The application provides a fuel rod bundle automatic assembling device, which comprises a truss, a feeding mechanism, a pre-positioning mechanism, an assembling mechanism and a
workbench, the pre-positioning mechanism is arranged on the
workbench, and a vertical grid plate and a rod box for containing fuel rods are further fixed on the
workbench, the rod box, the pre-positioning mechanism and the grid plate are arranged side by side, the feeding mechanism is movably connected to the truss and is used for moving the fuel rods in the rod box to the pre-positioning mechanism, the pre-positioning mechanism is arranged on the workbench and is used for axially and circumferentially positioning the fuel rods, so that the through slot on the end plug of the fuel rod is vertically arranged and corresponds to the
insertion part of the grid plate on the workbench, and the assembling mechanism is movably connected to the truss and is used for moving the fuel rods positioned on the pre-positioning mechanism to the grid plate, so that the fuel rods and the grid plate are inserted through the through slot and the
insertion part. The application can realize the
automation and intelligentization of the rod bundle assembling process, so as to improve the automatic assembling efficiency of the rod bundle.