Inner cylinder of steam turbine and steam turbine

Abstract

The utility model provides an inner cylinder of a steam turbine. The inner cylinder comprises a cylinder body and a partition plate sleeve. A steam extraction cavity is formed in the cylinder body, at least one pair of steam extraction openings is formed in the cylinder body, the two steam extraction openings in the pair of steam extraction openings communicate with different positions of the steam extraction cavity correspondingly, and the steam extraction openings are suitable for extracting part of high-pressure steam, passing through the steam extraction cavity, in the cylinder body. The partition plate sleeve is arranged in the cylinder body in a sleeved mode and suitable for dividing the steam extraction cavity into two sub-cavities in the axial direction of the steam turbine, and the two sub-cavities communicate with different steam extraction openings in the pair of steam extraction openings correspondingly, so that high-pressure steam entering the two sub-cavities and exhausted through the steam extraction openings comes from different through-flow stages. According to the inner cylinder of the steam turbine, the technical problems that in an inner cylinder of a traditional steam turbine, due to the fact that the partition plates are directly installed on the steam cylinder, the axial distance between the through-flow stages is small, a steam extraction cavity in the inner cylinder is difficult to cast, sand removal and flaw detection operation is complex, and thermal stress is caused by the fact that the steam extraction cavity needs to be formed in a welding mode are solved.

Description

Technical Field

[0001] The utility model relates to the technical field of steam turbines, in particular to an inner cylinder of a steam turbine and a steam turbine. Background Art

[0002] With the continuous development and changes in the energy market, the application requirements of steam turbines are becoming more and more diversified. Especially in the power sector, in order to meet the requirements of peak load regulation and energy saving, steam turbines need to have better regulation capabilities and thermal efficiency. Among them, the design of the heat recovery system and the structure of the high-pressure inner cylinder play a vital role in the performance and stability of the steam turbine.

[0003] In traditional reaction steam turbines, the partition is directly mounted on the cylinder, and the axial distance between each flow stage is small. This design brings great difficulties to the casting of the steam extraction chamber inside the inner cylinder. Not only are the sand cleaning and flaw detection operations complicated, but welding is usually required to form the steam extraction chamber. However, welding may cause thermal stress and other potential quality problems, affecting the reliability and life of the steam turbine.

[0004] In addition, in order to meet the needs of medium and low load operation, the heat recovery system needs to adjust the extraction position of the high-pressure heater under different loads. This requires the inner cylinder to be equipped with two extraction chambers in a compact axial space. However, this conventional design further increases the difficulty of inner cylinder casting and makes the sealing problem of the center dividing surface between the extraction chambers more prominent. Utility Model Content

[0005] In order to solve at least one of the problems of the prior art, an embodiment of the utility model provides an inner cylinder of a steam turbine, wherein a partition sleeve is arranged inside the inner cylinder, which is suitable for dividing the steam extraction chamber defined inside the inner cylinder body into two sub-chambers in sequence along the axial direction of the inner cylinder, so that the high-pressure steam entering the two sub-chambers comes from different flow levels. Compared with the steam extraction chamber formed by traditional welding, the inner cylinder of the utility model is provided with a single steam extraction chamber, and the larger steam extraction chamber is easy to cast and detect flaws after casting, and the installable partition sleeve makes the steam extraction chamber easy to clean.

[0006] An embodiment of the utility model provides an inner cylinder of a steam turbine, which includes a cylinder body and a partition sleeve. A steam extraction chamber is defined in the cylinder body, and at least one pair of steam extraction ports is provided on the cylinder body. Two of the steam extraction ports in a pair are respectively connected to different positions of the steam extraction chamber, and are suitable for extracting part of the high-pressure steam in the cylinder body through the steam extraction chamber. The partition sleeve is arranged inside the cylinder body, and is suitable for dividing the steam extraction chamber into two sub-chambers along the axial direction. The two sub-chambers are respectively connected to different steam extraction ports in a pair of steam extraction ports, so that the high-pressure steam entering the two sub-chambers and discharged through the steam extraction ports comes from different flow levels.

[0007] According to some embodiments of the utility model, the partition sleeve is embedded in the inner wall of the cylinder body to limit the axial displacement of the partition sleeve relative to the cylinder body.

[0008] According to some embodiments of the utility model, the portion of the inner wall of the cylinder body located in the steam extraction chamber forms a convex portion protruding inward. The end surface of the baffle sleeve facing the convex portion is provided with a concave portion, and the concave portion is suitable for being fitted with the convex portion so that the baffle sleeve is assembled inside the steam extraction chamber.

[0009] According to some embodiments of the utility model, the partition sleeve comprises a semi-circular partition sleeve upper half and a partition sleeve lower half, and the partition sleeve upper half and the partition sleeve lower half are connected along a horizontal mid-section plane.

[0010] According to some embodiments of the utility model, the upper half of the partition sleeve and the lower half of the partition sleeve are provided with flanges, and the upper half of the partition sleeve and the lower half of the partition sleeve are connected by fasteners to limit the leakage of high-pressure steam from the above-mentioned horizontal center plane of the partition sleeve.

[0011] According to some embodiments of the utility model, the cylinder body comprises a semi-circular cylinder body upper half and a cylinder body lower half. The horizontal mid-plane of the partition sleeve and the horizontal mid-plane of the cylinder body are located in the same horizontal plane.

[0012] According to some embodiments of the utility model, the inner cylinder further comprises a stopper, and a groove is formed at the joint position of the lower half of the partition sleeve and the lower half of the cylinder body, and the first end of the stopper is engaged in the groove to limit the radial displacement of the partition sleeve relative to the cylinder body. The second end of the stopper, which is opposite to the first end, extends to the horizontal center plane formed by the upper half of the partition sleeve and the lower half of the partition sleeve. The joint position of the upper half of the partition sleeve and the upper half of the cylinder body presses against the second end of the stopper to limit the circumferential rotation of the partition sleeve relative to the cylinder body.

[0013] According to some embodiments of the utility model, the inner annular surface of the partition sleeve and the inner annular surface of the cylinder body jointly define a flow channel suitable for accommodating the passage of the high-pressure steam.

[0014] According to some embodiments of the utility model, the inner annular surface of the partition sleeve and the inner annular surface of the cylinder body are provided with a plurality of partition grooves and a plurality of steam seal grooves at intervals along the extension direction of the flow channel. The partition grooves are suitable for installing partitions, and the steam seal grooves are suitable for installing steam seal rings, so that different flow levels are formed in the flow channel.

[0015] An embodiment of the utility model provides a steam turbine, which includes an inner cylinder as described in any of the above embodiments, and a rotating assembly arranged inside the inner cylinder.

[0016] According to the inner cylinder of a steam turbine provided by the utility model, a partition sleeve is provided inside the cylinder body, and the partition sleeve is suitable for dividing the steam extraction chamber inside the inner cylinder into two sub-chambers along the axial direction, so that the high-pressure steam flowing into the two sub-chambers comes from different flow levels. The provision of the partition sleeve enables the inner cylinder to only cast a larger steam extraction chamber during the casting process, which facilitates the casting and flaw detection operations after casting, and solves the problem of difficulty in casting the steam extraction chamber in the prior art due to the small axial distance between the flow levels in the inner cylinder and the need to set up two sections of steam extraction chambers. At the same time, the assembled partition sleeve facilitates the cleaning of the steam extraction chamber. The partition sleeve itself can also solve the problem of sealing the center dividing surface between the steam extraction chambers. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a simplified structural diagram of an inner cylinder according to an exemplary embodiment of the utility model;

[0018] Figure 2 is a cross-sectional view of an inner cylinder according to an exemplary embodiment of the present utility model;

[0019] Figure 3 is a top view of a baffle sleeve according to an exemplary embodiment of the present utility model;

[0020] Figure 4 It is a simplified structural diagram of the assembly relationship among the cylinder body, the partition sleeve and the limiting member of the inner cylinder according to an exemplary embodiment of the utility model.

[0021] In the above drawings, the meanings of the reference numerals are as follows:

[0022] 1. Cylinder body;

[0023] 11. Upper part of the cylinder;

[0024] 12. Lower half of the cylinder;

[0025] 13. Partition groove;

[0026] 131. Partition;

[0027] 14. Steam seal groove;

[0028] 141. Steam seal ring;

[0029] 2. Steam extraction port;

[0030] 21. First steam extraction port;

[0031] 22. Second steam extraction port;

[0032] 23. Steam extraction intubation;

[0033] 3. Steam extraction chamber;

[0034] 31. The first steam extraction chamber;

[0035] 32. Second steam extraction chamber;

[0036] 4. Partition cover;

[0037] 41. The partition covers the upper half;

[0038] 42. Partition cover lower half;

[0039] 43. Flange;

[0040] 44. Fasteners;

[0041] 5. Limiting parts; and

[0042] 51. Grooving. DETAILED DESCRIPTION

[0043] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0044] However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present invention. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present invention. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, the description of the known technology is omitted to avoid unnecessary confusion of the concept of the present invention.

[0045] The terms used herein are only for describing specific embodiments and are not intended to limit the present invention. The term "comprising" used herein indicates the existence of features, steps, operations, but does not exclude the existence or addition of one or more other features.

[0046] In the case of using expressions such as "at least one of A, B, and C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.). In the case of using expressions such as "at least one of A, B, or C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B, or C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0047] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0048] In the related art, the partition of the reaction steam turbine is directly set on the cylinder of the steam turbine, so that the axial distance between each flow stage in the cylinder body is small, which increases the difficulty of casting the steam extraction chamber. At the same time, the sand cleaning and flaw detection of the steam extraction chamber are also difficult. Generally, the steam extraction chamber is formed by welding. In order to meet the requirements of peak regulation and energy saving, the steam turbine needs to adapt to more medium and low load operations, resulting in the need for the heat recovery system to adjust the steam extraction position of the high-pressure heater under different loads. The inner cylinder is provided with two sections of steam extraction chambers in a compact axial space. This conventional design further increases the difficulty of casting the inner cylinder. The technical means disclosed in the utility model cancels the partial setting between the two sections of steam extraction chambers, designs it into a special style of partition sleeve, and sets it inside the cylinder body, which effectively solves the technical problem of the difficulty of casting the inner cylinder. The setting of the partition sleeve indirectly overcomes the problem of steam leakage in the center dividing surface seal between the steam extraction chambers. However, the application scenario of the inner cylinder disclosed in the utility model is not limited to reaction steam turbines.

[0049] Figure 1 is a simplified structural diagram of an inner cylinder according to an exemplary embodiment of the utility model; Figure 2 is a cross-sectional view of an inner cylinder according to an exemplary embodiment of the present invention.

[0050] According to an embodiment of the utility model, an inner cylinder of a steam turbine is provided, such as Figure 1 and Figure 2 As shown, it includes a cylinder body 1 and a partition sleeve 4. The interior of the cylinder body 1 defines a steam extraction chamber 3, and the cylinder body 1 is provided with at least one pair of steam extraction ports 2, and the two steam extraction ports 2 in the pair are respectively connected to different positions of the steam extraction chamber 3, and the steam extraction ports 2 are suitable for extracting part of the high-pressure steam in the cylinder body 1 through the steam extraction chamber 3. The partition sleeve 4 is sleeved inside the cylinder body 1, and is suitable for dividing the steam extraction chamber 3 into two sub-chambers along the axial direction, and the two sub-chambers are respectively connected to different steam extraction ports 2 in the pair of steam extraction ports 2, so that the high-pressure steam entering the two sub-chambers and discharged through the steam extraction ports 2 comes from different flow levels.

[0051] According to the above-mentioned setting method, the steam extraction chamber is divided into two sub-chambers by means of a partition sleeve 4 installed inside the cylinder body 1, replacing the two sections of steam extraction chambers formed by welding in the conventional setting. The steam extraction chamber 3 arranged as a whole has a larger space than the single steam extraction chamber in the conventional setting, and is easier to operate such as casting, sand cleaning and flaw detection. Furthermore, the welding method in the conventional setting may bring thermal stress and other potential quality problems, while the setting of the partition sleeve 4 can avoid the occurrence of quality problems during the inner cylinder casting process. The steam extraction chamber 3 is divided into two sub-chambers distributed along the axial direction, so that its steam source comes from different flow levels, which can meet the needs of the heat recovery system for high-pressure steam of different pressures and temperatures.

[0052] In an illustrative embodiment, Figure 1 As shown, the steam extraction port 2 is composed of a straight section and a tapered section, and the straight section is suitable for connecting the steam extraction insert pipe 23 .

[0053] In an illustrative embodiment, Figure 1 As shown, the partition sleeve 4 is constructed to have a T-shaped cross section.

[0054] According to the above arrangement, the T-shaped spacer plate 4 has a simple structure and is easy to cast. At the same time, the T-shaped spacer plate 4 occupies less space, which is convenient for dividing the steam extraction chamber 3 into two larger sub-chambers, which can accommodate more high-pressure steam and improve the efficiency of steam extraction.

[0055] In an illustrative embodiment, Figure 1 As shown, gaps are left between the two ends of the partition sleeve 4 along the axial direction of the cylinder body and the inner wall of the cylinder body 1, and high-pressure steam can reach the inside of the sub-cavity through the gaps.

[0056] According to the above-mentioned setting method, the gap is set between two flow levels, which does not affect the flow of high-pressure steam inside the flow level. At the same time, the gaps at both ends are located at different flow levels to meet the needs of the heat recovery system for high-pressure steam of different pressures and temperatures.

[0057] In an illustrative embodiment, Figure 2 As shown, the partition sleeve 4 divides the steam extraction chamber 3 into a first steam extraction chamber 31 and a second steam extraction chamber 32 which are sequentially distributed along the axial direction of the steam turbine.

[0058] In an illustrative embodiment, Figure 2 As shown, the first extraction chamber 31 is in communication with the through-flow front stage, and the second extraction chamber 32 is in communication with the through-flow rear stage.

[0059] In an illustrative embodiment, the steam source of the first steam extraction chamber 31 comes from before the ninth stage of flow, and the steam source of the second steam extraction chamber 32 comes from after the eleventh stage of flow.

[0060] In an illustrative embodiment, Figure 1 As shown, the partition sleeve 4 is embedded with the inner wall of the cylinder body 1 to limit the axial displacement of the partition sleeve 4 relative to the cylinder body 1.

[0061] In an illustrative embodiment, Figure 2 As shown, the portion of the inner wall of the cylinder body 1 located in the steam extraction chamber 3 forms a convex portion protruding inwardly; the end surface of the partition sleeve 4 facing the convex portion is provided with a concave portion, which is suitable for being fitted with the convex portion so that the partition sleeve 4 is assembled inside the steam extraction chamber 3.

[0062] In an alternative exemplary embodiment, Figure 2 As shown, one end of the partition sleeve 4 facing outward in the circumferential direction forms a convex portion protruding outward; a concave portion is provided on the inner wall of the cylinder body 1 located in the steam extraction chamber 3 opposite to the convex portion, and the concave portion is suitable for being fitted with the convex portion so that the partition sleeve 4 is assembled inside the steam extraction chamber 3.

[0063] According to the above-mentioned arrangement, the cylinder body 1 and the partition sleeve 4 are assembled in a manner in which the concave part and the convex part are fitted together, which can limit the axial displacement of the partition sleeve 4 relative to the cylinder body 1.

[0064] In an illustrative embodiment, the convex portion is configured as continuous annular protrusions distributed along the circumferential direction, and the concave portion is configured as a continuous annular groove corresponding to the convex portion.

[0065] According to the above-mentioned arrangement, when high-pressure steam flows through the cylinder body 1, the partition sleeve 4 is acted upon by the thrust of the high-pressure steam, and the side walls of the convex and concave parts of the partition sleeve 4 and the cylinder body 1 are tightly fitted together at the assembly point, thereby playing a sealing role between the two sub-cavities.

[0066] In an illustrative embodiment, Figure 2 As shown, the partition cover 4 comprises a semi-circular partition cover upper half 41 and a partition cover lower half 42. The partition cover upper half 41 and the partition cover lower half 42 are connected along a horizontal mid-plane.

[0067] According to the above arrangement, the partition sleeve 4 is arranged in the form of an upper and lower half partition sleeve 41 and a lower half partition sleeve 42, which can be easily installed and disassembled.

[0068] Figure 3 is a top view of a baffle sleeve according to an exemplary embodiment of the present invention.

[0069] In an illustrative embodiment, Figure 3 As shown, the upper half 41 of the partition sleeve and the lower half 42 of the partition sleeve are provided with flanges 43, and the upper half 41 of the partition sleeve and the lower half 42 of the partition sleeve are connected by fasteners 44 to limit the leakage of high-pressure steam from the horizontal center plane of the partition sleeve 4.

[0070] According to the above arrangement, a connecting flange 43 is provided between the partition sleeve upper half 41 and the partition sleeve lower half 42 in a bisected form to ensure the sealing of the center dividing surface.

[0071] In an illustrative embodiment, Figure 3 As shown, the flange 43 is fixed by fasteners 44, and the fasteners 44 are evenly distributed on the edge of the flange 43 and located between the two sub-cavities, which is conducive to improving the sealing effect.

[0072] In an exemplary embodiment, the fastener 44 includes a fastening bolt, a nut, and a washer.

[0073] In an illustrative embodiment, Figure 2 As shown, the cylinder body 1 comprises a semi-circular cylinder body upper half 11 and a cylinder body lower half 12. The horizontal center plane of the partition plate sleeve 4 and the horizontal center plane of the cylinder body 1 are located in the same horizontal plane.

[0074] In an illustrative embodiment, a pair of steam extraction ports 2 include a first steam extraction port 21 and a second steam extraction port 22. The first steam extraction port 21 is disposed on the upper half 11 of the cylinder body, and the first steam extraction port 21 is connected to the first steam extraction chamber 31; the second steam extraction port 22 is disposed on the lower half 12 of the cylinder body, and the second steam extraction port 22 is connected to the second steam extraction chamber 32.

[0075] Figure 4 It is a simplified structural diagram of the assembly relationship among the cylinder body, the partition sleeve and the limiting member of the inner cylinder according to an exemplary embodiment of the utility model.

[0076] In an illustrative embodiment, Figure 4 As shown, the inner cylinder further includes a stopper 5, and the combination position of the partition sleeve lower half 42 and the cylinder body lower half 12 forms an embedding groove 51 extending in the circumferential direction. The first end of the stopper 5 is embedded in the embedding groove 51, and the second end of the stopper 5, which is away from the first end, extends to the horizontal center plane formed by the partition sleeve upper half 41 and the partition sleeve lower half 42. The combination position of the partition sleeve upper half 41 and the cylinder body upper half 11 presses against the second end of the stopper 5 to limit the circumferential rotation of the partition sleeve 4 relative to the cylinder body 1.

[0077] According to the above-mentioned arrangement, through the arrangement of the limit member 5, the partition sleeve 4 can be stably fixed at the center position of the cylinder body 1, avoiding loosening or circumferential rotation of the partition sleeve 4 during operation, thereby ensuring the normal operation and stability of the inner cylinder.

[0078] In an illustrative embodiment, the limiting member 5 is configured to be L-shaped, and one bent end of the limiting member 5 is engaged with the lower half 42 of the partition sleeve.

[0079] According to the above arrangement, the L-shaped stopper 5 can provide better support on the partition sleeve 4 and enhance its stability. The L-shaped stopper 5 can be installed and removed more conveniently, reducing the difficulty and time cost of operation. The stopper 5 is allowed to better adapt and position in a limited space, especially when the inner cylinder space is relatively compact, and this design can make more efficient use of space.

[0080] In an illustrative embodiment, Figure 1 As shown, the inner annular surface of the partition sleeve 4 and the inner annular surface of the cylinder body 1 jointly define a flow channel suitable for accommodating the passage of the high-pressure steam.

[0081] In an illustrative embodiment, as shown in Figure 1, the inner annular surface of the baffle sleeve 4 and the inner annular surface of the cylinder body 1 are provided with a plurality of baffle grooves 13 and a plurality of steam seal grooves 14 at intervals along the extension direction of the flow channel. The baffle groove 13 is suitable for installing a baffle 131, and the steam seal groove 14 is suitable for installing a steam seal ring 141, so that different flow levels are formed in the flow channel.

[0082] According to the above arrangement, a plurality of baffle grooves 13 and steam seal grooves 14 are arranged on the baffle sleeve 4, which can form different levels of through-flow, thereby optimizing the structure of the flow channel and making the steam sources of the two sub-cavities come from different through-flow levels. The design of the steam seal groove can be installed with a steam seal ring, thereby enhancing the steam tightness of the cylinder, reducing steam leakage, and improving the working efficiency and stability of the cylinder.

[0083] According to another aspect of the embodiment of the utility model, a steam turbine is provided, comprising an inner cylinder as described in any of the above embodiments; and a rotating assembly, wherein the rotating assembly is arranged inside the inner cylinder.

[0084] According to the above arrangement, during the casting process of the inner cylinder of the steam turbine, the larger steam extraction chamber 3 in the cylinder body 1 is easy to cast and inspect after casting, and the detachable partition sleeve 4 in the steam extraction chamber 3 is also convenient for cleaning the steam extraction chamber 3. Furthermore, the middle face seal of the partition sleeve 4 itself ensures the sealing between the two sub-cavities.

[0085] So far, the embodiments of the utility model have been described in detail in conjunction with the accompanying drawings. It should be noted that the implementation methods not shown or described in the drawings or the body of the specification are all forms known to ordinary technicians in the relevant technical field and are not described in detail. In addition, the above definitions of each component are not limited to the various specific structures, shapes or methods mentioned in the embodiments, and ordinary technicians in the field can simply change or replace them.

[0086] It should also be noted that, in the specific embodiments of the present invention, unless otherwise indicated, the numerical parameters in this specification and the attached claims are approximate values ​​and can be changed according to the desired characteristics obtained through the content of the present invention. Specifically, all numbers used in the specification and claims to express the size, range conditions, etc. of the composition should be understood to be modified by the term "about" in all cases. In general, the meaning of the expression refers to the change of ±10% in some embodiments, ±5% in some embodiments, ±1% in some embodiments, and ±0.5% in some embodiments by a specific number.

[0087] Those skilled in the art will appreciate that the features described in the various embodiments and / or claims of the present invention may be combined and / or combined in various ways, even if such combinations and / or combinations are not explicitly described in the present invention. In particular, the features described in the various embodiments and / or claims of the present invention may be combined and / or combined in various ways without departing from the spirit and teachings of the present invention. All of these combinations and / or combinations fall within the scope of the present invention.

[0088] The specific embodiments described above further illustrate the purpose, technical solutions and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An inner cylinder of a steam turbine, characterized in that: include: A cylinder body (1), wherein a steam extraction chamber (3) is defined in the cylinder body (1), and the cylinder body (1) is provided with at least one pair of steam extraction ports (2), wherein two of the steam extraction ports (2) in a pair are respectively connected to different positions of the steam extraction chamber (3) and are suitable for extracting part of the high-pressure steam in the cylinder body (1) through the steam extraction chamber (3); as well as A partition sleeve (4) is sleeved inside the cylinder body (1) and is suitable for dividing the steam extraction chamber (3) into two sub-chambers along the axial direction. The two sub-chambers are respectively connected to different steam extraction ports (2) in a pair of steam extraction ports (2), so that high-pressure steam entering the two sub-chambers and discharged through the steam extraction ports (2) comes from different flow levels.

2. The inner cylinder according to claim 1, characterized in that: The partition sleeve (4) is embedded in the inner wall of the cylinder body (1) to limit the axial displacement of the partition sleeve (4) relative to the cylinder body (1).

3. The inner cylinder according to claim 2, characterized in that: The portion of the inner wall of the cylinder body (1) located in the steam extraction chamber (3) forms a convex portion protruding inwards; The end surface of the partition sleeve (4) facing the convex portion is provided with a concave portion, and the concave portion is suitable for being fitted with the convex portion so that the partition sleeve (4) is assembled inside the steam extraction chamber (3).

4. The inner cylinder according to any one of claims 1 to 3, characterized in that: The partition sleeve (4) comprises a semi-annular partition sleeve upper half (41) and a partition sleeve lower half (42); The upper half (41) of the partition sleeve and the lower half (42) of the partition sleeve are connected along a horizontal mid-plane.

5. The inner cylinder according to claim 4, characterized in that: The upper half (41) of the partition sleeve and the lower half (42) of the partition sleeve are provided with flanges (43), and the upper half (41) of the partition sleeve and the lower half (42) of the partition sleeve are connected by fasteners (44) to limit the leakage of high-pressure steam from the horizontal center plane of the partition sleeve (4).

6. The inner cylinder according to claim 4, characterized in that: The cylinder body (1) comprises a semi-annular cylinder body upper half (11) and a cylinder body lower half (12); Wherein, the horizontal mid-plane of the partition sleeve (4) and the horizontal mid-plane of the cylinder body (1) are located in the same horizontal plane.

7. The inner cylinder according to claim 6, characterized in that: It also includes a limiting member (5), wherein the combination position of the lower half (42) of the partition sleeve and the lower half (12) of the cylinder body forms an embedding groove (51), and the first end of the limiting member (5) is embedded in the embedding groove (51) to limit the radial displacement of the partition sleeve (4) relative to the cylinder body (1); The second end of the limiting member (5) which is away from the first end extends to a horizontal mid-plane formed by the upper half (41) of the partition sleeve and the lower half (42) of the partition sleeve; The combined position of the partition sleeve upper half (41) and the cylinder body upper half (11) presses against the second end of the limiting member (5) to limit the circumferential rotation of the partition sleeve (4) relative to the cylinder body (1).

8. The inner cylinder according to any one of claims 1 to 3, characterized in that: The inner annular surface of the partition sleeve (4) and the inner annular surface of the cylinder body (1) jointly define a flow channel suitable for accommodating the passage of the high-pressure steam.

9. The inner cylinder according to claim 8, characterized in that: The inner annular surface of the partition sleeve (4) and the inner annular surface of the cylinder body (1) are provided with a plurality of partition grooves (13) and a plurality of steam seal grooves (14) at intervals along the extension direction of the flow channel; The partition plate groove (13) is suitable for installing a partition plate (131), and the steam seal groove (14) is suitable for installing a steam seal ring (141), so that different flow levels are formed in the flow channel.

10. A steam turbine, characterized in that: include: An inner cylinder as claimed in any one of claims 1 to 9; as well as The rotating assembly is arranged inside the inner cylinder.

Images