Patent ID: 8371807

Claim:
A protection device for a stator of a turbine comprising: a series of annular sectors constrained to each other by a connector, each sector of said series of sectors comprises a first surface, suitable for contacting said stator which has at least one cavity for the cooling of the corresponding sector; and a second surface which faces a rotor of the turbine, wherein in a rest configuration in which the turbine is not operating, said second surface of each sector has an axial section having an eccentricity with respect to a trace of a rotation axis of said turbine to provide a radial clearance in both an axial and a circumferential direction with respect to the trace of the rotation axis of said turbine; and wherein in an operating configuration in which said turbine is operating under regime conditions, in which the turbine is affected by non-uniform thermal gradients, said second surface of each sector is configured to deform, based on the non-uniform thermal gradients, in each of the axial and circumferential directions such that an axial section is centered with the trace of the rotation axis of said turbine; wherein due to the axial deformation, a loss of air between the protection device and a rotor blade is minimized in the axial direction.