Jiangsu Haifa Machinery Manufacturing Co., Ltd.

At the Cold Source Safety Forum of the Shenzhen Nuclear Expo, Zhang Zhenglou, Deputy Chief Engineer of the Civil and Utility Facilities Division at Shanghai Nuclear Engineering Research and Design Institute Co., Ltd., delivered a keynote report titled Research on Failure Indicators and Equipment Technology Directions for Cold Source Prevention and Control. The report focused on risk control of nuclear power plant cold source systems under large-scale marine organism intrusion scenarios, with an in-depth analysis of the formation mechanisms of issues such as drum screen clogging, circulating pump trip, and interception net failure, while also exploring future directions for equipment technology. In the report, the research team compared the prevention and control effects under variable-frequency operation of circulating pumps versus pump shutdown conditions. The results showed that when the flow rate of a single circulating pump was reduced to 50%, the system's maximum clogging rate and instantaneous load-bearing capacity improved only marginally. The tolerable marine organism density increased from approximately 10.5 g/m³ to22.6 g/m³—an improvement, yet still insufficient to meet the demands of extreme marine organism intrusion scenarios. In contrast, when all circulating pumps were shut down and only the essential service water pumps were kept running, the system's capacity to withstand marine organism density rose to approximately 400 g/m³, representing a tenfold or even several dozen-fold increase over normal operating conditions. This indicates that under extreme marine organism outbreak conditions, shutting down circulating pumps and prioritizing the operation of the essential service water system has a more significant effect on reducing the risk of drum screen clogging. However, the report also noted that while the front-end cold source risk is alleviated, the load-bearing capacity of downstream small-scale traps and filters remains a critical weak link in the system. Future development of nuclear power cold source safety technologies requires further strengthening of research and application in high-capacity filtration equipment, large-flow circulation systems, and intelligent early warning technologies, thereby comprehensively enhancing the safety and reliability of nuclear power plant cold source systems in complex marine environments. Jiangsu Haifa Machinery Manufacturing Co., Ltd. was restructured from Jiangsu Ligong Group Co., Ltd.'s Jingjiang Stainless Steel Pump and Valve Factory, which was originally established in 1958 under the Steel Research Institute of the Ministry of Metallurgical Industry. The company primarily manufactures API610 chemical process pumps—OH1, OH2, OH3, OH4 pumps; BB1 to BB5 multi-stage pumps; VS1 to VS6 barrel-type pumps; HES-type chemical process pumps; sixth-generation ultra-low carbon stainless steel high-quality leak-proof molten urea pumps; urea hydrolyzer feed pumps; high-temperature asphalt pumps; pitot tube pumps; rotary jet pumps; molten salt pumps; vertical submerged pumps; high-temperature nitric acid magnetic drive pumps; magnetic drive pumps for conveying solid-containing media; industrial pumps; canned motor pumps; slurry pumps; titanium tetrachloride pumps; strong self-priming pumps; lined fluorine pumps; leak-proof pumps; alkali pumps; axial flow pumps; long-shaft vertical submerged pumps; CQC first-level energy-efficiency chemical pumps; and high-pressure descaling industrial pumps. Website: www.jslgpump.com Contact: 13905263417 E-mail: jslgpump@gmail.com E-mail: jsareva@163.com