Turbine engine shroud assembly including axially floating shroud segment

• US 6,884,026 B2
• Filed: 09/30/2002
• Issued: 04/26/2005
• Est. Priority Date: 09/30/2002
• Status: Expired due to Term

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Noe, Mark Eugene, Glynn, Christopher Charles, Darkins, Toby George Jr., Alford, Mary Ellen
• Primary Examiner(s): Trieu, Thai-Ba
• Application Number:
  US10/260,478
• Publication Number:
  US 20040062639A1
• Time in Patent Office: 939 Days
• Field of Search: 415/173.1, 415/173.3, 415/134, 415/200, 415/113, 415/136, 415/138, 415/139, 415/208.3, 415/173.2, 415/209.3
• US Class Current: 415/173.1
• CPC Class Codes: F01D 11/08 for sealing space between rotor blade tips and stator specially-shaped blade tips therefor F01D5/20
• CPC Class Codes: F02C 7/20 Mounting or supporting of plant; Accommodating heat expansion or creep
• CPC Class Codes: F05D 2230/642 using maintaining alignment while permitting differential dilatation
• CPC Class Codes: F05D 2240/11 Shroud seal segments
• CPC Class Codes: F05D 2250/41 with one degree of freedom
• CPC Class Codes: F05D 2300/603 Composites; e.g. fibre-reinforced

Abstract

At least one shroud segment, floating axially independently of adjacent turbine engine shroud assembly members, includes a segment body comprising a radially outer surface and a radially outwardly projecting segment support that includes an axial support wall surface therein. The assembly includes a shroud hanger in axial juxtaposition with the segment support, and at least one axial support projection from the shroud hanger into the segment support at the support wall surface. The support projection supports the shroud segment releasably at the support wall surface sufficiently to enable relative axial movement of the shroud segment on the support projection independently of the shroud hanger and adjacent engine members.

Claims

1. A turbine engine shroud segment for assembly circumferentially about an axial flow engine axis, separate and spaced apart from any blading member, the shroud segment comprising a shroud segment body including a radially inner surface arcuate at least circumferentially, a radially outer surface, and at least one shroud segment support integral with the shroud segment body for carrying the shroud segment body, the segment support projecting generally radially outwardly from the shroud segment body radially outer surface, wherein:

the shroud segment is separate and spaced apart from any blading member;

the radially inner surface defines a part of a turbine engine flowpath boundary over rotating blading members; and

,

the shroud segment support includes therein a support wall surface extending generally axially into and at least partially through the segment support.

2. The shroud segment of claim 1 in which the segment support comprises at least one rib integral with and disposed circumferentially along the shroud segment body radially outer surface.

3. The shroud segment of claim 2 made of a low ductility material having a low tensile ductility, measured at room temperature to be no greater than about 1%.

4. The shroud segment of claim 3 in which the low ductility material is a ceramic matrix composite material.

5. The shroud segment of claim 2 including a plurality of axially spaced apart support ribs each including a radially arcuate wall surface aligned axially with an arcuate wall surface of a spaced apart support rib.

6. The shroud segment of claim 2 including a plurality of axially spaced apart support ribs;

at least a first support rib comprising a plurality of spaced apart support rib segments aligned circumferentially to define the support rib,

the support rib segments being spaced circumferentially on the shroud segment body radially outer surface.

7. The shroud segment of claim 6 in which the support rib segments are spaced apart circumferentially on the shroud segment body radially outer surface sufficiently to expose therebetween a portion of the shroud segment body radially outer surface.

8. The shroud segment of claim 6 in which:

the spaced apart support rib segments of the first support rib are hook shaped rib segments each including a radially inner and arcuate support wall surface extending generally axially through the rib segment;

juxtaposed circumferentially spaced apart hook shaped rib segments facing circumferentially opposite one to the other exposing therebetween a portion of the shroud segment body radially outer surface.

9. The shroud segment of claim 8 which includes a second support rib axially spaced apart on shroud segment body radially outer surface aft of the first support rib;

the second support rib comprising a generally arch shaped rib segment extending circumferentially along shroud segment body radially outer surface;

the arcuate support surface of the second support rib segment defining a generally axial passage through the second support rib segment.

10. The shroud segment of claim 9 in which:

the first support rib consists of a pair of the first support hook shaped rib segments; and

,

the second support rib consists of one arch shaped segment axially aft on the shroud segment body radially outer surface of the first support rib and positioned generally axially aft and circumferentially between the pair of first support rib segments to define a triangle between the arcuate support wall surfaces of the first and second support rib segments.

11. The shroud segment of claim 1 in which the support wall surface defines at least one axial passage through the support rib.

12. A turbine engine shroud assembly comprising at least one shroud segment floating axially independently of other engine members disposed in adjacent juxtaposition with the shroud segment in which:

the segment includes therein a shroud segment support wall surface extending generally axially into and at least partially through the shroud;

the shroud assembly includes a shroud hanger disposed in axial juxtaposition with the shroud segment, the shroud hanger including at least one support projection secured with the shroud hanger and extending generally axially from the shroud hanger into the shroud segment at the shroud segment support wall surface, the projection supporting the shroud segment releasably at the shroud segment support wall surface within the shroud segment, the shroud segment being movable axially on the projection independently of the shroud hanger and other engine members in adjacent juxtaposition with the shroud segment.

13. The turbine engine shroud assembly of claim 12 in which:

the shroud segment comprises a shroud segment body including a radially inner surface arcuate at least circumferentially, a radially outer surface, and at least one shroud segment support secured with the shroud segment body for carrying the shroud segment body, the segment support projecting generally radially outwardly from the shroud segment body radially outer surface, the shroud segment support including therein the shroud segment support wall surface extending generally axially into and at least partially through the segment support;

the shroud hanger being disposed in axial juxtaposition with the shroud segment support; and

;

at least one support projection pin extending generally axially from the shroud hanger into the shroud segment support at the shroud segment support wall surface;

the support pin being secured with the shroud hanger and supporting the shroud segment releasably at the support wall surface within the shroud segment support across a clearance sufficient to enable relative axial movement of the shroud segment on the support pin, independently of the shroud hanger, responsive to generally axial pressure applied to the shroud segment during operation of the turbine engine.

14. The shroud assembly of claim 13 in which:

the shroud assembly includes a plurality of shroud segments disposed in circumferential juxtaposition;

the shroud segment support comprises at least one shroud segment support rib integral with and disposed circumferentially along the shroud segment body radially outer surface;

the shroud hanger comprises at least one hanger rib disposed in axial juxtaposition with the shroud segment support rib.

15. The shroud assembly of claim 14 in which the shroud segment support wall surface extends axially through the support rib to define therethrough an axial passage.

16. The shroud assembly of claim 14 in which:

the shroud segment support includes a plurality of axially spaced apart shroud segment support ribs each including a radially arcuate wall surface extending axially through the support rib to define therethrough an axial passage aligned axially with an axial passage of a spaced apart support rib; and

,

a support pin held by the hanger is disposed through each of the aligned passages through the shroud segment support ribs.

17. The shroud assembly of claim 14 in which:

the shroud segment support includes a plurality of axially spaced apart support ribs;

at least a first support rib comprising a plurality of spaced apart support rib segments aligned circumferentially to define the support rib;

the support rib segments being spaced apart circumferentially on the shroud segment body radially outer surface;

each rib segment including a support rib segment wall surface extending axially through the rib segment; and

,

a support pin held by the hanger disposed in juxtaposition with each support rib segment wall surface.

18. The shroud assembly of claim 17 in which the support rib segments are spaced apart circumferentially on the shroud segment body radially outer surface sufficiently to expose therebetween a portion of the shroud segment body radially outer surface.

19. The shroud assembly of claim 17 in which:

the shroud segment is made of a low ductility material having a low tensile ductility, measured at room temperature to be no greater than about 1%;

the shroud segment support wall surface extending axially into the shroud segment support rib is arcuate radially to define a shroud segment arcuate support surface;

the at least one support pin comprises an arcuate outer surface extending generally axially from the hanger rib into the shroud segment support rib at the shroud segment arcuate support surface;

the clearance being sufficient to enable the relative axial movement as well as relative thermal expansion and contraction of the support pin and the segment support rib between the support segment arcuate support surface and the support pin arcuate outer surface;

the spaced apart support rib segments of the first support rib being hook shaped rib segments each including a radially inner and arcuate support wall surface extending generally axially through the rib segment;

juxtaposed circumferentially spaced apart hook shaped rib segments facing circumferentially opposite one to the other exposing therebetween a portion of the shroud segment body radially outer surface.

20. The shroud assembly of claim 19 in which:

the shroud segment includes a second support rib spaced apart on shroud segment body radially outer surface axially aft of the first support rib;

the second support rib comprising a generally arch shaped rib segment extending circumferentially along shroud segment body radially outer surface;

the arcuate support surface of the second support rib segment defining a generally axial passage through the second support rib segment.

21. The shroud assembly of claim 20 in which:

the first support rib consists of a pair of the first support hook shaped rib segments, each including axially therethrough the radially inner arcuate wall surface;

the second support rib consists of one arch shaped segment axially aft on the shroud segment body radially outer surface of the first support rib and positioned generally axially aft and circumferentially between the pair of first support rib segments to define a triangle between the arcuate support wall surfaces of the first and second support rib segments, the support rib segment support wall surface of the second support rib defining an axial arcuate passage through the second support rib;

a first shroud hanger rib disposed in axial juxtaposition with the first support rib and carrying a pair of support pins respectively in juxtaposition with the radially inner arcuate wall surfaces of the pair of hook shaped rib segments; and

,

a second shroud hanger rib disposed in axial juxtaposition with the second support rib and carrying a support pin in juxtaposition with the support wall surface within the arcuate passage of the second support rib.

22. The shroud assembly of claim 14 in which:

the shroud segment is made of a low ductility material having a low tensile ductility, measured at room temperature to be no greater than about 1%;

the shroud segment support wall surface extending axially into the shroud segment support rib is arcuate radially to define a shroud segment arcuate support surface;

the at least one support pin comprises an arcuate outer surface extending generally axially from the hanger rib into the shroud segment support rib at the shroud segment arcuate support surface;

the clearance being sufficient to enable the relative axial movement as well as thermal expansion and contraction of the support pin and the segment support rib between the support segment arcuate support surface and the support pin arcuate outer surface.

23. The shroud assembly of claim 22 in which the low ductility material is a ceramic matrix composite material.