Turbine for a turbine engine

A turbine 1 comprising a rotor including blades 38, the radial tips of which each include at least one radially extending wiper 39. A ring made of abradable material radially extends around the blades and cooperate with the wipers to form a labyrinth seal. The ring includes a first portion 20, which axially extends upstream of the wiper, and a second portion 21, different from the first, which axially extends downstream of the wiper. The first portion and/or second portion include a groove 23, 31 in which the wiper has been inserted, the groove being defined by both the first portion and the second portion. Each ring portion may include a block of abradable material 22, 30 mounted on an annular support 24, 32, with each support including an U-shaped attachment member 27, 35 which cooperates with a flange 4, 5 of the turbine casing 2. Also claimed is a method for assembling the turbine, including mounting the first and second portions of the ring on the casing through axial engagement in the upstream direction of the respective portions relative to the casing, mounting the impeller 38 in the casing, and introducing the first wiper into the groove during mounting of the impeller of the second portion.