Turbine assembly with load pads

Patent metadata

Field	Value
Publication number	US-2016258304-A1
Application number	US-201615055004-A
Country	US
Kind code	A1
Filing date	Feb 26, 2016
Priority date	Mar 2, 2015
Publication date	Sep 8, 2016
Grant date	—

Abstract

A turbine shroud for a gas turbine engine includes a carrier and a blade track segment. The carrier is formed to include an inwardly opening blade track channel and the blade track segment is positioned in the blade track channel to couple the blade track segment with the carrier.

First claim

What is claimed is:

1 . A turbine shroud comprising
a metallic carrier arranged around a central axis, the metallic carrier formed to include a radially-inwardly opening blade track channel defined by a fore-retainer surface, an aft-retainer surface spaced apart axially from the fore-retainer surface, and an intermediate surface extending between the fore and aft-retainer surfaces, a ceramic blade track segment including a runner and an attachment body extending radially outward away from the runner and positioned in the blade track channel to couple the ceramic blade track segment with the metallic carrier, the attachment body including a fore-attachment surface that faces the fore-retainer surface, an aft-attachment surface that faces the aft-retainer surface, and an outer surface that faces the intermediate surface, and a plurality of load pads positioned in the blade track channel radially inward of the outer surface included in the attachment body between the fore-retainer surface and the fore-attachment surface and between the aft-retainer surface and the aft-attachment surface to transmit loads between the metallic carrier and the ceramic blade track segment at predetermined locations on the fore and aft-attachment surfaces while allowing growth of the metallic carrier and the ceramic blade track segment at different rates during use of the turbine shroud.

2 . The turbine shroud of claim 1 , wherein each load pad includes an outer pad surface arranged to engage the metallic carrier, an inner pad surface spaced apart from the outer pad surface and arranged to engage the ceramic blade track segment, and at least two ramped surfaces that each extend away from the inner pad surface at an angle relative to the inner pad surface toward the outer pad surface.

3 . The turbine shroud of claim 1 , wherein the fore-retainer surface of the metallic carrier is formed to include a pad recess that extends into the fore-retainer surface and receives a portion of a load pad.

4 . The turbine shroud of claim 3 , wherein the fore-attachment surface is spaced apart from the fore-retainer surface and the load pad received in the pad recess extends beyond the pad recess into the blade track channel and engages the for-attachment surface.

5 . The turbine shroud of claim 1 , wherein the aft-retainer surface of the metallic carrier is formed to include a pad recess that extends into the aft-retainer surface to receive a portion of a load pad.

6 . The turbine shroud of claim 5 , wherein one of the plurality of load pads includes an outer pad surface positioned in the pad recess and engaged with the aft-retainer surface and an inner pad surface spaced apart from the outer pad surface and positioned in the blade track channel and engaged with the aft-attachment surface.

7 . The turbine shroud of claim 1 , wherein the aft-retainer surface is formed to include a first pad recess and a second pad recess spaced apart circumferentially from the first pad recess and the fore-retainer surface is formed to include a third pad recess located circumferentially about midway between the first and second pad recesses.

8 . The turbine shroud of claim 7 , wherein a load pad is positioned in each of the first, second, and third pad recesses and each load pad is coupled with the metallic carrier by an adhesive to block the load pads from moving out of the first, second, and third pad recesses.

9 . The turbine shroud of claim 1 , wherein the predetermined locations on the fore and aft-attachment surfaces are high strength areas of the ceramic blade track segment positioned away from an edge of the ceramic blade track segment.

10 . The turbine shroud of claim 1 , wherein the load pads are positioned in the predetermined locations on the fore and aft-attachment surfaces to locate peak mechanical loads in a different region than peak thermal loads acting on the ceramic blade track segment.

11 . The turbine shroud of claim 1 , wherein the fore-attachment surface is spaced apart from the fore-retainer surface and the aft-attachment surface is spaced apart from the aft-retainer surface.

12 . The turbine shroud of claim 1 , wherein the load pads comprise a nickel alloy.

13 . A method of assembling a turbine shroud for use in an engine, the method comprising
positioning load pads along a sidewall included in a blade track channel of a metallic carrier, moving an attachment body of a ceramic blade track segment relative to the metallic carrier and into the blade track channel to cause the load pads to engage the attachment body and transmit loads between the metallic carrier and the ceramic blade track segment through predetermined locations on the attachment body while allowing growth of the metallic carrier and the ceramic blade track segment at different rates during engine operation.

14 . The method of claim 13 , wherein the load pads include an outer pad surface engaged with the metallic carrier, an inner pad surface spaced apart from the outer pad surface and arranged to engage the ceramic blade track segment, and at least two ramped surfaces extending away from the inner pad surface toward the outer pad surface and the inner pad surface.

15 . The method of claim 14 , further comprising coupling the outer pad surface to the metallic carrier with an adhesive.

16 . The method of claim 13 , wherein the metallic carrier includes a radially extending fore-retainer sidewall and a radially extending aft-retainer sidewall that is spaced apart axially from the fore-retainer sidewall, the aft-retainer sidewall is formed to include a first pad recess and a second pad recess spaced apart circumferentially from the first pad recess and the fore-retainer sidewall is formed to include a third pad recess located circumferentially about midway between the first and second pad recesses.

17 . The method of claim 13 , further including moving the attachment body of the ceramic blade track segment relative to the metallic carrier and out of the blade track channel and disposing of the load pads.

18 . A method of assembly a turbine shroud comprising
providing a metallic carrier that is formed to include an inwardly-opening blade track channel and a radially extending retainer surface that forms a portion of the inwardly-opening blade track channel and a ceramic blade track segment that includes a radially extending attachment surface arranged to face the retainer surface, determining a first set of three-dimensional coordinates of a first desired load location on the radially extending retainer surface of the metallic carrier relative to a reference point, determining a second set of three-dimensional coordinates of a second desired load location on the radially extending attachment surface of the ceramic blade track segment relative to the reference point, and determining a three-dimensional size of a load pad based on the first and second set of three-dimensional coordinates.

19 . The method of claim 18 , wherein determining the three-dimensional size of the load pad is based on the difference between the second and first set of three-dimensional coordinates.

20 . The method of claim 19 , further comprising aligning the radially extending attachment surface with the radially extending retainer surface and moving the ceramic blade track segment relative to the metallic carrier to cause the ceramic blade track segment to be received in the blade track channel and cause the radially extending attachment surface to be engaged by the load pad at the se

Assignees

• Rolls Royce Corp
• Rolls Royce Nam Tech Inc

Inventors

• Sippel Aaron D
• Freeman Ted J
• Thomas David J
• Uskert Richard C
• Loftus Peter J
• Lazur Andrew J

Classifications

• F01D25/246 Primary

  Fastening of diaphragms or stator-rings · CPC title

• F05D2220/32

  in gas turbines · CPC title

• F05D2300/20

  Oxide or non-oxide ceramics · CPC title

• F05D2230/60

  Assembly methods · CPC title

• F05D2230/23

  by permanently joining parts together · CPC title