An assembly for gas turbine, includes a first part and a second part installed circumferentially around a longitudinal axis of the turbine, where the first part has a first side face adjacent to a second side face of the second part, and where a first aperture made in first side face is facing a second aperture made in second side face, a sealing plate fitted inside the first aperture and the second aperture, at least one longitudinal face of the sealing plate includes at least two projections made either side of a longitudinal central area of the sealing plate, wherein each projection is of a height chosen so as to reduce a clearance between the sealing plate and the first and second apertures.