The installation of the upper part came a month after the lower tier was lifted into position. The plant uses a double containment to maximise safety, with reinforced concrete protecting the plant from external hazards including natural disasters such as earthquakes.
The Tianwan plant is being built by Russia's Rosatom - in June 2018, Russia and China signed four agreements, including for the construction of two VVER-1200 reactors as units 7 and 8 of the Tianwan plant. They are scheduled to be commissioned in 2026-2027.
The latest landmark moment came two years after China's President Xi Jinping and Russia's President Vladimir Putin took part in a virtual ceremony to mark first concrete on the unit.
Alexei Bannik, vice president for projects in China and advanced projects of Atomstroyexport JSC, said: "The construction of the seventh unit at the Tianwan NPP is being carried out right on time. The next stage will be the installation of key equipment inside the reactor building - the reactor pressure vessel, steam generators, hydraulic tanks of the emergency core cooling system, pressure compensator, main circulation pumps."