Embedded compact exhaust hood structure of steam turbine

Abstract

The invention discloses an embedded compact exhaust hood structure of a steam turbine, belongs to the technical field of cylinder structures, and aims to solve the problem that high-power energy conversion is difficult to complete due to the fact that an axial space of an existing compact single-cylinder steam turbine is limited. A rear X-stage cylinder body structure in a cylinder body extends into a steam exhaust volute structure of the steam exhaust cylinder, the rear X-stage cylinder body structure and the steam exhaust volute structure are supported through a supporting unit, and due to the fact that the tail end of a cylinder body needs to extend into a steam exhaust volute, interference can occur when traditional bolt connection is adopted, and the tail end of the cylinder body extends into the steam exhaust volute. Therefore, the key connection mode is used for replacing traditional bolt connection, and on the basis that accurate positioning and reliable connection are guaranteed, the conditions of flare angle and deformation of the tail end of the cylinder body can be effectively prevented. The exhaust hood structure is used in the steam turbine.

Description

Technical Field

[0001] The invention belongs to the technical field of cylinder structures, and in particular relates to an embedded compact exhaust cylinder structure of a steam turbine. Background Art

[0002] In the process of designing the flow passage of the cylinder, in order to ensure that the steam can effectively expand and work in a cylinder and convert kinetic energy into mechanical energy, the length and number of blades are key indicators. Long blades can make the steam expand and work more fully in a single stage, but too long blades will lead to problems such as poor strength and large radial dimensions. Therefore, in order to improve the efficiency of the steam turbine, the method of increasing the number of blades is often used. However, in a single-cylinder steam turbine, the more stages there are, the greater the demand for axial space of the cylinder. Therefore, it is difficult to complete high-power energy conversion in a compact single-cylinder steam turbine with limited axial space. Summary of the invention

[0003] The present invention aims to solve the problem that a compact single-cylinder steam turbine with limited axial space is difficult to complete high-power energy conversion; and further provides a steam turbine embedded compact exhaust cylinder structure;

[0004] A steam turbine embedded compact exhaust cylinder structure, the exhaust cylinder structure comprises an exhaust volute and a cylinder body, a rear X-stage cylinder structure in the cylinder body extends into the exhaust volute structure of the exhaust cylinder, and the rear X-stage cylinder structure and the exhaust volute structure are supported by a support unit;

[0005] Furthermore, the value range of X in the rear X-stage cylinder structure is 1 to 3;

[0006] Further, the support unit includes 2N support rods, N is a positive integer, and the 2N support rods are equidistantly arranged between the rear X-stage cylinder structure and the exhaust volute structure along the circumferential direction, and one end of each support rod is welded and fixed to the end of the rear X-stage cylinder structure, and the other end of each support rod is welded and fixed to the inner end wall of the exhaust volute structure;

[0007] Furthermore, the cylinder body is a split structure, the cylinder body includes an upper cylinder and a lower cylinder, and the end cylinder body of the upper cylinder and the end cylinder body of the lower cylinder are spliced ​​and fixed by two key units;

[0008] Furthermore, two key units are symmetrically arranged on the joint surface of the upper cylinder and the lower cylinder along the axis of the cylinder body, and the top of each key unit is embedded in the end cylinder body of the upper cylinder, and the bottom of each key unit is embedded in the end cylinder body of the lower cylinder;

[0009] Further, the key unit includes a longitudinal key and an axial key, the longitudinal key has a length extending direction perpendicular to the axis of the cylinder body, and the axial key has a length extending direction identical to the axis extending direction of the cylinder body;

[0010] Further, the 2N support rods are evenly divided into two support rod groups, and the two support rod groups are symmetrically arranged along the joint surface of the upper cylinder and the lower cylinder, the upper support rod group is located between the end cylinder body of the upper cylinder and the exhaust volute structure, and the lower support rod group is located between the end cylinder body of the lower cylinder and the exhaust volute structure;

[0011] Furthermore, the value range of N is 3 to 5;

[0012] Furthermore, the axis of the support rod is arranged parallel to the axis of the cylinder body.

[0013] The beneficial effects of this application compared to the prior art are as follows:

[0014] 1. The application provides a steam turbine embedded compact exhaust cylinder structure. Compared with the traditional cylinder structure, the last few stages of the cylinder are embedded in the exhaust volute while ensuring the exhaust area. This arrangement can minimize the axial distance of the cylinder while ensuring that the steam turbine can perform high-power conversion, so that a compact single-cylinder steam turbine with limited axial space can also complete high-power energy conversion.

[0015] 2. The application provides a steam turbine embedded compact exhaust cylinder structure, which optimizes the connection method of the cylinder body according to the design requirements. Considering that the end of the cylinder body needs to extend into the exhaust volute and there is a lack of working space for installing bolts, the application uses a key connection to replace the traditional bolt connection. While ensuring accurate positioning and reliable connection, it can also effectively prevent the end of the cylinder body from angling and deformation.

[0016] 3. The present application provides a steam turbine embedded compact exhaust cylinder structure, wherein the exhaust cylinder structure involved adopts a single-cylinder design, has a relatively low processing cost, a relatively short processing cycle, and is very economical. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the internal structure of the embedded compact exhaust cylinder structure described in the present application (a view in the direction of the upper half cylinder with the joint surface of the upper and lower cylinder bodies as the dividing plane);

[0018] In the figure, 1 is the exhaust volute, 2 is the rear X-stage cylinder structure, 3 is the support rod, 4 is the longitudinal key and 5 is the axial key. DETAILED DESCRIPTION

[0019] Specific implementation method 1: Combination Figure 1 To describe this embodiment, a steam turbine embedded compact exhaust cylinder structure is provided in this embodiment, the exhaust cylinder structure includes an exhaust volute 1 and a cylinder block, a rear X-stage cylinder body structure 2 in the cylinder block extends into the exhaust volute structure 1 of the exhaust cylinder, and the rear X-stage cylinder body structure 2 and the exhaust volute structure 1 are supported by a support unit.

[0020] The exhaust cylinder structure provided in this embodiment embeds the rear X-stage cylinder structure 2 in the cylinder body into the exhaust volute while ensuring the exhaust area, so that a compact single-cylinder steam turbine with limited axial space can also complete high-power energy conversion, allowing the steam to expand and do work more fully in the single-cylinder steam turbine body.

[0021] Specific implementation method 2: Combination Figure 1 This embodiment is described. The difference between this embodiment and the first embodiment is that the value range of X in the rear X-stage cylinder structure 2 is 1 to 3. The other components and connection methods are the same as those in the first embodiment.

[0022] Specific implementation method three: Combination Figure 1 This embodiment is described. The difference between this embodiment and the second embodiment is that the support unit includes 2N support rods 3, N is a positive integer, and the 2N support rods 3 are equidistantly arranged between the rear X-stage cylinder structure 2 and the exhaust volute structure 1 along the circumferential direction, and one end of each support rod 3 is welded and fixed to the end of the rear X-stage cylinder structure 2, and the other end of each support rod 3 is welded and fixed to the inner end wall of the exhaust volute structure 1. Other components and connection methods are the same as those of the second embodiment.

[0023] In the present embodiment, considering that the rear X-stage cylinder structure 2 is a cantilever support structure in the exhaust volute structure 1, vibration will occur when the steam turbine is working, affecting the working stability of the steam turbine. Therefore, a support rod structure is used as a support structure between the exhaust volute structure 1 and the rear X-stage cylinder structure 2, which is used to improve the cantilever strength of the rear X-stage cylinder structure 2 and ensure its stability during operation.

[0024] Specific implementation method four: Combination Figure 1 This embodiment is described. The difference between this embodiment and the third embodiment is that the cylinder body is a split structure, the cylinder body includes an upper cylinder and a lower cylinder, and the end cylinder body of the upper cylinder and the end cylinder body of the lower cylinder are spliced ​​and fixed by two key units. Other components and connection methods are the same as those of the third embodiment.

[0025] Specific implementation method five: Combination Figure 1 This embodiment is described. The difference between this embodiment and the fourth embodiment is that two key units are symmetrically arranged on the joint surface of the upper cylinder and the lower cylinder along the axis of the cylinder body, and the top of each key unit is embedded in the end cylinder body of the upper cylinder, and the bottom of each key unit is embedded in the end cylinder body of the lower cylinder. The other components and connection methods are the same as those of the fourth embodiment.

[0026] Specific implementation method six: Combination Figure 1This embodiment is described. This embodiment is different from the fifth embodiment in that the key unit includes a longitudinal key 4 and an axial key 5. The longitudinal key 4 is arranged in a direction perpendicular to the axis of the cylinder body, and the axial key 5 is arranged in a direction the same as the axis of the cylinder body. Other components and connection methods are the same as those of the fifth embodiment.

[0027] In combination with the description of specific embodiments four to six, considering that the end of the cylinder body needs to extend into the exhaust volute and there is a lack of working space for installing bolts, the present application uses a key connection to replace the traditional bolt connection. While ensuring accurate positioning and reliable connection, it can also effectively prevent the end of the cylinder body from angling and deformation.

[0028] Specific implementation method seven: Combination Figure 1 This embodiment is described. The difference between this embodiment and the sixth embodiment is that the 2N support rods 3 are evenly divided into two support rod groups, and the two support rod groups are symmetrically arranged along the joint surface of the upper cylinder and the lower cylinder. The upper support rod group is located between the end cylinder body of the upper cylinder and the exhaust volute structure 1, and the lower support rod group is located between the end cylinder body of the lower cylinder and the exhaust volute structure 1. Other components and connection methods are the same as those of the seventh embodiment.

[0029] Specific implementation method eight: Combination Figure 1 This embodiment is described. The difference between this embodiment and the seventh embodiment is that the value range of N is 3 to 5. The other components and connection methods are the same as those of the eighth embodiment.

[0030] Specific implementation method nine: Combination Figure 1 The present embodiment is described in detail. The present embodiment is different from the eighth embodiment in that the axis of the support rod is arranged parallel to the axis of the cylinder body. The other components and connection methods are the same as those of the ninth embodiment.

[0031] The present invention has been disclosed as above with preferred implementation cases, but it is not intended to limit the present invention. Any technician familiar with the profession can make some changes or modifications to equivalent implementation cases with equivalent changes by using the above-disclosed structures and technical contents without departing from the scope of the technical solution of the present invention. However, any simple modifications, equivalent changes and modifications made to the above implementation cases based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

[0032] How it works

[0033] When in use, the present application assembles the various components together according to the connection relationships described in Specific Embodiments 1 to 10. During the operation of the steam turbine, the steam passes through the rear X-stage embedded cylinder structure 2 and enters the exhaust volute structure 1, thereby ensuring the exhaust area while reducing the axial distance. The cooperation of the longitudinal key 4 and the axial key 5 can avoid the angulation and deformation of the embedded structure here while connecting the upper and lower cylinders. The upper and lower half cylinders at the end of the rear X-stage embedded cylinder structure 2 are each provided with 4 support rod designs to ensure the strength of the cantilever structure of the embedded part.

Claims

1. A steam turbine embedded compact exhaust cylinder structure, the exhaust cylinder structure comprising an exhaust volute (1) and a cylinder body, characterized in that: The rear X-stage cylinder structure (2) in the cylinder block extends into the exhaust volute structure (1), and the rear X-stage cylinder structure (2) and the exhaust volute structure (1) are supported by a support unit.

2. The steam turbine embedded compact exhaust cylinder structure according to claim 1, characterized in that: The value range of X in the rear X-stage cylinder structure (2) is 1 to 3.

3. The steam turbine embedded compact exhaust cylinder structure according to claim 2, characterized in that: The support unit comprises 2N support rods (3), N being a positive integer, and the 2N support rods (3) are equidistantly arranged along the circumferential direction between the rear X-stage cylinder structure (2) and the exhaust volute structure (1), and one end of each support rod (3) is welded and fixed to the end of the rear X-stage cylinder structure (2), and the other end of each support rod (3) is welded and fixed to the inner end wall of the exhaust volute structure (1).

4. The steam turbine embedded compact exhaust cylinder structure according to claim 3, characterized in that: The cylinder body is a split structure, and the cylinder body includes an upper cylinder and a lower cylinder. The end cylinder body of the upper cylinder and the end cylinder body of the lower cylinder are spliced ​​and fixed by two key units.

5. The steam turbine embedded compact exhaust cylinder structure according to claim 4, characterized in that: The two key units are symmetrically arranged on the joint surface of the upper cylinder and the lower cylinder along the axis of the cylinder body, and the top of each key unit is embedded in the end cylinder body of the upper cylinder, and the bottom of each key unit is embedded in the end cylinder body of the lower cylinder.

6. The steam turbine embedded compact exhaust cylinder structure according to claim 5, characterized in that: The key unit comprises a longitudinal key (4) and an axial key (5). The longitudinal key (4) has a length extending direction perpendicular to the axis of the cylinder body, and the axial key (5) has a length extending direction which is the same as the axis extending direction of the cylinder body.

7. The steam turbine embedded compact exhaust cylinder structure according to claim 1, characterized in that: The 2N support rods (3) are evenly divided into two support rod groups, and the two support rod groups are symmetrically arranged along the joint surface of the upper cylinder and the lower cylinder. The upper support rod group is located between the end cylinder body of the upper cylinder and the exhaust volute structure (1), and the lower support rod group is located between the end cylinder body of the lower cylinder and the exhaust volute structure (1).

8. The steam turbine embedded compact exhaust cylinder structure according to claim 7, characterized in that: The value range of N is 3 to 5.

9. The steam turbine embedded compact exhaust cylinder structure according to claim 8, characterized in that: The axis of the support rod is arranged parallel to the axis of the cylinder body.

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