U.S. patent application number 13/827762 was filed with the patent office on 2014-09-18 for turbine shroud with spline seal.
The applicant listed for this patent is GENERAL ELECTRIC COMPANY. Invention is credited to Joseph C. Albers, Robert Proctor, Richard Russo, JR., Monty Lee Shelton.
Application Number | 20140271142 13/827762 |
Document ID | / |
Family ID | 51527710 |
Filed Date | 2014-09-18 |
United States Patent
Application |
20140271142 |
Kind Code |
A1 |
Albers; Joseph C. ; et
al. |
September 18, 2014 |
Turbine Shroud with Spline Seal
Abstract
A turbine shroud assembly comprises a honeycomb rub strip, a
metallic backsheet disposed along an upper edge of said honeycomb
seal structure, a shroud frame having a first rail and a second
rail disposed at lateral edges of said metallic backsheet, a first
support and a second support connected to the first rail and the
second rail, a spline extending axially in the first rail and the
second rail along laterally outer surfaces of the first rail and
the second rail and, a spline seal having a first edge and a second
opposite edge, the first edge disposed in each of the spline
grooves and the second opposite edge being capable of positioning
in an adjacent shroud assembly.
Inventors: |
Albers; Joseph C.; (Ft.
Wright, KY) ; Shelton; Monty Lee; (Loveland, OH)
; Proctor; Robert; (West Chester, OH) ; Russo,
JR.; Richard; (Windham, NH) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GENERAL ELECTRIC COMPANY |
Schenectady |
NY |
US |
|
|
Family ID: |
51527710 |
Appl. No.: |
13/827762 |
Filed: |
March 14, 2013 |
Current U.S.
Class: |
415/173.1 |
Current CPC
Class: |
F01D 11/122 20130101;
Y02T 50/60 20130101; Y02T 50/671 20130101; F05D 2240/57 20130101;
F05D 2220/32 20130101; F01D 11/005 20130101; F01D 11/127 20130101;
F01D 25/246 20130101; F05D 2240/11 20130101; F02C 7/28
20130101 |
Class at
Publication: |
415/173.1 |
International
Class: |
F01D 25/24 20060101
F01D025/24 |
Claims
1. A turbine shroud assembly comprising: a honeycomb rub strip; a
metallic backsheet disposed along an upper edge of said honeycomb
seal structure; a shroud frame having a first rail and a second
rail disposed at lateral edges of said metallic backsheet; a first
support and a second support connected to said first rail and said
second rail; a spline extending axially in said first rail and said
second rail along laterally outer surfaces of said first rail and
said second rail; and, a spline seal having a first edge and a
second opposite edge, said first edge disposed in each of said
spline grooves and said second opposite edge being capable of
positioning in an adjacent shroud assembly.
2. The turbine shroud assembly of claim 1, said rails being a cast
material.
3. The turbine shroud assembly of claim 1, said rails being
forged.
4. The turbine shroud assembly of claim 1, said rails being plate
material.
5. The turbine shroud assembly of claim 1, said supports being hook
shaped.
6. The turbine shroud assembly of claim 1, said hooks being
L-shaped.
7. The turbine shroud assembly of claim 1, at least one of said
supports being an overhang.
8. The turbine shroud assembly of claim 1, said supports being cast
and integrally formed with said first and second rails.
9. The turbine shroud assembly of claim 1, said supports being
formed from sheet metal.
10. The turbine shroud assembly of claim 1, said backsheet
extending aft beyond said second support.
11. The turbine shroud assembly of claim 1, at least a portion of
said backsheet extending circumferentially beyond said first and
second rails.
12. A turbine shroud assembly, comprising: a shroud frame having a
first rail and a second rail, said first rail and second rails
extending in an axial direction; a first support and a second
support extending between said first rail and said second rail in a
circumferential direction; a backsheet disposed along a lower
surface of said shroud frame; a honeycomb rub strip disposed on a
lower surface of said backsheet; a spline disposed along an outer
surface of said first rail and said second rail; a spline seal
disposed in said spline to inhibit radial air leakage between
adjacent assemblies.
13. The turbine shroud assembly of claim 12, said backsheet
extending from said first support to said second support.
14. The turbine shroud assembly of claim 12, said backsheet
extending beyond said second support.
15. The turbine shroud assembly of claim 12, said first and second
rails extending aft beyond said backsheet.
16. The turbine shroud assembly of claim 15, said spline extending
beyond said second support.
17. The turbine shroud assembly of claim 15 further comprising a
second spline disposed on said rails, aft of said second support.
Description
BACKGROUND
[0001] Present embodiments relate generally to a gas turbine
engine. More specifically, the present embodiments relate, but are
not limited to, reducing leakage at a in a low pressure turbine
section of a gas turbine engine.
[0002] A typical gas turbine engine generally possesses a forward
end and an aft end with its several core or propulsion components
positioned axially therebetween. An air inlet or intake is located
at a forward end of the engine. Moving toward the aft end, in
order, the intake is followed by a fan, a compressor, a combustion
chamber, and a turbine. It will be readily apparent from those
skilled in the art that additional components may also be included
in the engine, such as, for example, low-pressure and high-pressure
compressors, and low-pres sure and high-pressure turbines. This,
however, is not an exhaustive list.
[0003] The compressor and turbine generally include rows of
airfoils that are stacked axially in stages. Each stage includes a
row of circumferentially spaced stator vanes and a row of rotor
blades which rotate about a center shaft or axis of the turbine
engine. A multi-stage low pressure turbine follows the multi-stage
high pressure turbine and is typically joined by a second shaft to
a fan disposed upstream from the compressor in a typical turbo fan
aircraft engine configuration for powering an aircraft in
flight.
[0004] The stator is formed by a plurality of nozzle segments which
are abutted at circumferential ends to form a complete ring about
the axis of the gas turbine engine. Each nozzle segment may
comprise a single vane, commonly referred to as a singlet.
Alternatively, a nozzle segment may have two vanes per segment,
which are generally referred to as doublets. In a third embodiment,
additional numbers of vanes may be disposed on a single segment. In
these embodiments, the vanes extend between an inner band and an
outer band.
[0005] A typical gas turbine engine utilizes a high pressure
turbine and low pressure turbine to maximize extraction of energy
from high temperature combustion gas. The turbine section typically
has an internal shaft axially disposed along a center longitudinal
axis of the engine. The blades are circumferentially distributed on
a rotor causing rotation of the internal shaft. The internal shaft
is connected to the rotor and the air compressor, such that the
turbine provides a rotational input to the air compressor to drive
the compressor blades. This powers the compressor during operation
and subsequently drives the turbine. As the combustion gas flows
downstream through the turbine stages, energy is extracted
therefrom and the pressure of the combustion gas is reduced.
[0006] In operation, air is pressurized in a compressor and mixed
with fuel in a combustor for generating hot combustion gases which
flow downstream through turbine stages. These turbine stages
extract energy from the combustion gases. A high pressure turbine
first receives the hot combustion gases from the combustor and
includes a stator nozzle assembly directing the combustion gases
downstream through a row of high pressure turbine rotor blades
extending radially outwardly from a supporting rotor disk. The
stator nozzles turn the hot combustion gas in a manner to maximize
extraction at the adjacent downstream turbine blades. In a two
stage turbine, a second stage stator nozzle assembly is positioned
downstream of the first stage blades followed in turn by a row of
second stage rotor blades extending radially outwardly from a
second supporting rotor disk. The turbine converts the combustion
gas energy to mechanical energy.
[0007] During such operation of the gas turbine engine, it is
desirable to minimize thermally induced deformation of the outer
casing through the turbine section of the engine. This is
accomplished, according to some embodiments, by isolating the outer
casing from heat produced by the hot combustion gases flowing
through the turbine. Turbine shrouds are connected to the engine
casing to provide an outer boundary flow for the combustion gas
limiting high temperature combustion gas from adversely affecting
the casing. The shroud extends circumferentially to form a ring
shape and may be formed of a plurality of circumferentially
extending shroud segments. However, as combustion gas moves
radially outward with rotation of the turbine blades, the
combustion gas can pass through axial seams between the adjacent
shroud segments. This is not optimal and results in energy
losses.
[0008] It would be desirable to overcome these and other
deficiencies with turbine sections of gas turbine engines. More
specifically it would be desirable to provide a restriction in at
least a radial direction to flow of combustion gas between shroud
segments.
SUMMARY
[0009] According to some embodiments, a shroud includes a spline
seal to limit combustion gas from leaking between adjacent shroud
segment assemblies while also reducing weight. An after spline seal
may be housed within aft rail portions of the assembly. In addition
or alternatively to this embodiment, a backsheet may have portions
which extending beyond a frame boundary to create overlap with
adjacent backsheet portions.
[0010] According to some embodiments, a turbine shroud assembly
comprises a honeycomb rub strip, a metallic backsheet disposed
along an upper edge of said honeycomb seal structure, a shroud
frame having a first rail and a second rail disposed at lateral
edges of said metallic backsheet, a first support and a second
support connected to the first rail and the second rail, a spline
extending axially in the first rail and the second rail along
laterally outer surfaces of the first rail and the second rail and,
a spline seal having a first edge and a second opposite edge, the
first edge disposed in each of the spline grooves and the second
opposite edge being capable of positioning in an adjacent shroud
assembly.
[0011] All of the above outlined features are to be understood as
exemplary only and many more features and objectives of the turbine
shroud with spline seal may be gleaned from the disclosure herein.
Therefore, no limiting interpretation of this summary is to be
understood without further reading of the entire specification,
claims, and drawings included herewith.
BRIEF DESCRIPTION OF THE ILLUSTRATIONS
[0012] The above-mentioned and other features and advantages of
these exemplary embodiments, and the manner of attaining them, will
become more apparent and the turbine shroud with spline seal
feature will be better understood by reference to the following
description of embodiments taken in conjunction with the
accompanying drawings, wherein:
[0013] FIG. 1 is a side section view of an exemplary gas turbine
engine;
[0014] FIG. 2 is an isometric view of a shroud assembly segment of
instant embodiments;
[0015] FIG. 3 is an exploded assembly view of the shroud assembly
segment of FIG. 2;
[0016] FIG. 4 is a axial view of two shroud assembly segments;
[0017] FIG. 5 is an isometric view of an alternate embodiment of a
shroud assembly segment;
[0018] FIG. 6 is a side view of an alternate shroud assembly
segment.
DETAILED DESCRIPTION
[0019] Reference now will be made in detail to embodiments
provided, one or more examples of which are illustrated in the
drawings. Each example is provided by way of explanation, not
limitation of the disclosed embodiments. In fact, it will be
apparent to those skilled in the art that various modifications and
variations can be made in the present embodiments without departing
from the scope or spirit of the disclosure. For instance, features
illustrated or described as part of one embodiment can be used with
another embodiment to still yield further embodiments. Thus it is
intended that the present invention covers such modifications and
variations as come within the scope of the appended claims and
their equivalents.
[0020] Referring to FIGS. 1-6, various embodiments of a gas turbine
engine are depicted having a turbine shroud with spline seal. The
shroud includes a spline for locating a spline seal between an
adjacent spline. The shroud may also have a back sheet extending in
an aft direction to limit leakage aft of the shroud. In addition to
limiting weight, it is desirable to reduce weight.
[0021] As used herein, the terms "axial" or "axially" refer to a
dimension along a longitudinal axis of an engine. The term
"forward" used in conjunction with "axial" or "axially" refers to
moving in a direction toward the engine inlet, or a component being
relatively closer to the engine inlet as compared to another
component. The term "aft" used in conjunction with "axial" or
"axially" refers to moving in a direction toward the engine nozzle,
or a component being relatively closer to the engine nozzle as
compared to another component.
[0022] As used herein, the terms "radial" or "radially" refer to a
dimension extending between a center longitudinal axis of the
engine and an outer engine circumference. The use of the terms
"proximal" or "proximally," either by themselves or in conjunction
with the terms "radial" or "radially," refers to moving in a
direction toward the center longitudinal axis, or a component being
relatively closer to the center longitudinal axis as compared to
another component. The use of the terms "distal" or "distally,"
either by themselves or in conjunction with the terms "radial" or
"radially," refers to moving in a direction toward the outer engine
circumference, or a component being relatively closer to the outer
engine circumference as compared to another component. As used
herein, the terms "lateral" or "laterally" refer to a dimension
that is perpendicular to both the axial and radial dimensions.
[0023] Referring initially to FIG. 1, a schematic side section view
of a gas turbine engine 10 is shown. The function of the gas
turbine engine is to extract energy from high pressure and
temperature combustion gases and convert the energy into mechanical
energy for work. The gas turbine engine 10 has an engine inlet end
12 wherein air enters the core or propulsor 13 which is defined
generally by a compressor 14, a combustor 16 and a multi-stage high
pressure turbine 20. Collectively, the propulsor 13 provides thrust
or power during operation. The gas turbine 10 may be used for
aviation, power generation, industrial, marine or the like.
[0024] In operation air enters through the air inlet end 12 of the
engine 10 and moves through at least one stage of compression where
the air pressure is increased and directed to the combustor 16. The
compressed air is mixed with fuel and burned providing the hot
combustion gas which exits the combustor 16 toward the high
pressure turbine 20. At the high pressure turbine 20, energy is
extracted from the hot combustion gas causing rotation of turbine
blades which in turn cause rotation of the shaft 24. The shaft 24
passes toward the front of the engine to continue rotation of the
one or more compressor stages 14, a turbofan 18 or inlet fan
blades, depending on the turbine design. The turbofan 18 is
connected by the shaft 28 to a low pressure turbine 21 and creates
thrust for the turbine engine 10. A low pressure turbine 21 may
also be utilized to extract further energy and power additional
compressor stages.
[0025] Referring now to FIG. 2, an isometric view of a shroud
assembly segment 30 is depicted. Instant embodiments of the shroud
segment assembly 30 are located in the low pressure turbine 21 area
of the engine 10 (FIG. 1). The instant segment assembly 30
embodiment is a one-piece cast hook and rail assembly. The
embodiment utilizes a frame 31 comprising a first rail 32 and a
second rail 34 which extend in a generally axial direction parallel
to the gas turbine engine axis 26 (FIG. 1) or alternatively may be
at an acute angle relative to the axis 26. Extending laterally or
in the circumferential direction between the first and second rails
32, 34 the frame 31 further comprises a first or forward support 40
and a second or aft support 42. The shroud assembly segment 30
includes forward tips 44 and may include aft tips 46, 47 extending
from the aft support 42. As described further, the rails 32, 34 may
be formed of various cross-sections and may be of various
materials. Similarly, the supports 40, 42 may have various shapes
and may be formed of various materials and formed by a variety of
manufacturing processes.
[0026] The rails 32, 34 include a slot or spline 39 disposed on
circumferential ends or slash face surfaces 36, 38. The splines 39
extend along the surfaces 36, 38 to receive a spline seal 37. The
spline seal 37 is positioned at one circumferential end to a first
segment 30 and at a second circumferential end to a
circumferentially adjacent segment (not shown). As turbine blades
move radially beneath, the combustion gas moves both radially and
axially. The spline seal 37 precludes combustion gas moving within
the turbine from passing in a radial direction between segments 30
defining the shroud.
[0027] Referring now to FIG. 3, an exploded assembly view of the
shroud assembly segment 30 is depicted in isometric view. First,
the shroud frame 31 includes a cast structure having the rails 32,
34 integrally joined to supports 40, 42. According to alternative
embodiments, the frame 31 may be forged, cast, direct metal laser
sintered or as a further alternative may be formed of metallic
plate or bar material. The rails 32, 34 may alternatively be formed
of back sheet stock or other materials and of various
cross-sectional shapes.
[0028] The supports 40, 42 may take various shapes described
further herein. According to the instant embodiment, the supports
40, 42 are hook-shaped which may include various cross-sections.
For example, the depicted supports 40, 42 are generally inverted
L-shaped structures extending vertically from, and between, the
rails 32, 34. According to the instant embodiment, the supports 40,
42 are integrally formed with the rails 32, 34. As previously
described, the rails 32, 34 have tips 44 at forward ends for aiding
connection with an engine casing. A gap 45 is defined between the
upper axial legs 41, 43 of the support 40, 42 and the rail tips 44.
In the instant embodiment, a similar gap is also defined between
the upper leg of the aft support 42 and the rails 32, 34. The gaps
45 receive a flange of the engine casing for mounting of the shroud
assembly segment 30. It should be understood by one skilled in the
art that the supports 40, 42 are not limited to the L-shape shown
but alternatively may be Z-shaped, C-shaped, straight or other
shapes allowing the structure to be retained by the engine casing.
Additionally, the supports 40, 42 and/or lower rail surfaces may be
curved to approximate the curvature of the engine casing.
[0029] The splines 39 are also positioned in the lateral or
circumferentially outer faces 36, 38 of the rails 32, 34. Each
spline 39 allows for receiving a spline seal 37 to engage with an
adjacent assembly segment 30. The spline seal 37 inhibits radial
leakage of air between the segments 30. More specifically, since
the segments 30 are circumferentially adjacent to one another,
axial seams are formed between adjacent shroud assembly segments
30. The spline seal 37 limits combustion gas from leaking through
such seams.
[0030] As depicted in broken line, the exemplary spline seal 37 is
rectangular in shape, but may form a variety of shapes. For
example, the seal structure 37 may be circular, square,
rectangular, other polygons or geometries. The seal 37 may be
formed of a singular material or may be a multi-material structure.
The seal 37 may change shape at operating temperature as well. The
seal 37 has a volumetric thermal expansion coefficient which is a
thermodynamic property of the material. For example, the volumetric
thermal expansion can be expressed as
.alpha..sub.V=(1/v)(.DELTA.V/.DELTA.T), where .alpha..sub.V is the
volumetric thermal expansion coefficient, V is the volume of the
material and .DELTA.V/.DELTA.T with respect to the change in volume
of the material with respect to the change in temperature of the
material. Thus the volumetric thermal expansion coefficient
measures the fractional change in volume per degree change in
temperature at a constant temperature.
[0031] When viewed in a forward looking aft direction, the adjacent
shroud assembly segments 30 are positioned in their annular
arrangement, the seals 37 are positioned in each adjacent spline 39
to block an air flow path which would otherwise allow flow between
adjacent assembly segments 30.
[0032] Extending across the bottom surfaces of the rails 32, 34 is
a backsheet 50 which may be, for example, metallic or various
materials. The shield 50 is designed to extend in aft and
circumferential directions of the shroud frame 31 so as to define a
flow path along a radially inner side of the shroud frame 31. The
backsheet 50 is sized to extend circumferentially between lateral
ends of the rails 32, 34 to the opposite circumferential end of
rail 34. The shield 50 also extends, in some embodiments, in an
axial direction from forward end of the rails 32, 34 to aft ends of
the rails 32, 34. As depicted in the embodiment, the backsheet 50
may have a thickness which is less than prior art backsheet
structures since the cast rails 32, 34 provide additional strength.
The instant embodiment depicts the back sheet or shield 50 being of
a constant thickness. However, according to some embodiments, the
back sheet 50 may be formed of variable thickness. For example,
areas which may be expected to receive impact from a detached rotor
blade may have an increased thickness to dissipate energy of such
ejected blade while areas adjacent the rails 32, 34 or supports 40,
42 are of thinner dimension radially. Similarly, while thicknesses
of the rails 32, 34 are generally shown as constant, alternative
embodiments may utilize rails of varying thickness.
[0033] In addition to the first portion 52 of the sheet 50,
described above, the backsheet 50 may also include a second portion
54. The second portion 54 of the shield 50 extends from an aft edge
53 of the first portion 52. The first and second portions 52, 54
may be formed of a single sheet of metal as shown in the depicted
view and bent or alternatively, may be joined from two separate
pieces such as by welding or brazing. In a third alternative, the
two pieces may be abutted against one another but not joined to one
another. Instead, the first portion 52 may be joined with the frame
31 and the second portion 54 also joined with the frame 31 but the
first and second portions 52, 54 closely abutting one another.
[0034] The frame 31 includes aft tips 46, 47 extend from the aft
side of support 42 and are formed at an angle to the rails 32, 34.
The angle of the tips 46, 47 approximate the angle of the second
portion 54 relative to the first portion 52 of metallic sheet
shield 50. These tips 46, 47 may be formed integrally with the
frame 31 or may be joined in a separate manufacturing step to
extend from the frame 31, for example welding or brazing.
[0035] According to one embodiment, the tips 46, 47 may also
include splines 49 within circumferential end surfaces of these
structures. This allows for the additional spline seal 51 to be
utilized in this area of the frame 31 inhibiting radial leakage
between adjacent shroud assembly segments 30. In an embodiment
utilizing the spline 49, the spline 49 may be formed continuously
with spline 39 so that a single spline seal may be utilized.
Alternatively, the spline 49 may be formed separately from but
closely abut spline 39 and minimize any gap between these spline
seal elements. In a further alternative, the spline 49 may be
welded or brazed to spline 39 or may closely abut spline 39.
[0036] In still a further alternative, the second backsheet
portions 54 may be widened in the circumferential direction so as
to overlap second portions 54 of an adjacent backsheet 50. This is
shown in the embodiment as the optional back sheet portion in
broken lines. This may eliminate the need or desire to have the
spline seal 49 located in these tips 46, 47. Thus in either
embodiment, leakage aft of the second support 42 is limited.
[0037] Referring still to FIG. 3, a honeycomb rub strip 60 is
positioned beneath the sheet shield 50. The honeycomb structure 60
is joined for example, mechanically, bonded, welded or brazed,
directly to the back sheet 50 and is sized to extend
circumferentially between the rails 32, 34 and axially from the
tips 44 to the aft support 42. The aft end of the honeycomb 60 may
be cut on an angle to approximate the angle of the second portion
54 of the metallic back sheet 50 if such is utilized. The honeycomb
rub strip 60 may take any of various conventional forms. The rub
strip 60 may have a thickness in a radial direction so that it is
radially inner surface spaced from a turbine tip to provide a
minimal clearance gap therebetween. The honeycomb rub strip 60 may
further include an abradable radially inner surface and define an
outer boundary for the passage of hot combustion gas through the
turbine section of the engine 10 (FIG. 1). Additionally, the
radially outward ends of the turbine blades 23 (FIG. 5) may include
sealing fins 25 (FIG. 5) abutting the abradable surface 62 of the
honeycomb rub strip 60. The honeycomb rub strip 60 may be deformed
by these sealing fins during rotation of the rotor blades 23 such
that a nearly zero tolerance fit is defined between the honeycomb
lower surface 62 and the sealing fins 25 of the rotor blades. This
reduces the leakage of combustion gas through the turbine section
of the engine 10.
[0038] Referring now to FIG. 4, an aft looking forward view of
adjacent assembly segments is depicted. Each of the segments is
joined by a spline seal 37 at slash face ends. Accordingly, the
structure provides a circumferential design which lines the inner
surface of the engine case to retain high temperature combustion
gas on the lower side, as depicted, of the assembly segments 30 and
inhibiting deformation of the engine casing along the outer
perimeter of the assembly segments 30. As depicted, the spline seal
37 inhibit high temperature combustion gas from escaping between
the axially extending gaps between adjacent assembly segments 30.
The gaps in the depicted embodiment are exaggerated for ease of
understanding, as one skilled in the art will understand. According
to additional embodiments, the backsheets 50 may be extended in the
circumferential direction to aid in reducing leakage near the aft
end of the assembly segments 30. These sheets 50 may overlap to aid
in reducing leakage between the assembly segments 30.
[0039] Referring now to FIG. 5, an alternative embodiment is
depicted for an exemplary shroud assembly segment 130. According to
this embodiment the frame 131, defined by the rails 132, 134 and
supports 140, 142 are not a one-piece structure. Instead, the rails
132, 134 are formed independently from the supports 140, 142. The
rails 132, 134 may be formed of cast rails, plate material or
forged material in bar sheet stock form and may be formed of
various cross-sections. Additionally, in order decrease weight, the
supports 140, 142 are formed of sheet metal and are depicted to
have an inverted L-shape although other cross sections may be
utilized. In the instant embodiment, the sheet metal supports 140,
142 are welded or otherwise bonded to the rails 132, 134. As an
alternative, the rails 132, 134 may be formed of thickened sheet
metal. In either embodiment, it is preferable that the sheet metal
or the cast metal be thick enough to provide for formation of a
spline 139 extending in the axial direction of the circumferential
end faces of the rails 132, 134. In the previous embodiment, the
rails may or may not include a spline which is continuous or
discontinuous from spline 149. If a spline 149 is not used, it may
be desirable to widen the sheet metal shield 150 so that adjacent
sheets overlap aft of the second rail 142 to further limit leakage
in these areas.
[0040] Referring now to FIG. 6, a side view of an alternate shroud
assembly segment 230 is depicted in an assembled view within a
turbine section. The structure depicts views of a forward support
240 and a rear support 242 which is linear defining a shoulder,
rather than the inverted L-shape previously described. These
structures may be formed of a plurality of materials including but
not limited to bar stock, plate stock, cast materials, forged
materials and sheet metallics, including alloys. It should be
understood from this description as well as the previous
descriptions, that various cross sections may be utilized to define
the support structures for any of shroud assembly segments.
[0041] While multiple inventive embodiments have been described and
illustrated herein, those of ordinary skill in the art will readily
envision a variety of other means and/or structures for performing
the function and/or obtaining the results and/or one or more of the
advantages described herein, and each of such variations and/or
modifications is deemed to be within the scope of the invent of
embodiments described herein. More generally, those skilled in the
art will readily appreciate that all parameters, dimensions,
materials, and configurations described herein are meant to be
exemplary and that the actual parameters, dimensions, materials,
and/or configurations will depend upon the specific application or
applications for which the inventive teachings is/are used. Those
skilled in the art will recognize, or be able to ascertain using no
more than routine experimentation, many equivalents to the specific
inventive embodiments described herein. It is, therefore, to be
understood that the foregoing embodiments are presented by way of
example only and that, within the scope of the appended claims and
equivalents thereto, inventive embodiments may be practiced
otherwise than as specifically described and claimed. Inventive
embodiments of the present disclosure are directed to each
individual feature, system, article, material, kit, and/or method
described herein. In addition, any combination of two or more such
features, systems, articles, materials, kits, and/or methods, if
such features, systems, articles, materials, kits, and/or methods
are not mutually inconsistent, is included within the inventive
scope of the present disclosure.
[0042] Examples are used to disclose the embodiments, including the
best mode, and also to enable any person skilled in the art to
practice the apparatus and/or method, including making and using
any devices or systems and performing any incorporated methods.
These examples are not intended to be exhaustive or to limit the
disclosure to the precise steps and/or forms disclosed, and many
modifications and variations are possible in light of the above
teaching. Features described herein may be combined in any
combination. Steps of a method described herein may be performed in
any sequence that is physically possible.
[0043] All definitions, as defined and used herein, should be
understood to control over dictionary definitions, definitions in
documents incorporated by reference, and/or ordinary meanings of
the defined terms. The indefinite articles "a" and "an," as used
herein in the specification and in the claims, unless clearly
indicated to the contrary, should be understood to mean "at least
one." The phrase "and/or," as used herein in the specification and
in the claims, should be understood to mean "either or both" of the
elements so conjoined, i.e., elements that are conjunctively
present in some cases and disjunctively present in other cases.
[0044] It should also be understood that, unless clearly indicated
to the contrary, in any methods claimed herein that include more
than one step or act, the order of the steps or acts of the method
is not necessarily limited to the order in which the steps or acts
of the method are recited.
[0045] In the claims, as well as in the specification above, all
transitional phrases such as "comprising," "including," "carrying,"
"having," "containing," "involving," "holding," "composed of," and
the like are to be understood to be open-ended, i.e., to mean
including but not limited to. Only the transitional phrases
"consisting of" and "consisting essentially of" shall be closed or
semi-closed transitional phrases, respectively, as set forth in the
United States Patent Office Manual of Patent Examining Procedures,
Section 2111.03.
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