Gas turbine engine combustor top hat cover attachment system with lugged interlocking backing plate

Patent metadata

Field	Value
Publication number	US-9513011-B2
Application number	US-201414294451-A
Country	US
Kind code	B2
Filing date	Jun 3, 2014
Priority date	Jun 3, 2014
Publication date	Dec 6, 2016
Grant date	Dec 6, 2016

Abstract

Combustor top hat covers are attached to midframe combustor portals with a lugged backing plate that interlocks with mating recesses formed in the corresponding midframe combustor portal. Exemplary embodiments utilize twist lock engagement of backing plate ring lugs under projecting tabs formed over a lug raceway recess in the combustor portal mating surface. The top hat cover is in turn fastened to the combustor portal by fasteners that engage corresponding threaded apertures formed in the backing plate.

First claim

What is claimed is:

1. A gas turbine engine combustor top hat cover attachment system, comprising:
a combustor section midframe defining a combustor portal;
a combustor portal mating surface circumscribing an outwardly exposed periphery of the combustor portal, the mating surface defining an array of projecting tabs that are separated by lug recesses;
a lug raceway defined within the combustor portal mating surface beneath the projecting tabs that is in communication with the lug recesses;
a first array pattern of through hole apertures defined in the combustor portal mating surface that correspond to an array pattern of combustor top hat cover fastener apertures; and
a backing plate having a ring, including a plurality of projecting ring lugs, that is adapted for interlocking engagement with the combustor portal mating surface by insertion of the ring lugs into the lug recesses and rotation of the ring lugs in the lug raceway under the projecting tabs, the backing plate defining a second array pattern of threaded apertures that correspond to an array pattern of top hat cover fastener apertures, the second array of threaded apertures adapted for coaxial alignment with the first array corresponding through hole apertures and capture of top hat cover fasteners.

2. The attachment system of claim 1 , the ring lugs projecting radially outwardly from an outer circumference of the ring and the projecting tabs projecting radially inwardly from the combustor portal mating surface.

3. The attachment system of claim 2 , further comprising the first array pattern of apertures defined in the projecting tabs and the second array pattern of apertures defined in the ring lugs.

4. The attachment system of claim 3 , further comprising the ring or the combustor portal mating surface or both defining a ring seal groove on an outer axial surface thereof, for receipt of a top hat cover static seal.

5. The attachment system of claim 1 , further comprising the ring or the combustor portal mating surface or both defining a ring seal groove on an outer axial surface thereof, for receipt of a top hat cover static seal.

6. The attachment system of claim 1 , further comprising a top hat cover having a third array pattern of apertures corresponding to the first and second array patterns of apertures, the third array pattern of apertures adapted for passage of top hat cover fasteners therethrough and retention of the top hat cover on the combustor section midframe.

7. The attachment system of claim 6 , the ring lugs projecting radially outwardly from an outer circumference of the ring and the projecting tabs projecting radially inwardly from the combustor portal mating surface.

8. The attachment system of claim 7 , further comprising the ring or the combustor portal mating surface or both defining a ring seal groove on an outer axial surface thereof, for receipt of a top hat cover static seal.

9. The attachment system of claim 8 , further comprising a top hat cover static seal in the ring seal groove.

10. The attachment system of claim 6 , further comprising the ring or the combustor portal mating surface or both defining a ring seal groove on an outer axial surface thereof, for receipt of a top hat cover static seal.

11. The attachment system of claim 10 , further comprising a top hat cover static seal in the ring seal groove.

12. A method for attaching a gas turbine engine combustor top hat cover to a combustor section midframe combustor portal, comprising:
providing a combustor section midframe defining a combustor portal with a combustor portal mating surface circumscribing an outwardly exposed periphery of the combustor portal, the mating surface defining an array of projecting tabs that are separated by lug recesses; a lug raceway defined within the combustor portal mating surface beneath the projecting tabs that is in communication with the lug recesses; a first array pattern of through hole apertures defined in the combustor portal mating surface that correspond to an array pattern of combustor top hat cover fastener apertures;
providing a backing plate having a ring, including a plurality of projecting ring lugs, that is adapted for interlocking engagement with the combustor portal mating surface by insertion of the ring lugs into the lug recesses and rotation of the ring lugs in the lug raceway under the projecting tabs, the backing plate defining a second array pattern of threaded apertures that correspond to an array pattern of top hat cover fastener apertures, the second array of threaded apertures adapted for coaxial alignment with the first array corresponding through hole apertures and capture of top hat cover fasteners;
inserting the backing plate into the combustor portal mating surface, so that the ring lugs pass through the lug recesses;
rotating the inserted backing plate so that the lugs are oriented under the projecting tabs;
coaxially aligning the first and second aperture arrays;
providing a top hat cover having a third array pattern of apertures corresponding to the first and second array patterns of apertures;
coaxially aligning the third array pattern of apertures with the first and second aperture arrays; and
passing top hat cover fasteners through the third and second array pattern of apertures and engaging the fasteners with corresponding threaded apertures of the first array pattern of apertures.

13. The method of claim 12 further comprising replacing a backing plate by:
unfastening and retracting the top hat cover fasteners;
removing the top hat cover, exposing the a previously installed first backing plate;
disengaging the first backing plate from the combustor portal mating surface by twisting the cover plate so that the ring lugs are within the lug recesses and axially retracting the first backing plate; and
engaging a second backing plate into the combustor portal mating surface by inserting and rotating said second backing plate.

14. The method of claim 13 , the second backing plate comprising a repaired threaded aperture in the second array pattern of apertures.

Assignees

• Siemens Energy Inc

Inventors

• Carlson Andrew

Classifications

• Y10T29/49734

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• Y10T29/49325

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• F23R2900/00017

  Assembling combustion chamber liners or subparts · CPC title

• F23R3/283 Primary

  Attaching or cooling of fuel injecting means including supports for fuel injectors, stems, or lances · CPC title