U.S. patent application number 12/872901 was filed with the patent office on 2012-03-01 for turbine blade assembly.
This patent application is currently assigned to GENERAL ELECTRIC COMPANY. Invention is credited to Robert Alan Brittingham, Andres Jose Garcia-Crespo.
Application Number | 20120051924 12/872901 |
Document ID | / |
Family ID | 45566316 |
Filed Date | 2012-03-01 |
United States Patent
Application |
20120051924 |
Kind Code |
A1 |
Garcia-Crespo; Andres Jose ;
et al. |
March 1, 2012 |
Turbine Blade Assembly
Abstract
A blade assembly for a rotor includes an attachment section
operably connectable to a rotor, and an airfoil section. At least
one retainer extends in a substantially tangential direction at
least partially through the airfoil section and the attachment
section to secure the airfoil section to the attachment section. A
method of assembling a rotor assembly includes inserting at least
one retainer in a substantially tangential direction at least
partially through an attachment section of a blade assembly and an
airfoil section of the blade assembly, thereby securing the airfoil
section to the attachment section. The blade assembly is then
secured to a rotor.
Inventors: |
Garcia-Crespo; Andres Jose;
(Greenville, SC) ; Brittingham; Robert Alan;
(Piedmont, SC) |
Assignee: |
GENERAL ELECTRIC COMPANY
Schenectady
NY
|
Family ID: |
45566316 |
Appl. No.: |
12/872901 |
Filed: |
August 31, 2010 |
Current U.S.
Class: |
416/221 ;
29/889.21 |
Current CPC
Class: |
F01D 5/147 20130101;
F05D 2230/64 20130101; F05D 2230/61 20130101; Y10T 29/49321
20150115 |
Class at
Publication: |
416/221 ;
29/889.21 |
International
Class: |
F01D 5/30 20060101
F01D005/30; B21K 25/00 20060101 B21K025/00 |
Goverment Interests
[0001] The subject invention was conceived under United States
Government contract DE-FC26-05NT42643-DOE. The Federal Government
may have certain rights to this invention.
Claims
1. A blade assembly for a rotor comprising: an attachment section
operably connectable to a rotor; an airfoil section; and at least
one retainer extending in a substantially tangential direction at
least partially through the airfoil section and the attachment
section to secure the airfoil section to the attachment
section.
2. The blade assembly of claim 1, wherein the at least one retainer
is at least one pin.
3. The blade assembly of claim 2, wherein the at least one pin is
secured in the blade assembly via welding.
4. The blade assembly of claim 1, wherein the attachment section
comprises a pocket into which the airfoil section is inserted.
5. The blade assembly of claim 4, wherein the pocket includes at
least one pocket hole into which the at least one retainer is
inserted.
6. The blade assembly of claim 5, wherein the at least one pocket
hole is disposed at one tangential surface of the pocket.
7. The blade assembly of claim 1, further comprising a bushing
disposed between the retainer and the airfoil section.
8. The blade assembly of claim 1, further comprising a sleeve
disposed between the airfoil section and the attachment
section.
9. The blade assembly of claim 1, wherein the airfoil section and
the attachment section are formed of different materials.
10. The blade assembly of claim 1 wherein the airfoil section is
formed of a ceramic matrix composite and/or a single crystal
alloy.
11. The blade assembly of claim 1, wherein the attachment section
is formed of a nickel alloy.
12. The blade assembly of claim 1, wherein the attachment section
is operably connectable to the rotor via an axially-extending
dovetail.
13. A method of assembling a rotor assembly comprising: inserting
at least one retainer in a substantially tangential direction at
least partially through an attachment section of a blade assembly
and an airfoil section of the blade assembly, thereby securing the
airfoil section to the attachment section; and securing the blade
assembly to a rotor.
14. The method of claim 13, further comprising inserting the
airfoil section into a pocket of the attachment section.
15. The method of claim 13, further comprising disposing a bushing
between the at least one retainer and the airfoil section.
16. The method of claim 13, further comprising disposing a sleeve
between the airfoil section and the attachment section.
17. The method of claim 13, wherein the at least one retainer is at
least one pin.
18. The method of claim 17, further comprising securing the at
least one pin in the blade assembly via welding.
19. The method of claim 13, further comprising securing additional
blade assemblies to the rotor.
20. The method of claim 19, further comprising retaining the at
least one retainer in the blade assembly via contact of the at
least one retainer with an adjacent blade assembly.
Description
BACKGROUND OF THE INVENTION
[0002] The subject matter disclosed herein relates to
turbomachines. More specifically, the subject disclosure relates to
turbine blade assemblies for turbomachines.
[0003] Turbine assemblies include a number of blades secured to a
rotor. In some turbines, it is desirable for the blade to include
an airfoil portion and a platform portion into which the airfoil
portion is inserted, often in order to allow the airfoil portion
and the platform portion to be formed from different materials. The
combined airfoil/platform blade assembly is secured to the rotor
via, for example, a conventional dovetail attachment.
[0004] Blade assemblies where the airfoil portion and the platform
portion are of differing materials having differing mechanical and
thermal characteristics that introduce thermal matching problems as
well as issues regarding the mechanical integrity of the assembly.
In such assemblies the airfoil portions are typically secured to
the platform portions also via dovetails, often in an axial
direction. This introduces leakage paths through the turbomachine,
for which additional sealing structures must be introduced to
control the leakage. As such, the part count and therefore cost of
the turbomachine increases. The art would well receive a turbine
blade assembly that is cost effective and does not greatly
negatively impact leakage through the turbomachine.
BRIEF DESCRIPTION OF THE INVENTION
[0005] According to one aspect of the invention, a blade assembly
for a rotor includes an attachment section operably connectable to
a rotor, and an airfoil section. At least one retainer extends in a
substantially tangential direction at least partially through the
airfoil section and the attachment section to secure the airfoil
section to the attachment section.
[0006] According to another aspect of the invention, a method of
assembling a rotor assembly includes inserting at least one
retainer in a substantially tangential direction at least partially
through an attachment section of a blade assembly and an airfoil
section of the blade assembly, thereby securing the airfoil section
to the attachment section. The blade assembly is then secured to a
rotor.
[0007] These and other advantages and features will become more
apparent from the following description taken in conjunction with
the drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] The subject matter, which is regarded as the invention, is
particularly pointed out and distinctly claimed in the claims at
the conclusion of the specification. The foregoing and other
features, and advantages of the invention are apparent from the
following detailed description taken in conjunction with the
accompanying drawings in which:
[0009] FIG. 1 is a partial plan view of an embodiment of a rotor
assembly;
[0010] FIG. 2 is an exploded view of an embodiment of a blade
assembly for a rotor assembly; and
[0011] FIG. 3 is a cross-sectional view of an embodiment of a blade
assembly for a rotor assembly.
[0012] The detailed description explains embodiments of the
invention, together with advantages and features, by way of example
with reference to the drawings.
DETAILED DESCRIPTION OF THE INVENTION
[0013] Shown in FIG. 1 is an embodiment of a rotor assembly 10 for,
for example, a turbine of a turbomachine. The rotor assembly 10
includes a plurality of blade assemblies 12 secured to a rotor 14
at a periphery of the rotor 14 via, for example, a plurality of
dovetail attachments 16.
[0014] Referring to the exploded view of FIG. 2, a blade assembly
12 includes an airfoil section 18 and an attachment section 20. The
airfoil section 18 includes an airfoil 22 and, in some embodiments,
a platform 24 which defines an annular flowpath of the rotor 14.
The airfoil section 18 may be formed from a variety of materials,
which are well suited to the high temperature environment in which
many rotors 14 operate. For example, the airfoil section 18 may be
formed from a ceramic matrix composite (CMC), or a single crystal
alloy. The attachment section 20 is formed separately from the
airfoil section 18 and may be formed from a material different than
that utilized in the airfoil section 18. Since the environment of
the attachment section 20 is not as high temperature as that of the
airfoil section 18, lower cost metallic materials such as nickel
alloys may be used. The attachment section 20 includes an
attachment feature to secure the blade assembly to the rotor 14,
which in some embodiments is the dovetail 16.
[0015] The attachment section 20 includes a web portion 26, which
in some embodiments, extends in a substantially axial direction
along the attachment section 20. The web portion 26 includes a
pocket 28 into which a tab 30 of the airfoil section 18 is
inserted. The pocket 28 includes one or more pocket holes 32
through at least one wall of the pocket 28. As shown in FIG. 2, in
some embodiments the pocket hole 32 extends through an
axially-extending sidewall 34 of the pocket 28. Although the
embodiment of FIG. 2 includes one pocket hole 32, it is to be
appreciated that two or more pocket holes 32 may be included. The
tab 30 includes at least one tab hole 36 extending therethrough and
substantially aligned with the one or more pocket holes 32. While
the tab hole 36 and the pocket hole 32 shown in FIG. 2 are round,
it is to be appreciated that the tab hole 36 and/or the pocket hole
32 may be other shapes, for example oval or angular.
[0016] One or more retainers, for example, blade pins 38 are
included to secure the airfoil section 18 to the attachment section
20. Each blade pin 38 extends tangentially through the pocket hole
32 and at least partially through the tab hole 36. Referring now to
FIG. 3, the blade pin 38 extends through the pocket hole 32 at a
first sidewall 34 of the pocket 28 and through the tab hole 36. In
this embodiment, a second sidewall 34 of the pocket is without a
pocket hole 32 so that a tip 40 of the blade pin 38 does not pass
entirely through the pocket 28. To prevent the blade pin 38 from
being inadvertently removed, when the adjacent blade assembly 12 is
installed in the rotor 14, the sidewall 34 of the adjacent blade
assembly 12 may substantially abut a head 42 of the blade pin 38 to
retain the blade pin 38 in the blade assembly 12. In other
embodiments, the blade pin may be retained in the blade assembly 12
via a process such as welding, or other retention means. Further,
the blade pin 38 may be assembled to the blade assembly 12 via a
press fit. Even though a blade pin 38 is utilized in the
illustrated embodiment of FIG. 3, it is to be appreciated that
other means for securing the airfoil section 18 to the attachment
section 20, including mechanical threaded fasteners, wedges,
welding, and/or adhesives.
[0017] Referring again to FIG. 2, in some embodiments, the blade
assembly 12 includes a bushing 44 installed into the pocket holes
32 and tab holes 36 prior to installing the blade pin 38. Use of
the bushing 44 reduces hertz stresses on the blade assembly 12 in
the area of the blade pin 38. As shown in FIGS. 2 and 3, a sleeve
46, comprising for example, a relatively soft material, is disposed
between the tab 30 and the pocket 28. The sleeve 46 is utilized to
reduce stresses and wear on the tab 30 and the pocket 28 at the
interfaces between the tab 30 and the pocket 28.
[0018] While the invention has been described in detail in
connection with only a limited number of embodiments, it should be
readily understood that the invention is not limited to such
disclosed embodiments. Rather, the invention can be modified to
incorporate any number of variations, alterations, substitutions or
equivalent arrangements not heretofore described, but which are
commensurate with the spirit and scope of the invention.
Additionally, while various embodiments of the invention have been
described, it is to be understood that aspects of the invention may
include only some of the described embodiments. Accordingly, the
invention is not to be seen as limited by the foregoing
description, but is only limited by the scope of the appended
claims.
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