OUTILLAGE POUR L'ASSEMBLAGE DE DEUX PIECES ANNULAIRES DE CARTER

The tool comprises: units for supporting and positioning workpieces (1a, 1b) so that the units are present in contact with an annular zone to be welded; a friction welding head that is movable in rotation around an axis perpendicular to an axis (A) of the workpieces and comprises a body and a mixing pin; a unit for radial displacement of the welding head compared to the worpieces so as to penetrate the mixing pin on the annular zone or to withdraw the mixing pin from the zone; and a unit for rotating the workpieces relative to the welding head so as to move the mixing pin along the weld zone. The tool comprises: units for supporting and positioning workpieces (1a, 1b) so that the units are present in contact with an annular zone to be welded; a friction welding head that is movable in rotation around an axis perpendicular to an axis (A) of the workpieces and comprises a body and a mixing pin projecting relative to the welding head; a unit for radial displacement of the welding head compared to the worpieces to be assembled so as to penetrate the mixing pin on the annular zone to be welded or to withdraw the mixing pin from the zone to be welded; and a unit for rotating the workpieces relative to the welding head so as to move the mixing pin along the annular weld zone. The mixing pin is movably rotated compared to the body between a retracted position in which it is placed in the body and a deployed position in which it is covered out of the body. The supporting and positioning units comprise a first flange comprising a unit for centering one of the workpieces and a second flange comprising a unit for centering the other workpiece. The two flanges are mounted on a rotatable shaft so as to rotate the flanges and the workpieces relative to the welding head. The tool further comprises: a pressure member intended to bear on one of the workpieces to be assembled at or near the weld zone; a spacer for forcing the two flanges one towards the other so as to ensure the contact of the workpieces on the weld zone; and a brake (32) ready to slow down the rotation of the workpieces and to take support on an element of one of the workpieces. The pressure member is a turning roller resting against each of the workpieces to be assembled on the weld zone. Independent claims are included for: (1) a method for assembling two coaxial annular pieces to form a casing of a turbomachine by friction welding; and (2) a method for repairing a casing of a turbomachine.