Abstract: A damper pin for a turbine bucket includes an elongated main body portion of substantially uniform cross-sectional shape having opposite ends, one only of said opposite ends coated with a corrosion and oxidation-resistant coating.

Abstract: Methods and apparatus for cooling rotor blades of a gas turbine are provided. The turbine blade has an airfoil connected to the platform and a dovetail extending from the platform. A main cooling circuit extends through the dovetail and into the airfoil. The main cooling circuit includes an exit for main cooling flow from the airfoil to exit out through the dovetail. In one aspect, the method includes the steps of extracting a portion of the coolant flowing through the main cooling circuit into a platform cooling circuit. After cooling a portion of the platform, the platform cooling flow splits with one portion of the flow rejoining the main cooling circuit and is used to cool the airfoil. The rest of the platform cooling flow continues to cool the platform and then returns to the main cooling circuit to flow through the exit.

Abstract: A damper pin for a turbine bucket includes an elongated main body portion of substantially uniform cross-sectional shape having opposite ends, one only of said opposite ends coated with a corrosion and oxidation-resistant coating.

Abstract: A weld process cuitable for repairing precipitation-strengthened superalloys, and particularly gamma prime-strengthened nickel-based superalloys. The process entails forming a weldment in a cavity present in a surface of an article formed of a precipitation-strengthened superalloy. The cavity has a root region and a cap region between the root region and the surface of the article. A solid body formed of a superalloy composition is placed in the root region of the cavity so as to occupy a first portion but not a second portion of the root region. A first filler material formed of a solid solution-strengthened superalloy is then weld-deposited in the second portion of the root region. Subsequently, a second filler material formed of a precipitation-strengthened superalloy is weld-deposited in the cap region of the cavity.

Abstract: A turbine component includes a plurality of film-cooling holes formed in a region of the component to be cooled, the cooling holes having specified diameter, each hole at an exit thereof formed with a counter-bore of predetermined depth; the component having a coating applied thereto at least in the region, wherein the counter-bore provides an area for excess coating material to accumulate without reducing the specified diameter. A method of maintaining cooling efficiency of film-cooling holes in a turbine component where the film-cooling holes have specified diameters and the turbine component has a protective coating therein comprising: a) before coating, forming each film-cooling hole with a counter-bore and an exit end of the film-cooling hole; and b) spraying the coating onto the turbine component at least in areas surrounding the film-cooling holes such that excess coating material accumulates in the counter-bore without reducing the specified diameter of the cooling holes.