Device and method for repairing a damaged zone of an intermediate layer of a multilayer structure by way of deformable corrugated rings

A method for repairing a damaged and removed zone at the periphery of a first cavity that has a first diameter and is defined in an intermediate layer interposed between at least two layers that have a second cavity with a second diameter smaller than said first diameter, said second cavity being coaxial with said first cavity, comprising the steps:

• defining an abutment at an interface between said first cavity and said second cavity in one of said layers,
• installing in said first cavity at least one ring that has a deformable corrugated shape, an initial inside diameter, and an initial outside diameter smaller than said second diameter,
• introducing into said first cavity, by means of a tool, a deformation means that has an elastically variable outside diameter initially smaller than an inside diameter of said ring, and
• increasing the outside diameter of said deformation means by way of said tool in order to deform said ring in said first cavity by increasing its initial outside diameter so as to reduce the difference between said first and second diameters.

A method of repairing a multilayer structure of an aircraft comprising a damaged and removed zone at the periphery of a first cavity that has a first diameter and is defined in an intermediate layer interposed between at least two layers that have a second cavity with a second diameter smaller than said first diameter, said second cavity being coaxial with said first cavity, the method comprising steps of

• using a repairing device comprising:
• a stop means having a surface defining an abutment for an interface between said first cavity and said second cavity in one of said layers,
• at least one ring having a deformable corrugated shape, an initial inside diameter, an initial outside diameter smaller than said second diameter, and being intended to be positioned in said first cavity,
• a deformation means having a central cavity and an elastically variable outside diameter initially smaller than said initial inside diameter of said ring, and
• a tool being designed to be introduced into said central cavity and to increase the outside diameter of said deformation means in order to deform said ring in said first cavity by increasing its initial outside diameter so as to reduce the difference between said first and second diameters, and
• defining an abutment at an interface between said first cavity and said second cavity in one of said layers,
• installing in said first cavity at least one ring that has a deformable corrugated shape, an initial inside diameter, and an initial outside diameter smaller than said second diameter,
• introducing into said first cavity, by means of a tool, a deformation means that has an elastically variable outside diameter initially smaller than an inside diameter of said ring, and
• increasing the outside diameter of said deformation means by way of said tool in order to deform said ring in said first cavity by increasing its initial outside diameter so as to reduce the difference between said first and second diameters.