Liquid cooled turbine bucket with dovetailed attachment

Claim 2

Turbine bucket construction comprising in combination: a. integrally formed airfoil-shaped core, platform and root portions, said root portion having a dovetailed configuration, b. a first group of cooling grooves recessed into the upper surface of said platform portion, c. a second group of cooling grooves recessed into the pressure and suction faces of the airfoil-shaped core, each of the cooling grooves in said first group being connected to a separate cooling groove in said second group, d. skin material disposed over said upper surface of said platform portion and over said pressure and suction faces thereby covering said first and second groups of cooling grooves, e. a pair of longitudinally-extending recesses formed in the underside of said platform portion one of said recesses extending along each side of, in the same direction as, and adjacent to said dovetailed configuration, a pair of longitudinally-extending gutters formed in the underside of said platform portion, one of said gutters extending parallel to and adjacent each of said recesses, f. a pair of longitudinally-extending projections formed along the underside of said platform portion, each of said projections separating one recess and one gutter, each of said projections having a crest, said crest being arcuate in crosssection and presenting a convex cylindrical surface, the elements of the cylindrical surfaces of both crests being parallel to the elements of the cylindrical convex ridges of said dovetailed configuration and g. a plurality of holes passing through said platform portion placing said first group of cooling grooves in flow communication with the underside of said platform portion adjacent each of said projections on the side thereof away from the recess adjacent thereto.

Claim 3

Turbine bucket construction comprising in combination: a. integrally formed airfoil-shaped core, platform and root portions, said root portion having a dovetailed configuration, b. a first group of cooling grooves recessed into the upper surface of said platform portion, c. a second group of cooling grooves recessed into the pressure and suction faces of the airfoil-shaped core, each of the cooling grooves in said first group being connected to a separate cooling groove in said second group, d. skin material disposed over said upper surface of said platform portion and over said pressure and suction faces thereby covering said first and second groups of cooling grooves, e. a pair of longitudinally-extending recesses formed in the underside of said platform portion one of said recesses extending along each side of, in the same direction as, and adjacent to said dovetailed configuration, a pair of longitudinally-extending gutters formed in the underside of said platform portion, one of said gutters extending parallel to and adjacent each of said recesses, f. a pair of longitudinally-extending projections formed along the underside of said platform portion, each of said projections separating one recess and one gutter, each of said projections having a crest, said crest being arcuate in cross-section and presenting a convex cylindrical surface, the elements of the cylindrical surfaces of both crests being parallel to the elements of the cylindrical convex ridges of said dovetailed configuration and g. a plurality of holes passing through said platform portion placing said first group of cooling grooves in flow communication with the underside of said platform portion adjacent each of said projections on the side thereof away from the recess adjacent thereto.

Claim 4

Turbine bucket construction comprising in combination: a. integrally formed airfoil-shaped core, platform and root portions, said root portion having a dovetailed configuration, b. a first group of cooling grooves recessed into the upper surface of said platform portion, c. a second group of cooling grooves recessed into the pressure and suction faces of the airfoil-shaped core, each of the cooling grooves in said first group being connected to a separate cooling groove in said second group, d. skin material disposed over said upper surface of said platform portion and over said pressure and suction faces thereby covering said first and second groups of cooling grooves, e. a pair of longitudinally-extending recesses formed in the underside of said platform portion one of said recesses extending along each side of, in the same direction as, and adjacent to said dovetailed configuration, a pair of longitudinally-extending gutters formed in the underside of said platform portion, one of said gutters extending parallel to and adjacent each of said recesses, f. a pair of longitudinally-extending projections formed along the underside of said platform portion, each of said projections separating one recess and one gutter, each of said projections having a crest, said crest being arcuate in cross-section and presenting a convex cylindrical surface, the elements of the cylindrical surfaces of both crests being parallel to the elements of the cylindrical convex ridges of said dovetailed configuration and g. a plurality of holes passing through said platform portion placing said first group of cooling grooves in flow communication with the underside of said platform portion adjacent each of said projections on the side thereof away from the recess adjacent thereto.

Claim 5

The turbine bucket as recited in claim 1 wherein the crest of the longitudinally extending projection is in the form of an arc of a circle in cross-section.

Claim 6

The turbine bucket as recited in claim 1 wherein the far ends of each of the recesses formed in the underside of the platform portion are closed off by a pair of plate-like members.

Claim 7

The turbine bucket as recited in claim 1 wherein the pair of recesses and the pair of projections are located between the pair of gutters.

Claim 8

The turbine bucket as recited in claim 1 wherein each groove of the second group of cooling grooves terminates in one of two interconnected manifolds located near the tip of said bucket.

Claim 9

The turbine bucket as recited in claim 6 wherein the pair of recesses and the pair of projections are located between the pair of gutters.

Claim 10

The improvement recited in claim 6 wherein the far ends of each of the recesses formed in the underside of the platform portion are closed off by a pair of plate-like members.

Claim 11

The improvement recited in claim 6 wherein in a given bucket the holes passing through the platform portion to the underside thereof are divided into two sets, one set in flow communication with cooling grooves on the pressure side of said bucket and the second set in flow communication with cooling grooves on the suction side of said bucket.