Blade Retaining Ring for an Internal Shroud of an Axial-Flow Turbomachine Compressor

A compressor of an axial-flow turbomachine, comprising:

• a stator comprising:
• an outer casing;
• an inner shroud having an annular row of openings and guiding an annular primary flow of the compressor;
• an annular row of stator blades which extend essentially radially from the outer casing to the inner shroud and passing through the openings, each blade including an inner fixation extremity with retaining slot and a blade leaf extending in the primary flow of the compressor, each retaining slot including an inlet having a taper and being situated on the other side of the blade leaf in relation to the opening passed through by the corresponding blade;
• and
• at least one retaining ring for blades inserted into the slots, the ring exhibiting the form of a strip having an arched transversal profile which is in contact with the tapers in such a way as to maintain the ring in the slots;
• wherein the shroud comprises:
• a layer of abradable material enclosing the transversal profile of the ring in such a way as to block the curvature of the arched transversal profile in order to prevent the ring from exiting from the tapers of the slots by being deformed, the abradable layer further enclosing the inner fixation extremities of the blades.

An axial-flow turbomachine, comprising:

• a rotor;
• and
• a stator comprising:
• a shroud having an annular row of openings;
• an annular row of stator blades which extend essentially radially by passing through the openings, each blade including a retaining slot and a blade leaf intended to extend in a flow of the turbomachine, each retaining slot including an inlet having a taper and being situated on the other side of the blade leaf in relation to the opening passed through by the corresponding blade;
• and
• at least one retaining ring for blades inserted into the slots, the ring exhibiting the form of a strip having an arched transversal profile which is in contact with the tapers in such a way as to maintain the ring in the slots;
• wherein the shroud comprises:
• a layer of abradable material enclosing the transversal profile of the ring in such a way as to block the curvature of the arched transversal profile in order to prevent the ring from exiting from the tapers of the slots by being deformed, the abradable layer comprising:
• an annular surface around the rotor which is facing said rotor.