Abstract:
A method of extending the useable life of a gas turbine component fabricated from a cobalt-based alloy is disclosed. The method includes applying a rejuvenation process to the alloy where the alloy is placed in a protected atmosphere and heated to three different elevated temperatures and held at the elevated temperatures for approximately four hours each. Application of the rejuvenation process allows gas turbine components to be returned to service for at least one more service interval of approximately 24,000 operating hours.
Abstract:
Known protective layers having a high Cr content, as well as silicon, have brittle phases that become additionally brittle under the influence of carbon during use. A protective layer that has the composition of 32% to 35% cobalt, 10% to 13% aluminum, 0.1% to 0.3% yttrium, and/or at least one equivalent metal from the group comprising scandium and the rate earth elements, 31% to 35% chromium, 0.1% to 0.5% silicon and the remainder nickel is provided.
Abstract:
The invention relates to a turbine blade with a cover plate shaped onto the pan of the blade. The aim of the invention is to provide a turbine blade of this type that, while having a high level of efficiency, is designed for a particularly reliable and safe operation in a turbine, particularly of a steam turbine. To this end, the invention provides that a protective layer made on an alternative material is applied to the surface of the cover plate facing away from the pan of the blade. The friction behavior with regard to a turbine component, particularly a sealing strip, which is opposite the protective layer, can be specifically influenced whereby enabling favorable emergency running properties to be provided in the event of rubbing.
Abstract:
A method for repairing a steel alloy article, and an article repaired thereby, is provided and comprises the steps of depositing at least a first weld repair layer on a surface of the article so as to form a heat affected zone in the article beneath the surface. Locally heat treating the first weld repair layer and at least a portion of the heat affected zone adjacent the first weld repair layer at a temperature above the critical A1 temperature of the steel alloy article. Depositing at least one additional weld repair layer on the first weld repair layer without forming additional heat affected zone in the surface of the article. The first weld repair layer and the at least one additional weld repair layer are comprised of a material chosen from the group consisting of nickel chromium—iron alloys, cobalt base alloys, ERNiCr-3, ENiCrFe-3, ERNiCrMo-3, ERNiFeCr-2, ERCoCr-A, ERCoCr-E, CrMo alloys and CrMoV alloys. The article can be placed in service without a post-weld heat treatment of the additional weld repair layer following the step of depositing the additional weld repair layer.
Abstract:
A reaction control turbine blade is formed by applying a reaction control material to the surface of an Ni-base superalloy before applying aluminum diffusion coating to the Ni-base superalloy. The reaction control material is Co, Cr or Ru, or an alloy of which main component is selected from a group consisting of Co, Cr, Ru. Thereby, it is possible to enhance the oxidation resistance of the Ni-base superalloy, and to control formation of a secondary reaction zone.
Abstract:
A piston ring for use at temperatures above 350° F. at pressures greater than or equal to about 2000 psi, comprising a gap having a gap width about 1.4 to about 2.0 times greater than a thickness of the piston ring; a height about 4.5 to about 6.4 times larger than the thickness, and a leading edge characterized by an arc having a radius of curvature of less than or equal to about 4 times the height. The piston ring may be formed of a material comprising cobalt, chromium, tungsten, and carbon. A gas compressor and method of sealing a piston using the above piston ring is also provided for.
Abstract:
A combustion turbine component (10) includes a combustion turbine component substrate (16) and an alloy coating (14) on the combustion turbine component substrate. The alloy coating (14) includes a first amount, by weight percent, of cobalt (Co) and a second amount, by weight percent, of nickel (Ni), the first amount being greater than the second amount. The alloy coating further includes chromium (Cr), aluminum (Al), at least one rare earth element, and an oxide of the at least one rare earth element.
Abstract:
The present invention provides a turbofan engine including leading edge erosion protection for composite stator vanes contained therein. The composite stator vanes are defined by a leading edge, a trailing edge, a concave surface and a convex surface. The vanes are generally formed of a graphite fiber and an aramid fiber braided preform that is laminated with an epoxy matrix resin or other high temperature matrix resin. A wire mesh screen is embedded during a molding process into an outermost surface of the leading edge of the epoxy matrix resin. A tapering erosion protection layer comprised of an erosion protective material is applied to the wire mesh screen at the leading edge of the composite stator vane an aids in protecting the leading edge of the stator vane from debris and contaminants, including operational fluids, dust, and sand that may be carried in an air stream passing therethrough the turbofan engine, as well as an erosive operational environment.
Abstract:
An erosion resistant protective structure for a turbine engine component comprises a shape memory alloy. The shape memory alloy includes nickel-titanium based alloys, indium-titanium based alloys, nickel-aluminum based alloys, nickel-gallium based alloys, copper based alloys, gold-cadmium based alloys, iron-platinum based alloys, iron-palladium based alloys, silver-cadmium based alloys, indium-cadmium based alloys, manganese-copper based alloys, ruthenium-niobium based alloys, ruthenium-tantalum based alloys, titanium based alloys, iron-based alloys, or combinations comprising at least one of the foregoing alloys. Also, disclosed herein are methods for forming the shape memory alloy onto turbine component.
Abstract:
The present invention provides a turbofan engine including leading edge erosion protection for composite stator vanes contained therein. The composite stator vanes are defined by a leading edge, a trailing edge, a concave surface and a convex surface. The vanes are generally formed of a graphite fiber and an aramid fiber braided preform that is laminated with an epoxy matrix resin or other high temperature matrix resin. A wire mesh screen is embedded during a molding process into an outermost surface of the leading edge of the epoxy matrix resin. A tapering erosion protection layer comprised of an erosion protective material is applied to the wire mesh screen at the leading edge of the composite stator vane an aids in protecting the leading edge of the stator vane from debris and contaminants, including operational fluids, dust, and sand that may be carried in an air stream passing therethrough the turbofan engine, as well as an erosive operational environment.