Abstract: A polishing apparatus is provided with a machining head that is supported to freely move in two horizontal directions; driving devices that enables the machining head to move; a polishing jig that is supported by the machining head to freely move in a vertical direction; a polishing member that is mounted on a lower end portion of the polishing jig; an air cylinder polishing jig moving device that moves the polishing jig and is capable of pressing the polishing member against a tube support plate; and a drive motor that is capable of rotating the polishing jig, thus, simplification of the structure is made possible.

Abstract: A cleaning device of a porous plate for nuclear power including: cleaning tanks (72, 73) that is capable of storing a cleaning liquid therein and is capable of housing the porous plate (43) in an upright state; a rotation device (84) that is capable of rotating the porous plate (43) within the respective cleaning tanks (72, 73); and an ultrasonic wave oscillation device (111) that irradiates the porous plate (43) within the cleaning tanks (72, 73) with ultrasonic wave. Thus, it is possible to efficiently remove the adhered foreign substances.

Abstract: A polishing apparatus is provided with a machining head that is supported to freely move in two horizontal directions; driving devices that enables the machining head to move; a polishing jig that is supported by the machining head to freely move in a vertical direction; a polishing member that is mounted on a lower end portion of the polishing jig; an air cylinder polishing jig moving device that moves the polishing jig and is capable of pressing the polishing member against a tube support plate; and a drive motor that is capable of rotating the polishing jig, thus, simplification of the structure is made possible.

Abstract: A cleaning device of a porous plate for nuclear power including: cleaning tanks (72, 73) that is capable of storing a cleaning liquid therein and is capable of housing the porous plate (43) in an upright state; a rotation device (84) that is capable of rotating the porous plate (43) within the respective cleaning tanks (72, 73); and an ultrasonic wave oscillation device (111) that irradiates the porous plate (43) within the cleaning tanks (72, 73) with ultrasonic wave. Thus, it is possible to efficiently remove the adhered foreign substances.

Abstract: A tube expansion method of fixing a heat exchanger tube inserted to a tube hole of a tubesheet by tube expansion including: when there is a groove along a circumferential direction with respect to an inner circumferential surface in the middle axis of an axis direction of the tube hole, a first hydraulic tube expansion step of performing hydraulic tube expansion at a pressure of 15% and 70% in a range including the groove, and thereafter, a second hydraulic tube expansion step of performing each liquid tube expansion at a pressure of 100% in each range divided except the groove.