Abstract: A cooling assembly includes a cooling chamber disposed inside of a turbine assembly. The cooling chamber directs cooling air inside an airfoil of the turbine assembly. The cooling assembly includes a metered channel fluidly coupled with the cooling chamber. The metered channel directs at least some of the cooling air out of the cooling chamber outside of a rail surface of the airfoil. The metered channel is elongated along and encompasses an axis. The metered channel has an interior surface with a distance between opposing first portions of the interior surface. The distance between the opposing first portions decreases at increasing distances along the axis from the cooling chamber toward the rail surface.

Abstract: A cooling assembly includes a cooling chamber disposed inside of a turbine assembly. The cooling chamber directs cooling air inside an airfoil of the turbine assembly. The cooling assembly includes a metered channel fluidly coupled with the cooling chamber. The metered channel directs at least some of the cooling air out of the cooling chamber outside of a rail surface of the airfoil. The metered channel is elongated along and encompasses an axis. The metered channel has an interior surface with a distance between opposing first portions of the interior surface. The distance between the opposing first portions decreases at increasing distances along the axis from the cooling chamber toward the rail surface.

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 bucket for a steam turbine includes an airfoil portion having a radially outer tip, the radially outer tip having a thermal barrier coating applied thereto, and wherein the thermal barrier coating is resurfaced to form at least one ridge along the radially outer tip.

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: In a turbine bucket having an airfoil portion and a root portion with a substantially planar platform at an interface between the airfoil portion and the root portion, a platform cooling arrangement including a cavity extending along the forward portion of the platform, and at least one inlet bore extending from a source of cooling medium to the cavity, and at least one outlet opening for expelling cooling medium from the cavity.

Abstract: A tip cap piece for use in a turbine bucket. The tip cap piece may include a cold side and a number of pins positioned on the cold side.

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 nozzle assembly (10) for a turbine engine includes an inner band (16) and an outer band (14) spaced apart from each other. An airfoil (12) installed between the bands has a leading edge (18) and a trailing edge (20). The airfoil has cavities formed in it for fluid flow through the nozzle assembly. A plurality of film cooling holes (1A–6H) are formed in a sidewall of the airfoil on a concave side of the assembly, and a plurality of film cooling holes (1J–1R) are formed in a sidewall of the nozzle on a convex side thereof. The holes are formed on each side of the airfoil, adjacent the trailing edge of the nozzle, in a plurality of rows of holes including at least a forward row (C, J), an aft row (A, L), and an intermediate row (B, K). The spacing between the intermediate row and aft row is substantially closer than the spacing between the forward row and the intermediate row.

Abstract: A cooling insert/nozzle assembly for use in gas turbines or similar machinery includes a nozzle having inner and outer ribs with cast-in “T” sections and “L” sections, respectively, at the end of the ribs in which air flow enters the nozzle. The assembly further includes a cooling insert having a flexible end which is inserted between adjacent ribs having either the cast-in “T” or “L” sections.

Abstract: Grooves are formed along portions of the side edges of a turbine bucket platform and open through the side edges of the surface of the platform exposed to the hot gas path of the turbine. A bond coat is applied to the groove followed by a thermal barrier coating which is preferably plasma sprayed onto the bond coat. The thermal barrier coating thickness protects the coating beyond the surface of the bare metal of the platform side and is then abraded or ground to lie flush with the bare metal surface. Thus, the side faces of the platform have a thermal barrier coating to reduce oxidation.

Abstract: Damper pins are disposed in circumferentially registering grooves of turbine bucket platform slash faces. The pins have a plurality of channels formed about peripheral portions thereof for flowing leakage cooling air from below the platform past the pin and groove into the interplatform gap. The channels may be staggered in an axial direction. By flowing cooling air through the channels, the slash faces are convectively cooled, opposite slash faces to the channels are impingement cooled and the exiting cooling air purges the gap between the slash faces adjacent the hot gas path. Alternatively, the channels may be formed in the grooved surfaces and a cylindrical damping pin may be inserted with similar cooling effects.

Abstract: The cooling system includes a plurality of generally radially extending passages within the airfoil for convectively cooling the airfoil. A predetermined number of the passages exit through the airfoil tip. One or more of the remaining passages exit into a plenum adjacent the trailing edge and airfoil tip region of the airfoil and flow radially inwardly along one or more passageways adjacent the trailing edge region. The passageways exit in openings along the pressure side of the airfoil. In this manner, the trailing edge region is convectively cooled as well as film cooled by the film of air exiting the holes.

Abstract: A turbine bucket includes a platform interfacing between an airfoil and a shank. The platform is provided with a plurality of cavities covered by impingement cooling plates along the platform underside. Purge air supplied in the gaps between adjacent buckets flows through holes in the impingement plates to impingement cool opposite wall portions of the platform. The cooling air in the cavities is transmitted through film cooling holes in the platform to form a thin film of insulating air along the surface of the platform exposed to the hot gas in the hot gas path.

Abstract: A bucket has an airfoil, a root and a platform between the root and airfoil. The airfoil includes a serpentine cooling circuit, and the platform includes plural cavities, one or more cavities each having a serpentine cooling circuit. Cooling medium is drawn from one of the passages of the airfoil cooling circuit for flow in the platform cooling circuit and for return either to another passage of the airfoil circuit or to a trailing edge exit. The platform cooling circuits thus convectively cool both high and low pressure sides of the platform.

Abstract: A secondary datum scheme is used for identifying the location of the core-produced internal geometry of hollow investment cast metal parts that are made using a free-floating core design for implementing complex internal structural features. A set of datum pads are cast on a removable portion of the core print out to provide the secondary reference system. This secondary reference system precisely establishes the location of the core-produced internal geometry of the part exclusive of any fixed external primary datum structure/system so that, for example, precision machining and gauging may be performed upon such internal features during subsequent fabrication steps.

Abstract: A nozzle assembly (10) for a turbine engine includes an inner band (16) and an outer band (14) spaced apart from each other. An airfoil (12) installed between the bands has a leading edge (18) and a trailing edge (20). The airfoil has cavities formed in it for fluid flow through the nozzle assembly. A plurality of film cooling holes (1A-6H) are formed in a sidewall of the airfoil on a concave side of the assembly, and a plurality of film cooling holes (1J-1R) are formed in a sidewall of the nozzle on a convex side thereof. The holes are formed on each side of the airfoil, adjacent the trailing edge of the nozzle, in a plurality of rows of holes including at least a forward row (C, J), an aft row (A, L), and an intermediate row (B, K). The spacing between the intermediate row and aft row is substantially closer than the spacing between the forward row and the intermediate row.

Abstract: The invention comprises a metering plate which is assembled to an impingement insert for use in the nozzle of a gas turbine. The metering plate can have one or more metering holes and is used to balance the cooling flow within the nozzle. A metering plate with multiple holes reduces static pressure variations which result from the cooling airflow through the metering plate. The metering plate can be assembled to the insert before or after the insert is inserted into the nozzle.

Abstract: The invention comprises a metering plate which is assembled to an impingement insert for use in the nozzle of a gas turbine. The metering plate can have one or more metering holes and is used to balance the cooling flow within the nozzle. A metering plate with multiple holes reduces static pressure variations which result from the cooling airflow through the metering plate. The metering plate can be assembled to the insert before or after the insert is inserted into the nozzle.