rod channels in place.
The internals also function as a coolant guide in the core and protection against neutron and gamma radiation.
The Tianwan nuclear station was built to the Russian AES-91 design and is the world`s safest nuclear power plant to date. The station operates two 1,000 MW reactor units launched in 2007.
Units 3 and 4, each with a 1,000 MW reactor, are currently under construction and scheduled for commissioning in 2018.
In October 2013, Rosatom`s fuel division TVEL signed a $1.0bn contract with Chinese companies to supply nuclear fuel and components for the new units at Tianwan. From the very beginning, they will run on TVS-2M, the latest and most advanced fuel developed by TVEL.
TVS-2M fuel has better performance characteristics and is more cost efficient as it enables longer refueling cycles. In late summer, TVS-2M fuel fabrication facilities at the Novosibirsk Chemical Concentrates Plant were visited by a delegation from the Tianwan project customer, Jiangsu Nuclear Power Corporation (JNPC).
JNPC representatives were demonstrated the manufacturing and testing of the first TVS-2M assembly for Tianwan-3. Following the visit, JNPC signed off the production of TVS-2M assemblies and components for the Tianwan nuclear station in accordance with the contract.
It should be noted that Russia is engaged in negotiations with China over the prospects of constructing units 7 and 8. Maintenance contracts signed between Rosatom and Tianwan over the last 3 years are worth more than US $ 50 million .