METHOD FOR DISMANTLING HEAT EXCHANGER INSTALLED IN BUILDING FOR NUCLEAR REACTOR

In a method for dismantling a heat exchanger installed in a nuclear reactor building, a contamination controlled area is minimized. The method includes: an introducing step of introducing a part of a heat exchanger (100) in a contamination controlled area, the introducing step including providing the contamination controlled area in a part of the nuclear reactor building, suspending the heat exchanger by a jack down unit provided in the nuclear reactor building, and lowering the heat exchanger; a first cutting step of cutting the part of the suspended heat exchanger by a first cutting unit (300) provided in a first cutting area in the contamination controlled area to thereby separate a sectioned cut-piece from the suspended heat exchanger; a conveying step of conveying the sectioned cut-piece from the first cutting area to a second cutting area in the contamination controlled area by a conveying unit (500) ; a second cutting step of cutting the conveyed sectioned cut-piece into small pieces by a second cutting unit (400) provided in the second cutting area; and a carrying-out step of carrying the sectioned cut-piece cut into the small pieces out of the contamination controlled area with the sectioned cut-piece packed in a container.