Abstract: A method for extending the life of the attachments that attach blades to rotors, particularly for aerojet engines. Such a method is notable in that it employs intensive ultrasonic peening of the grooves and of the roots of the blades, this peening being performed with an Almen intensity at least equal to F8A, so as to increase the compressive prestress in the contact surfaces without increasing the roughness of these surfaces.

Abstract: The invention relates to a method for the ultrasonic peening of annular recesses for the attachment of blades to a rotor rim, these recesses including a blade introduction opening. According to the method, a plurality of beads is placed on a vibratory surface of a sonotrode, arranged in an intermediate position in a sleeve having opposed closing-off means capable of sliding in the recess, the introduction opening is placed facing the sonotrode, the sonotrode and the sleeve are moved together toward the introduction opening into a peening position in which the closing-off means face the recess ends opening into said opening, then the rotor rim is turned about its axis so as to bring the closing-off means into a first end of the recess so as to form a closed chamber containing the beads. The rim is turned and the vibratory surface is vibrated to mobilize the beads within the chamber, thereby peening the recess.

Abstract: The invention relates to an apparatus and to a method for the surface treatment and compressive prestressing by peening of a wall of at least one oblong cavity formed in a part, said cavity opening to the outside via a lateral mouth and having two ends presenting frontal openings. The wall of the cavity is ultrasonically peened by mobilizing a plurality of beads in a chamber delimited by said wall of said cavity, a vibratory surface closing off said mouth of said cavity, and closing-off means closing off said openings, by means of a sonotrode excited by means for producing ultrasonic oscillations. The method and the apparatus are particularly intended for treating a turbine disk comprising a number of axial recesses formed in the periphery of said disk and having wall portions which diverge from each mouth.

Abstract: A method for peening the tops of cooled blades which include cooling air passage orifices. Peening is performed by mobilization of a plurality of beads in a sealed chamber containing at least one blade tip. The plurality of beads is mobilized by the active surface of a sonotrode which delimits part of said chamber. The beads have a diameter greater than that of the cooling air passage orifices.

Abstract: A method for extending the life of the attachments that attach blades to rotors, particularly for aerojet engines. Such a method is notable in that it employs intensive ultrasonic peening of the grooves and of the roots of the blades, this peening being performed with an Almen intensity at least equal to F8A, so as to increase the compressive prestress in the contact surfaces without increasing the roughness of these surfaces.

Abstract: The invention relates to a method for the ultrasonic peening of annular recesses for the attachment of blades to a rotor rim, these recesses including a blade introduction opening. According to the method, a plurality of beads is placed on a vibratory surface of a sonotrode, arranged in an intermediate position in a sleeve having opposed closing-off means capable of sliding in the recess, the introduction opening is placed facing the sonotrode, the sonotrode and the sleeve are moved together toward the introduction opening into a peening position in which the closing-off means face the recess ends opening into said opening, then the rotor rim is turned about its axis so as to bring the closing-off means into a first end of the recess so as to form a closed chamber containing the beads. The rim is turned and the vibratory surface is vibrated to mobilize the beads within the chamber, thereby peening the recess.

Abstract: The invention relates to an apparatus and to a method for the surface treatment and compressive prestressing by peening of a wall of at least one oblong cavity formed in a part, said cavity opening to the outside via a lateral mouth and having two ends presenting frontal openings. The wall of the cavity is ultrasonically peened by mobilizing a plurality of beads in a chamber delimited by said wall of said cavity, a vibratory surface closing off said mouth of said cavity, and closing-off means closing off said openings, by means of a sonotrode excited by means for producing ultrasonic oscillations. The method and the apparatus are particularly intended for treating a turbine disk comprising a number of axial recesses formed in the periphery of said disk and having wall portions which diverge from each mouth.