Petrozavodskmash, AEM-Technologies, JSC Branch in Petrozavodsk (a member of Atomenergomash, machine engineering division of Rosatom Corporation, and Karelian Regional Branch of the Russian Engineering Union) executed assembly of primary circuit steam header bodies, designed to complete steam generators of Tianwan NPS, Power Unit 8.
Header body consists of several blanks, on internal surface of which anticorrosive layer is welded on. Then the parts of body are joined by automatic welding. After heat treatment, assembled item is to be finally machined. Necessary types of quality inspections are carried out during each manufacturing stage.
Content of delivery for one Power Unit is 8 header bodies - two per each of four steam generators. Petrozavodskmash has assembled all of the 8 items for Tianwan NPS, Unit No. 8. More than half of them have passed final machining and now they are being prepared for shipment.
Header body is a component of steam generator. It relates to the first safety class equipment and is a thick-walled cylinder of variable diameters and thickness. Total height of the item is more than 5 meters, maximum diameter exceeds 1 meter. Heat exchange goes between the primary and secondary circuit of reactor facility and heat is carried away from the reactor core through the header.
Tianwan NPS is located in Jiangsu Province, PRC. The first power units No. 1 and No. 2 with VVER-1000 reactors were accepted by the customer and put into warranty period operation in 2007. Units No. 3 and No. 4 were put into warranty period operation in 2018. In the same year, the intergovernmental protocol and framework contract for the construction of power units No. 7 and No. 8 of Tianwan NPS with VVER-1200 reactors relating to the latest generation “3+” were signed.