The Volgodonsk branch of AEM-Technologies, Atommash (part of Rosatom’s mechanical engineering division Atomenergomash) has manufactured the upper half of the reactor pressure vessel (RPV) for unit 3 of China’s Xudabao NPP in Liaoning Province, Atomenergomash said on 20 April. Atommash has completed the welding of circumferential seams on upper half of the RPV. The work lasted 25 days with continuous heating at 150-170 degrees Celsius in the area of welded joints. It took 4,700 kg of flux and 3,300 kg of wire to weld the circumferential seams. The component was then heated to 300 degrees and moved to a furnace for heat treatment to obtain the required mechanical properties of the metal. The process of heating and holding is done at a maximum temperature of 620 degrees for three days.

Control checks are then undertaken including visual-measuring, ultrasonic tests, magnetic particle flaw detection, and x-ray gammagraphy of the welded joints. Corrosion-resistant surfacing on the inside of the semi-hull will follow. For Xudabao units 3 and 4, two RPVs with internals, a cover and an upper unit and two sets of steam generators are being manufactured. The design and construction of the facility is being carried out by the Rosatom’s Engineering Division with commissioning of the units scheduled for 2027 and 2028.


Image: The upper reactor semi-vessel for Xudapu 3 (Photo credit: AEM Technologies)