U.S. patent application number 13/799062 was filed with the patent office on 2013-07-18 for spring loaded seal assembly for turbines.
This patent application is currently assigned to GENERAL ELECTRIC COMPANY. The applicant listed for this patent is GENERAL ELECTRIC COMPANY. Invention is credited to Mehmet Demiroglu, Kevin Weston McMahan, Timur Rustamovich Repikov.
Application Number | 20130181413 13/799062 |
Document ID | / |
Family ID | 44118194 |
Filed Date | 2013-07-18 |
United States Patent
Application |
20130181413 |
Kind Code |
A1 |
McMahan; Kevin Weston ; et
al. |
July 18, 2013 |
SPRING LOADED SEAL ASSEMBLY FOR TURBINES
Abstract
A spring loaded seal assembly is disclosed for sealing a gap
between adjacent turbine components. The seal assembly may
generally include a turbine seal and a spring member. The turbine
seal may extend between the adjacent turbine components and may be
configured to seal the gap defined between the turbine components.
The spring member may be configured to engage the turbine seal so
as to maintain the seal in sealing engagement with the adjacent
turbine components.
Inventors: |
McMahan; Kevin Weston;
(Greer, SC) ; Repikov; Timur Rustamovich; (Moscow,
RU) ; Demiroglu; Mehmet; (Troy, NY) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
GENERAL ELECTRIC COMPANY; |
Schenectady |
NY |
US |
|
|
Assignee: |
GENERAL ELECTRIC COMPANY
Schenectady
NY
|
Family ID: |
44118194 |
Appl. No.: |
13/799062 |
Filed: |
March 13, 2013 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
12797272 |
Jun 9, 2010 |
8398090 |
|
|
13799062 |
|
|
|
|
Current U.S.
Class: |
277/641 |
Current CPC
Class: |
F05D 2250/71 20130101;
F05D 2240/57 20130101; F01D 9/023 20130101; F16J 15/061 20130101;
F05D 2250/38 20130101; F05D 2250/611 20130101; F02C 7/28 20130101;
F01D 11/005 20130101; F01D 11/00 20130101; F16J 15/0887
20130101 |
Class at
Publication: |
277/641 |
International
Class: |
F02C 7/28 20060101
F02C007/28; F16J 15/06 20060101 F16J015/06; F01D 11/00 20060101
F01D011/00 |
Claims
1. A spring loaded seal assembly for sealing a fluid leakage gap
between adjacent turbine components, the spring loaded seal
assembly comprising: a turbine seal extending between aligned seal
grooves defined in adjacent stationary turbine components, said
turbine seal configured to seal a fluid leakage gap defined between
said turbine components; and at least one spring member configured
to maintain said turbine seal in sealing engagement with said
turbine components, said at least one spring member extending
between said aligned seal grooves and being attached to said
turbine seal.
2. The spring loaded seal assembly of claim 1, wherein said at
least one spring member is biased against a forward surface of said
aligned seal grooves.
3. The spring loaded seal assembly of claim 1, wherein said at
least one spring member is bowed along its length.
4. The spring loaded seal assembly of claim 3, wherein said at
least one spring member is attached to a side of said turbine seal
such that said at least one spring member is bowed concavely with
respect to said side.
5. The spring loaded seal assembly of claim 3, wherein said at
least one spring member is attached to a side of said turbine seal
such that said at least one spring member is bowed convexly with
respect to said side.
6. The spring loaded seal assembly of claim 1, wherein said at
least one spring member comprises a horizontal segment attached to
said turbine seal and first and second arms extending from said
horizontal segment, said first and second arms being biased against
a forward surface of said aligned seal grooves.
7. The spring loaded seal assembly of claim 6, wherein said first
and second arms extend from said horizontal segment at an acute
angle.
8. The spring loaded seal assembly of claim 6, wherein said first
and second arms are formed from a resilient material.
9. The spring loaded seal assembly of claim 1, wherein said at
least one spring member extends longitudinally along the length of
said turbine seal.
10. The spring loaded seal assembly of claim 1, wherein said at
least one spring member is configured as a leaf spring.
11. The spring loaded seal assembly of claim 1, wherein said at
least one spring member is segmented along its length.
Description
RELATED APPLICATIONS
[0001] The present application is a divisional of U.S. patent
application No. 12/797,272, filed on Jun. 9, 2010, the disclosure
of which is hereby incorporated by reference herein in its entirety
for all purposes.
FIELD OF THE INVENTION
[0002] The present subject matter relates generally to turbine
seals for turbine assemblies and particularly to a spring loaded
seal assembly for sealing a gap between adjacent turbine
components.
BACKGROUND OF THE INVENTION
[0003] Turbine assemblies may include, without limitation, turbine
sections of steam turbines and compressor and/or turbine sections
of gas turbines. A steam turbine has a steam path which typically
includes a steam inlet, a turbine and a steam outlet. A gas turbine
has a gas path which typically includes an air intake (or inlet), a
compressor, a combustor, a turbine and a gas outlet (or exhaust
nozzle). Gas or steam leakage, either out of the gas or steam path
or into the gas or steam path, from an area of higher pressure to
an area of lower pressure is generally undesirable. For example,
gas-path leakage in the turbine or compressor area of a gas
turbine, between the rotor of the turbine or compressor and the
circumferentially surrounding turbine or compressor casing, will
lower the efficiency of the gas turbine leading to increased fuel
costs. Additionally, gas-path leakage in the combustor section of a
gas turbine will require an increase in burn temperature to
maintain the power level, with such increased burn temperatures
leading to increased emissions, such as increased NOx production.
Further, steam-path leakage in the turbine area of a steam turbine,
between the rotor of the turbine and the circumferentially
surrounding casing, will lower the efficiency of the steam turbine
leading to increased fuel costs.
[0004] Turbine seals are typically used to minimize the leakage of
fluids in a turbine assembly. As is generally known, side or spline
seals may often be utilized for sealing gaps between adjacent
turbine components. For example, elongated metallic cloth seals are
known for sealing the sides between adjacent turbine components,
such as circumferentially-adjacent transition pieces. However, such
seals are typically pressure loaded only, relying primarily on high
pressure fluids, such as compressor discharge air, contacting a
high pressure side of the turbine seal to maintain the seal in
sealing engagement with the adjacent turbine components. With
regard to pressure loaded seals, it has been found that there can
be significant leakage between the sealed turbine components when
the seal becomes warped and/or gaps develop between the seal and
the corners of the turbine components. Moreover, current pressure
loaded turbine seals often become unseated from and/or fail to
conform to the sealing surfaces of the adjacent turbine components,
thereby permitting further leakage between the components.
[0005] Accordingly, a seal assembly that minimizes the potential
for leakage between adjacent turbine components would be welcomed
in the technology.
BRIEF DESCRIPTION OF THE INVENTION
[0006] Aspects and advantages of the invention will be set forth in
part in the following description, or may be obvious from the
description, or may be learned through practice of the
invention.
[0007] In one aspect, the present subject matter provides a spring
loaded seal assembly for sealing a fluid leakage gap between
adjacent turbine components. The seal assembly may generally
include a turbine seal and a spring member. The turbine seal may
extend between the adjacent turbine components and may be
configured to seal the gap defined between the turbine components.
The spring member may be configured to maintain the seal in sealing
engagement with the adjacent turbine components and may have a
width less than the width of the fluid leakage gap.
[0008] In another aspect, the present subject matter provides a
spring loaded seal assembly for sealing a fluid leakage gap between
adjacent turbine components. The seal assembly may generally
include a turbine seal and at least one spring member. The turbine
seal may extend between aligned seal grooves defined in the
adjacent turbine components and may be configured to seal the gap
defined between the turbine components. The at least one spring
member may be configured to maintain the seal in sealing engagement
with the adjacent turbine components. Additionally, the at least
one spring member may extend between the aligned seal grooves and
may be attached to the turbine seal.
[0009] These and other features, aspects and advantages of the
present invention will become better understood with reference to
the following description and appended claims. The accompanying
drawings, which are incorporated in and constitute a part of this
specification, illustrate embodiments of the invention and,
together with the description, serve to explain the principles of
the invention.
BRIEF DESCRIPTION OF THE DRAWING
[0010] A full and enabling disclosure of the present invention,
including the best mode thereof, directed to one of ordinary skill
in the art, is set forth in the specification, which makes
reference to the appended figures, in which:
[0011] FIG. 1 illustrates a front view of an embodiment of a spring
loaded seal assembly installed between adjacent turbine components
in accordance with an aspect of the present subject matter;
[0012] FIG. 2 illustrates a perspective view of the embodiment of
the spring loaded seal assembly depicted in FIG. 1 in accordance
with an aspect of the present subject matter;
[0013] FIG. 3 illustrates a cross-sectional side view of the
embodiment of the spring loaded seal assembly depicted in FIG. 1 in
accordance with an aspect of the present subject matter;
[0014] FIG. 4 illustrates a perspective view of another embodiment
of a spring loaded seal assembly in accordance with an aspect of
the present subject matter;
[0015] FIG. 5 illustrates a partial plan view of the embodiment of
the spring loaded seal assembly depicted in FIG. 4 installed
between adjacent turbine components in accordance with an aspect of
the present subject matter;
[0016] FIG. 6 illustrates a perspective view of a further
embodiment of a spring loaded seal assembly in accordance with an
aspect of the present subject matter;
[0017] FIG. 7 illustrates a perspective view of yet another
embodiment of a spring loaded seal assembly in accordance with an
aspect of the present subject matter;
[0018] FIG. 8 illustrates a perspective view of still a further
embodiment of a spring loaded seal assembly in accordance with an
aspect of the present subject matter;
[0019] FIG. 9 illustrates a perspective view of still another
embodiment of a spring loaded seal assembly in accordance with an
aspect of the present subject matter; and
[0020] FIG. 10 illustrates a perspective view of another embodiment
of a spring loaded seal assembly in accordance with an aspect of
the present subject matter.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Reference now will be made in detail to embodiments of the
invention, one or more examples of which are illustrated in the
drawings. Each example is provided by way of explanation of the
invention, not limitation of the invention. In fact, it will be
apparent to those skilled in the art that various modifications and
variations can be made in the present invention without departing
from the scope or spirit of the invention. For instance, features
illustrated or described as part of one embodiment can be used with
another embodiment to yield a still further embodiment. 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.
[0022] In general, the present subject matter is directed to a
spring loaded seal assembly for use between adjacent turbine
components. The spring loaded seal assembly may include both a
turbine seal and a spring member. Generally, the spring member of
the spring loaded seal assembly may be configured to reduce turbine
seal leakage by providing a spring seating or biasing force along
at least a portion of the length of the seal and at the corners of
the adjacent turbine components. This spring seating force or
spring loading may be in addition to the pressure loading already
present on the turbine seal. Thus, with such loading, the spring
loaded seal assembly may ensure that the turbine seal conforms to
the seal grooves defined in the adjacent turbine components and,
thereby reduce the leakage area. This may improve overall turbine
performance by reducing or eliminating many of the problems
associated with turbine seal leakage, such as imposing an emissions
and performance penalty by limiting the T-fire of a turbine
assembly.
[0023] Referring to the drawings, FIGS. 1-3 illustrate one
embodiment of a spring loaded seal assembly 10 for sealing a fluid
leakage gap 12 between adjacent turbine components 14,16 in
accordance with an aspect of the present subject matter.
Particularly, FIG. 1 illustrates a front view of an embodiment of a
spring loaded seal assembly 10 installed between adjacent turbine
components 14,16. FIG. 2 illustrates a perspective view of the
embodiment of the spring loaded seal assembly 10, particularly
showing the spring loaded seal assembly 10 with one of the turbine
components 14,16 removed for purposes illustration. Finally, FIG. 3
illustrates a cross-sectional, side view of the embodiment of the
spring loaded seal assembly 10 as installed between adjacent
turbine components 14,16.
[0024] The spring loaded seal assembly 10 may include a turbine
seal 18 and a spring member 20. The turbine seal 18 may generally
extend between the adjacent turbine components 14,16, such as
between adjacent stationary or static components, and may be
configured to seal a fluid leakage gap 12 defined between the
adjacent turbine components 14,16. The spring member 20 may be
generally disposed lengthwise along the turbine seal 18.
Additionally, the spring member 20 may be configured to maintain
the turbine seal 18 in sealing engagement with the adjacent turbine
components 14,16 in order to prevent turbine seal leakage through
the fluid-path leakage gap 12. One of ordinary skill in the art
should appreciate that a fluid-path leakage gap 12 may include,
without limitation, a steam-path leakage of a turbine of a steam
turbine, a compressed-air leakage gap of a compressor of a gas
turbine, and a combustion-gas leakage gap in the combustor of a gas
turbine or downstream of the combustor, such as in the transition
pieces and/or the first-stage nozzles.
[0025] Initially, it should be appreciated that the spring loaded
seal assembly 10 of the present subject matter may be utilized to
seal any fluid leakage gap 12 generally defined between any
adjacent components 14,16 of a turbine assembly. For example, FIG.
1 illustrates a front view of portions of a first turbine component
14 and a second turbine component 16 that may be sealed with the
spring loaded seal assembly 10 of the present subject matter. In
one embodiment, the first turbine component 14 and the second
turbine component 16 may comprise stationary turbine components.
The turbine components 14,16 may be disposed substantially
proximate to one another so as to define a fluid-leakage gap 12
therebetween. Additionally, the first turbine component 14 may
define a first seal groove 22 and the second turbine component 16
may define a second seal groove 24. The first and second seal
grooves 22,24 may generally face each other and may be
substantially aligned so as to permit a turbine seal 18 to extend
between the seal grooves 22,24. It should be appreciated that, in
one embodiment, the first and second turbine components 14,16 may
comprise circumferentially adjacent transition pieces of a gas
turbine. Thus, the spring loaded seal assembly 10 of the present
subject matter may be utilized to seal the gap defined between the
adjacent exit ends of two transition pieces, such as the adjacent,
generally rectilinear aft frames of the transition pieces.
[0026] It should also be readily appreciated that the turbine seal
18 of the spring loaded seal assembly 10 may generally comprise any
suitable seal known in the art for sealing a fluid leakage gap 12
defined between any adjacent turbine components 14,16. For example,
in one embodiment, the turbine seal 18 may comprise a side or
spline seal utilized to seal the fluid leakage gap 12 between
circumferentially adjacent transition pieces. Thus, one of ordinary
skill in the art should appreciate that the turbine seal 18 may
comprise a rigid or flexible elongated metallic member extending
between the adjacent turbine components 14,16. Alternatively, the
turbine seal 18 may comprise a more advanced seal, such as an
elongated cloth seal including both metallic cloth and an elongated
metal shim. For instance, turbine seals 18 that may be utilized
within the scope of the present subject matter include, without
limitation, the turbine seals disclosed in U.S. Pat. No. 6,162,014
(Bagepalli et al.) and U.S. Pub. No. 2003/0039542 (Cromer), both of
which are assigned to the common assignee. However, it should be
appreciated that various other turbine seal types/configurations
may be utilized within the scope of the present subject matter.
[0027] As indicated above, the turbine seal 18 may generally extend
between adjacent turbine components 14,16 so as to seal the gap 12
defined between the adjacent turbine components 14,16. Thus, it
should be appreciated that the turbine seal 18 may be configured to
be seated against and/or engage the sealing surfaces of the
adjacent turbine components 14,16. For example, as shown in FIGS. 1
and 3, the turbine seal 18 may extend between the aligned seal
grooves 22,24 of the first and second turbine components 14,16 such
that the seal 18 seats against and engages a sealing surface of the
seal grooves 22,24, such as an aft surface 26 (FIGS. 3 and 5) of
the seal grooves 20,22. It should be appreciated that a high
pressure side 28 of the turbine seal 18 may be generally exposed to
pressure loading which pushes/presses the turbine seal towards the
aft, sealing surfaces 26 of the aligned seal grooves 22,24. For
example, in one embodiment, the pressure loading may be due to the
pressurized compressor discharge air flowing from the compressor of
a gas turbine.
[0028] The spring member 20 of the spring loaded seal assembly 10
may generally comprise a separate, backing strip of material
configured to provide a spring seating force or spring loading
against the turbine seal 18. As shown in FIG. 2, the spring member
20 may generally extend longitudinally along at least a portion of
the length of the turbine seal 18. Additionally, in one embodiment,
the spring member 20 may comprise a strip of metal having a
substantially high yield strength so as to permit the spring member
20 to be spring loaded as it is flexed, bowed or bent against the
turbine seal 18 or against the seal grooves 22,24 of the adjacent
turbine components 14,16. For example, the spring member 20 may be
bowed along its length so as to apply a biasing force or load
against an adjacently disposed turbine seal 18 and, thereby,
maintain the seal 18 in sealing engagement with the adjacent
turbine components 14,16. Thus, in one embodiment, the spring
member 20 may comprise an elongated strip of spring steel bowed
along its length and having a rectangular cross-section. For
instance, the strip of spring steel may be configured as a leaf
spring to permit the spring member 20 to be loaded as it is flexed
or bowed into an arcuate shape. As used herein, the term leaf
spring may include a leaf spring having a single leaf or a leaf
spring having multiple leaves, such as two or more leaves. However,
it should be appreciated that the spring member 20 may comprise
various other flexible materials capable of being bent, bowed,
arced and/or flexed so as to provide loading on an adjacently
disposed turbine seal 18.
[0029] As indicated above, the spring member 20 may be configured
to maintain the turbine seal 18 in sealing engagement with the
adjacent turbine components 14,16. Thus, in one embodiment, the
spring member 20 may maintain the seal 18 in sealing engagement
with the sealing surfaces 26 of the turbine components 14,16 by
applying a spring seating or biasing force on and/or against the
high pressure side 28 of the turbine seal 18. This spring seating
force may be due, at least in part, to the mounting configuration
of the spring member 20. For example, the spring member 20 may be
mounted with respect to the turbine components 14,16 and/or the
turbine seal 18 such that it is bowed, bent, arced and/or flexed
into biased engagement with the turbine components 14,16 and/or the
turbine seal 18. Thus, as a result of this mounting configuration,
the spring member 20 may be adapted to apply an even load along the
length of the turbine seal 18 (particularly at the interface of the
turbine seal 18 and the corners 30 of the turbine components 14,16)
to maintain the turbine seal 18 in sealing engagement with the
adjacent turbine components 14,16. Additionally, one of ordinary
skill in the art should appreciate that, in alternative
embodiments, the spring member 20 may be selectively mounted at any
location along the turbine seal 18, such as at the corners 30, so
as to locally provide a seating force on or against the turbine
seal 18.
[0030] It should be appreciated that various suitable mounting
configurations may be used within the scope of the present subject
matter to sufficiently bow/bend/arc/flex or otherwise spring load
the spring member 20 such that it applies a spring seating force on
or against the turbine seal 18. One embodiment of a spring member
20 and suitable mounting configuration is illustrated in FIGS. 1-3.
As shown, the spring member 20 may comprise an elongated strip of
material having a width 31 less than the width of the gap 12
defined between the adjacent turbine components 14,16. This
narrower width 31 permits the spring member 20 to be mounted
exterior of the seal grooves 22,24 and thereby provides significant
flexibility with regard to the design of the spring loaded seal
assembly 10, such as by allowing a wider range of spacing between
the turbine seal 18 and the locations at which the spring member 20
is mounted. Moreover, such exterior mounting allows for smaller
seal grooves 22,24, which may provide for less leakage area and
better sealing.
[0031] Referring to FIGS. 1-3, the spring member 20 may comprise a
first end 32 and a second end 34. As shown, the first end 32 may be
generally configured to be mounted between the first and second
turbine components 14,16. For example, the first and second turbine
components 14,16 may define substantially aligned spring grooves 36
configured to slidably receive the first end 32 of the spring
member 20. Similarly, the first end 32 of the spring member 20 may
include an outwardly extending projection 38 configured to fit
within and engage the spring grooves 36. As such, the spring member
20 may be secured between the turbine components 14,16 by sliding
the projection 38 of the first end 32 into the spring grooves 36 of
the turbine components 14,16. However, it should be appreciated
that the first end 32 of the spring member 20 may be mounted or
otherwise secured to the first and second turbine components 14,16
or any other turbine component by any suitable means known in the
art. For example, the spring member 20 may be welded between the
first and second turbine components 14,16 or secured to a mounting
device attached to one or both of turbine components 14,16 or to
another turbine component. In a further embodiment, the projection
38 may be slidably mounted within the aligned seal grooves 22,24 of
the adjacent turbine components 14,16.
[0032] The second end 34 of the spring member 20 may generally be
mounted and/or disposed in a position that permits the spring
member 20 to be bowed/bent/arced/flexed along its length so as to
maintain the turbine seal 18 in sealing engagement with the turbine
components 14,16. For example, in the embodiment illustrated in
FIGS. 1-3, the second end 34 of the spring member 20 may be
generally disposed adjacent to a seal mounting bracket 40, such as
between the seal mounting bracket 40 and a portion of the turbine
seal 18. One of ordinary skill in the art should appreciate that
the seal mounting bracket 40 may generally be configured to mount
the turbine seal 18 to a third turbine component 42, such as the
turbine casing of a turbine assembly. Thus, referring to FIG. 3,
the spring member 20 may be loaded or bent/bowed/arced/flexed as
the mounting bracket 40 is installed over a mounting tab 44 of the
turbine seal 18 and secured to the third turbine component 42. As a
result of this loading, the spring member 20 may provide a spring
seating force across at least a portion of the turbine seal 18,
including loading at the corners 30 of the turbine components
14,16. It should be appreciated, however, that the second end 34 of
the spring member 20 need not be mounted and/or disposed adjacent
to the seal mounting bracket 40 but may generally be mounted and/or
disposed at any location that enables sufficient spring loading to
be applied to the turbine seal 18.
[0033] It should also be appreciated that, in alternative
embodiments, the spring member 20 may be mounted within the aligned
spring grooves 36 so as to contact the turbine seal 18 at multiple
locations along its length. For example, FIG. 10 illustrates a
modification of the embodiment of the spring loaded seal assembly
10 depicted in FIGS. 1-3. As shown, the spring member 20 may
include multiple projections 38 disposed along its length, with the
spring member 20 being bowed between each projection 38. Thus, the
spring member 20 may be configured to provide a force or spring
loading against the turbine seal 18 at multiple locations along the
length of the seal 18. Each projection 38 may be configured to fit
within and engage the aligned spring grooves 36. As such, the
spring member 20 may be secured between the turbine components
14,16 by sliding each of the projections 38 into the spring grooves
36 of the turbine components 14,16. In one embodiment, an end cap
39 may be disposed at the top of each spring groove 36, such as by
weld-filling the tops of the spring grooves 36, to ensure that the
spring member 20 remains in place. One of ordinary skill in the art
should appreciate that the spacing between the projections 38 may
be chosen such that the spring member 20 is sufficiently bowed
against the turbine seal 18 between each projection 38.
[0034] Referring now to FIGS. 4 and 5, another embodiment of a
spring loaded seal assembly 10 is illustrated in accordance with an
aspect of the present subject matter. Generally, the seal assembly
10 may include a turbine seal 18 and a spring member 20. As
particularly shown in FIG. 4, the spring member 20 of the seal
assembly 10 may generally comprise an elongated strip of material
including a substantially horizontal segment 46 attached to the
pressure side 28 of the turbine seal 18 and first and second arms
48,49 extending from the horizontal segment 46.
[0035] The horizontal segment 46 may generally be disposed
lengthwise and coplanar with the turbine seal 18 so as to extend
longitudinally along the length of the turbine seal 18.
Additionally, the horizontal segment 46 may be secured to the
turbine seal 18 by any suitable means known in the art, such as by
welding, riveting, screws, bolts, and the like. The first and
second arms 48,49 of the spring member 20 may generally extend away
from the horizontal segment 46, such as at an angle. For example,
as shown in FIG. 5, the arms 48,49 may extend away from the
horizontal segment 46 at an acute angle. Additionally, it should be
appreciated that the horizontal segment 46 and the arms 48,49 may
be formed from a single strip of material, such as by folding over
the sides of the material to form the angled arms 48,49 of the
spring member 20.
[0036] As indicated above, the spring member 20 may be formed from
a flexible, resilient material, such as spring steel. Thus, the
arms 48,49 of the spring member 20 may be configured to be flexed
or bent as the spring loaded seal assembly 10 is installed between
the seal grooves 22,24 of adjacent turbine components 14,16. For
example, as shown in FIG. 5, the resilient arms 48,49 may have a
particular length and/or may be disposed at particular angle with
respect to the horizontal segment 46 such that the arms 48,49 must
be flexed, bent inwards or otherwise compressed (i.e. making the
angle between the arms and the horizontal segment smaller) as the
spring loaded seal assembly 10 is installed. As such, the arms 48,
49 of the spring member 20 may be biased against the pressure or
forward surface 27 of the seal grooves 22,24. This bias against the
forward surface 27 allows the spring member 20 to apply a force or
spring loading against the turbine seal 18 in order to maintain the
seal in sealing engagement with the aft sealing surfaces 26 of the
seal grooves 22,24.
[0037] Referring now to FIG. 6, a further embodiment of a spring
loaded seal assembly 10 is illustrated in accordance with an aspect
of the present subject matter. Generally, the seal assembly 10
includes a turbine seal 18 and a spring member 20 As shown, the
spring member 20 may comprise an elongated strip of bowed or arced
material extending longitudinally along the length of the turbine
seal 18. In one embodiment, the spring member 20 may comprise a
strip of spring steel bowed along its length and configured as a
leaf spring. As such, the spring member 20 may be configured to
apply a force or load on the turbine seal 18 as the seal assembly
10 is installed between adjacent turbine components 14,16. For
example, the ends 52 of the spring member 20 may be attached or
secured to the turbine seal 18 such that a middle portion 54 of the
spring member 20 is bowed concavely with respect to the pressure
side 28 of the turbine seal 18. It should be appreciated that the
ends 52 may be attached to the turbine seal 18 by any suitable
means known in the art, such as by welding, riveting, bolts,
screws, and the like.
[0038] Additionally, the spring member 20 may generally have a
width greater than the width of the fluid leakage gap 12 (FIGS. 1
and 5) defined between the adjacent turbine components 14,16. Thus,
when the seal assembly 10 is installed, the spring member 20
extends between the seal grooves 22,24 and is biased and/or bowed
against the pressure or forward surface 27 (FIG. 5) of the seal
grooves 22,24. Specifically, the concave middle portion 54 of the
spring member 20 may be compressed within the seal grooves 22,24
due to the height of the arc/bow of the middle portion 54 in
relation to the size of the seal grooves 22,24. This compression
allows the spring member 20 to apply a force or spring loading
against the turbine seal 18, which thereby maintains the seal 18 in
sealing engagement with the aft sealing surfaces 26 of the seal
grooves 22,24.
[0039] Still another embodiment of a spring loaded seal assembly 10
is illustrated in FIG. 7. The spring loaded seal assembly 10
generally includes a turbine seal 18 and a spring member 20. As
shown, the spring member 20 may comprise a separate, elongated
strip of bowed or arced material extending longitudinally along the
length of the turbine seal 18. In one embodiment, the spring member
20 may comprise a strip of spring steel bowed along its length and
configured as a leaf spring. As such, the spring member 20 may be
configured to apply a force or load on the turbine seal 18 as the
seal assembly 10 is installed in between adjacent turbine
components 14,16. For example, the middle portion 54 of the spring
member 20 may be attached or secured to the turbine seal 18, with
the ends 52 of spring member 20 being bowed convexly with respect
to the pressure side 28 of the turbine seal 18. It should be
appreciated that the middle portion 54 may be attached to the
turbine seal 18 by any suitable means known in the art, such as by
welding, riveting, bolts, screws, and the like.
[0040] Additionally, the spring member 20 may generally have a
width greater than the width of the fluid leakage gap 12 (FIGS. 1
and 5) defined between the adjacent turbine components 14,16. Thus,
when the seal assembly 10 is installed, the spring member 20
extends between the seal grooves 22,24 and is biased and/or bowed
against the pressure or forward surface 27 (FIG. 5) of the seal
grooves 22,24. Specifically, the ends 52 of the spring member 20
may be compressed within the seal grooves 22,24 due to the height
of the arc/bow of the ends in relation to the size of the seal
grooves 22,24. This compression permits the spring member 20 to
apply a force or spring loading against the turbine seal 18, which
thereby maintains the seal 18 in sealing engagement with the aft
sealing surfaces 26 of the seal grooves 22,24.
[0041] It should also be appreciated that, in alternative
embodiments, the spring loaded seal assembly 10 may include more
than one spring member 20. For example, a plurality of spring
members 20 may be disposed along the length of the turbine seal 18.
For instance, FIG. 8 illustrates a modification of the embodiment
of the spring loaded seal assembly 10 depicted in FIGS. 4 and 5. As
shown, the spring member 20 is segmented along its length so as to
form a plurality of individual spring members 20. Accordingly,
similar to that described above in reference to FIG. 5, the arms
48, 49 of each spring member 20 may be biased against the pressure
or forward surface 27 (FIG. 5) of the seal grooves 22,24 so as to
apply a force or spring loading against the turbine seal 18 in
order to maintain the seal 18 in sealing engagement with the aft
sealing surfaces 26 of the seal grooves 22,24.
[0042] Additionally, it should be appreciated that the spring
member 20 may be segmented so as to form separate segments within a
single spring member 20. For example, a modification of the
embodiment of FIG. 6 is illustrated in FIG. 9. As shown, the spring
member 20 is secured to the turbine seal 18 at both its ends 52 and
at its middle portion 54, such as by welding, riveting, screws,
bolts, or the like. Thus, the spring member 20 is segmented into
two, concavely bowed segments 55 extending between each end 52 and
the middle portion 54 of the spring member 20. It should be
appreciated, however, that any number of segments 55 may be formed
in the spring member 20 and, thus, the number of segments 44 need
not be limited to two. As such, the concave segments 55 of the
spring member 20 may be compressed within the seal grooves 22,24 as
the spring loaded seal assembly 10 is installed between adjacent
turbine components 14,16. This compression allows the spring member
20 to apply a force or spring loading against the turbine seal 18,
which thereby maintains the seal 18 in sealing engagement with the
aft sealing surfaces 26 of the seal grooves 22,24.
[0043] This written description uses examples to disclose the
invention, including the best mode, and also to enable any person
skilled in the art to practice the invention, including making and
using any devices or systems and performing any incorporated
methods. The patentable scope of the invention is defined by the
claims, and may include other examples that occur to those skilled
in the art. Such other examples are intended to be within the scope
of the claims if they include structural elements that do not
differ from the literal language of the claims, or if they include
equivalent structural elements with insubstantial differences from
the literal language of the claims.
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