Design and Test for a High-Temperature Molten Salt Pump

A high-temperature molten salt pump, described as mechanical, free-surface, centrifugal, vertical-shaft, sump type, working at 500°C [932°F] to 600°C [1112°F], has been developed for the Thorium-Based Molten Salt Reactor (TMSR). Flow passage components of the pump are made of Hastelloy C-276 to ensure sufficient strength and corrosion resistance at high temperature. Also, a heat shield plug with air-cooled channels was designed to separate the drive motor, seal elements, and bearings from intense radioactivity and to keep the temperature of the flange seal below 150°C [302°F] and the temperature of the bearing below 80°C [176°F]. A dry gas seal was used so that there is zero leakage. Furthermore, some analysis of hydraulics characteristics, temperature field, thermal stress, and strain was performed to research the pump’s performance, and then the temperature field and the hydraulics were measured to validate the analysis results. The results show that the hydraulics, thermal stress, and strain meet the design value very well. The pump has been successfully operated on a LiF-NaF-KF test loop for over 250 hr. at temperatures of 500°C [932°F] to 600°C [1112°F], speeds of 1050 to 1450rpm, and flows of 15 m3/h [66 gpm] to 25 m3/h [110 gpm]. Paper published with permission.