Abstract: To ensure the sealed fixing of a replacement heating rod (4) on a collar (3) for passing through the casing (1) of a pressurizer, a weld is made in a single pass by a regulated MIG process. A shaft is fixed on one end of the heating rod projecting in relation to the collar (3) and in the extension thereof. A welding device is engaged and fixed in position on the shaft, this welding device comprising a tubular support (14) and an inert-gas orbital welding torch (10) with an electrode made of fusible metal, rotatably mounted about the axis of the support (14) which coincides with the axis of the rod (4). The welding torch (10) and a device to unwind welding wire which is placed in a cabinet (6) are set into synchronous rotation during the welding, by appropriate drive means. The welding is carried out in a single pass on the entire periphery of the heating rod (4) and of the collar (3).

Abstract: The tubular wall (1) of the irradiated component is machined on its upper annular surface, with chips (44) being formed by the use of a metal working machine (30) bearing on this upper surface and moving in rotation about the axis (6) of the wall (1) of the component. The chips (44) formed by the metal working machine (30), e.g., a milling head, which moves in the vertical direction and downwards, are collected and cleared away continuously during the progress of the machining in the axial direction (6) of the wall (1) of the component. The device is fastened to the upper part of the tubular casing (1), arms (7a, 7b) equipped with jacks allowing the device (4) to be flanged to the wall (1) of the component, and bearing devices (12) comprising arms (13) being mounted pivotably about a horizontal axis between a low bearing position and a high withdrawal position (13'). The bearing arms (13) change from their low position to their high position at the moment when the machining tool (31) passes.

Abstract: To ensure the sealed fixing of a replacement heating rod (4) on a collar (3) for passing through the casing (1) of a pressurizer, a weld is made in a single pass by a regulated MIG process. A shaft is fixed on one end of the heating rod projecting in relation to the collar (3) and in the extension thereof. A welding device is engaged and fixed in position on the shaft, this welding device comprising a tubular support (14) and an inert-gas orbital welding torch (10) with an electrode made of fusible metal, rotatably mounted about the axis of the support (14) which coincides with the axis of the rod (4). The welding torch (10) and a device to unwind welding wire which is placed in a cabinet (6) are set into synchronous rotation during the welding, by appropriate drive means. The welding is carried out in a single pass on the entire periphery of the heating rod (4) and of the collar (3).

Abstract: The apparatus comprises a storage container (11) for the elongate flexible element (97), guide pulleys (12, 13, 14) and an assembly (15) movable in either direction around the components to be welded (2). One of the guide means (12, 13, 14) is motorized. The annular assembly (15) comprises carriages (43) moving on the rail of the welding head (6) and connected to a master carriage whose movements are subject to the movements of the welding head (6), and an annular trough which receives the flexible element (97) and which is fastened to the movable annular assembly (15).