Abstract: A turbine wheel and bucket assembly comprising a wheel having a peripheral rim machined to include a dovetail shape about the circumference of the rim, interrupted only by a bucket installation slot; and a plurality of buckets installed on the wheel, each bucket having a dovetail portion and blade portion, with the dovetail portion machined to include a complimentary dovetail shape enabling each bucket to be slidably received on the wheel dovetail shape; each bucket having an integral cover at a radial tip of the blade portion, each cover having axially extending surfaces on either side of angled contact surfaces adapted to engage mating contact surfaces of adjacent covers such that the buckets are pretwisted in a first direction. The dovetail shape includes a keyway and a complimentary key is provided on the rim of the wheel, the key receivable within the keyway to prevent rotation of the dovetail portion of the bucket relative to the wheel.

Abstract: Arcuate seal segments have radially directed seal faces forming part of a labyrinth seal in a turbine. The segments are adjustably spaced from the locating flanges of the groove formed on a stationary part of the turbine housing to compensate for any distortion of the groove through use. In a positive pressure, variable clearance labyrinth seal, side seals are disposed between the locating flanges of the groove and the flanges of the seal segments and have surfaces at circumferentially spaced positions which are adjustable to maintain concentricity of the seal faces of the seal segments, notwithstanding the distortion of eccentricity of the groove and its locating flanges. Where the locating flanges of the segments normally engage the locating flanges of the groove, variable clearances are provided between those flanges by the interposition of dowels, plugs or pads such that the seal faces of the segments are maintained concentric, notwithstanding distortion of the locating fits.

Abstract: In a steam turbine rotor wheel and bucket dovetail joint construction wherein the wheel dovetail includes three radially aligned hooks each interconnected by a neck having an upper and lower fillet, an improvement includes redesigned fillet radii which, in a first embodiment, include the upper fillet having a radius greater than the lower fillet radius. In certain embodiments, the upper fillet may have a radius twice that of the lower fillet. In other embodiments, the radii in both the upper and lower fillets have been enlarged.

Abstract: Arcuate seal segments have radially directed seal faces forming part of a labyrinth seal in a turbine. The segments are adjustably spaced from the locating flanges of the groove formed on a stationary part of the turbine housing to compensate for any distortion of the groove through use. In a positive pressure, variable clearance labyrinth seal, side seals are disposed between the locating flanges of the groove and the flanges of the seal segments and have surfaces at circumferentially spaced positions which are adjustable to maintain concentricity of the seal faces of the seal segments, notwithstanding the distortion of eccentricity of the groove and its locating flanges. Where the locating flanges of the segments normally engage the locating flanges of the groove, variable clearances are provided between those flanges by the interposition of dowels, plugs or pads such that the seal faces of the segments are maintained concentric, notwithstanding distortion of the locating fits.