Study On Steam Generator Channel Head Nozzle Dam

Steam Generator channel head nozzle dam is a kind of special maintenance tool used in nuclear power station refueling outage.The inlet and outlet nozzle dams are employed only during outage operations.They provide leak proof seal between the interior of the steam generator channel head and the refueling pool.Thus,maintenance of the steam generators and refueling work can be performed simultaneously.The purpose of this paper is to research and development the SG nozzle dam which can meet the function requirement of three generation passive nuclear power station.We summarize the function requirements of SG nozzle dams by investigation and study.SG nozzle dam is mainly composed of support sheet and air cell.The pressure-bearing function is realized by support sheet and the sealing function is realized by the air cell.This paper completes the design of support sheet through the material selection and 3D modeling.We choose the best scheme by comparing finite element analysis stress and deformation results of several different structures.The quality of equipment is reduced on the basis of ensuring the bearing capacity.We complete the design of multi sealing combined air cell through material selection and structure optimization.And the performance of air cell is improved by process design.After the design and fabrication of SG nozzle dam,we complete a series of test to ensure the function and reliability.We develop a kind of SG nozzle dam that combining economical efficiency,maintenance convenience and reliability.This SG nozzle dams can be directly applied to China's third generation nuclear power plants.And the data in this paper can provide reference for design and application of SG nozzle dam in other nuclear power plants.