Among the nuclear power plant facility improvement projects, out of a total 10 replacement reactor vessel closure head (RRVCH), five have been replaced, starting with Gori Unit 1, and five, including Hanul Unit 1, Hanbit Units 5 and 6, and Hanul Units 3 and 4 will be replaced in the future. This paper presents the method of treating Latch Housing among radioactive waste generated during the replacement of Hanul Unit 2 (February 2023). Latch Housing controls the control rod by receiving magnetic force from the CRDM’s Coil Stack. Located in the Old Reactor Vessel Head (ORVH) Hot Spot, the range of measured radiation dose rate was 0.3 to 0.8 mSv h-1 (up to 4.5 mSv h-1). The amount of radioactive waste generated was 35.8 Baler-Drum (based on 200L), and the order of treatment was to cut into the Omega Seal of the CRDM, the CRDM and Latch Housing Transfer, the boundary of the CRDM and Latch Housing, the Rod Travel Housing, the Motor Housing and the Latch Assembly, and then transfer and Drumming. In the United States, out of 93 operating reactors, 31 reactor vessel heads have been replaced and 19 reactor vessel heads are scheduled to be replaced. In Korea, 25 reactors are in operation, and two reactors have been permanently shut down. Among them, the nine old reactors for more than 30 years (as of September 2021) are expected to achieve ALARA and reduce radwaste management costs through the management method applied to replace the reactor vessel head.

In this study, simulation studies were conducted to develop insert injection molds to improve the mass production of terminal assemblies. For the main part of the automobile door latch, charging, holding pressure and deformation analysis were performed according to the gate position of the injection process. As a result of injection molding analysis of the terminal assembly, the flow pattern was uniformly made while maintaining a constant balance of the filling of the product, and the pressure distribution at the time of filling was confirmed. When the analysis results are applied to the mold fabrication in the improved structural method, the transfer lines of the molten resin are controlled by the dam of the 1st injection molding, so that the transmission line is not short-circuited or deformed, and the watertightness, corrosion resistance, and good surface We believe the injection will be possible.