Gas turbine combustor and gas turbine

Abstract

The present invention reduces thermal stress that is applied to the weld zone of a cavity formed in the structural material of a burner. The burner includes the cavity distributing a fuel to fuel nozzles. The cavity is demarcated by a groove formed in the structural material of the burner so as to create a level difference at an opening, and a cover fitted into the level difference to close the groove. The cover is formed by a web covering the opening in the groove and a flange extending in the depth direction of the groove to be fitted into the level difference, and is joined by welding to the structural material in such a manner as to have an L-shaped cross-section. When viewed in a cross-section orthogonal to the groove, a cover-side inner surface that is an inner surface of the flange forming a lateral surface of the cavity is flush with a groove-side inner surface that is an inner surface of the groove forming a lateral surface of the cavity. The boundary between the cover-side inner surface and the groove-side inner surface is away from a first corner of the cavity sandwiched between the cover-side inner surface and the inner surface of the web forming a ceiling surface of the cavity.