Abstract: The apparatus carried by a suitable handling device, and comprising a first base structure attached to the handling device and provided with vertical guides for the sliding of a first carriage, a second base structure attached to said carriage and provided with horizontal guides for the sliding of a second carriage, and an operating head carried by the second carriage through a hydropneumatic device comprising at least one double-acting penumatic cylinder for supporting said head and having its axis vertically arranged, and a hydraulic damper connected between said second carriage and operating head, the lower chamber of the operating head supporting pneumatic cylinder being supplied with a first value of pressure as to cause a fast lifting of said head, while the upper chamber of the pneumatic cylinder is supplied with a value of pressure at a lower level as to annul the upward thrust, at the same time supplying said operating head with a downward operative thrust of a constant value.

Abstract: The invention relates to a grate for supporting tube plates for assembling in a steam generator or the like. The grate is characterized in that the ends of the plates forming the grating penetrate into and are received, at least partially, without any longitudinal gap or clearance in grooves in the frame body, which frame is preferably formed by three rings, at least partially superimposed, of which the intermediate ring has said grooves, while the other two upper and lower rings are secured to said intermediate ring and enclose therebetween the ends of the individual plates threaded in the grooves of the intermediate ring; a diametrical stiffening device secured by welding is also provided. It is the object of the invention to provide an economical and efficient grate allowing to avoid welding of the plates to one another and between said plates and frame, while ensuring the greatest reliability.

Abstract: Apparatus for controlling and taking up the axial displacement of large rotating cylinders, comprising a pair of end bearings, of which one is provided with driven rollers, while the other is provided with idle rollers, one of which is carried by a bearing orientable about a vertical axis. A first transducer senses the axial displacement of the cylinder and its output is connected to an input to a first device effecting a comparison with a reference signal; the output of the first comparing device is connected through an amplifier to an input to a second comparing device, a second input of which is connected to the output of a second transducer sensing the displacement of the guide roller bearing. The output of the second comparing device controls a servoactuator mechanically connected to the orientable bearing of the guide roller.

Abstract: A supporting grid for pipes comprising a frame and a reticular structure made of different materials having different thermal expansions, wherein a manhole and associated cover are provided, wherein said cover is made with the same material as the reticular structure and is secured to it, and wherein one or more connections are provided between said cover and said frame for preventing only tangential movements relative to the frame, while one or more connections are provided for preventing only movements perpendicular to the grid surface, enabling all these connections free thermal expansion of said reticular structure and said cover relative to said frame.

Abstract: The invention refers to a supporting grid for pipes particularly in steam generators, heat exchanger and other thermic apparatus.This supporting grid is formed of a plurality of intersecting strips forming a reticular structure joined to a peripheral frame, characterized by the fact that the connection between the strips and the peripheral frame is made by means of precision mechanical fixing joints, which prevents reciprocation of the parts but permits free thermic expansion of the same.

Abstract: A method of manufacturing a grill-type support suitable to act as a support and tube spacing member for steam generators (particularly natural circulation steam generators for pressure water reactors), heat exchangers and the like, wherein the actual lattice of the grid comprises strips having a certain thermal expansion, whereas the frame is made of another material having different thermal expansion, and during assembling the outer frame is connected to the strips, so as to be fast therewith and remains so for all the time required for manufacture, transport and erection, whereas as soon as said generator is set to work said strips of different material can slide relative to said frame, so that, said frame while surrounding and supporting such strips, allows a different thermal expansion for said central strips and frame.