Compressor, and method for operating a compressor
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SIEMENS ENERGY GLOBAL GMBH & CO KG
- Filing Date
- 2025-12-22
- Publication Date
- 2026-08-06
Smart Images
Figure EP2025088697_06082026_PF_FP_ABST
Abstract
Description
2024PF00711 1 Description TÜ H Compressors and methods for operating a compressor
[0001] The invention relates to a rotor for a compressor, wherein the rotor comprises several disks, the disks being held together by a tie rod, with a space formed between the tie rod and the disks, and wherein the rotor is designed to compress a process medium along a flow path.
[0002] The invention further relates to a method for operating a compressor, wherein the compressor has a rotor rotatably mounted along an axis of rotation, wherein a housing is arranged around the rotor, wherein the rotor has several disks along the axis of rotation, wherein the disks are connected to a tie rod formed along the axis of rotation, wherein a space extends along the axis of rotation between the tie rod and the disks.
[0003] A compressor, also called a pressure booster, is a device used to increase the pressure of a process medium. The operation of a compressor can be divided into several steps. Essentially, a compressor comprises a rotatably mounted rotor and a housing arranged around the rotor.
[0004] A rotor for a centrifugal compressor is a central component responsible for accelerating and compressing the process medium. The rotor consists of several components that work together to achieve the desired compression performance. A special design feature used in some rotor designs is the tie rod. The tie rod is a central element that runs through the hub of an impeller and secures the 2024PF00711 2 The tie rod holds the various components of the rotor together. It is typically a long, high-strength bolt or rod that runs axially through the rotor and is secured at both ends. The tie rod ensures the structural integrity of the rotor and prevents the components from coming loose under the high centrifugal forces. BACKGROUND
[0005] Assembled rotors held together by a tie rod are, by definition, hollow. Consequently, corrosion processes can occur inside, for example, due to moisture. To prevent the formation of a microenvironment in this enclosed space, which can include moisture and thus potentially cause corrosion, the interior must be constantly perfused or ventilated with a suitable gas.
[0006] One way to create airflow inside the rotor is to open the rotor at two points along the flow path that exhibit a pressure difference. This generates a constant gas flow through the rotor.
[0007] Axial compressors essentially comprise a rotatably mounted rotor and a casing arranged around the rotor. A flow channel is formed between the rotor and the casing, defined by compressor guide vanes and compressor impeller blades, with the guide vanes located on the casing and the impeller blades on the rotor. The energy level of the process medium increases as it flows through the axial compressor because the impeller blades exert torque on the medium. The guide vanes slow the process medium and convert the circulating component of the flow into pressure. Compressors are typically driven by an electric motor or a steam or gas turbine. SUMMARY OF THE INVENTION
[0008] This is where the invention comes in. 2024PF00711 3
[0009] The object of the invention is to provide a rotor for a compressor in which the occurrence of corrosion is minimized.
[0010] This problem is solved by a rotor for a compressor, wherein the rotor comprises several disks, the disks being held together by a tie rod, a space being formed between the tie rod and the disks, the rotor being designed to compress a process medium along a flow path, the rotor having a first opening that establishes a fluid connection between the space and a first region, the first opening having a first radius, the rotor having a second opening that establishes a fluid connection between the space and a second region, the second opening having a second radius, the second radius being larger than the first radius.
[0011] The problem is also solved by a method for operating a compressor, wherein the compressor has a rotor rotatably mounted along an axis of rotation, wherein a housing is arranged around the rotor, wherein the rotor has several disks along the axis of rotation, wherein the disks are connected to a tie rod formed along the axis of rotation, wherein a space extends along the axis of rotation between the tie rod and the disks, wherein the rotor has a first opening that establishes a fluid connection between the space and a first region, wherein the first opening has a first radius, wherein the rotor has a second opening that establishes a fluid connection between the space and a second region, wherein the second opening has a second radius, the second radius being larger than the first radius. DESCRIPTION OF THE INVENTION
[0012] The rotor is opened at points outside the compression flow path. To promote flow through the rotor, the 2024PF00711 4 Openings are arranged on different radii, so that due to the different circumferential speeds a conveying height is generated which, due to the rotation of the runner, allows the gas to be conveyed through its interior.
[0013] Advantageous embodiments are the subject of the dependent claims.
[0014] The dependent claims list further advantages that can be combined in any way to achieve further advantages.
[0015] In a further advantageous embodiment, the inlet bore is inclined in the direction of rotation of the rotor. This creates additional dynamic pressure at the inlet of the first opening.
[0016] The first and second openings are neither in the compression flow path nor do they exhibit a pressure difference. Nevertheless, by generating a delivery head between the first and second openings, the desired effect of a constant flow through the rotor's space is achieved. BRIEF DESCRIPTION OF THE DRAWINGS [OOP] An embodiment of the invention will now be explained in more detail with reference to the following figures.
[0018] The properties, features and advantages of this invention described above, as well as the manner in which they are achieved, will become clearer and more easily understood in connection with the following description of the exemplary embodiments, which are explained in more detail in conjunction with the drawings.
[0019] Identical components or components with the same function are identified by the same reference numerals. 2024PF00711 5
[0020] Exemplary embodiments of the invention are described below with reference to the drawings. These drawings are not intended to be drawn to scale; rather, where helpful for explanation, they are presented in a schematic and / or slightly distorted form. For further details regarding the teachings directly apparent from the drawings, reference is made to the relevant prior art.
[0021] They show:
[0022] FIG 1 a schematic representation of a compressor
[0023] FIG 2 shows a schematic representation of a rotor according to the invention.
[0024] FIG 3 shows a schematic representation of part of the rotor
[0025] FIG 4 a schematic representation of a cross-section of the rotor DESCRIPTION OF THE VERSIONS
[0026] Figure 1 shows a schematic representation of a compressor 1. The compressor 1 shown in Figure 1 is a centrifugal compressor. The centrifugal compressor, also called a radial compressor, is designed to increase the pressure and velocity of a process medium. The process medium is drawn into the compressor 1 and enters the center of the impeller 2. For clarity, only one impeller 2 is shown with the reference numeral 2. The impeller 2 is part of a rotor 3, which is rotatable about an axis of rotation 4. The rotor 3 consists of several impeller discs 5, which are connected to each other by means of a tie rod 6. For clarity, only one impeller disc 5 is shown with the reference numeral 5.
[0027] The impeller 2 comprises several blades that rotate at high speed. When the process medium enters the impeller 2, it is accelerated radially outwards by centrifugal force. This acceleration 2024PF00711 6 This increases the kinetic energy of the process medium. After the process medium leaves the impeller 2, it enters a diffuser 7. For clarity, only one diffuser 7 is shown, designated with the reference symbol 7. For the sake of clarity, the housing 8 surrounding the rotor 3 is shown only schematically and not completely. The diffuser 7 comprises a series of fixed blades or channels that slow down the flow of the process medium. This slowing of the process medium converts its kinetic energy into pressure energy, resulting in an increase in the pressure of the process medium. The flow of the process medium follows a flow path 9. The now compressed process medium leaves compressor 1 in a radial direction and can be fed into downstream systems or processes. The main advantages of a centrifugal compressor are its ability to achieve high pressure ratios, its compact design, and its reliability. Figure 2 shows a further schematic representation of the rotor 3. The rotor 3 is opened at points that lie outside the compression flow path 9 and have no pressure difference. A gap 13 is formed between the tie rod 6 and an inner surface 12 of the rotor, through which a gas flows during operation. To facilitate the flow of the gas through the rotor 3, the rotor 3 has a first opening 10 located at a radius R1 from the axis of rotation 4. At the other end of the rotor 3, a second opening 11 is arranged at a radius R2 from the axis of rotation 4. The first opening 10 and the second opening 11 are arranged at different radii, so that, due to the different circumferential speeds, a theoretical delivery head is generated, which, due to the rotation of the rotor 3, causes the gas to be conveyed through its interior.In the example shown in Figure 2, the radius R1 of the first opening is smaller than the radius R2 of the second opening, so that the gas flows along the flow direction 14.2024PF00711. 7
[0031] This ensures that the space 13 is constantly supplied with gas, thus preventing the formation of corrosion.
[0032] Figure 3 shows an enlarged view of the rotor 3 in the region of the second opening 11. The second opening 11 is formed at an angle b 18 to the axis of rotation 4, and extends within a thrust-compensating piston 15. The gas flowing out of the second opening 11 is guided from the compressor 1 and further processed. Figure 4 shows a cross-sectional view of the rotor 3. The cross-sectional view shows the arrangement of the first opening 10. It can be seen that the first opening 10 is arranged at an angle α 19 to a radial direction 16. In operation, the rotor 3 rotates counterclockwise. Arrow 17 symbolizes a flow that flows against the first opening 10. This creates a dynamic pressure, which increases the pressure gradient between the first opening 10 and the second opening 11. This improves the flow in the space 13.
[0034] The first opening 10 is located behind a dry gas seal 20 during operation.
[0035] Although the invention has been illustrated and described in detail by the preferred embodiment, the invention is not limited by the disclosed examples and other variants can be derived by a person skilled in the art without leaving the scope of protection of the invention.
Claims
2024PF00711 8 Claims 1. Rotor (3) for a compressor (1 ), wherein the rotor (3) comprises several disks (5), wherein the disks (5) are held together by a tie rod (6), wherein a gap (13) is formed between the tie rod (6) and the disks (5), wherein the rotor (3) is designed to compress a process medium along a flow path (9), wherein the rotor (3) has a first opening (10) which establishes a fluid-flow connection between the space (13) and a first region, wherein the first opening (10) has a first radius R1, wherein the rotor (3) has a second opening (11) which establishes a fluid-flow connection between the space (13) and a second area, wherein the second opening (11) has a second radius R2, where the second radius R2 is larger than the first radius R1.
2. Rotor (3) according to claim 1 , wherein the first radius R1 and the second radius R2 are chosen such that during operation, different pressures are created at the first opening (10) and at the second opening (11) by a rotation of the rotor (3), so that a flow along the space (13) is possible.
3. Rotor (3) according to claim 1 or 2, wherein the first opening (10) and the second opening (11) are arranged such that they allow a uniform flow of a medium through the space (13).
4. Rotor (3) according to any one of the preceding claims, wherein the first area in operation is arranged behind a dry gas seal (20). 2024PF00711 9 5. Rotor (3) according to any one of the preceding claims, wherein the second area is arranged behind a thrust compensation piston (15) during operation.
6. Rotor (3) according to any one of the preceding claims, wherein the rotor (3) is rotatably oriented along an axis of rotation (4), wherein the second opening (11) and the axis of rotation (4) are arranged at an angle b to each other.
7. Rotor (3) according to any one of the preceding claims, wherein the first opening (10) is arranged at an angle α to a radial direction (16) with respect to the axis of rotation (4).
8. Rotor (3) according to any one of the preceding claims, wherein the rotor (3) is designed for use in a centrifugal compressor.
9. Method for operating a compressor (1), wherein the compressor (1) has a rotor (3) rotatably mounted along a rotational axis (4), wherein a housing is arranged around the rotor (3), wherein the rotor (3) has several disks (5) along the axis of rotation (4), wherein the disks (5) are connected to a tie rod (6) formed along the axis of rotation (4), wherein a space (13) extends between the tie rod (6) and the disks (5) along the axis of rotation (4), wherein the rotor (3) has a first opening (10) which establishes a fluid-flow connection between the space (13) and a first region, wherein the first opening (10) has a first radius R1, wherein the rotor (3) has a second opening (11) which provides a fluid-flow connection between the space (13) and a 2024PF00711 10 second area produces wherein the second opening (11) has a second radius R2, wherein the second radius R2 is larger than the first radius R1.
10. Method according to claim 9, the different radii of the first radius R1 and the second radius R2 generate a pressure difference, allowing a gas to flow along the space (13).