A research team led by Dr. In-Deok Park at the Korea Institute of Machinery and Materials (KIMM), has unveiled a groundbreaking underwater laser-cutting technique aimed at enhancing the safety and precision of nuclear reactor dismantling. This technique enables precise underwater cutting of the thick steel found in nuclear pressure vessels, effectively reducing the risk of contamination.
“The underwater laser cutting technology developed is significant as it directly simulates the nuclear dismantlement environment, greatly minimizing secondary contamination during the dismantling process,” stated Park.
With an increasing number of nuclear facilities scheduled for shutdown by 2050, KIMM’s laser technology addresses an urgent need. Even at simulated depths of up to 10 meters, the laser can cut through stainless steel thicker than 100mm, offering a robust solution for underwater conditions. This cutting-edge approach utilizes thermal cutting, a process that offers greater safety than conventional mechanical techniques by reducing risks associated with underwater work.
A critical feature of KIMM’s development is a specially designed tank that simulates underwater conditions up to 30 meters deep. Dubbed the “world’s first” of its kind, this patented tank enables researchers to test and refine their laser-cutting technology under realistic conditions. Additionally, the team designed a compact nozzle system optimized for high-pressure underwater operations and equipped with an anti-collision mechanism to prevent accidental damage to reactor structures.
“The team optimized the kerf width (cutting gap) to approximately 2mm and reduced the flow rate of cutting gas to 600?/min,” researchers explained, achieving a cutting speed of up to 50mm/min.
As more nuclear plants approach decommissioning, techniques like KIMM’s laser cutting are essential for safe and efficient dismantling. According to an International Atomic Energy Agency report, around 200 of the world’s 420 nuclear reactors will begin the decommissioning process by 2050. KIMM’s technology offers a promising solution for the controlled dismantling of reactors, ensuring safety for both workers and the environment.