Abstract: A tip rail cooling insert for attaching into a tip rail pocket in a tip rail of a turbine blade is disclosed. The insert includes a first inner layer defining at least one first insert cooling channel therein, the first inner layer including a pair of spaced legs defining a first coolant collection plenum with at least the tip rail pocket for directing coolant from at least one internal cooling cavity in the turbine blade to the at least one first insert cooling channel. Each of the pair of spaced legs has an angled outer end configured to accommodate rounded inner corners of the tip rail pocket. A first outer layer is on a first side of the first inner layer, and a second outer layer is on a second side of the first inner layer.

Abstract: A turbine blade tip cooling system includes a turbine blade having a tip cavity, a tip rail surrounding at least a portion of the tip cavity and at least one internal cooling cavity. The tip rail has an inner rail surface, an outer rail surface, an end surface and at least one tip rail pocket open at the end surface and fluidly connected to the at least one internal cooling cavity that carries a coolant. A tip rail cooling insert attaches to the at least one tip rail pocket, and has insert cooling channel(s) and a coolant collection plenum for directing coolant from the at least one internal cooling cavity to the insert cooling channel(s).

Abstract: A tip rail cooling insert for attaching into a tip rail pocket in a tip rail of a turbine blade is disclosed. The insert includes a first inner layer defining at least one first insert cooling channel therein, the first inner layer including a pair of spaced legs defining a first coolant collection plenum with at least the tip rail pocket for directing coolant from at least one internal cooling cavity in the turbine blade to the at least one first insert cooling channel. Each of the pair of spaced legs has an angled outer end configured to accommodate rounded inner corners of the tip rail pocket. A first outer layer is on a first side of the first inner layer, and a second outer layer is on a second side of the first inner layer.

Abstract: A turbine blade tip cooling system includes a turbine blade having a tip cavity, a tip rail surrounding at least a portion of the tip cavity and at least one internal cooling cavity. The tip rail has an inner rail surface, an outer rail surface, an end surface and at least one tip rail pocket open at the end surface and fluidly connected to the at least one internal cooling cavity that carries a coolant. A tip rail cooling insert attaches to the at least one tip rail pocket, and has insert cooling channel(s) and a coolant collection plenum for directing coolant from the at least one internal cooling cavity to the insert cooling channel(s).

Abstract: A hybrid diffusion-brazing process and hybrid diffusion-brazed article are disclosed. The hybrid diffusion-brazing process includes providing a component having a temperature-tolerant region and a temperature-sensitive region, brazing a braze material to the temperature-tolerant region during a localized brazing cycle, then heating the component in a furnace during a diffusion cycle. The brazing and the heating diffusion-braze the braze material to the component, and the localized brazing cycle is performed independent of the diffusion cycle in the hybrid diffusion-brazing process. The hybrid diffusion-brazed article includes a component, and a braze material diffusion-brazed to the component with a filler material. The filler material has a melting temperature that is above a tolerance temperature of the component.

Abstract: Blockages of turbomachine cooling circuit cooling holes resulting from coating processes can be removed by introducing a cleaning agent into the cooling circuit. The cooling circuit can be connected to a cleaning agent supply under pressure, adding force on the blockage to chemical action by the cleaning agent. The cleaning agent is chemically reactive with the coating material and substantially chemically non-reactive with the underlying material of the cooling circuit and other parts of the turbomachine. A neutralization agent can also be introduced to reduce toxicity and/or action of the cleaning agent. A turbomachine cooling hole cleaning method includes introducing a cleaning agent into a cooling circuit of a turbomachine part, pressurizing the cleaning agent in the cooling circuit until a first defined condition is met, and introducing a neutralization agent to the turbomachine part while the cleaning agent is applied to the cooling circuit.

Abstract: Blockages of turbomachine cooling circuit cooling holes resulting from coating processes can be removed by introducing a cleaning agent into the cooling circuit. The cooling circuit can be connected to a cleaning agent supply under pressure, adding force on the blockage to chemical action by the cleaning agent. The cleaning agent is chemically reactive with the coating material and substantially chemically non-reactive with the underlying material of the cooling circuit and other parts of the turbomachine. A neutralization agent can also be introduced to reduce toxicity and/or action of the cleaning agent. A turbomachine cooling hole cleaning method includes introducing a cleaning agent into a cooling circuit of a turbomachine part, pressurizing the cleaning agent in the cooling circuit until a first defined condition is met, and introducing a neutralization agent to the turbomachine part while the cleaning agent is applied to the cooling circuit.

Abstract: A modification process and modified article are disclosed. The modification process includes locating an area in an article, removing the area by machining to form a machined region, inserting a modification material into the machined region, securing the modification material to the article, machining the modification material flush with a geometry of the article, and applying a coating over at least a portion of the article. Another modification process includes locating an area under a suction side leading edge tip shroud fillet of an airfoil, removing the area by machining to form a hole, inserting a modification material having improved material properties as compared to an original base material into the hole, securing the modification material in place, machining the modification material and the airfoil to form a new fillet contour, and applying a coating over at least a portion of the airfoil. Also disclosed is the modified article.

Abstract: Blockages of turbomachine cooling circuit cooling holes resulting from coating processes can be removed by introducing a cleaning agent into the cooling circuit. The cooling circuit can be connected to a cleaning agent supply under pressure, adding force on the blockage to chemical action by the cleaning agent. The cleaning agent is chemically reactive with the coating material and substantially chemically non-reactive with the underlying material of the cooling circuit and other parts of the turbomachine. A neutralization agent can also be introduced to reduce toxicity and/or action of the cleaning agent.

Abstract: A system for performing remote welding operations on an apparatus is disclosed. The system may generally include a welding chamber configured to house the apparatus and a robotic welder positioned within the welding chamber. The robotic welder may be configured to perform an actual welding operation on the apparatus. In addition, the system may include a welding simulation device positioned outside the welding chamber and a controller communicatively coupled to the robotic welder and the welding simulation device. The welding simulation device may be configured to perform a simulated welding operation corresponding to the actual welding operation. The controller may be configured to track the movement of the welding simulation device and control the operation of the robotic welder based on the movements of the welding simulation device.

Abstract: A method for repairing a shroud tile of a gas turbine is disclosed. The method may generally include removing a portion of the shroud tile along at least one of a first side and a second side of the shroud tile and securing at least one side rail to the shroud tile in place of the removed portion of the shroud tile.

Abstract: Methods of reducing an initial cross-sectional area of a hole in a component to a predetermined cross-sectional area including preparing a composition comprising at least an aluminum alloy with a melting temperature higher than aluminum, applying the composition to an interior surface of the hole, and then heating the component to cause a metal within the component to diffuse from the component into the composition and react with the aluminum alloy in the composition to form a coating on the interior surface of the hole. The heating step is performed to selectively modify the initial cross-sectional area of the hole and thereby directly attain the predetermined cross-sectional area thereof.

Abstract: A fixture assembly for securing at least one side rail to a shroud tile of a gas turbine is disclosed. The fixture assembly may include a first support member, a second support member, a first guide block and a second guide block. The first and second guide blocks may be formed from a material that has the same or a similar coefficient of thermal expansion as the material used to form at least one of the shroud tile and the at least one side rail. In addition, the first and second support members may be formed from a material that has a lower coefficient of thermal expansion than the material used to form the first and second guide blocks.

Abstract: Automated polishing systems include a polisher for polishing the coating on the article and a robotic positioner for moving the polisher relative to the article on an automated path, wherein the polisher polishes at least a part of the coating during movement, a force feedback sensor for determining a force of the polisher against the article during polishing, and a controller for maintaining the polisher within a predetermined force range against the article based at least in part on the force determined by the force feedback sensor.

Abstract: A modification process and modified article are disclosed. The modification process includes locating an area in an article, removing the area by machining to form a machined region, inserting a modification material into the machined region, securing the modification material to the article, machining the modification material flush with a geometry of the article, and applying a coating over at least a portion of the article. Another modification process includes locating an area under a suction side leading edge tip shroud fillet of an airfoil, removing the area by machining to form a hole, inserting a modification material having improved material properties as compared to an original base material into the hole, securing the modification material in place, machining the modification material and the airfoil to form a new fillet contour, and applying a coating over at least a portion of the airfoil. Also disclosed is the modified article.

Abstract: Composite electro-spark electrodes, along with methods of their use in an electro-spark deposition process, are provided. The composite electro-spark electrode can include an electrode tip that is mechanically and electrically attached to a shank. The shank comprises a resistive material, and the electrode tip comprises a metal, with the metal of the electrode tip being less electrically resistive than the resistive material of the shank. Additionally, the metal of the electrode tip can be more thermally conductive than the resistive material of the shank.

Abstract: A hybrid diffusion-brazing process and hybrid diffusion-brazed article are disclosed. The hybrid diffusion-brazing process includes providing a component having a temperature-tolerant region and a temperature-sensitive region, brazing a braze material to the temperature-tolerant region during a localized brazing cycle, then heating the component in a furnace during a diffusion cycle. The brazing and the heating diffusion-braze the braze material to the component, and the localized brazing cycle is performed independent of the diffusion cycle in the hybrid diffusion-brazing process. The hybrid diffusion-brazed article includes a component, and a braze material diffusion-brazed to the component with a filler material. The filler material has a melting temperature that is above a tolerance temperature of the component.

Abstract: Methods for modifying a turbine buckets include removing at least an original outer edge for an entire length of the slash face of the turbine bucket and adding a new material to the slash face to build a new outer edge, wherein the new outer edge extends the entire length of the slash face.

Abstract: Methods for joining material to an article comprising one or more passageways include fluidly connecting a temperature controlled fluid source comprising temperature controlled fluid to at least one passageway and passing the temperature controlled fluid through the at least one passageway, wherein the temperature controlled fluid at least partially controls a temperature profile of the article. The methods further include joining material to the article, wherein the temperature profile of the article at least partially controls a resulting joined material characteristic.

Abstract: Systems and methods of treating, e.g., stripping and coating, a target surface of an article including a passageway are disclosed. The systems may fluidly connect a pressure masker including pressurized masking fluid to a first side of the passageway, passing the pressurized masking fluid through the passageway from the first side to a second side including the target surface, and, submerging at least a portion of the target surface in a treatment bath, wherein the pressurized masking fluid passing through the passageway prevents the treatment bath from entering the passageway.