Abstract: A water-chamber working apparatus (1) that performs a predetermined work inside a water chamber (131) of a steam generator (130) including a support shaft (2) that is formed to be extendable and retractable, a rotary means (3) that is respectively provided at opposite ends of the support shaft (2) rotatably around a vertical shaft center, while coming into contact with an inner wall surface (131a) of the water chamber (131) by extension of the support shaft (2), and a movable body (4) that is provided to be movable along the support shaft (2).

Abstract: A water-chamber working apparatus (1) that performs a predetermined work inside a water chamber (131) of a steam generator includes at least two locking units (2) inserted into and locked to heat transfer tubes (132) provided on a tube plate (137) in the water chamber (131), a support means (3) spanned between the respective locking units (2), and a movable body (4) movably provided along the spanned support means (3). Accordingly, the movable body (4) can be stably supported in the water chamber (131) and can be easily moved.