U.S. patent number 10,385,701 [Application Number 14/844,317] was granted by the patent office on 2019-08-20 for damper pin for a turbine blade.
This patent grant is currently assigned to GENERAL ELECTRIC COMPANY. The grantee listed for this patent is General Electric Company. Invention is credited to Ariel Caesar Prepena Jacala, Spencer A. Kareff, Brian Denver Potter.
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United States Patent |
10,385,701 |
Kareff , et al. |
August 20, 2019 |
Damper pin for a turbine blade
Abstract
A damper pin for damping adjacent turbine blades coupled to a
rotor shaft includes a first end portion that is axially spaced
from a second end portion and a spring member that extends axially
from an inner surface of the first end portion to an inner surface
of the second end portion. The first end portion, the spring member
and the second end portion define a generally arcuate top portion
of the damper pin. The top portion is configured to contact with a
groove defined between the adjacent turbine blades.
Inventors: |
Kareff; Spencer A.
(Simpsonville, SC), Potter; Brian Denver (Greer, SC),
Jacala; Ariel Caesar Prepena (Travelers Rest, SC) |
Applicant: |
Name |
City |
State |
Country |
Type |
General Electric Company |
Schenectady |
NY |
US |
|
|
Assignee: |
GENERAL ELECTRIC COMPANY
(Schenectady, NY)
|
Family
ID: |
56740151 |
Appl.
No.: |
14/844,317 |
Filed: |
September 3, 2015 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20170067348 A1 |
Mar 9, 2017 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F01D
5/22 (20130101); F05D 2250/25 (20130101); Y02T
50/60 (20130101); F05D 2220/32 (20130101); Y02T
50/673 (20130101); Y02T 50/671 (20130101) |
Current International
Class: |
F01D
5/22 (20060101) |
Field of
Search: |
;416/145,190 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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2 472 065 |
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Jul 2012 |
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EP |
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2 738 353 |
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Jun 2014 |
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EP |
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3 043 085 |
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Jul 2016 |
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EP |
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3 070 274 |
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Sep 2016 |
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EP |
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3 078 808 |
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Oct 2016 |
|
EP |
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3 093 439 |
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Nov 2016 |
|
EP |
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Other References
Co-Pending U.S. Appl. No. 14/844,280, filed Sep. 3, 2015. cited by
applicant .
Co-Pending U.S. Appl. No. 14/844,294, filed Sep. 3, 2015. cited by
applicant .
Co-Pending U.S. Appl. No. 14/844,306, filed Sep. 3, 2015. cited by
applicant .
Co-Pending U.S. Appl. No, 14/844,392, filed Sep. 3, 2015. cited by
applicant .
Co-Pending U.S. Appl. No. 14/988,070, filed Jan. 5, 2016. cited by
applicant .
Co-Pending U.S. Appl. No. 14/844,545, filed Sep. 3, 2015. cited by
applicant .
Extended European Search Report and Opinion issued in connection
with related EP Application No. 16185251.2 dated Jan. 31, 2017.
cited by applicant .
Extended European Search Report and Opinion issued in connection
with related EP Application No. 16183857.8 dated Feb. 3, 2017.
cited by applicant .
Extended European Search Report and Opinion issued in connection
with related EP Application No. 16186535.7 dated Feb. 3, 2017.
cited by applicant .
Extended European Search Report and Opinion issued in connection
with related EP Application No. 16183856.0 dated Feb. 3, 2017.
cited by applicant .
Extended European Search Report and Opinion issued in connection
with corresponding EP Application No. 16184881.7 dated Feb. 3,
2017. cited by applicant .
Extended European Search Report and Opinion issued in connection
with related EP Application No. 16185255.3 dated Feb. 3, 2017.
cited by applicant .
Non-Final Rejection towards related U.S. Appl. No. 14/844,294 dated
Mar. 23, 2017. cited by applicant .
Final Rejection towards related U.S. Appl. No. 14/844,294 dated
Jul. 24, 2017. cited by applicant.
|
Primary Examiner: Laurenzi; Mark A
Assistant Examiner: Thiede; Paul W
Attorney, Agent or Firm: Dority & Manning, P.A.
Claims
What is claimed is:
1. A damper pin for damping adjacent turbine blades coupled to a
rotor shaft, the damper pin comprising: a first end portion axially
aligned with and axially spaced from a second end portion; a spring
member that extends axially from an inner surface of the first end
portion to an inner surface of the second end portion, wherein the
first end portion, the spring member and the second end portion
define a generally arcuate top portion of the damper pin configured
to contact with a groove defined between the adjacent turbine
blades, a retention pin coaxially aligned with and disposed between
the first end portion and the second end portion, wherein the
spring member extends circumferentially around the retention pin,
and wherein the retention pin is seated within an opening defined
by the first end portion or the second end portion.
2. The damper pin as in claim 1, wherein the spring member is
helical shaped.
3. The damper pin as in claim 1, wherein the spring member is
connected to at least one of the inner surface of the first end
portion or the inner surface of the second end portion.
4. The damper pin as in claim 1, wherein the spring member
comprises a first spring coaxially aligned with a second
spring.
5. The damper pin as in claim 4, wherein the first spring is
connected at one end to the first end portion and the second spring
is connected at one to the second end portion.
6. The damper pin as in claim 1, wherein a portion of the first end
portion is semi-cylindrical.
7. The damper pin as in claim 1, wherein a portion of the second
end portion is semi-cylindrical.
8. A turbine engine, comprising: a rotor shaft that extends axially
within the turbine engine; an adjacent pair of turbine blades
coupled to the rotor shaft, each turbine blade at least partially
defining a groove that extends along a slash face of the
corresponding turbine blade; and a damper pin disposed within the
groove, the damper pin comprising: a first end portion axially
aligned with and axially spaced from a second end portion; a spring
member that extends axially from an inner surface of the first end
portion to an inner surface of the second end portion, wherein the
first end portion, the spring member and the second end portion
define a generally arcuate top portion of the damper pin configured
to contact with the groove defined between the adjacent turbine
blades, a retention pin coaxially aligned with and disposed between
the first end portion and the second end portion, wherein the
spring member extends circumferentially around the retention pin,
and wherein the retention pin is seated within an opening defined
by the first end portion or the second end portion.
9. The turbine engine as in claim 8, wherein the spring member is
helical shaped.
10. The turbine engine as in claim 8, wherein the spring member is
connected to at least one of the inner surface of the first end
portion or the inner surface of the second end portion.
11. The turbine engine as in claim 8, wherein the spring member
comprises a first spring coaxially aligned with a second
spring.
12. The turbine engine as in claim 11, wherein the first spring is
connected at one end to the first end portion and the second spring
is connected at one to the second end portion.
13. The turbine engine as in claim 8, wherein a portion of the
first end portion is semi-cylindrical.
14. The turbine engine as in claim 8, wherein a portion of the
second end portion is semi-cylindrical.
Description
FIELD OF THE INVENTION
The present invention generally relates to a turbomachine having
multiple circumferentially aligned turbine blades. More
particularly, this invention involves a damper pin having a spring
member for providing vibration damping between adjacent turbine
blades.
BACKGROUND OF THE INVENTION
A turbine blade, also known as a turbine bucket or turbine rotor
blade, converts energy from a flowing fluid such as hot combustion
gas or steam into mechanical energy by causing a rotor shaft of a
turbomachine to rotate. As the turbomachine transitions through
various operating modes, the turbine blades are subjected to both
mechanical and thermal stresses.
A turbine blade generally includes an airfoil that extends radially
outwardly from a platform, a shank that extends radially inwardly
from the platform and a dovetail or mounting portion that extends
radially inwardly from the shank. The dovetail of each turbine
blade is secured within a complementary slot defined in a rotor
wheel or disk. The rotor wheel is coupled to the rotor shaft.
During engine operation, vibrations may be introduced into the
turbine blades. For example, fluctuations in flow of the hot
combustion gases or steam may cause them to vibrate. One basic
design consideration for turbomachine designers is to avoid or to
minimize resonance with natural frequencies of the turbine blades
and the dynamic stresses produced by forced response and/or
aero-elastic instabilities, thus controlling high cycle fatigue of
the turbine blades. In order to improve the high cycle fatigue life
of a turbine blade, vibration dampers are typically provided below
and/or between the platforms to frictionally dissipate vibratory
energy and reduce the corresponding amplitude of vibration during
operation. The amount of vibrational energy that is removed by the
vibration damper is a function of the dynamic weight of the
vibration damper and the reaction loads.
Although known dampers may be largely adequate during typical
operations, there is a desire to improve overall damper
effectiveness. Prior attempts to accomplish damping of vibrations
have included round damper pins, sheet metal flat dampers, or
complex wedge shaped dampers. Often true damper performance of
these types of dampers is not known until the first engine test.
However, at that time, the damper pocket geometry in the turbine
blades is locked in by hard tooling. Thus, if the damper does not
perform as expected, then a potentially expensive tooling rework
may be required. Accordingly, there is desire for a damping pin
that provides a natural frequency tuning tool for resonant mode
excitation avoidance and that enables independent mode tuning
options without necessitating changes to the design of an existing
turbine blade.
BRIEF DESCRIPTION OF THE INVENTION
Aspects and advantages of the invention are set forth below in the
following description, or may be obvious from the description, or
may be learned through practice of the invention.
One embodiment of the present invention is a damper pin for damping
adjacent turbine blades coupled to a rotor shaft. The damper pin
includes a first end portion that is axially spaced from a second
end portion and a spring member that extends axially from an inner
surface of the first end portion to an inner surface of the second
end portion. The first end portion, the spring member and the
second end portion define a generally arcuate top portion of the
damper pin. The top portion is configured to contact with a groove
defined between the adjacent turbine blades.
Another embodiment of the present invention is a turbine engine.
The turbine engine includes a rotor shaft that extends axially
within the turbine engine and an adjacent pair of turbine blades
that are coupled to the rotor shaft. Each turbine blade at least
partially defines a groove that extends along a slash face of the
corresponding turbine blade. The turbine engine further includes a
damper pin that is disposed within the groove between the adjacent
turbine blades. The damper pin comprises a first end portion that
is axially spaced from a second end portion and a spring member
that extends axially from an inner surface of the first end portion
to an inner surface of the second end portion. The first end
portion, the spring member and the second end portion define a
generally arcuate top portion of the damper pin. The top portion is
configured to contact with the groove defined between the adjacent
turbine blades.
Those of ordinary skill in the art will better appreciate the
features and aspects of such embodiments, and others, upon review
of the specification.
BRIEF DESCRIPTION OF THE DRAWINGS
A full and enabling disclosure of the present invention, including
the best mode thereof to one skilled in the art, is set forth more
particularly in the remainder of the specification, including
reference to the accompanying figures, in which:
FIG. 1 illustrates a functional diagram of an exemplary gas turbine
as may incorporate at least one embodiment of the present
invention;
FIG. 2 is a perspective view of an exemplary turbine blade
according to at least one embodiment of the present invention;
FIG. 3 is a schematic illustration of a damper pin disposed between
circumferentially adjacent turbine blades according to at least one
embodiment of the present invention;
FIG. 4 is a side view of an exemplary damper pin according to one
embodiment of the present invention;
FIG. 5 is a top view of the exemplary damper pin as shown in FIG.
4; and
FIG. 6 is a cross sectioned side view of an exemplary damper pin
according to one embodiment of the present invention.
DETAILED DESCRIPTION OF THE INVENTION
Reference will now be made in detail to present embodiments of the
invention, one or more examples of which are illustrated in the
accompanying drawings. The detailed description uses numerical and
letter designations to refer to features in the drawings. Like or
similar designations in the drawings and description have been used
to refer to like or similar parts of the invention. As used herein,
the terms "first", "second", and "third" may be used
interchangeably to distinguish one component from another and are
not intended to signify location or importance of the individual
components.
The terms "upstream" and "downstream" refer to the relative
direction with respect to fluid flow in a fluid pathway. For
example, "upstream" refers to the direction from which the fluid
flows, and "downstream" refers to the direction to which the fluid
flows. The term "radially" refers to the relative direction that is
substantially perpendicular to an axial centerline of a particular
component, and the term "axially" refers to the relative direction
that is substantially parallel and/or coaxially aligned to an axial
centerline of a particular component.
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 modifications and variations can be
made in the present invention without departing from the scope or
spirit thereof. For instance, features illustrated or described as
part of one embodiment may be used on 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. Although an
industrial or land based gas turbine is shown and described herein,
the present invention as shown and described herein is not limited
to a land based and/or industrial gas turbine unless otherwise
specified in the claims. For example, the invention as described
herein may be used in any type of turbomachine including but not
limited to a steam turbine, an aircraft gas turbine or marine gas
turbine.
Referring now to the drawings, FIG. 1 illustrates a schematic
diagram of one embodiment of a gas turbine 10. The gas turbine 10
generally includes an inlet section 12, a compressor section 14
disposed downstream of the inlet section 12, a plurality of
combustors (not shown) within a combustor section 16 disposed
downstream of the compressor section 14, a turbine section 18
disposed downstream of the combustor section 16 and an exhaust
section 20 disposed downstream of the turbine section 18.
Additionally, the gas turbine 10 may include one or more shafts 22
coupled between the compressor section 14 and the turbine section
18.
The turbine section 18 may generally include a rotor shaft 24
having a plurality of rotor disks 26 (one of which is shown) and a
plurality of rotor blades 28 extending radially outwardly from and
being interconnected to the rotor disk 26. Each rotor disk 26 in
turn, may be coupled to a portion of the rotor shaft 24 that
extends through the turbine section 18. The turbine section 18
further includes an outer casing 30 that circumferentially
surrounds the rotor shaft 24 and the rotor blades 28, thereby at
least partially defining a hot gas path 32 through the turbine
section 18.
During operation, a working fluid such as air flows through the
inlet section 12 and into the compressor section 14 where the air
is progressively compressed, thus providing pressurized air to the
combustors of the combustion section 16. The pressurized air is
mixed with fuel and burned within each combustor to produce
combustion gases 34. The combustion gases 34 flow through the hot
gas path 32 from the combustor section 16 into the turbine section
18, wherein energy (kinetic and/or thermal) is transferred from the
combustion gases 34 to the rotor blades 28, thus causing the rotor
shaft 24 to rotate. The mechanical rotational energy may then be
used to power the compressor section 14 and/or to generate
electricity. The combustion gases 34 exiting the turbine section 18
may then be exhausted from the gas turbine 10 via the exhaust
section 20.
FIG. 2 illustrates a conventional turbine blade or bucket 28
including an airfoil 36, a platform 38, a shank 40 and a dovetail
or mounting portion 42. FIG. 3 provides a downstream view of a pair
of circumferentially adjacent turbine blades 28(a), 28(b). As shown
in FIG. 2, the dovetail 42 is utilized to secure the turbine blade
28 to a periphery of the rotor disk 26 (FIG. 1), as is well
understood in the art. The platform 38 defines an inward flow
boundary for the combustion gases 34 flowing through the hot gas
path 32 of the turbine section 18 (FIG. 1). In various embodiments
of the present invention, a damper pin 44 is located along one
axial edge (or slash face) 46 adjacent to (i.e., radially inward
of) the turbine blade platform 38. It will be appreciated that a
similar damper pin 44 is located between each adjacent pair of
turbine blades 28(a), 28(b) (FIG. 3) on the rotor disk 26 (FIG. 1)
as apparent from FIG. 3. In particular embodiments, as shown in
FIG. 2, the damper pin 44 is located in an elongated groove 48
(FIG. 1) that extends along the entire slash face 46 of the turbine
blade 28.
The damper pin 44 serves as a vibration damper. When installed, as
shown in FIG. 3, the damper pin 44 is positioned between the
adjacent turbine blades 28(a), 28(b). In operation, the damper pin
44 frictionally dissipates vibratory energy and reduces
corresponding amplitude of vibration. The amount of vibrational
energy that is removed by the damper pin 44 is a function several
factors including but not limited to the dynamic weight of the
damper pin 44, the geometry of the damper pin 44 and the reaction
loads between the adjacent turbine blades 28(a), 28(b).
FIG. 4 provides a side view of an exemplary damper pin 100
according to one embodiment of the present invention. FIG. 5
provides a top view of the damper pin 100 as shown in FIG. 4. It is
to be understood that damper pin 100 shown in FIG. 4 may be
substituted for damper pin 44 as shown in FIGS. 2 and 3.
In one embodiment, as shown collectively in FIGS. 4 and 5, the
damper pin 100 includes a first end portion 102 axially spaced from
a second end portion 104 with respect to an axial centerline 106 of
the damper pin 100. In particular embodiments, the first end
portion 102 and the second end portion 104 may be coaxially aligned
with respect to centerline 106.
As shown in FIGS. 4 and 5, the damper pin 100 further includes a
spring member 108 that extends axially from an inner surface 110 of
the first end portion 102 to an inner surface 112 of the second end
portion 104. The first end portion 102, the spring member 108 and
the second end portion 104 define a generally arcuate top portion
or surface 114 of the damper pin 100. The top portion 114 is
generally configured (shaped and/or sized) to contact with a
portion of the groove 48 defined between the adjacent turbine
blades 28(a), 28(b).
In particular embodiments, as shown collectively in FIGS. 4 and 5,
the first end portion 102 and/or the second end portion 104 of the
damper pin 100 are substantially semi-cylindrical. As shown in FIG.
4, the first end portion 102 and/or the second end portion 104 may
include shoulders 116, 118 respectfully. This configuration creates
flat support surfaces 120, 122 that are adapted to rest on machined
turbine blade platform surfaces or shoulders at opposite ends of
the groove 48 formed in the turbine blade slash face 46, thereby
providing support for the damper pin 100 while preventing
undesirable excessive rotation during machine operation.
In particular embodiments, as shown in FIG. 4, opposing ends 124,
126 of the spring member 108 may be fixedly connected to the first
end portion 102 and the second end portion 104 respectfully. In
particular embodiments, the opposing ends 124, 126 of the spring
member 108 may be engaged with or compressed against the inner
surface 110 of the first end portion 102 and/or the inner surface
112 of the second end portion 104.
In particular embodiments, as shown in FIGS. 4 and 5, the spring
member 108 is generally helical shaped. Although the spring member
is illustrated in the figures as a helical or coil type spring, it
is to be understood by one skilled in the art that the spring
member 108 may be any suitable type spring such as but not limited
to a wave spring or the like and that the invention is not limited
to a helical or coil type spring member unless otherwise provided
in the claims.
In particular embodiments, the spring member 108 may comprise of
multiple springs coaxially aligned and extending between the first
end portion 102 and the second end portion 104. For example, in one
embodiment, as shown in FIG. 5, the spring member 108 comprises a
first spring 128 coaxially aligned with a second spring 130. The
first spring 128 may be connected at one end 132 to the first end
portion 102 and the second spring 130 may be connected at one end
134 to the second end portion 104. The first and second springs
128, 130 may be engaged at contact point 136 that is defined
between the inner surface 110 of the first end portion 102 and the
inner surface 112 of the second end portion 104.
FIG. 6 is a cross sectional side view of an exemplary embodiment of
the damper pin 100 according to one embodiment of the present
invention. As shown in FIG. 6, the damper pin 100 may include a
retention pin 138. The retention pin 138 may be coaxially aligned
with and disposed between the first end portion 102 and the second
end portion 104. The spring member 108 extends circumferentially
around the retention pin 138. The retention pin 138 may be seated
within openings 140(a), 140(b) defined by the first end portion 102
and the second end portion 104 respectfully.
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.
* * * * *