Compressor rotor structure

Abstract

A compressor rotor structure for a turbomachine, such as a compressor, is provided. The disclosed embodiments can benefit from a sealing sleeve that can be arranged to inhibit process fluid handled by the compressor from passing through a corresponding face tooth coupling. The sealing sleeve can be attached to an adjacent structure (e.g., an adjacent impeller body) by a slip fit connection relative to one of the adjacent structures and an interference fit connection relative to the other adjacent structure, which facilitates user-friendly assembly of the sealing sleeve with the adjacent structure.

Description

Background Art

[0001] The disclosed embodiments generally relate to the field of turbomachinery and, more particularly, to rotor structures for turbines, such as compressors.

[0002] Turbomachinery is widely used in the oil and gas industry, such as for performing compression of process fluids, converting thermal energy into mechanical energy, fluid liquefaction, etc. An example of such turbomachinery is a compressor, such as a centrifugal compressor. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] Figure 1 A partial cross-sectional view illustrating a non-limiting embodiment of the disclosed rotor structure as may be used in industrial applications involving turbomachinery, such as but not limited to centrifugal compressors.

[0004] Figure 2 An enlarged cross-sectional view of a portion of an adjacent impeller body.

[0005] Figure 3 An enlarged cross-sectional view of a portion of a rotor shaft and an abutting impeller body. DETAILED DESCRIPTION

[0006] As will be understood by those skilled in the art, turbomachinery, such as centrifugal compressors, can involve rotors with a tension bolt structure (also known in the art as a through-bolt or tie-rod structure), where the tension bolts support multiple impeller bodies and where adjacent impeller bodies can be interconnected with each other by means of elastic averaging coupling techniques, such as including a hirth coupling or a curvic coupling. These coupling types use different forms of face gear teeth (straight teeth and curved teeth, respectively) to form a secure coupling between two components.

[0007] These couplings and associated structures can be subjected to highly variable forces (e.g., centrifugal forces), such as changing from an initial rotor speed of zero revolutions per minute (RPM) to a maximum rotor speed (e.g., as may involve tens of thousands of RPM). Additionally, these couplings and associated structures can be exposed to contaminants and / or by-products that may be present in the process fluid being processed by the compressor. If so exposed, such couplings and associated structures can potentially be affected in a manner that may impact their long-term durability. By way of example, a combination of carbon dioxide (CO 2 )、liquid water, and high pressure levels can result in carbonic acid (H 2 CO 3) The formation of carbonic acid, which is a compound that can corrode, rust, or cause pitting in certain steel components. Physical debris may also be present in the process fluid, and if allowed to reach the face gear connection and associated structures, it may potentially affect their functionality and durability.

[0008] In view of the foregoing considerations, the inventors have recognized that achieving consistent high performance and long-term durability in a centrifugal compressor, for example, may involve using an appropriate sealing structure in the disclosed embodiments to suitably cover the corresponding face gear connection to inhibit the process fluid handled by the compressor from passing through the corresponding face gear connection, and thus improve the above problems.

[0009] In the following detailed description, various specific details are set forth to provide a thorough understanding of such embodiments. However, those skilled in the art will understand that the disclosed embodiments may be practiced without these specific details, that aspects of the present invention are not limited to the disclosed embodiments, and that aspects of the present invention may be practiced in various alternative embodiments. In other instances, methods, procedures, and components that will be well understood by those skilled in the art are not described in detail to avoid unnecessary and cumbersome explanations.

[0010] In addition, various operations may be described as multiple discrete steps performed in a manner that is helpful for understanding the embodiments of the present invention. However, unless otherwise indicated, the described order should not be construed as implying that these operations need to be performed in the order in which they are presented, nor that these operations are even order-dependent. Moreover, repeated use of the phrase "in one embodiment" does not necessarily refer to the same embodiment, although it may. It should be noted that the disclosed embodiments need not be construed as mutually exclusive embodiments, as aspects of these disclosed embodiments may be appropriately combined by those skilled in the art according to the needs of a given application.

[0011] Figure 1 A partial cross-sectional view of a non-limiting embodiment of the disclosed rotor structure 100 as may be used in industrial applications involving turbomachinery, such as but not limited to compressors (e.g., centrifugal compressors, etc.).

[0012] In one disclosed embodiment, the tension bolt 102 extends along the rotor axis 103 between a first end and a second end of the tension bolt 102. The first rotor shaft 104 1 may be fixed to the first end of the tension bolt 102. The second rotor shaft 104 2 may be fixed to the second end of the tension bolt 102. The rotor shafts 104 1 、104 2In the art, it may be referred to as the short axis. It will be understood that in some embodiments, there may be more than two rotor shafts involved.

[0013] A plurality of impeller bodies 106, such as impeller body 106 1 to 106 n may be disposed between the rotor shafts 104 1 、104 2 In the illustrated embodiment, the number of impeller bodies is six and thus n = 6; it will be understood that this is merely an example and should not be construed in a limiting sense with respect to the number of impeller bodies that may be used in the disclosed embodiments. Figure 1 The illustrated embodiment involves a central suspension configuration of back-to-back impeller stages; it will be understood that this is merely an example configuration and should not be construed in a limiting sense with respect to the applicability of the disclosed embodiments.

[0014] The plurality of impeller bodies 106 are supported by tension bolts 102 and are mechanically coupled to each other along the rotor axis by a plurality of face gear coupling portions, such as face gear coupling portion 108 1 to 108 n-1 In the illustrated embodiment, since, as described above, the number of impeller bodies is six, the number of face gear coupling portions between adjacent impeller bodies 106 will be five. It will be understood that two additional face gear coupling portions 109 1 and 109 2 can be used to mechanically couple the impeller bodies 106 n 、106 1 to the respective abutting rotor shafts 104 1 、104 2 respectively. It will be understood that the foregoing arrangement of impeller bodies and face gear coupling portions is merely an example and should not be construed in a limiting sense.

[0015] As can be better understood in Figure 2 , the disclosed embodiments may include corresponding seal sleeves 120, and the corresponding seal sleeves 120 are attached to the respective radially outer surfaces 121, 123 of any two adjacent impeller bodies (e.g., adjacent impeller bodies 106 1 、106 2 ) of the plurality of impeller bodies 106. In this example, the adjacent impeller bodies 106 1 、106 2 are mechanically coupled to each other by the face gear coupling portion 108 1 . It will be understood that the seal sleeve 120 may be configured to have a cylindrical cross-section about the rotor axis.

[0016] The corresponding seal sleeve 120 can extend axially between a first axial edge 122 and a second axial edge 124 of the seal sleeve 120. The seal sleeve 120 can be arranged (e.g., along 360 degrees) to span a circumferentially extending joint 126 located between adjacent impeller bodies 106 1 、106 2 to inhibit process fluid handled by the compressor from passing through the corresponding face gear coupling 108 1 . As described above, the corresponding seal arrangement will be characterized by each pair of adjacent impeller bodies among the remaining adjacent impeller bodies, such as between adjacent impeller bodies 106 2 、106 3 and so on.

[0017] In one non-limiting embodiment, the seal sleeve 120 can be attached to a corresponding one of two adjacent impeller bodies (e.g., impeller body 106 1 ) by an interference fit. That is, a circumferential interference fit around the radially outer surface 121 of the impeller body 106 1 . In one non-limiting embodiment, the radially inner surface 132 of the seal sleeve 120 can include a cushioning portion 135 (e.g., a groove or notch), and the cushioning portion 135 is positioned between the first axial edge 122 and the second axial edge 124 of the seal sleeve 120 to facilitate the assembly of the seal sleeve 120.

[0018] In this example, the seal sleeve 120 can be attached to the other one of two adjacent impeller bodies (e.g., impeller body 106 2 ) by a sliding fit. For example, the radially inner surface 132 of the seal sleeve 120 will have a diameter slightly larger than the diameter of the radially outer surface 123 of the impeller body 106 2 . This type of attachment design involving a sliding fit connection with respect to one of two adjacent impeller bodies and an interference fit connection with respect to the other of two adjacent impeller bodies facilitates user-friendly assembly of the seal sleeve between the corresponding radially outer surfaces 121, 123 of the support structure, e.g., adjacent impeller bodies 106 1 、106 2 .

[0019] In one non-limiting embodiment, a circumferentially extending groove 128 can be provided in adjacent impeller bodies 106 1 、106 2in the first radially outward surface (e.g., the radially outward surface 123) of the radially outward surfaces 121, 123. The sealing member 130 is positioned in the groove 128 to form a seal (e.g., a seal extending along 360 degrees) between the first radially outward surface in the radially outward surfaces (e.g., the radially outward surface 123) and the sealing sleeve 120. The sealing member 130 can be arranged to abut against the corresponding radially inward surface 132 of the sealing sleeve 120 in a compressed manner and against the corresponding surfaces disposed at the corresponding axial positions, such as the surface 125 that partially defines the radial extension of the groove 128. This is effective for strengthening the sealing function of the sealing sleeve 120 attached to the impeller body 106 by means of a sliding fit 2 of the sealing sleeve 120.

[0020] Non-limitingly, the sealing member 130 can be an O-ring, a C-shaped seal, an omega-shaped seal, a fabric seal, or other sealing members. As will be understood by those skilled in the art, the fabric seal can include high-temperature resistant materials such as metals, ceramics, or polymer fibers that can be woven, knitted, or otherwise pressed into a fabric layer.

[0021] As can be better understood in Figure 3 the disclosed embodiments can include another sealing sleeve 140, and the other sealing sleeve 140 is attached to the corresponding abutting impeller body (e.g., the impeller body 106 1 ) of the corresponding radially outward surface 143 and the two rotor shafts 104 1 、104 2 of the corresponding rotor shafts (e.g., the rotor shaft 104 2 ) of the corresponding radially outward surface 141. As described above, the corresponding impeller body 106 1 is mechanically coupled to the corresponding rotor shaft 104 through the end face tooth coupling portion 109 2 . 2

[0022] The other sealing sleeve 140 extends axially between the first axial edge 142 and the second axial edge 144 of the other sealing sleeve. The other sealing sleeve 140 can be arranged (e.g., along 360 degrees) to span the circumferentially extending joint portion 146 located between the impeller body 106 1 and the abutting rotor shaft 104 2 to inhibit the process fluid processed by the compressor from passing through the end face tooth coupling portion 109 2 .

[0023] It will be understood that the other sealing sleeve 140 can be configured to have a cylindrical cross-section around the rotor axis. As described above, the characteristics of the sealing arrangement will lie in the impeller body 106 nand the abutting rotor shaft 104 1 is connected.

[0024] In one non - limiting embodiment, another seal sleeve 140 may be attached to the rotor shaft 104 by an interference fit 2 or to a corresponding one of the abutting impeller bodies (e.g., impeller body 106 1 ). That is, a circumferential interference fit around the radial outer surface 141 of the rotor shaft 104 2 . In this example, another seal sleeve 140 may be attached to the abutting impeller body 106 by a slip fit 1 . For example, the radially inner surface 147 of another seal sleeve 140 will have a diameter slightly larger than the diameter of the radially outer surface 143 of the impeller body 106 1 . This type of attachment design involving a slip fit connection to one of the corresponding abutting impeller bodies (e.g., impeller body 106 1 ) and the corresponding rotor shaft (e.g., rotor shaft 104 2 ) facilitates user - friendly assembly of another seal sleeve between the radially outer surface 143 of the corresponding abutting impeller body (e.g., impeller body 106 1 ) of the support structure, e.g., multiple impeller bodies 106, and the radially outer surface 141 of the corresponding rotor shafts 104 1 , 104 2 . For example, the corresponding rotor shaft (e.g., rotor shaft 104 2 ).

[0025] In one non - limiting embodiment, a circumferentially extending groove 148 may be provided in the first radially outer surface (e.g., radially outer surface 143) of the radially outer surface 141 of the rotor shaft 104 2 and the radially outer surface 143 of the abutting impeller body 106 1 . A seal member 150 is positioned in the groove 148 to form a seal (e.g., along 360 degrees) between the first radially outer surface (e.g., radially outer surface 143) in the radially outer surface and another seal sleeve 140. The seal member 150 may be arranged to abut against the corresponding radially inner surface 147 of another seal sleeve 140 in a compressed manner and against a corresponding surface, such as a radially extending surface 145 that partially defines the groove 148, at a corresponding axial position. This is effective for enhancing the sealing functionality of another seal sleeve 140 attached to the impeller body 106 1 by a slip fit.

[0026] Non-limitingly, the seal member 150 can be an O-ring, a C-shaped seal, an omega-shaped seal, a fabric seal, or other seal member. As will be understood by those skilled in the art, a fabric seal can include high-temperature resistant materials such as metals, ceramics, or polymer fibers that can be woven, knitted, or otherwise pressed into a fabric layer.

[0027] In operation, the disclosed embodiments can use a seal structure that is suitably arranged to cover the face gear coupling and effectively inhibit the process fluid handled by the compressor from passing through the corresponding face gear coupling, and thus inhibit the potential exposure of the face gear coupling and associated structures to contaminants, chemical by-products, and / or physical debris.

[0028] Although the embodiments of the present disclosure have been disclosed in an exemplary form, it will be apparent to those skilled in the art that many modifications, additions, and deletions can be made to the embodiments of the present disclosure without departing from the scope of the invention and its equivalents as set forth in the appended claims.

Claims

1. A rotor structure for a compressor, the rotor structure comprising: a tension bolt and two rotor shafts extending along the rotor axis, the two rotor shafts being respectively attached to the tension bolt; a plurality of impeller bodies disposed between the two rotor shafts, the plurality of impeller bodies being supported by the tension bolt; a plurality of end face tooth coupling portions arranged to mechanically couple the plurality of impeller bodies to each other along the rotor axis; corresponding sealing sleeves attached to the respective radially outer surfaces of any two adjacent impeller bodies among the plurality of impeller bodies, the corresponding sealing sleeves being arranged to span a circumferentially extending joint located between the two adjacent impeller bodies to inhibit process fluid processed by the compressor from passing through the corresponding end face tooth coupling portions, wherein the sealing sleeve is attached to a corresponding one of the two adjacent impeller bodies by an interference fit, wherein the sealing sleeve is attached to the other of the two adjacent impeller bodies by a sliding fit, and a circumferentially extending groove and a sealing member, the circumferentially extending groove being located in a first radially outer surface of the radially outer surfaces, the sealing member being positioned in the groove to form a seal between the first radially outer surface of the radially outer surfaces and the sealing sleeve.

2. The rotor structure according to claim 1, wherein, the sealing member is an O-ring.

3. The rotor structure according to claim 1, wherein, the corresponding sealing sleeve is configured to have a cylindrical cross-section around the rotor axis.

4. The rotor structure according to claim 1, including another sealing sleeve attached to the respective radially outer surface of a corresponding one of the two rotor shafts and the respective radially outer surface of a corresponding impeller body among the plurality of impeller bodies that is in abutting relation with the corresponding rotor shaft, the abutting impeller body being mechanically coupled to the corresponding rotor shaft by another end face tooth coupling portion among the plurality of end face tooth coupling portions, the another sealing sleeve being arranged to span a circumferentially extending joint located between the abutting impeller body and the corresponding rotor shaft to inhibit process fluid processed by the compressor from passing through the another end face tooth coupling portion.

5. The rotor structure according to claim 4, wherein, the another sealing sleeve is attached to one of the corresponding rotor shaft and the abutting impeller body by an interference fit.

6. The rotor structure according to claim 5, wherein, the another sealing sleeve is attached to the other of the corresponding rotor shaft and the abutting impeller body by a sliding fit.

7. The rotor structure according to claim 4, wherein, the corresponding another sealing sleeve is configured to have a cylindrical cross-section around the rotor axis.

8. The rotor structure according to claim 4 further includes a circumferentially extending groove and a sealing member. The circumferentially extending groove is located in the first radially outer surface among the radially outer surfaces, and the sealing member is positioned in the groove to form a seal between the first radially outer surface among the radially outer surfaces and the other sealing sleeve.

9. The rotor structure according to claim 8, wherein, the sealing member is an O-ring.

10. The rotor structure according to claim 1, wherein, the corresponding sealing sleeve is arranged to span 360 degrees across the circumferentially extending joint portion located between the two adjacent impeller bodies.

11. The rotor structure according to claim 4, wherein, the corresponding other sealing sleeve is arranged to span 360 degrees across the circumferentially extending joint portion located between the impeller body and the corresponding rotor shaft.

12. The rotor structure according to claim 1, wherein, the corresponding radially outer surfaces of the two adjacent impeller bodies are adjacent surfaces.

13. The rotor structure according to claim 4, wherein, the corresponding radially outer surfaces of the corresponding rotor shaft and the abutted impeller body are adjacent surfaces.

14. The rotor structure according to claim 1, wherein, the compressor is a centrifugal compressor.

15. A rotor structure for a compressor, the rotor structure comprising: a tension bolt and two rotor shafts extending along the rotor axis, the two rotor shafts being respectively attached to the tension bolt; a plurality of impeller bodies provided between the two rotor shafts, the plurality of impeller bodies being supported by the tension bolt; a plurality of end face tooth couplings arranged to mechanically couple the plurality of impeller bodies to each other along the rotor axis; corresponding sealing sleeves attached to the corresponding radially outer surfaces of any two adjacent impeller bodies among the plurality of impeller bodies, the corresponding sealing sleeves being arranged to span the circumferentially extending joint portion located between the two adjacent impeller bodies to inhibit process fluid processed by the compressor from passing through the corresponding end face tooth couplings; and another sealing sleeve attached to the corresponding radially outer surface of the corresponding rotor shaft among the two rotor shafts and the corresponding radially outer surface of the corresponding impeller body among the plurality of impeller bodies that is in abutting relation with the corresponding rotor shaft, the abutted impeller body being mechanically coupled to the corresponding rotor shaft through the other end face tooth coupling among the plurality of end face tooth couplings, the another sealing sleeve being arranged to span the circumferentially extending joint portion located between the abutted impeller body and the corresponding rotor shaft to inhibit process fluid processed by the compressor from passing through the other end face tooth coupling.

16. The rotor structure according to claim 15, wherein, the another sealing sleeve is attached to one of the corresponding rotor shaft and the abutted impeller body by an interference fit.

17. The rotor structure according to claim 16, Wherein, the other sealing sleeve is attached to the other one of the corresponding rotor shaft and the abutted impeller body by a sliding fit.

18. The rotor structure according to claim 15, wherein, the corresponding other sealing sleeve is configured to have a cylindrical cross-section around the rotor axis.

19. The rotor structure according to claim 15, further comprising a circumferentially extending groove and a sealing member, the circumferentially extending groove is located in the first radially outer surface of the radially outer surfaces, and the sealing member is positioned in the groove to form a seal between the first radially outer surface of the radially outer surfaces and the other sealing sleeve.

20. The rotor structure according to claim 19, wherein, the sealing member is an O-ring, and the O-ring is arranged to span 360 degrees across the circumferentially extending joint between the impeller body and the corresponding rotor shaft.

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