en.Wedoany.com Reported - The steel liner dome of the nuclear reactor building for Ningde Nuclear Power Unit 5, constructed by CGN Engineering, has been successfully lifted. The 271-ton "steel roof" was smoothly placed onto the 45-meter-high nuclear reactor building, with the alignment error controlled at the millimeter level. This lifting operation achieved zero safety incidents and full compliance with quality standards.
Ningde Nuclear Power Unit 5 adopts China's self-developed third-generation nuclear power technology, the "Hualong One." To ensure no centimeter-level collisions occur during the dome lifting, Li Gang, manager of the construction division of CGN Engineering's Ningde Project Department, required all risks to be eliminated on the ground. The project team introduced digital technology, collaborating with design and surveying professionals to conduct high-precision 3D scanning. They completed scanning and verification at 14 stations inside the dome and on top of the containment, constructing a 1:1 "digital twin" model in the computer. By simulating the process in a virtual space, the team accurately identified seven core risk points, confirmed the minimum safe clearances in key areas such as dome cables and the ring crane arch, and eliminated potential collision hazards in advance.
During the lifting process, Zhou Li, deputy general manager of the Ningde Project Department and chief lifting commander, coordinated multiple construction teams including hoisting, surveying, and civil engineering. When the dome rose to a height of 45 meters and approached the installation point, the operation entered a fine-tuning phase. Eighteen 32-ton jacks worked in coordination to perform millimeter-level precision adjustments of the dome's orientation. According to verification by professional surveyors, the deviation at the 0° direction of the dome was only 2 millimeters, and at the 180° direction, it was 3 millimeters, both better than the standard limit of 5 millimeters.
The foundation of large equipment lifting lies in stability. The 2,000-ton crawler crane was the core equipment. Ge Chunlei, the on-site technical director, required using the highest point of the site as a benchmark and leveling low-lying areas with fine sand. The project team conducted point-by-point high-density precision measurements of the crane's travel and positioning areas, eliminating uneven ground hazards through repeated measurements and fine adjustments. During the laying of road base boxes, the team adopted a synchronized approach of "laying, measuring, and adjusting simultaneously," controlling the ground slope of the crawler crane's working area to within 0.5%.
The project team established a Party member task force for the dome lifting and comprehensive excellence of Unit 5 of the Ningde Phase II project, implementing a dual management mechanism of "grid-based + checklist-based" control. The site was divided into multiple safety management grids, with a one-post-one-responsibility checklist developed, and all operations were fully documented. The team, together with the owner and construction units, formed a joint quality assurance supervision group, developed a joint supervision and assurance plan for dome assembly and lifting, identified key risks, and issued timely warnings and corrective actions. Zhou Li stated that before the formal lifting, the team also conducted a "full-process simulation drill with an empty hook" to ensure operators were proficient in emergency response procedures.
This lifting not only ensured the steady progress of the nuclear power unit but also accumulated a replicable set of safety control experience for "Hualong One" dome lifting.
