| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for improving residual stresses in an inner surface of a pipe, in which the residual tensile stresses in the axial direction of the inner surface of the pipe at a part to be improved, can be improved, and a pipe improved in residual stresses in inner surface thereof. SOLUTION: Stress improvement heat input areas L5-L7 are set by deviating the position in the axial direction of a pipe 20 with respect to the part O to be improved where the residual tensile stress in the inner surface of the pipe 20 must be improved. The welding heat input higher than those in areas L1-L4 including the part O for improvement is given to an outer surface of the pipe at the set stress improvement heat input areas L5-L7. COPYRIGHT: (C)2009,JPO&INPIT |
