Abstract: The present disclosure is directed to a method for scaling an airfoil for placement in a turbomachine. The method disclosed herein includes radially scaling a master airfoil to form a scaled airfoil. The method may also include tuning the scaled airfoil. For example, tuning the scaled airfoil may include axially scaling. The scaled airfoil generally has similar characteristics to the master airfoil.

Abstract: A method of engineering a turbomachine airfoil may include providing a master airfoil configuration having a preset outer and inner radius relative to an axis of rotation thereof. The master airfoil configuration may be radially scaled to a custom-sized turbomachine airfoil having an outer radius different than the preset outer radius of the master airfoil configuration, and/or an inner radius different than the preset inner radius of the master airfoil configuration. Tuning a frequency of the custom-sized turbomachine airfoil by changing a parameter of at least one of a part span shroud and a tip shroud may then be performed. Axial scaling may also be performed. The custom-sized turbomachine airfoil may be employed in the turbomachine without performing wheel box testing, and may exhibit substantially similar operational characteristics as the master airfoil configuration.

Abstract: Swivel dovetail connections, such as a tangential entry, straight axial entry or curved axial entry dovetails, for connecting a blade and a rotor wheel in a turbomachine are disclosed. A modified shape of dovetail contact surfaces creates a swivel dovetail connection between blades and rotor wheels, and allows limited motion of blades relative to wheels, while still maintaining the structural connection between blades and wheels. The swivel dovetail connection is achieved by providing concave or convex dovetail contact surfaces between a rotor wheel and a blade such that the contact surfaces lie along a common substantially toroidal arc, an axially extending, substantially cylindrical arc, or a substantially frusto-conical arc.

Abstract: Swivel dovetail connections, such as a tangential entry, straight axial entry or curved axial entry dovetails, for connecting a blade and a rotor wheel in a turbomachine are disclosed. A modified shape of dovetail contact surfaces creates a swivel dovetail connection between blades and rotor wheels, and allows limited motion of blades relative to wheels, while still maintaining the structural connection between blades and wheels. The swivel dovetail connection is achieved by providing concave or convex dovetail contact surfaces between a rotor wheel and a blade such that the contact surfaces lie along a common substantially toroidal arc, an axially extending, substantially cylindrical arc, or a substantially frusto-conical arc.

Abstract: A blade mountable to a disc comprises a blade platform and a blade root extending from the blade platform. The blade root comprises first, second, and third hooks and first, second and third necks. Each hook comprises a contact surface and a non-contact surface, and an angle between each contact surface and each non-contact surface is optimized to reduce local and average stresses.

Abstract: A rotating blade for a steam turbine includes a root section and an airfoil section contiguous with the root section. The airfoil section is shaped to optimize aerodynamic performance while providing optimized flow distribution and minimal centrifugal and bending stresses. The blade also includes a tip section continuous with the airfoil section, and a cover formed as part of the tip section. The cover defines a radial seal that serves to minimize tip losses. The rotating blade is capable of running at operating speeds between 5626 and 11250 rotations per minute.

Abstract: A rotating blade for a steam turbine includes a root section and an airfoil section contiguous with the root section. The airfoil section is shaped to optimize aerodynamic performance while providing optimized flow distribution and minimal centrifugal and bending stresses. The blade also includes a tip section continuous with the airfoil section, and a cover formed as part of the tip section. The cover defines a radial seal that serves to minimize tip losses. The rotating blade is capable of running at operating speeds between 5626 and 11250 rotations per minute.

Abstract: A bucket for use in the low-pressure section of a steam turbine engine is provided. The bucket has a vane length of at least about 45 inches. The bucket is comprised of a dovetail section disposed near an inner radial position of the bucket, a tip shroud disposed near an outer radial position of the bucket and a part span shroud disposed at an intermediate radial position. The intermediate radial position is located between the inner and outer radial positions. The bucket is comprised of a titanium-based alloy having between about 2% and about 6.25% by weight aluminum, up to about 3.5% vanadium, up to about 2.25% tin, up to about 2.25% zirconium, between about 1.75% and about 5.0% molybdenum, up to about 2.25% chromium, up to about 0.7% silicon and up to about 2.3% iron, with the balance being titanium.

Abstract: A blade mountable to a disc comprises a blade platform and a blade root extending from the blade platform. The blade root comprises first, second, and third hooks and first, second and third necks. Each hook comprises a contact surface and a non-contact surface, and an angle between each contact surface and each non-contact surface is optimized to reduce local and average stresses.

Abstract: A bucket for use on a steam turbine rotor wheel, the bucket comprising a shank portion and an airfoil portion, the airfoil portion having a radially outer tip with a tip cover adapted to be engaged, in use, by a similar tip cover on an adjacent bucket, wherein a radial step is formed in the tip cover and the airfoil portion along a leading edge of the airfoil portion.

Abstract: A bucket for use on a steam turbine rotor wheel, the bucket comprising a shank portion and an airfoil portion, the airfoil portion having a radially outer tip with a tip cover adapted to be engaged, in use, by a similar tip cover on an adjacent bucket, wherein a radial step is formed in the tip cover and the airfoil portion along a leading edge of the airfoil portion.

Abstract: A method of modifying a rotor blade, and a rotor blade are provided. The rotor blade is for a steam turbine and it is modified to facilitate altering a natural vibratory frequency of the rotor blade, the rotor blade includes a leading edge, a trailing edge, a first sidewall, and a second sidewall, wherein the first and second sidewalls are connected axially at the leading and trailing edges, and the sidewalls extending radially between a rotor blade root to a rotor blade tip. The method includes determining a vibratory resonance condition of the rotor blade and forming a blade extension between the rotor blade root and the rotor blade tip that alters the determined resonance condition.

Abstract: A method of modifying a rotor blade, and a rotor blade are provided. The rotor blade is for a steam turbine and it is modified to facilitate altering a natural vibratory frequency of the rotor blade, the rotor blade includes a leading edge, a trailing edge, a first sidewall, and a second sidewall, wherein the first and second sidewalls are connected axially at the leading and trailing edges, and the sidewalls extending radially between a rotor blade root to a rotor blade tip. The method includes determining a vibratory resonance condition of the rotor blade and forming a blade extension between the rotor blade root and the rotor blade tip that alters the determined resonance condition.