High-temperature high-pressure steam turbine inner cylinder

Abstract

The utility model discloses a high temperature high pressure steam turbine inner cylinder, and lower connecting lug portion is equipped with limit hole at the junction with upper connecting lug portion, limit hole is communicated with first through -hole upwards, limit hole is communicated with second through -hole downwards, and the through -type stud is penetrated first through -hole, limit hole and second through -hole, and the through -type stud has the protruding limit portion that cooperates with limit hole and two screw rod portions that are respectively located the upper and lower ends of limit portion, and the end portion of screw rod portion that stretches out first through -hole or second through -hole is equipped with the screw thread and is connected with the nut screw thread, wherein the limit portion outer diameter of through -type stud is greater than the outer diameter of screw rod portion, the aperture of second through -hole is less than the aperture of limit hole, and the limit portion of through -type stud is limited with limit hole and cooperates to limit the downward movement of through -type stud. The utility model can install the through -type stud in advance before putting lower cylinder body into steam cylinder, then put lower cylinder body into steam cylinder, then install rotor and upper cylinder body, fasten the upper and lower halves of inner cylinder together, make installation more convenient and fast.

Description

Technical Field

[0001] This utility model relates to the field of steam turbine technology, and in particular to a high-temperature and high-pressure steam turbine inner cylinder. Background Technology

[0002] A steam turbine is a rotary power machine that converts the thermal energy of steam into mechanical energy. Its core working principle is to use high-temperature, high-pressure steam to impact the blades, causing the rotor to rotate and perform work. When the steam parameters of the steam turbine increase, in order to reduce the steam pressure on the outer cylinder, the original steam chamber (or nozzle chamber) is upgraded to an inner cylinder, forming a nested structure of an inner cylinder and an outer cylinder. The inner cylinder bears the strong stress generated by the high-temperature, high-pressure steam. During turbine installation, the lower cylinder body of the inner cylinder must first be installed into the lower half of the cylinder before installing the upper cylinder body, and then the upper half of the cylinder is installed. To withstand the strong stress generated by the high-temperature, high-pressure steam, the upper and lower halves of the inner cylinder are connected by studs. There are usually two types: inserted double-ended stud connection and through-type double-ended stud connection. In comparison, the through-type double-ended stud connection has higher strength. However, when using the through-type double-ended stud connection, the nut that needs to be screwed in after the lower cylinder body of the inner cylinder is inserted into the lower half of the cylinder is between the lower half of the cylinder and the lower inner cylinder, making the installation of the through-type stud very difficult. Utility Model Content

[0003] To solve the above-mentioned technical problems, the purpose of this utility model is to provide a high-temperature and high-pressure steam turbine inner cylinder, which can install through-type studs in advance before the lower cylinder body is put into the steam cylinder, and then put the lower cylinder body into the lower half of the steam cylinder, making the installation more convenient and quick.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A high-temperature, high-pressure steam turbine inner cylinder includes an upper cylinder body and a lower cylinder body. The upper cylinder body has an upper connecting lug on its circumference near the lower cylinder body, and the lower cylinder body has a lower connecting lug on its circumference near the upper cylinder body. The upper connecting lug has a first through hole, and the lower connecting lug has a second through hole corresponding to the first through hole. The lower connecting lug has a limiting hole at its joint with the upper connecting lug. The limiting hole communicates upward with the first through hole and downward with the second through hole. A through-type stud passes through the first through hole, the limiting hole, and the second through hole. The through-type stud has a protruding limiting part that mates with the limiting hole and two screw parts located at the upper and lower ends of the limiting part, respectively. The end of the screw part extending out of the first or second through hole is threaded and threadedly connected to a nut. The outer diameter of the limiting part of the through-type stud is larger than the outer diameter of the screw part, and the diameter of the second through hole is smaller than the diameter of the limiting hole. In this way, the limiting part of the through-type stud and the limiting hole limit each other, thereby restricting the downward movement of the through-type stud.

[0006] In some embodiments, the outer peripheral shape of the limiting part enables the limiting part to be restricted from rotating by the limiting hole after it is installed in the limiting hole.

[0007] In some embodiments, a portion of the outer peripheral cross-sectional shape of the limiting portion is an arc shape, and another portion is a straight line.

[0008] In some embodiments, the outer peripheral cross-sectional shape of the limiting portion is polygonal or elliptical.

[0009] In some embodiments, the outer peripheral cross-sectional shape of the limiting portion is a triangle, a square, a rectangle, or a regular hexagon.

[0010] In some embodiments, a chamfer is provided at the connection between the limiting part and the screw part.

[0011] In some embodiments, the outer diameter of the threaded end of the threaded portion of the through-type stud is larger than the outer diameter of the other portions of the threaded portion.

[0012] In some embodiments, the diameter of the first through hole is smaller than the diameter of the limiting hole.

[0013] In some embodiments, the cross-sectional shape and size of the first through hole are the same as those of the second through hole.

[0014] In some embodiments, the nut at the top of the upper connecting ear is spot-welded to the upper cylinder body, and the nut at the bottom of the lower connecting ear is spot-welded to the lower cylinder body.

[0015] This utility model has the following beneficial effects:

[0016] This utility model relates to an inner cylinder for a medium-high temperature and high-pressure steam turbine. A limiting hole is provided at the lower connecting lug, and a protruding limiting part of the through-type stud is provided, matching the shape of the limiting hole. This allows the limiting part of the through-type stud to be limited by the limiting hole, eliminating the need to manually hold the through-type stud in the installation position during installation. This ensures that the through-type stud will not fall into the lower cylinder half during installation. The through-type stud can be installed before the lower cylinder body is placed into the upper cylinder half, followed by the installation of the rotor and upper cylinder body. Then, the nuts installed on the upper cylinder body are tightened according to the torque or elongation, securing the upper and lower halves of the inner cylinder together, making installation more convenient and quick. The outer periphery of the limiting part has a rotation limiting structure, ensuring that the through-type stud will not rotate when the nut at the bottom of the lower connecting lug is tightened. Attached Figure Description

[0017] Figure 1 This is one of the structural schematic diagrams of the inner cylinder of a high-temperature and high-pressure steam turbine.

[0018] Figure 2 This is the second schematic diagram of the inner cylinder of a high-temperature, high-pressure steam turbine.

[0019] Figure 3It is a partial sectional view of the upper and lower connecting ears (without through studs).

[0020] Figure 4 It is a partial sectional view of the upper and lower connecting ears (with through studs).

[0021] Figure 5 yes Figure 4 Sectional view at point AA.

[0022] Figure 6 This is one of the three-dimensional diagrams of a through-type stud.

[0023] Figure 7 This is the second 3D view of a through-type stud.

[0024] Figure 8 This is a schematic diagram of a through-type stud.

[0025] 1. Upper cylinder block; 2. Lower cylinder block; 3. Upper exhaust pipe; 31. Upper connecting lug; 311. First through hole; 4. Lower exhaust pipe; 41. Lower connecting lug; 411. Second through hole; 412. Limiting hole; 5. Through-type stud; 51. Limiting part; 52. Nut; 53. Screw part; 54. End. Detailed Implementation

[0026] The embodiments of this utility model are described in detail below. It should be emphasized that the following description is merely exemplary and not intended to limit the scope and application of this utility model.

[0027] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component. Furthermore, a connection can be used for fixing, coupling, or communication.

[0028] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0029] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0030] refer to Figures 1-5 The high-temperature and high-pressure steam turbine inner cylinder of this utility model embodiment includes: an upper cylinder body 1 and a lower cylinder body 2. The upper cylinder body 1 is provided with an upper connecting lug 31 on the circumference near the lower cylinder body 2, and the lower cylinder body 2 is provided with a lower connecting lug 41 on the circumference near the upper cylinder body 1. The upper connecting lug 31 is provided with a first through hole 311, and the lower connecting lug 41 is provided with a second through hole 411 corresponding to the first through hole 311. The lower connecting lug 41 is provided with a limiting hole 412 at the joint with the upper connecting lug 31. The limiting hole 412 communicates upward with the first through hole 311 and downward with the second through hole 411. A through-type stud 5 passes through the first through hole 311. The through-hole 311, the limiting hole 412, and the second through-hole 411 are provided. The through-type stud 5 has a protruding limiting part 51 that cooperates with the limiting hole 412 and two screw parts 53 located at the upper and lower ends of the limiting part 51, respectively. The end of the screw part 53 extending out of the first through-hole 311 or the second through-hole 411 is provided with a thread 54 and is threadedly connected to the nut 52. The outer diameter of the limiting part 51 of the through-type stud 5 is larger than the outer diameter of the screw part 53, and the diameter of the second through-hole 411 is smaller than the diameter of the limiting hole 412. In this way, the limiting part 51 of the through-type stud 5 cooperates with the limiting hole 412 to limit the downward movement of the through-type stud 5.

[0031] refer to Figure 5 In this embodiment and some other embodiments, the outer peripheral shape of the limiting part 51 allows the limiting part 51 to be restricted from rotating by the limiting hole 412 after it is installed into the limiting hole 412. This design prevents the through-type stud 5 from rotating during the tightening of the nut 52, facilitating quick and easy installation. For example, in this embodiment, part of the outer peripheral cross-sectional shape of the limiting part 51 is arc-shaped, and the other part is straight; that is, the cylindrical limiting part 51 has a vertical plane on its outer periphery, and the limiting hole 412 has a mating surface that matches the shape of the vertical plane. The vertical plane can be stopped by the mating surface, preventing it from rotating circumferentially. In other embodiments, the outer peripheral cross-sectional shape of the limiting part 51 is one of a polygon, ellipse, triangle, square, rectangle, or regular hexagon.

[0032] In this embodiment and some other embodiments, a chamfer is provided at the connection between the limiting part 51 and the screw part 53 to avoid stress concentration and improve the connection strength.

[0033] In this embodiment and some other embodiments, the outer diameter of the end with the thread 54 on the threaded portion 53 of the through-type stud 5 is larger than the outer diameter of the other parts of the threaded portion 53.

[0034] refer to Figure 4 In this embodiment and some other embodiments, the diameter of the first through hole 311 is smaller than the diameter of the limiting hole 412, which can limit the upper end of the limiting part 51, so that the stud can remain stable even when the nut 52 of the lower cylinder 2 is loose. In this embodiment, the cross-sectional shape and size of the first through hole 311 are the same as those of the second through hole 411, which facilitates through hole processing.

[0035] In this embodiment and some other embodiments, the nut 52 at the top of the upper connecting ear 31 is spot-welded to the upper cylinder 1, and the nut 52 at the bottom of the lower connecting ear 41 is spot-welded to the lower cylinder 2. This makes the stud and cylinder a single unit, resulting in greater strength.

[0036] The installation steps of the high-temperature and high-pressure steam turbine inner cylinder in this embodiment are as follows: Install through-type studs 5 at the lower connecting lug 41 of the lower cylinder body, so that the limiting part 51 is embedded in the limiting hole 412. Then, tighten the bottom fixing nut 52 appropriately and spot weld it to prevent loosening, so that the through-type studs 5 and the lower cylinder body 2 become a whole. Then, put the lower cylinder body 2 into the lower half of the cylinder. After that, install the rotor and the upper cylinder body 1. Then, tighten the nut 52 installed on the upper cylinder body 1 according to the torque or elongation. Finally, spot weld the nut 52 of the upper cylinder body 1 to prevent loosening, and fasten the upper and lower halves of the inner cylinder together.

[0037] In this embodiment, to facilitate the installation of through-type studs in the inner cylinder of a high-temperature and high-pressure steam turbine, a limiting part 51 with an anti-rotation function is designed near the middle position of the through-type stud 5. The outer circumferential shape of the limiting part 51 allows it to be circumferentially stopped by the limiting hole 412. The limiting part 51 and the special countersunk hole 412 in the lower cylinder body 2 are fitted together to prevent the through-type stud 5 from falling into the cylinder during installation. There is no need to manually hold the through-type stud 5 in the installation position. When the nut 52 at the bottom of the lower connecting ear 41 is tightened, the limiting part 51 is circumferentially stopped by the limiting hole 412, preventing the through-type stud 5 from rotating. The entire installation process is convenient and quick, greatly facilitating the installation of through-type studs.

[0038] The above description, in conjunction with specific / preferred embodiments, provides a further detailed explanation of the present invention and should not be construed as limiting the specific implementation of the present invention to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the protection scope of the present invention. In the description of this specification, the reference to terms such as "an embodiment," "some embodiments," "preferred embodiment," "example," "specific example," or "some examples," etc., indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the described specific features, structures, materials, or characteristics can be combined in any suitable manner in one or more embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples. Although embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations may be made herein without departing from the scope of protection of the patent application.

Claims

1. A high-temperature, high-pressure steam turbine inner cylinder, characterized in that, include: The upper cylinder (1) and the lower cylinder (2) are provided with an upper connecting lug (31) on the circumference near the lower cylinder (2) and a lower connecting lug (41) on the circumference near the upper cylinder (1). The upper connecting lug (31) is provided with a first through hole (311) and the lower connecting lug (41) is provided with a second through hole (411) corresponding to the first through hole (311). The lower connecting lug (41) is provided with a limiting hole (412) at the joint with the upper connecting lug (31). The limiting hole (412) communicates upward with the first through hole (311) and downward with the second through hole (411). A through-type stud (5) passes through the first through hole (311) and the limiting hole (411). 12) The through-hole (411) has a protruding limiting part (51) that cooperates with the limiting hole (412) and two screw parts (53) located at the upper and lower ends of the limiting part (51). The end of the screw part (53) extending out of the first through hole (311) or the second through hole (411) is provided with a thread (54) and is threaded to the nut (52). The outer diameter of the limiting part (51) of the through-hole (5) is larger than the outer diameter of the screw part (53), and the diameter of the second through hole (411) is smaller than the diameter of the limiting hole (412). In this way, the limiting part (51) of the through-hole (5) cooperates with the limiting hole (412) to limit the downward movement of the through-hole (5).

2. The high-temperature and high-pressure steam turbine inner cylinder as described in claim 1, characterized in that, The outer periphery shape of the limiting part (51) allows the limiting part (51) to be restricted from rotating by the limiting hole (412) after it is installed into the limiting hole (412).

3. The high-temperature and high-pressure steam turbine inner cylinder as described in claim 2, characterized in that, The outer periphery cross-sectional shape of the limiting part (51) is partly arc-shaped and partly straight.

4. The high-temperature and high-pressure steam turbine inner cylinder as described in claim 2, characterized in that, The outer periphery cross-sectional shape of the limiting part (51) is polygonal or elliptical.

5. The high-temperature and high-pressure steam turbine inner cylinder as described in claim 2, characterized in that, The outer periphery cross-sectional shape of the limiting part (51) is a triangle, a square, a rectangle or a regular hexagon.

6. The high-temperature and high-pressure steam turbine inner cylinder as described in claim 1, characterized in that, The connection between the limiting part (51) and the screw part (53) is chamfered.

7. The high-temperature and high-pressure steam turbine inner cylinder as described in claim 1, characterized in that, On the threaded part (53) of the through-type stud (5), the outer diameter of the end with the thread (54) is larger than the outer diameter of the other parts of the threaded part (53).

8. The high-temperature and high-pressure steam turbine inner cylinder as described in claim 1, characterized in that, The diameter of the first through hole (311) is smaller than the diameter of the limiting hole (412).

9. The high-temperature and high-pressure steam turbine inner cylinder as described in claim 8, characterized in that, The cross-sectional shape and size of the first through hole (311) are the same as those of the second through hole (411).

10. The high-temperature and high-pressure steam turbine inner cylinder as described in claim 1, characterized in that, The nut (52) at the top of the upper connecting ear (31) is spot welded to the upper cylinder (1), and the nut (52) at the bottom of the lower connecting ear (41) is spot welded to the lower cylinder (2).

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