Preventive maintenance device and preventive maintenance method for piping inner surface

摘要

A preventive maintenance apparatus has a movable body (2) and a water jet peening (WJP) apparatus (3). The movable body installs a jet nozzle for driving and floating bodies (25) on a base body (62). The movable body suspended in cooling water in a reactor pressure vessel jets high-pressure water from a high-pressure pump from the jet nozzle, advances in the cooling water, and is inserted into a pipe (67) with the cooling water filled which is connected to the reactor pressure vessel. The posture of the movable body in the pipe is controlled by buoyancy adjustment of the floating bodies and the movable body can easily pass through a curve pipe portion (69). The high-pressure water from a high-pressure pump is jetted from jet nozzles of the WJP apparatus and for the inner surface of a vertical pipe portion, the WJP is executed.