GAS TURBINE WITH WELDED COMBUSTOR LINERS

• US 20100205973A1
• Filed: 03/16/2010
• Published: 08/19/2010
• Est. Priority Date: 09/24/2007
• Status: Active Grant

• Current Assignee: General Electric Technology GmbH (GE Aerospace)
• Original Assignee: Alstom Technology Ltd. (Alstom SA)
• Inventors: Markovic, Alen, Schneider, Lothar, Tschuor, Remigi, Hähnle, Hartmut
• Granted Patent: US 8,516,823 B2
• Time in Patent Office: Days
• US Class Current: 60/752
• CPC Class Codes: B23P 2700/13 Parts of turbine combustion chambers
• CPC Class Codes: B23P 6/002 Repairing turbine components, e.g. moving or stationary blades, rotors, B23P6/045 takes precedence
• CPC Class Codes: F23R 2900/00017 Assembling combustion chamber liners or subparts
• CPC Class Codes: F23R 2900/00019 Repairing or maintaining combustion chamber liners or subparts
• CPC Class Codes: F23R 2900/03042 Film cooled combustion chamber walls or domes
• CPC Class Codes: F23R 2900/03044 Impingement cooled combustion chamber walls or subassemblies
• CPC Class Codes: F23R 3/002 Wall structures F23R3/02 and F23R3/007 take precedence
• CPC Class Codes: Y10T 29/49318 Repairing or disassembling

Abstract

In order to provide an annular combustion chamber (3) which can be heated without thermal distortion, expands without distortion, and is reliably closed, and for repairs can be opened and permanently closed again and can be reconditioned, the inner and/or outer shell (8, 7) of an annular combustion chamber (3) is produced from a rotationally symmetrical sheet metal. For assembly, the shells are cut open along a split line (16), and the lower half of the inner and of the outer shell (8, 7) is introduced into the lower casing half of a gas turbine. After the insertion of the rotor, the two upper shell halves can likewise be inserted and be connected to the lower halves by welding. In order to improve the service life of the split line weld seam (21), film cooling of the weld seam is routed by an indentation. This may be implemented, for example, by welded-in split line elements (15) which are also suitable for retrofitting.

Claims

1. A gas turbine comprising:

at least one annular combustion chamber comprising an annular inner shell and an annular outer shell each having a split line which splits each shell into an upper half shell and a lower half shell;

wherein the inner shell, the outer shell, or both shells is closed in the split line by at least one split line weld seam; and

cooling holes configured and arranged to film-cool at least part of the at least one split line weld seam.

2. A gas turbine as claimed in claim 1, wherein at least one of the inner and outer shells comprises, in the region of the split line weld seam, an indentation pointing away from the hot gas side of the at least one annular combustion chamber, the indentation configured and arranged to guide a cooling air film along the split line weld seam.

3. A gas turbine as claimed in claim 2, wherein the indentation is oriented parallel to the main flow of the at least one annular combustion chamber.

4. A gas turbine as claimed in claim 1, further comprising a heat protection layer on the hot gas side of at least one of the inner shell and the outer shell.

5. A gas turbine as claimed in claim 1, wherein the cooling side of the at least one annular combustion chamber further comprises turbulence ribs in the region of the split line weld seam configured and arranged to cool the split line weld seam.

6. A gas turbine as claimed in claim 1, further comprising:

impingement cooling holes configured and arranged to cool the at least one split line weld seam.

7. A gas turbine as claimed in claim 1, further comprising:

a split line element having an indentation which points away from the hot gas side of the at least one annular combustion chamber and which guides cooling air film along the split line weld seam, the split line element being welded into at least one of the inner shell and the outer shell in the region of the split line.

8. A gas turbine as claimed in claim 7, wherein the split line element has a wall thickness which is different from that of said at least one of the inner shell and outer shell.

9. A gas turbine as claimed in claim 7, wherein the indentation has a dovetail shape.

10. A method for the installation or exchange of at least one of an inner shell and an outer shell of a gas turbine, the gas turbine having at least one annular combustion chamber which is formed from an annular inner shell and an annular outer shell, the annular inner shell, the annular outer shell, or both having a split line which splits the shell into an upper half shell and a lower half shell, the method comprising:

cutting open at least one of the inner shell and the outer shell at the split line;

installing said at least one of the inner shell and the outer shell in the gas turbine, or exchanging a portion of a used shell with said least one of the inner shell and the outer shell in the gas turbine; and

closing said at least one of the inner shell and the outer shell at the split line with an at least partially film-cooled split line weld seam.

11. The method as claimed in claim 10, further comprising, before said installing or exchanging:

cutting out an elongate sheet metal strip from the annular inner shell, from the annular outer shell, or from both to form at least one gap;

fitting at least one split line element into the at least one gap; and

welding in the at least one split line element in the at least one gap.

12. The method as claimed in claim 11, wherein the at least one split line element is oversized, and further comprising:

cutting to size the at least one split line element.

13. The method as claimed in claim 11, further comprising, during each exchanging of a split line element, cutting away existing weld seams which connect the split line element to the inner shell, to the outer shell, or to both, so that, during each exchanging, the width of the elongate cut-out sheet metal strip becomes greater and, during each exchanging, less residual material is cut off from the oversized split line element.

14. The method as claimed in claim 11, further comprising:

applying a heat protection layer to the hot gas side of the weld seams which connect the split line element to the inner shell, to the outer shell, or to both.

15. The method as claimed in claim 10, wherein installing comprises installing the split line element during a repair or reconditioning of the at least one inner shell and outer shell.