Patent ID: 8137055

Claim:
A turbine stator blade for a gas turbine, comprising: a blade root; a platform section arranged on the blade root; a hollow blade airfoil arranged on the platform section having an interior wall surface that defines an interior portion of the hollow blade airfoil; a sheet metal-form impingement cooling insert arranged in the hollow blade airfoil that separates the interior cavity to form an interspace portion and a cooling medium passage, the interspace portion defined as a rectilinearly extending gap between the interior wall surface and the cooling insert; and a plurality of cooling impingement holes arranged in the impingement cooling insert, wherein a cooling medium flows from the cooling medium passage into the interspace portion, wherein the cooling insert comprises a plurality of cooling insert sections arranged one upon the other overlapping in an overlap area having a wave-like cross section and extending parallel to the rectilinear gap, wherein for sealing the overlap area the cooling insert sections are displaced in such a way that in the overlap area a contact surface is formed, the contact surface extends rectilinearly.