en.Wedoany.com Report, At 00:58 on March 29, following the completion of 24-hour data collection after the pressure inside the steel containment vessel steadily dropped to atmospheric pressure, the Containment Structural Integrity Test (SIT) and Integrated Leakage Rate Test (ILRT) for Unit 3 of China National Chemical Engineering Sanmen Nuclear Power Plant in Zhejiang were successfully completed, with all test results meeting the required standards.
The containment vessel is the third critical barrier in a nuclear power plant to prevent the release of radioactive materials. Its structural strength and sealing integrity are directly related to the operational safety of the plant. Conducting SIT and ILRT tests before the commissioning of a new unit is a core step in verifying the reliability of this barrier. These tests involve injecting compressed air into the steel containment vessel to simulate pressure conditions under design-basis accidents, comprehensively examining the structural integrity and overall sealing performance of the containment pressure boundary.
To ensure the success of the tests in a single attempt, Sanmen Nuclear Power established a specialized test command center in collaboration with the commissioning team, Shanghai Nuclear Engineering Research & Design Institute, State Nuclear Power Equipment, State Nuclear Power Operation, China Nuclear Industry Fifth Construction Co., Ltd., China Nuclear Industry 22nd Construction Co., Ltd., and other participating units. The command center led the team in preparatory work, developing specific test plans and safety protocols, identifying test prerequisites, and implementing them one by one. Once the tests began, the command center operated on 24-hour shifts, monitoring progress in real-time, coordinating on-site issue resolution, and ensuring the orderly advancement of all work stages. All personnel involved remained at their posts, worked collaboratively, strictly followed test procedures, closely monitored test data, precisely controlled pressure increase and decrease rates, and successfully completed critical tasks such as weld and penetration inspections, ensuring the safety and controllability of the test process and the accuracy and authenticity of the data.
The successful completion of these tests fully validates the manufacturing and installation quality of the containment vessel, laying a solid foundation for similar tests and hot functional tests of subsequent units.
