Transition piece external frame support

• US 5,761,898 A
• Filed: 08/01/1996
• Issued: 06/09/1998
• Est. Priority Date: 12/20/1994
• Status: Expired due to Fees

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Barnes, John Eugene, Anderson, Rodger Orval, Steber, Charles Evan
• Primary Examiner(s): Thorpe, Timothy
• Assistant Examiner(s): KIM, TAE JUN
• Application Number:
  US08/690,954
• Time in Patent Office: 677 Days
• Field of Search: 60/39.31, 60/39.32, 60/39.75, 60/39.37, 60/722, 60/747, 60/752, 415/182.1
• US Class Current: 60/799
• CPC Class Codes: F01D 9/023 Transition ducts between combustor cans and first stage of the turbine in gas-turbine engines; their cooling or sealings
• CPC Class Codes: F23R 3/60 Support structures; Attaching or mounting means

Abstract

A transition piece for connection between a gas turbine combustor and a stage of the gas turbine, the transition piece being generally tubular and having an upstream end for connection to the gas turbine combustor and a downstream or aft end for connection to the turbine stage, the aft end defined by radially inner and outer sides, and wherein the aft end is formed with a peripheral rib extending about the end and wherein at least one of the radially inner and outer sides has an external frame support secured thereto and extending substantially completely between the opposite sides which provides resistance to external pressure at the aft end while permitting the transition piece to expand thermally.

Claims

1. A tubular transition piece for connection between a gas turbine combustor and a stage of the gas turbine, the transition piece having an upstream end for connection to the gas turbine combustor and a downstream or aft end for connection to the turbine stage, the aft end having an opening defined by radially inner and outer walls and a pair of opposite side walls, and wherein the aft end is formed with a peripheral rib extending about the end opening and wherein at least one of said radially inner and outer walls has an external structural frame member fixedly secured thereto only at a lateral mid-point of said one of said radially inner and outer walls and extending substantially completely between said opposite side walls, said exterior structural frame member providing resistance to external pressure at said aft end while permitting said transition piece to expand thermally.

2. The transition piece according to claim 1 wherein said frame is external to said transition piece and extends completely about the periphery of the aft end.

3. The transition piece of claim 1 wherein said external frame is rigidly fixed to said peripheral rib only at a mid-span location of said radially outer side, thereby permitting the transition piece to expand thermally with respect to said external frame.

4. The transition piece according to claim 1 wherein said frame is integral with said aft end and includes a first support rod attached thereto and extending along said radially inner side and a second support rod attached thereto and extending along said radially outer side.

5. The transition piece of claim 3 wherein said first and second support rods are prestressed to exert outwardly directed forces on said transition piece.

6. The transition piece of claim 2 wherein each of said first and second support rods is rigidly clamped to the respective radially inner and outer sides.

7. The transition piece of claim 3 wherein each support rod is slidably supported at opposite ends thereof in saddles affixed to the respective radially inner and outer sides, thereby permitting the transition piece to expand thermally.

8. The transition piece according to claim 1 wherein said peripheral rib is integral with said aft end, and wherein said external structural frame member comprises a prestressed support rod affixed to substantially a lateral mid-point of said radially inner wall, and further wherein said support rod is slidably supported at remote ends thereof.

9. The transition piece of claim 4 wherein said radially outer side is adapted to be supported by a retaining ring on the stage of the gas turbine.

10. The transition piece of claim 9 wherein said radially outer side includes a first axially oriented pin adapted to be engaged by a complementary hole in said retaining ring at a mid-span location, and wherein said radially outer side also includes second and third axially oriented pins at remote ends thereof which are adapted to be engaged in elongated slots in said retaining ring.

11. A transition piece for connection between a combustor and a stage of a gas turbine, said transition piece having an upstream end adapted for connection to the combustor and a downstream end adapted for connection to the stage of the gas turbine;

said downstream end having an opening defined by radially inner and outer walls and opposite side walls, said opening surrounded by an integral frame including a peripheral rib extending at least about said radially inner and outer walls of said integral frame;

an external structural frame member connected to one of said radially inner and outer walls and extending substantially completely between said opposite side walls, said external structural frame member fixedly secured only at one location along a length dimension of said external frame member to thereby provide structural support to said transition piece against external pressure but to permit relative movement between said transition piece and said external structural frame member due to thermal expansion of said transition piece.

12. The transition piece of claim 11 wherein said external structural frame member is secured to said radially inner wall of said integral frame.

13. The transition piece of claim 12 wherein said external structural frame member is secured substantially at a mid-point of said radially inner wall.

14. The transition piece of claim 13 wherein said radially inner wall is formed with depending projections, and wherein said external structural frame member is formed with grooves at opposite ends thereof arranged to slidably receive said projections.

15. The transition piece of claim 14 wherein said integral frame is formed with a mounting flange at said mid-point and said external structural frame member is formed with a recess receiving said mounting flange.