Five units of equipment for two NPPs under construction in China with Rosatom’s assistance have been shipped from the production site of the Izhora plant in St Petersburg (part of Rosatom’s mechanical engineering division). Delivery of large-scale equipment weighing some 500 tonnes will be carried out by rail, road and sea.
The equipment comprises a pressure compensator for unit 8 of the the Tianwan NPP and four hydraulic tanks of the emergency core cooling system of unit 3 at the Xudabao NPP. A bubbler for Xudabao unit 4 was shipped from the ZiO-Podolsk plant near Moscow (also Rosatom’s mechanical engineering division).
At each stage of technological operations, the equipment underwent appropriate testing procedures in order to confirm compliance with quality requirements for nuclear energy facilities. All tests were carried out with the participation of Chinese specialists.
A pressure compensator is an important component of the reactor hall equipment. It is designed to provide the required pressure in the primary circuit of the reactor. When assembled, its length is about 14 metres with a diameter of 3.3 metres and weighs 186 tonnes.
The hydraulic tanks for the emergency reactor core cooling system are a key element of the NPP safety system. Four independent tanks weighing 75 tonnes with a volume of 60 cubic metres are filled with an aqueous solution of boric acid and are connected by a pipeline to the reactor vessel.
The bubbler is designed to condense steam coming from the pressure compensator and other primary circuit equipment in heating modes and other operating modes of the reactor. The device is made of austenitic chromium-nickel steel. The 15-tonne component is about 8 metres long, 4 metres high with a diameter of 2.5 metres.
Previously, the Izhora plant manufactured and sent to China pressure compensators for Tianwan 7 and Xudabao 3 as well as a set of hydraulic tanks for the emergency core cooling system of Tianwan 7. Bubblers produced by ZiO-Podolsk are currently operating at the Kudankulam NPP in India as well as Russia’s Rostov and Leningrad NPPs.
Tianwan 1&2 with VVER-1000 reactors were handed over to the customer and put into warranty operation in 2007. Units 3&4 were put into warranty operation in 2018. The same year, an intergovernmental protocol and a framework contract was signed with Rosatom for the construction of Tianwan 7&8 and Xudabao 3&4 with VVER-1200 reactors.