Abstract: Sleeves inserted in the coolant conductors of a steam generator of a nuclear-reactor plant are rolled by remotely controlled apparatus minimizing the time which personnel must spend within the radioactive environment of the channel head of the steam generator. A sleeve is rolled by a tube provided with rolls which are normally retracted and which, during a rolling operation, are extended into rolling engagement with the sleeve by a rotating tapered mandrel. The mandrel advances into the tube rotating the rolls while progressively increasing the pressure between the rolls and the sleeve. The sleeve is rolled near its upper end and also at its lower end in its region which is within the tube sheet by upper and lower rolling tools. The tube carrying the rolls is moved into the sleeve by a remotely controlled drive. The drive is a low voltage motor for the upper tool and a hydraulically driven piston for the lower tool.

Abstract: The hollow tubular member or blank which is to serve as a sleeve for a corroded tube of the steam generator of a nuclear reactor plant and which is too long to be manipulated under the tube sheet of the reactor, is prebent into a shape such that it can be manipulated and is then progressively straightened under the tube sheet as it is progressively inserted into the tube. The straightener includes a plurality of grooved rolls mounted staggered and rotatable in a train. Each roll forms a channel engaging half of the periphery of the member. The contour of the engaging surface of each roll is the same as the contour of the member over half of its peripheral surface so that each roll mates with the member over half of its peripheral surface.

Abstract: The expansion of the primary tubes or sleeves of the steam generator of a nuclear reactor plant are measured while the tubes or sleeves are being expanded. A primary tube or sleeve is expanded by high pressure of water which flows through a channel in an expander body. The water is supplied through an elongated conductor and is introduced through a connector on the shank connected to the conductor at its outer end. A wire extends through the mandrel and through the conductor to the end of the connector. At its inner end the wire is connected to a tapered pin which is subject to counteracting forces produced by the pressure of the water. The force on the side where the wire is connected to the conductor is smaller than on the opposite side. The tapered pin is moved in the direction of the higher force and extrudes the wire outwardly of the conductor.