Improved patch ring and method of using same

Abstract

Shaft assemblies, turbomachines, and methods of servicing turbomachines are provided. A shaft assembly includes a first shaft having a first notch annularly defined therein. The first notch includes a first axially extending face and a first radially extending face. A second shaft is coupled to the first shaft. The second shaft includes a second notch annularly defined therein and positioned opposite the first notch. The second notch includes a second axially extending face and a second radially extending face. A patch ring is mounted between the first notch and the second notch. The patch ring includes a body positioned between and in contact with the first axially extending face and the second axially extending face. A first arm extends radially outward from the body, and a second arm extends radially inward from the body.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to improved patch rings and related methods. In particular, the present disclosure relates to improved patch rings for turbine close coupled joints. BACKGROUND

[0002] Turbomachines are used in a variety of industries and applications for energy transfer purposes. For example, a gas turbine engine generally includes a compressor section, a combustion section, a turbine section, and an exhaust section. The compressor section progressively increases the pressure of a working fluid entering the gas turbine engine and supplies this compressed working fluid to the combustion section. The compressed working fluid and a fuel, such as natural gas, are mixed within the combustion section and combusted in a combustion chamber to generate high pressure and temperature combustion gases. The combustion gases flow from the combustion section into the turbine section where the combustion gases expand to do work. For example, the expansion of the combustion gases in the turbine section can cause a rotor shaft connected to, for example, an electrical generator to rotate to produce electricity. The combustion gases then exit the gas turbine via the exhaust section.

[0003] During operation of the turbomachine, various components of the turbomachine are subject to various forms of wear. Such wear can often result in damage and / or failure of individual components and the turbomachine. In particular, the compressor shaft and turbine shaft, which rotate during operation of the turbomachine, are susceptible to wear. For example, the compressor and turbine shafts of the present invention can be expected to run for approximately 144,000 hours and start 5,000 times. Furthermore, in many cases, particular wear sensitive locations on components, such as the notched flange, can tend to wear faster than other locations. These wear sensitive locations can limit the life of the associated compressor shaft and / or turbine shaft.

[0004] Defects in the compressor shaft and turbine shaft must be repaired so that they remain as intended. Currently, the compressor shaft and turbine shaft are repaired by post-operation machining on the contact surfaces defined between the shafts in order to restore the design specified interference between the two shafts. However, over multiple service intervals, machining the notched joint can adversely affect the required contact interference between the compressor shaft and turbine shaft.

[0005] Accordingly, there is a need in the art for improved methods and devices for repairing turbomachine joints. In particular, there is a need for improved methods and devices for repairing the notched joint between the compressor shaft and turbine shaft. SUMMARY

[0006] Aspects and advantages of the shaft assembly, turbomachine, and method of repairing a turbomachine according to the present disclosure will be set forth in part in the following description, or can be obvious from the description, or can be learned through practice of the technology.

[0007] According to one embodiment, a shaft assembly is provided. The assembly includes a first shaft having a first notch annularly defined therein. The first notch includes a first axially extending face and a first radially extending face. A second shaft is coupled to the first shaft. The second shaft includes a second notch annularly defined therein and positioned opposite the first notch. The second notch includes a second axially extending face and a second radially extending face. A patch ring is mounted between the first notch and the second notch. The patch ring includes a body positioned between and in contact with the first axially extending face and the second axially extending face. A first arm extends radially outward from the body and a second arm extends radially inward from the body.

[0008] According to another embodiment, a turbine is provided. The turbine includes a compressor section, a combustor section, and a turbine section. The turbine also includes a compressor shaft at least partially disposed in the compressor section. The compressor shaft has a first notch annularly defined therein. The first notch includes a first axially extending face and a first radially extending face. The turbine also includes a turbine shaft at least partially disposed in the turbine section and coupled to the compressor shaft. The turbine shaft has a second notch annularly defined therein and positioned opposite the first notch. The second notch includes a second axially extending face and a second radially extending face. A patch ring is mounted between the first notch and the second notch.

[0009] According to yet another embodiment, a method of servicing a turbine is provided. The method includes machining a first notch within a rear end of a compressor shaft. The first notch includes a first axially extending face and a first radially extending face. The first notch is annularly defined within the rear end of the compressor shaft. The method also includes machining a second notch within a forward end of a turbine shaft. The second notch includes a second axially extending face and a second radially extending face. The second notch is annularly defined within the forward end of the turbine shaft and positioned opposite the first notch. The method further includes mounting a patch ring between the first notch and the second notch.

[0010] These and other features, aspects, and advantages of the shaft assembly, turbine, and method of servicing a turbine of the present technology 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 technology and, together with the description, serve to explain the principles of the technology. BRIEF DESCRIPTION OF DRAWINGS

[0011] The complete and enabling disclosure of the shaft assembly, turbine, and method of servicing a turbine of the present technology, related to the ordinary skill in the art, is set forth in this specification which functions as a book of instructions in

[0012] Figure 1 is a schematic illustration of a turbine according to an embodiment of the present disclosure;

[0013] Figure 2 A cross-sectional view of a shaft assembly is shown prior to installation of a patch ring in accordance with an embodiment of the present disclosure;

[0014] Figure 3 A cross-sectional view of a shaft assembly is shown prior to installation of a patch ring in accordance with an embodiment of the present disclosure;

[0015] Figure 4 A cross-sectional view of a shaft assembly is shown prior to installation of a patch ring in accordance with an embodiment of the present disclosure;

[0016] Figure 5 A side view of a patch ring is shown in accordance with an embodiment of the present disclosure;

[0017] Figure 6 A side view of a patch ring is shown in accordance with an embodiment of the present disclosure; Figure 5 An enlarged perspective view of a patch ring is shown in accordance with an embodiment of the present disclosure;

[0018] Figure 7 A side view of a patch ring is shown in accordance with an embodiment of the present disclosure.

[0019] Figure 8 A side view of a patch ring is shown in accordance with an embodiment of the present disclosure. Figure 7 An enlarged perspective view of a patch ring is shown in accordance with an embodiment of the present disclosure;

[0020] Figure 9 A method of servicing a turbomachine is shown in accordance with an embodiment of the present disclosure. DETAILED DESCRIPTION

[0021] Reference will now be made in detail to embodiments of shaft assemblies, turbomachines, and methods of servicing turbomachines of the present application, examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the present technology, not limitation, of the present technology. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present technology without departing from the scope or spirit of the claimed technology. 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 this disclosure cover such modifications and variations as come within the scope of the appended claims and their equivalents.

[0022] 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 identify like or similar portions of the application. As used herein, the terms "first", "second", and "third" can be used interchangeably to distinguish one component from another and are not intended to signify location or importance of the individual components.

[0023] As used herein, the terms "upstream" (or "up") and "downstream" (or "down") refer to the relative direction with respect to the flow of fluid in a fluid pathway. For example, "upstream" refers to the direction from which fluid flows, and "downstream" refers to the direction to which fluid flows. The term "radially" refers to a relative direction substantially perpendicular to an axial centerline of a particular component, the term "axially" refers to a relative direction substantially parallel and / or coaxially aligned with an axial centerline of a particular component, and the term "circumferentially" refers to a relative direction extending around an axial centerline of a particular component. Approximating language, such as "generally" or "about," encompasses values that are within ten percent of a specified value. When used in the context of an angle or direction, such terminology encompasses angles or directions that are within ten degrees of the specified angle or direction. For example, "generally vertical" encompasses directions that are within ten degrees of vertical in any direction (e.g., clockwise or counterclockwise).

[0024] Referring now to the drawings, Figure 1 A partial cutaway view of one embodiment of a turbomachine, which in the illustrated embodiment is a gas turbine 10, is shown. Although an industrial or land-based gas turbine is shown and described herein, the present disclosure is not limited to land-based and / or industrial gas turbines unless otherwise specified in the claims. For example, the present invention as described herein can be used in any type of turbomachine, including but not limited to a steam turbine, an aircraft gas turbine, or a marine gas turbine.

[0025] As shown, the gas turbine 10 as shown is cut off at the centerline 12 of the turbine. As shown, the gas turbine 10 includes a compressor section 14, a combustor section 16 disposed downstream of the compressor section 14, and a turbine section 18 disposed downstream of the combustor section 16. The compressor section 14 can generally be configured to pressurize air flowing into the gas turbine 10. A portion of the pressurized air or working fluid then flows into the combustor section 16, where the air is mixed with and combusted with fuel. The hot combustion gases then flow along an annular hot gas path through a transition piece 20 to the turbine section 18 to drive the gas turbine 10 and generate electricity.

[0026] In several embodiments, compressor section 14 may include an axial compressor 22 having multiple compressor stages characterized by alternating rows of rotor blades 24 and stator blades 26. Specifically, each compressor stage may include a row of circumferentially spaced rotor blades 24 mounted to a compressor rotor wheel 28 and a row of circumferentially spaced stator blades 26 attached to a static compressor housing 30. The alternating rows of rotor blades 24 and stator blades 26 may generally be configured to incrementally increase the pressure of air flowing through the compressor 22, thereby achieving a desired pressure increase. The compressor rotor wheel 28, together with the rotor blades 24, generally comprises the rotating components of the compressor 22, thus forming a compressor rotor assembly 32. For example, in several embodiments, compressor rotor discs 28 may be axially stacked abutting each other around a turbine centerline 12, such that torque can be transmitted between the rotor discs 28.

[0027] The combustion section 16 of the gas turbine 10 typically includes a plurality of burners 34 arranged in a ring array around the turbine centerline 12 (one of which is shown). Each burner 34 is typically configured to receive a portion of pressurized air discharged from the compressor 22, mix the air with fuel to form an air / fuel mixture, and burn the mixture to produce hot combustion gases. As described above, the hot combustion gases can then flow from each burner 34 through a transition member 20 to the turbine section 18 of the gas turbine 10.

[0028] Turbine section 18 typically includes multiple turbine stages, characterized by alternating rows of turbine nozzles 36 and turbine chain buckets 38. Specifically, each turbine stage may include a row of circumferentially spaced turbine nozzles 36 attached to a static turbine housing 40 and a row of circumferentially spaced turbine chain buckets 38 mounted to a turbine rotor wheel 42. The alternating rows of turbine nozzles 36 and chain buckets 38 are typically configured to progressively convert the energy of hot combustion gases into work manifested by the rotation of the turbine rotor wheel 42. The turbine rotor wheel 42, together with the turbine chain buckets 38, typically includes the rotating components of turbine section 18 and thus forms a turbine rotor assembly 44. Similar to compressor rotor wheel 28, turbine rotor wheels 42 are typically stacked together axially along the turbine centerline 12. For example, as Figure 1 As shown, the turbine rotor wheel 42 can be spaced apart from each other by spacer wheels 46, wherein the rotor wheel 42 and spacer wheels 46 are axially stacked against each other, so that torque can be transmitted between the rotor discs 42. Alternatively, spacer wheels can separate the compressor rotor wheel 28.

[0029] like Figure 1 As shown, the gas turbine 10 can define an axial direction A and a circumferential direction C extending around the axial direction A. The gas turbine 10 can also define a radial direction R perpendicular to the axial direction A.

[0030] likeFigure 1 As further shown in the text, and also see Figure 2 The gas turbine 10 may further include a compressor shaft 50 at least partially disposed within the compressor section 14 and a turbine shaft 52 at least partially disposed within the turbine section 18. Shafts 50 and 52 may connect the compressor rotor assembly 32 and the turbine rotor assembly 44 together. As shown, the compressor shaft 50 may include a rear end 51 coupled to the front end 53 of the turbine shaft 52. Each shaft 50 and 52 may include one or more slots, such as a first slot 62 and a second slot 64. The first slot 62 may be annularly defined within the rear end 51 of the compressor shaft 51. Similarly, the second slot 64 may be annularly defined within the front end 53 of the turbine shaft 52. In many embodiments, the compressor shaft 50 may extend axially outward from the compressor section 14 and terminate at the first slot 62 defined within the rear end 51 of the compressor shaft 50. Likewise, the turbine shaft 52 may extend axially inward from the turbine section 18 and terminate at the second slot 64 defined within the front end 53 of the turbine shaft 52. The slots 62 and 64 can form a tight-fitting joint 58, which is used to connect the compressor rotor assembly 32 to the turbine rotor assembly 44 and maintain the coaxial alignment between the compressor shaft 50 and the turbine shaft 52.

[0031] Figure 2 This shows the process of performing maintenance and repairs on it and installing the patch ring 100 therein (as shown in the image). Figures 3 to 9 A cross-sectional view of the shaft assembly 60 (shown). In various embodiments, Figure 2 The shaft assembly 60 shown may be present before or after the operation of the gas turbine 10. As shown, the shaft assembly 60 may include a compressor shaft 50 coupled to the turbine shaft 52 to form a tight-fitting joint 58 therebetween. As shown, the compressor shaft 50 may include a first pre-machined notch 54. Similarly, the turbine shaft 52 may include a second pre-machined notch 56 opposite to the first pre-machined notch 54. The first pre-machined notch 54 may include a first axial extension surface 55, and the second pre-machined notch 56 may include a second axial extension surface 57. As shown, before the patch ring 100 is installed, the first axial extension surface 55 of the first pre-machined notch 54 is in direct contact with the second axial extension surface 57 of the second pre-machined notch 56.

[0032] During turbine disassembly for maintenance or repair, the turbine shaft 50 is disconnected from the compressor shaft 52 and inspected. Both the turbine shaft 50 and compressor shaft 52 can be damaged during this process, and this damage can result from operational wear and tear or from the actual disassembly process itself. First notch 62 and second notch 64 ( Figure 1 () is a common location where this injury occurs.

[0033] Figure 3 andFigure 4 An enlarged cross-sectional view of a shaft assembly 60 is shown in accordance with an embodiment of the present disclosure, with a patch ring 100 in place, for example, after servicing the gas turbine 10. As shown, the shaft assembly 60 can each include a compressor shaft 50, a turbine shaft 52 coupled to the compressor shaft 50, and a tight joint 58 defined therebetween. The compressor shaft 50 can include a first notch 62 annularly defined within the compressor shaft 50. Likewise, the turbine shaft 52 can include a second notch 64 annularly defined within the turbine shaft 52. For example, the first notch 62 and the second notch 64 can be machined in the shafts 50, 52 in a circumferential direction C. The patch ring 100 can be disposed between the first notch 62 of the compressor shaft 50 and the second notch 64 of the turbine shaft 52.

[0034] In many embodiments, the first notch 62 can be positioned opposite the second notch 64. For example, in the embodiment shown in Figure 3 and Figure 4 the first notch 62 of the compressor shaft 50 can be disposed radially inward of the second notch 64 of the turbine shaft 52. However, in other embodiments (not shown), the first notch 62 of the compressor shaft 50 can be disposed radially outward of the second notch 64 of the turbine shaft 52.

[0035] As shown in Figure 3 and Figure 4 the first notch 62 can include a first axially-extending face 66 and a first radially-extending face 68. Likewise, the second notch 64 can include a second axially-extending face 70 and a second radially-extending face 72. As shown in Figure 3 and Figure 4 the axially-extending faces 66, 70 and the radially-extending faces 68, 72 can be substantially planar surfaces. Further, as shown, the axially-extending faces 66, 70 and the radially-extending faces 68, 72 can be the outermost surfaces of the notches 62, 64.

[0036] As used herein, “axially-extending” refers to components and / or surfaces that extend in a relative direction that is substantially parallel and / or coaxially aligned with an axial direction A of the gas turbine 10. Similarly, “radially-extending” refers to components and / or surfaces that extend in a relative direction that is substantially perpendicular to the axial direction A of the gas turbine 10.

[0037] As shown, the first axially-extending face 66 can be radially spaced apart from the second axially-extending face 72, and the patch ring 100 can be positioned therebetween. In some embodiments, the patch ring 100 can be installed between the first notch 62 and the second notch 64 to advantageously provide a design-required interference between the first axially-extending face 66 and the second axially-extending face 72. Additionally, the patch ring 100 can also reduce or prevent axial movement between the axially-extending faces 66, 72 during operation of the gas turbine 10.

[0038] In many embodiments, as shown in FIGS. 1-2, the first slot 62 and the second slot 64 can be axially aligned with one another. For example, the first axial extension face 66 of the first slot 62 can extend axially along the first axial extension face 66 of the second slot 64. In such embodiments, the first radial extension face 68 of the first slot 62 can face the second radial extension face 72 of the second slot 64, overlap the second radial extension face 72, and / or be parallel to the second radial extension face 72. Figure 3 Figure 4 As shown in FIGS. 1-2, the first slot 62 and the second slot 64 can be axially aligned with one another. For example, the first axial extension face 66 of the first slot 62 can extend axially along the first axial extension face 66 of the second slot 64. In such embodiments, the first radial extension face 68 of the first slot 62 can face the second radial extension face 72 of the second slot 64, overlap the second radial extension face 72, and / or be parallel to the second radial extension face 72.

[0039] The patch ring 100 can include a body 102, a first arm 104, and a second arm 106. In the embodiment shown in FIGS. 1-2, the first arm 104 and the second arm 106 can extend radially from the body 102. For example, the first arm 104 can extend radially outward from the body 102, and the second arm 106 can extend radially inward from the body 102. Figure 3 Figure 4 As shown in FIGS. 1-2, the first slot 62 and the second slot 64 can be axially aligned with one another. For example, the first axial extension face 66 of the first slot 62 can extend axially along the first axial extension face 66 of the second slot 64. In such embodiments, the first radial extension face 68 of the first slot 62 can face the second radial extension face 72 of the second slot 64, overlap the second radial extension face 72, and / or be parallel to the second radial extension face 72. Figure 3 Figure 4 As shown in FIGS. 1-2, the first slot 62 and the second slot 64 can be axially aligned with one another. For example, the first axial extension face 66 of the first slot 62 can extend axially along the first axial extension face 66 of the second slot 64. In such embodiments, the first radial extension face 68 of the first slot 62 can face the second radial extension face 72 of the second slot 64, overlap the second radial extension face 72, and / or be parallel to the second radial extension face 72.

[0040] In the embodiment shown in FIGS. 1-2, the first arm 104 and the second arm 106 can extend radially from the body 102. For example, the first arm 104 can extend radially outward from the body 102, and the second arm 106 can extend radially inward from the body 102. Figure 3 Figure 3 As shown in FIGS. 1-2, the first slot 62 and the second slot 64 can be axially aligned with one another. For example, the first axial extension face 66 of the first slot 62 can extend axially along the first axial extension face 66 of the second slot 64. In such embodiments, the first radial extension face 68 of the first slot 62 can face the second radial extension face 72 of the second slot 64, overlap the second radial extension face 72, and / or be parallel to the second radial extension face 72.

[0041] As shown in FIGS. 1-2, the first slot 62 and the second slot 64 can be axially aligned with one another. For example, the first axial extension face 66 of the first slot 62 can extend axially along the first axial extension face 66 of the second slot 64. In such embodiments, the first radial extension face 68 of the first slot 62 can face the second radial extension face 72 of the second slot 64, overlap the second radial extension face 72, and / or be parallel to the second radial extension face 72. Figure 3 As shown in FIGS. 1-2, the first slot 62 and the second slot 64 can be axially aligned with one another. For example, the first axial extension face 66 of the first slot 62 can extend axially along the first axial extension face 66 of the second slot 64. In such embodiments, the first radial extension face 68 of the first slot 62 can face the second radial extension face 72 of the second slot 64, overlap the second radial extension face 72, and / or be parallel to the second radial extension face 72.

[0042] ​​​​The first arm 104 and the second arm 106 can each include a support surface 108, 110, as shown. For example, the support surface 108 of the first arm 104 can be a substantially planar surface that is in direct contact with the second radially extending face 72. Similarly, the support surface 110 of the second arm 106 can be a substantially planar surface that is in direct contact with the first radially extending face 68. For example, the support surface 108 of the first arm and the support surface 110 of the second arm 106 can be substantially planar surfaces that directly abut the second radially extending face 72 and the first radially extending face 68, respectively. The support surfaces 108, 110 of the arms 104, 106 can be used to inhibit movement and / or sliding of the patch ring 100 within the close-coupled joint 58.

[0043] As shown, the first arm 104 and the second arm 106 can each also include an outer surface 112, 114. The outer surface 112 of the first arm can be located axially inward of the support surface 108. Similarly, the outer surface 114 of the second arm can be located axially outward of the support surface 110. As shown, the outer surfaces 112, 114 can be longer in the radial direction than the support surfaces 108, 110. Figure 3

[0044] As shown, the first notch 62 of the compressor shaft 50 and the second notch 64 of the turbine shaft 52 can each also include an outer surface 116, 118. For example, the outer surfaces 116, 118 can be substantially arcuate outer surfaces that are axially spaced apart from the radially extending faces 68, 72 to define a gap 120, 122 therebetween. As shown, the outer surface 116 of the first notch 62 can be located axially inward of the second radially extending face 72 and can define a gap 120 therebetween. Similarly, the outer surface 118 of the second notch 64 can be located axially outward of the second radially extending face 72 and can define a gap 122 therebetween. In many embodiments, the first notch 62 can extend at least partially into the second gap 122 and the second notch 64 can extend at least partially into the first gap 120. Figure 3 Figure 4 In the embodiment shown, the first arm 104 of the patch ring 100 can extend at least partially into the gap 120 and the second arm 106 can extend at least partially into the gap 122. The gaps 120, 122 can be used to create an axial space between the first arm 104 and the second arm 106 in order to allow for thermal expansion during operation of the gas turbine 10. The outer surfaces 112, 114 can advantageously act as intermediate surfaces that prevent the outer surfaces 116, 118 from contacting the radially extending faces 68, 72 due to thermal expansion during operation of the gas turbine 10.

[0045] In the embodiment shown, the first arm 104 of the patch ring 100 can extend at least partially into the gap 120 and the second arm 106 can extend at least partially into the gap 122. The gaps 120, 122 can be used to create an axial space between the first arm 104 and the second arm 106 in order to allow for thermal expansion during operation of the gas turbine 10. The outer surfaces 112, 114 can advantageously act as intermediate surfaces that prevent the outer surfaces 116, 118 from contacting the radially extending faces 68, 72 due to thermal expansion during operation of the gas turbine 10. Figure 3

[0046] Figure 4 ​​​Another embodiment of the patch ring 100 is shown. As shown, the first arm 104 can be coaxially aligned with the second arm 106, i.e., positioned on the same side of the body 102 and share the same axial centerline. In some embodiments, the first arm 104 and the second arm 106 can extend in opposite radial directions from one another to form a generally "T" shape.

[0047] In Figure 4 In the illustrated embodiment, the second notch 64 can also include a radial cutout 212 sized to receive the first arm 104 of the patch ring 100 therein. The radial cutout 212 can be used to limit axial movement of the patch ring 100 within the tight joint 58. For example, during operation of the gas turbine 10, the first arm 104 can be positioned and in contact with the support surface 108 and the outer surface 118 between the support surface 108 and the outer surface 118, thereby limiting axial movement of the patch ring 100 within the tight joint 58. As shown, the radial cutout 212 can also include a cutout support surface 214. The first arm 104 and the second arm 106 can each include a support surface 108, 110, as shown. In many embodiments, the support surface 108 of the first arm 104 can be a substantially flat surface that directly abuts the cutout support surface 214. Similarly, the support surface 110 of the second arm 106 can be a substantially flat surface that directly abuts the first radially extending face 68. The support surfaces 108, 110 of the arms 104, 106 can be used to prohibit movement and / or sliding of the patch ring 100 within the tight joint 58.

[0048] Figure 5 And Figure 6 Various views of the patch ring 100 according to embodiments of the present disclosure are shown. As shown, the first arm 104 and the second arm 106 can each be one continuous annular member that extends in a circumferential direction. The first arm 104 and the second arm 106 can define a circumferential direction C along which they extend.

[0049] Alternatively, as Figure 7 And Figure 8 shown, the first arm 104 can be a plurality of first arms 104' that are spaced apart from one another along the circumferential direction C of the body 102. Likewise, as shown, the second arm 106 can be a plurality of second arms 106' that are spaced apart from one another along the circumferential direction C of the body 102.

[0050] As Figure 7 And Figure 8As shown, the patch ring 100 can also include one or more recesses 124 circumferentially disposed between the plurality of first arms 104' and / or the plurality of second arms 106'. The recesses 124 can extend radially into the body 102 of the patch ring 100 and serve as a passageway for cooling air from the compressor to flow therethrough. For example, air from the compressor section 14 can purge trapped air from the first slot 62 of the compressor shaft 50, the second slot 64 of the turbine shaft 52, and various cavities and crevices of the patch ring 100.

[0051] Figure 9 A flowchart is provided that graphically illustrates a method 300 of servicing a turbomachine, such as the gas turbine 10 described herein, in accordance with one or more additional example embodiments of the present disclosure. As shown, Figure 9 As shown, the method 300 can include the step 302 of machining the first slot 62 within the aft end 51 of the compressor shaft, such a step can occur, for example, after initial operation of the gas turbine 10. The first slot 62 can include a first axially extending face 66 and a first radially extending face 68. Further, the first slot can be annularly defined within the aft end 51 of the compressor shaft 50. The method 300 can also include the step 304 of machining the second slot 64 within the forward end 53 of the turbine shaft 52. The second slot 64 can include a second axially extending face 70 and a second radially extending face 72. Further, the second slot 64 can be annularly defined within the forward end 53 of the turbine shaft 52 and positioned opposite the first slot 62. The method 300 can also include the step 306 of radially installing the patch ring between the first slot 62 and the second slot 64.

[0052] During operation of the gas turbine 10, the body 102 of the patch ring 100 can be used to provide the design-intended interference between the first axially extending face 66 and the second axially extending face 70, even after the surfaces have been serviced and / or machined. For example, Figure 2 As shown, the pre-machined slots 54, 56 can be subject to wear during operation of the gas turbine 10, which requires the various surfaces (e.g., axially extending faces 55, 57) of the pre-machined slots 54, 56 to be serviced to restore the required interference. After the gas turbine 10 has been serviced, the patch ring 100 provides the required interference between the slots 62, 64 (or machined slots).

[0053] This written description uses examples to disclose the application, including the best mode, and also to enable any person skilled in the art to practice the application, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the application is defined by the claims, and can 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 languages of the claims.

Claims

1. A turbomachine, comprising: a compressor section; a combustor section; a turbine section; a compressor shaft at least partially disposed in the compressor section, the compressor shaft having a first pocket annularly defined therein, the first pocket including a first axially extending face and a first radially extending face; a turbine shaft at least partially disposed in the turbine section and coupled to the compressor shaft, the turbine shaft having a second pocket annularly defined therein and positioned opposite the first pocket, the second pocket including a second axially extending face and a second radially extending face; and a patch ring mounted between the first pocket and the second pocket, wherein the patch ring includes a main body, a first arm extending radially outward from the main body, and a second arm extending radially inward from the main body.

2. The turbomachine of claim 1, wherein the first arm and the second arm of the patch ring are axially spaced apart from one another.

3. The turbomachine of claim 1, wherein the first arm and the second arm of the patch ring are coaxially aligned with one another.

4. The turbomachine of claim 1, wherein the main body of the patch ring contacts the first axially extending face of the compressor shaft and the second axially extending face of the turbine shaft.

5. The turbomachine of claim 1, wherein the main body of the patch ring is positioned radially between the first axially extending face and the second axially extending face.

6. The turbomachine of claim 2, wherein the first pocket of the compressor shaft and the second pocket of the turbine shaft each include an outer face, the outer face of the first pocket being disposed axially inward of the second radially extending face of the second pocket, and the outer face of the second pocket being disposed axially outward of the first radially extending face of the first pocket.

7. The turbomachine of claim 2, wherein the first arm of the patch ring contacts the second radially extending face of the second pocket, and the second arm of the patch ring contacts the first radially extending face of the first pocket.

8. The turbomachine of claim 6, wherein a first gap is axially defined between the first arm of the patch ring and the outer face of the first pocket, and a second gap is axially defined between the second arm of the patch ring and the outer face of the second pocket.

9. A method of servicing a turbomachine, the method comprising: machining a first pocket within a rear end of a compressor shaft, wherein the first pocket includes a first axially extending face and a first radially extending face, and wherein the first pocket is annularly defined within the rear end of the compressor shaft; machining a second pocket within a forward end of a turbine shaft, wherein the second pocket includes a second axially extending face and a second radially extending face, and wherein the second pocket is annularly defined within the forward end of the turbine shaft and positioned opposite the first pocket; and ​ ​ mounting a patch ring between the first notch and the second notch, wherein the patch ring includes a body, a first arm extending radially outward from the body, and a second arm extending radially inward from the body.

10. The method of claim 9, wherein the first arm is axially spaced apart from the second arm.

11. The method of claim 10, wherein the body of the patch ring is positioned between and contacts the first axially extending face of the compressor shaft and the second axially extending face of the turbine shaft.

12. The method of claim 10, wherein the first arm of the patch ring contacts the second radially extending face of the second notch and the second arm of the patch ring contacts the first radially extending face of the first notch.

Images