TUBE EXPANSION METHOD

摘要

This tube expansion method, which causes a heat conduction tube (105) inserted in a tube hole (104a) of a tube plate (104) to be affixed by means of tube expansion, includes: a first hydraulic tube-expansion step wherein, when there is damage (104b) along the peripheral direction at the inner peripheral surface partway along the axis (S1) direction of the tube hole, hydraulic tube-expansion is performed of the range including the damage at 15-70% pressure; and next, a second hydraulic tube-expansion step wherein hydraulic tube-expansion is performed of each range split by excepting the damage at 100% pressure.