The utility model discloses a U type rings structure, U type rings are pre -buried in prefabricated component, U type rings are U shaped steel stranded conductor, U type rings tip in the prefabricated component is equipped with the extrusion sleeve, be equipped with the steel anchor slab between extrusion sleeve and the U type rings, U type rings embedding some position department surperficial at prefabricated component is equipped with circular groove, the outside cover of U type rings that exposes outside prefabricated component has the sleeve pipe, provide U type rings structure, high tensile strength, the ordinary reinforcing bar of fungible uses as rings, the realization is lifted by crane heavier prefabricated component's safety, the upset, work such as installation, moreover, the steam generator is simple in structure, in the time of save material, furthermore, the visual switch has good economical efficiency, the storing pallet rack is highly practical.