The primary loop confinement and pressure boundary system of the HTR-10

Abstract

The design philosophy and requirements of the HTR-10 reactor building and the primary loop confinement are introduced in this paper. Also introduced are the design, fabrication and the installation of the HTR-10 primary loop pressure boundary system. The primary loop confinement comprises the sealed cavities of the reinforced concrete structure. The main components and the connected gas systems of the primary loop pressure boundary system are contained in the confinement. Under normal operating condition, the inside pressure of the confinement is kept at negative pressure to ensure the sealing function of the confinement. There is a rupture disk of overpressure protection in the confinement wall. After a depressurization accident the pressure of the confinement increases and the rupture disk will break. The air of the confinement is discharged directly to the atmosphere through the accident discharge chimney which is connected to the rupture disk without filter. The main components of the primary loop pressure boundary system consist of the reactor pressure vessel, the steam generator pressure vessel and the hot gas duct vessel. All the above main components are installed in the reactor cavity and the steam generator cavity. They are all nuclear safety class 1 components, whose materials production, design, fabrication, and tests are carried out according to ASME Section III and relevant Chinese nuclear codes.