Manipulator for opening and for closing a swinging cover for a manhole of a steam generator and associated opening and closing methods

A manipulator for opening and closing a swinging cover for a manhole of a steam generator, the manipulator comprising:

• a hand trolley assembly;
• and
• a winch assembly engageable with the swing cover and detachably mounted to the hand trolley assembly, the winch assembly including a winch provided with a pair of wires, a pair of hooks configured to hang the winch assembly on an axle of the swinging cover and two threaded anchors, each threaded anchor being attached to an end of one of the wires and being configured to pass through a first through hole of the swinging cover and to be threaded into a second threaded hole provided on a base plate of the steam generator so as to provide a support point for the associated wire, the winch being adapted to wind and alternatively unwind the two wires so as to rotate the swinging cover between a closed cover position in which the first through hole is aligned with the second hole and an open cover position in which the swinging cover is at a neutral hanging point.