| 摘要 |
PURPOSE:To manufacture a polygonal Zr alloy pipe having superior corrosion and deformation resistances and maintaining the size and shape correctly by subjecting a polygonal pipe to beta-hardening and carrying out annealing while cramping and supporting the pipe from the inside or outside with a jig. CONSTITUTION:During the manufacture of a polygonal Zr alloy pipe used in a nuclear reactor, a pipe 3 to be heat-treated is hardened by heating to a temp. at which at least part of the alpha-phase is transformed into beta-phase and quenching to enhance the corrosion resistance, and it is annealed at 550-650 deg.C to relieve various strains and to enhance the deformation resistance. During the annealing, by cramping the pipe 3 with a jig, the size and shape of the pipe are regulated. The jig is an external cramping type jig composed of an outer spacer 5 having a higher coefft. of thermal expansion than the pipe 3 and an inner spacer 4 having a higher coefft. of thermal expansion than the spacer 5 or an internal cramping type core jig 8 having a higher coefft. of thermal expansion than the pipe 3. |
