1. Field of the Invention
The present invention relates to a gas turbine in which the turbine is rotated by high-temperature gas produced by mixing and burning compressed air and fuel, to obtain rotative power.
2. Description of Related Art
When comparing gas turbines with other power units that are similar in weight and volume of the unit body, the gas turbines have advantages such as higher output and fast start-up capabilities. Currently, the gas turbines are used in various fields, such as engines of aircrafts or vessels and power generation facilities.
The gas turbines are mainly constituted by a compressor, a combustor, and a turbine, and the turbines are classified into axial-flow turbines and radial-flow turbines according to the difference in the flow direction of high-temperature gas in this turbine.
An example of the gas turbines using the axial-flow turbine is disclosed in Japanese Unexamined Patent Application, First Publication No. 2011-38491. In this axial-flow turbine, blade rings are continuously fixed toward the direction of a rotating shaft so as to form an annular shape on the inner peripheral side of a casing that forms an outline. Additionally, ring segments are supported via isolation rings on the inner peripheral side of this blade ring, the ring segments are arranged in an annular shape with gaps in the direction of the rotating shaft of the axial-flow turbine, and the vanes are fixed in the gaps. Since blades are provided between the vanes in the direction of the rotating shaft, that is, at positions corresponding to the ring segments, the vanes and the blades are alternately arranged in the direction of the rotating shaft.
Moreover, supporting members that connect the ring segments and the isolation rings with the blade rings from the direction of the rotating shaft, and regulate movement of the ring segments and the isolation rings are provided at the end faces of the blade rings in the direction of the rotating shaft.
However, in the gas turbine in Japanese Unexamined Patent Application, First Publication No. 2011-38491, as high-temperature gas flows into a gap between adjacent blade rings, a high-temperature oxidation reaction is triggered in the blade ring around the supporting member, and the thickness of the blade ring may decrease.
The present invention has been made in consideration of such circumstances, and an object thereof is to provide a repairing method of a gas turbine and a gas turbine that can suppress reduction in the thickness of a blade ring.