Blade group with pinned root
AssigneeSiemens Westinghouse Power Corporation
InventorAlbert J. Partington
Life of this patent
Estimating the term…
Abstract
A plurality of rotatable turbine blades are formed integral with a shroud and platform and a plurality of arcuate plate root portions which are received by circumferential grooves in a rotor and are fastened to the rotor by three pins extending axially through the root portions and the rotor, the shroud and platform portions having a protrusion on one corner to support the trailing edge of one of the blade portions and a notch in the shroud and the platform on the corner opposite the protrusion whereby the protrusions on one group of blades register with the notch on an adjacent group of blades when the groups of blades are disposed in a circular array on the rotor.
Claims18
A blade group which attaches to a disc disposed on a shaft on an axial flow turbine, said blade group comprising:
- a shroud;
- a platform portion;
- multiple blade portions extending radially outwardly from between said platform portion and said shroud;
- multiple root portions extending radially inwardly from said platform portion, said root portions having root end edges;
- said root portions comprising generally flat spaced-apart arcuate segments disposed normal to the axis of said shaft;
- said disc having circumferential grooves which receive said root portions;
- multiple pins extending axially through said root portions and said disc;
- said platform and said shroud each having a protrusion only on one corner and a notch only on an opposite corner of the same axial side of the blade group so that the protrusions on one blade group fits fit the notches on an adjacent blade group when a plurality of blade groups are disposed in a circular array on the disc, wherein said protrusion on said platform extends in a direction normal to a radial line and normal to the turbine axis beyond the respective root end edges of all of said root portions and has a slanted surface between the root end edges of said root portions and a top surface of said platform;
- and
- a trailing end of one of the blades in each blade group is disposed between the protrusion on the shroud and the protrusion on the platform.
A blade group which attaches to a disc disposed on a shaft of an axial flow turbine, said blade group comprising:
- a shroud;
- a platform portion;
- multiple blade portions extending radially outwardly between said platform portion and said shroud;
- multiple root portions extending radially inwardly from said platform portion, each root portion having root end edges;
- said root portions comprising generally flat space-apart arcuate segments disposed normal to the axis of said shaft, wherein the space between the root portion has a arcuate surface having a radius smaller than the radius of the outer diameter of the disc;
- said disc having circumferential grooves which receive said root portions;
- a plurality of pins extending axially through said root portions and said disc, wherein at least outboard ones of said pins extend through said root portions at positions that are substantially equidistant from the root end edges;
- said platform and said shroud each having a protrusion only on one corner and a notch only on an opposite corner on the same axial side of the blade group so that the protrusions on one blade group fit the notches on an adjacent blade group when a plurality of blade groups are disposed in a circular array on the disc, wherein said protrusion on said platform extends beyond the respective root end edges of all of said root portions in a direction normal to the root end edges of the root portions;
- and
- a trailing end of one of the blades in each blade group is disposed between the protrusion on the shroud and the protrusion on the platform.
Dependencies are inferred from the claim text.