Patent ID: 8727719

Claim:
A radial annular flange of a turbomachine turbine, the flange having an axis around which axis the flange extends and comprising: at an inner periphery, alternating solid portions and hollow portions, the solid portions including orifices for passing fastener bolts, the hollow portions comprising a first hollow portion, a second hollow portion, and third hollow portions, each of the hollow portions having a bottom, the bottoms of first and second hollow portions being substantially flat, wherein the second hollow portion comprises a keying system formed by its flat bottom that is situated radially on the inside of a circle centered on the axis of the flange and externally tangential to the orifices in the solid portions, wherein the third hollow portions are situated on either side of said second hollow portion and present bottoms of concave curved shapes situated radially on the outside relative to the bottoms of the first and second hollow portions, and wherein the bottom of the first hollow portion is situated radially on the outside relative to the circle externally tangential to the orifices of the solid portions.