On March 12, using the metal forming technology developed by the Institute of Metal Research of the Chinese Academy of Sciences, the world's largest welded integral stainless steel ring forging was successfully rolled. The ring has a diameter of 15.6 meters and a weight of 150 tons. It has achieved the 100-ton class metal billet grading and forming for the first time. This is also the world's largest forged stainless steel ring with the largest diameter and weight. The giant ring will be used in China's fourth-generation nuclear power units, and its successful development will effectively guarantee the implementation of major equipment in China's nuclear industry.
As the support ring of the core components of the fourth-generation nuclear power unit in China, not only the pressure vessel boundary and safety barrier, but also the weight of 7,000 tons in structure, it is the "backbone" of the entire reactor. In the past, such giant forgings were manufactured by multi-section billet welding in foreign countries, which not only had long processing cycles and high costs, but also had weak structural properties of the material at the weld location, which posed a hidden safety hazard to the operation of nuclear power plants.
Under the entrustment and support of China National Nuclear Corporation, the Institute of Metals, Chinese Academy of Sciences set up an industry-academia-research team, applying TISCO's high-purity continuous casting slabs and developing a ring-shaped forging with a diameter of 15.6 meters in SDYL Heavy Industry Technology. High degree of organization and good uniformity.
The researchers from the Institute of Metal Research of the Chinese Academy of Sciences introduced that the original metal construction forming technology broke through the limitation of the idea of "big system and big system" for large forgings. Surface activation, vacuum encapsulation, multi-directional forging, graded construction, integral rolling ring and other key technologies have been completely eliminated. The interface between multiple layers of metal is made, so that the position of the interface of the supporting ring forging is completely consistent with the composition, structure, and performance of the base metal. A new type of manufacturing that "makes small by big" has been realized, which has greatly improved quality and reduced manufacturing costs. .
This technology has been evaluated by many academicians and experts as a transformative innovation in the field of large component manufacturing, and has been applied in the fields of hydropower, wind power, nuclear power and other fields. It has promoted the rapid development of high-end equipment in China and guaranteed the independent and controllable play of core materials of major equipment Played an important role.