Gas turbine component

Abstract

A gas turbine component for a gas turbine is provided. The gas turbine component has a shell portion having an abradable portion (2) to allow rotor blade ends (1) of a rotor blade array of the gas turbine to rub into the same. The abradable portion adjoins a neighboring portion (3) of the shell portion axially at both sides and is additively manufactured together therewith.

Claims

1. A gas turbine component for a gas turbine, the gas turbine component comprising: a shell portion, the shell portion having an abradable portion to allow rotor blade ends of a rotor blade array of the gas turbine to rub into the abradable portion, the abradable portion having two axial sides spaced axially, the abradable portion adjoining a neighboring portion of the shell portion axially at both axial sides, the abradable portion and the neighboring portion being additively manufactured together by locally solidifying both the abradabale portion and the neighboring portion material together in each layer of a layer-by-layer structure, the abradable portion having at least one of the following: a lower surface hardness than the neighboring portion; a lower density than the neighboring portion; the abradable portion being porous, the abradable portion having a larger maximum, minimum or average pore size than the neighboring portion; and the abradable portion and the neighboring portion containing different materials.

2. The gas turbine component as recited in claim 1 wherein the abradable portion has the lower surface hardness than the neighboring portion.

3. The gas turbine component as recited in claim 1 wherein the abradable portion has the lower density than the neighboring portion.

4. The gas turbine component as recited in claim 1 wherein the abradable portion is porous, the abradable portion having the larger maximum, minimum or average pore size than the neighboring portion.

5. The gas turbine as recited in claim 4 wherein the neighboring portion is pore-free.

6. The gas turbine component as recited in claim 1 wherein the abradable portion and the neighboring portion contain the different materials.

7. The gas turbine component as recited in claim 1 wherein a radial offset between surfaces of the abradable portion and the axially adjacent neighboring portion facing the rotor blade array is no greater than 5 mm.

8. The gas turbine component as recited in claim 1 wherein a radial wall thickness of the abradable portion is at least 1 mm or no greater than 20 mm.

9. The gas turbine component as recited in claim 1 wherein the neighboring portion has axial ribs extending axially into the abradable portion.

10. The gas turbine component as recited in claim 9 wherein the neighboring portion has axial ribs extending axially through the abradable portion, the abradable portion being segmented by the axial ribs.

11. The gas turbine component as recited in claim 1 wherein the shell portion is of single-piece or multi-piece construction.

12. A gas turbine comprising: a casing part having a rotor blade array rotatably disposed therein; and the gas turbine component as recited in claim 1, the shell portion housing the rotor blade array and being connected to or formed integrally with the casing part.

13. An aircraft gas turbine comprising the gas turbine as recited in claim 12.

14. The gas turbine as recited in claim 12 wherein the abradable portion projects axially beyond the rotor blade ends of the rotor blade array on one or both sides by at least 1 mm or by no more than 10 mm.

15. A method for manufacturing the gas turbine component as recited in claim 1 comprising: additively manufacturing the abradable portion together with the neighboring portion.

16. A method for repairing the gas turbine component as recited in claim 1 comprising: removing the rubbed-in abradable portion to define a recess; and mounting a separately manufactured abradable liner in the recess.

17. The method as recited in claim 16 wherein the removing includes machining.

18. The method as recited in claim 16 wherein the abradable portion and the neighboring portion are additively manufactured optically.

19. The method as recited in claim 16 wherein the material is a powder.

20. The method as recited in claim 16 wherein the material includes different materials for the abradable portion and the neighboring portion.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further advantageous refinements of the present invention will be apparent from the dependent claims and the following description of preferred embodiments. To this end, the drawings show, partly in schematic form, in:

(2) FIG. 1: a portion of a shell portion of a gas turbine component of a gas turbine according to an embodiment of the present invention in a cross section taken along line I-I of FIG. 2; and

(3) FIG. 2: a developed view of a portion of the shell portion.

(4) FIG. 3: shows a flowchart of a method for manufacturing the gas turbine component by additively manufacturing the abradable portion together with the neighboring portion.

(5) FIG. 4: shows flowchart of a method for repairing the gas turbine component by removing the rubbed-in abradable portion to define a recess; and mounting a separately manufactured abradable liner in the recess.

DETAILED DESCRIPTION

(6) FIG. 2 shows in a developed view a portion of a shell portion of a gas turbine component of a gas turbine according to an embodiment of the present invention, and FIG. 1 shows a cross section taken along line I-I of FIG. 2.

(7) The shell portion houses a rotor blade array of the gas turbine, of which FIG. 1 shows a rotor blade end 1 having sealing fins 1.1 extending radially toward the shell portion.

(8) The gas turbine component may in particular be a seal carrier or casing part of the gas turbine.

(9) The shell portion has an abradable portion 2 to allow rotor blade ends 1 of the rotor blade array to rub into the same, the abradable portion adjoining a neighboring portion 3 of the shell portion axially at both sides (to the left and right in FIGS. 1, 2) and being additively manufactured together therewith.

(10) Abradable portion 2 is intended to exhibit a rubbed-in state during normal operation, and has a lower surface hardness and a lower density than neighboring portion 3.

(11) To this end, abradable portion 2 is additively manufactured so as to be porous or sponge-like, together with solid neighboring portion 3. Additionally or alternatively, abradable portion 2 and neighboring portion 3 are additively manufactured together, as shown in step 101 of FIG. 3, but from different materials, by placing different materials in different regions layer-by-layer and locally solidifying the materials, thereby bonding them to an underlying layer

(12) The surfaces 2.1, 3.1 of the abradable portion and the neighboring portion that face the rotor blade array are flush with each other, so that a radial offset therebetween is about 0 mm.

(13) A radial wall thickness t of abradable portion 2 away from its surface 2.1 that faces the rotor blade array is between 5 mm and 10 mm.

(14) Neighboring portion 3 has a plurality of axial ribs 3.2 which are equidistantly distributed in the circumferential direction (vertically in FIG. 2) and extend axially (horizontally in FIGS. 1, 2) through abradable portion 2, which is segmented by axial ribs 3.2. In addition, neighboring portion 3 adjoins abradable portion 2 also radially (vertically in FIG. 1) on the outside, as can be seen in FIG. 1.

(15) Abradable portion 2 projects axially beyond rotor blade ends 1 of the rotor blade array on both sides by a length s between 2 mm and 5 mm.

(16) In order to effect a repair, rubbed-in abradable portion 2 is initially removed by machining as shown in step 201 of FIG. 4, and a separately manufactured abradable liner is mounted in the recess so produced as shown in step 202 of FIG. 4.

(17) Although the above is a description of exemplary embodiments, it should be noted that many modifications are possible. It should also be appreciated that the exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration in any way. Rather, the foregoing detailed description provides those skilled in the art with a convenient road map for implementing at least one exemplary embodiment, it being understood that various changes may be made in the function and arrangement of elements described without departing from the scope of protection set forth in the appended claims and their equivalent combinations of features.

LIST OF REFERENCE NUMERALS

(18) 1 rotor blade end (rotor blade array) 2 abradable portion 2.1 surface 3 neighboring portion 3.1 surface 3.2 axial rib s axial length t wall thickness