US 8,979,488 B2 · Cast turbine casing and nozzle diaphragm preforms

Abstract

Various turbine component preforms are disclosed having near-net shape features. In one embodiment, a turbine casing preform is disclosed. The turbine casing preform includes an as-cast body comprising a partially cylindrical wall section of a turbine casing, the wall section having an inner surface and an outer surface. The turbine casing preform also includes a circumferentially-extending vane slot formed in the wall section on the inner surface. In another embodiment, a turbine nozzle diaphragm preform is disclosed. The turbine nozzle diaphragm preform includes an as-cast body comprising a partially-cylindrical wall section of a turbine nozzle diaphragm having an inner surface and an outer surface. The turbine nozzle diaphragm preform also includes an as-cast, circumferentially-extending seal member projecting from one of the outer surface or inner surface.

Claims20

Dependent claims

A turbine casing preform, comprising:

an as-cast body comprising a partially cylindrical wall section of a turbine casing, the wall section having an inner surface and an outer surface, the as-cast body comprising a nodular cast iron;
and
an as-cast vane slot formed in the wall section on the inner surface, the inner surface proximate the as-cast vane slot comprising a fine grain size as-cast microstructure having an average graphite nodule count of 100/mm2 or less, the as-cast vane slot having an as-cast slot profile that is configured for removal of the nodular cast iron to a depth sufficient to form a final vane slot having a final slot profile and a microstructure proximate the final vane slot that is substantially the same as the as-cast microstructure.

Dependencies are inferred from the claim text.

Cast turbine casing and nozzle diaphragm preforms

Life of this patent

Cast turbine casing and nozzle diaphragm preforms

Life of this patent

Abstract

Claims20