Turbine stage in a turbine engine

Abstract

A turbine stage for a turbine engine includes a bladed wheel rotatable inside a sectorized ring of composite material carried by a casing. Each ring sector has a downstream circumferential rim held to bear radially against an annular tab that is engaged radially in an annular groove of the downstream circumferential rim of the ring with axial clearance, when cold, that is designed to be reduced to zero in operation when hot, and to enable the annular tab of the casing to be clamped axially in leaktight manner in the annular groove of the ring sector.

1 - 6 . (canceled) 
     
     
         7 . A turbine stage for a turbine engine, the stage comprising:
 a bladed wheel rotatable inside a sectorized ring made of composite material and carried by a casing, each ring sector having a downstream circumferential rim held to bear radially against an annular tab of the casing by a C-section fastener,   wherein the annular tab of the casing is engaged radially in an annular groove in the downstream circumferential rim of the ring with axial clearance, when cold, that is designed to be reduced to zero in operation, when hot, and to enable leaktight axial clamping of the annular tab of the casing in the annular groove of the ring sector.   
     
     
         8 . The turbine stage according to  claim 7 , wherein the annular tab of the casing has upstream and downstream radial faces for bearing when hot against radial flanks of the groove. 
     
     
         9 . The turbine stage according to  claim 7 , wherein the axial clearance when cold is of the order of one-tenth of a millimeter. 
     
     
         10 . The turbine stage according to  claim 7 , wherein an annular sealing ring is housed in an annular groove in the face of the annular tab that is pressed against the bottom wall of the annular groove in the ring sector. 
     
     
         11 . The turbine stage according to  claim 7 , wherein the composite material is of the ceramic matrix type and the casing is made of a metal material. 
     
     
         12 . A turbine engine such as an airplane turboprop or turbojet, wherein the engine includes the turbine stage according to  claim 7 .