Abstract: A method of repairing a damaged rotor comprising: (a) preparing a locally damaged portion of the rotor; (b) cold spraying alloy powder particles onto the locally damaged portion; (c) controlling the cold spraying in step (b) to restore the locally damaged portion to form a repaired portion having substantially the same properties and shape as originally manufactured; and (d) heat treating at least the repaired portion.

Abstract: A method of repairing a damaged rotor comprising: (a) preparing a locally damaged portion of the rotor; (b) cold spraying alloy powder particles onto the locally damaged portion; (c) controlling the cold spraying in step (b) to restore the locally damaged portion to form a repaired portion having substantially the same properties and shape as originally manufactured; and (d) heat treating at least the repaired portion.

Abstract: A method of manufacturing a rotor includes: (a) providing a core shaft; (b) cold spraying alloy powder particles onto the core shaft; (c) controlling the cold spraying to form sections at least of different shape along the core shaft to thereby form a near-net shape rotor; and (d) heat treating the near-net shape rotor to relieve stresses and to form diffusion bonding across interfaces between individual powder particles and the core shaft, and finish-shaping said near-net shape rotor.

Abstract: A method operates a gas turbine that includes a compressor section, a turbine section and an extraction cooling system. The method includes monitoring an operation of the gas turbine, directing a cooling air flow through the extraction cooling system from the compressor section to the turbine section in response to normal operation of the gas turbine, and directing a warming air flow through the extraction cooling system to the compressor section and the turbine section in response to shutdown of the gas turbine.

Abstract: A method of manufacturing a rotor includes: (a) providing a core shaft; (b) cold spraying alloy powder particles onto the core shaft; (c) controlling the cold spraying to form sections at least of different shape along the core shaft to thereby form a near-net shape rotor; and (d) heat treating the near-net shape rotor to relieve stresses and to form diffusion bonding across interfaces between individual powder particles and the core shaft, and finish-shaping said near-net shape rotor.

Abstract: A method operates a gas turbine that includes a compressor section, a turbine section and an extraction cooling system. The method includes monitoring an operation of the gas turbine, directing a cooling air flow through the extraction cooling system from the compressor section to the turbine section in response to normal operation of the gas turbine, and directing a warming air flow through the extraction cooling system to the compressor section and the turbine section in response to shutdown of the gas turbine.

Abstract: A flowpath ring is securable in a machined groove of a gas turbine compressor stator casing. The ring includes a connector section engageable with and shaped corresponding to the machined groove. A flowpath section is disposed radially inward relative to the connector section and includes a clearance surface disposed facing a turbine rotor blade. The flowpath section defines a blade flowpath when secured in the turbine stator casing machined groove. The use of flowpath rings facilitates flowpath repair if rotor blade tip rubs occur. Additionally, the rings enable better matching of transient thermal responses between the compressor rotor and compressor casings.

Abstract: A method of attaching a shroud cover segment to a plurality of gas turbine compressor stator vanes includes: (a) forming each of the plurality of stator vanes with at least one tenon extending from a radially inner tip of each of the stator vanes; (b) forming the shroud cover segment with at least one aperture for each of the at least one tenon; (c) locating the plurality of stator vanes and the shroud cover segment such that the at least one tenon of each of the stator vanes projects through a respective aperture in the shroud cover; and (d) forming the at least one tenon of each of the plurality of stator vanes to create an enlarged tenon head on each of the tenons, thereby fixing the shroud cover segment to the plurality of stator vanes.