| 摘要 |
A method for replacing a steam generator of a pressurized water reactor of a 2-loop type of the present invention comprises: a pre-replacement step 1 which includes acquisition of various data from a stop condition of the steam generator at room temperature; a pre-replacement step 2 which includes motion monitoring during a run by attaching a displacement sensor, a temperature sensor, etc. to the steam generator; a step of steam generator pipe cutting and snubber disassembling, which includes elimination of a remaining weight by fully allowing motion while cutting pipes of the steam generator, and cutting in free condition of fully excluding any restriction power; a decontamination step which removes radioactivity from high temperature pipes and intermediate pipes; a step of installing multiple hydraulic devices on a forged anchor plate; a step of installing a sliding base on the hydraulic device; a step of mounting a shim plate on the sliding base; a step of setting and aligning the steam generator on the shim plate; a step of aligning a fine gap using the hydraulic device; an installing step, while welding and connecting pipes of the steam generator, monitoring displacement that occurs during welding and connecting, and compensating for the displacement using a displacement sensor and the hydraulic device in real time; and a step of mounting insulating materials at the bottom of the steam generator. According to the present invention, by combining and applying the procedures for installation or replacement of the steam generator of a nuclear power plant under construction and an operating nuclear power plant, no remaining stress exists at the nuclear reactor facility. As there exists no remaining stress of any kind at the nuclear reactor coolant system and structural vibration of the nuclear reactor is minimized, the wearing of the steam generator′s fine pipes and a nuclear reactor coolant system facility can be prevented. |
