Metal expansion joint for ship steam power system

Abstract

The invention discloses a metal expansion joint for a ship steam power system, and belongs to the field of design of connecting parts for the ship steam power system. The technical problem that on the premise that the large drift diameter and the short installation length are met, an existing corrugated pipe of a traditional structure is large in radial thrust in the working process due to the structure of the corrugated pipe is solved. The multi-layer metal corrugated pipe is arranged between a steam turbine and a condenser, is used for connecting a steam exhaust port of a low-pressure cylinder of the steam turbine and a steam inlet of a throat part of the condenser, and comprises a multi-layer metal corrugated pipe, and the multi-layer metal corrugated pipe is formed by sequentially arranging a plurality of wave-shaped units in the axial direction; a fixed connecting flange is arranged at one end of the multi-layer metal corrugated pipe, and a lap joint flange is arranged at the other end; the lap joint flange is in sealing contact with the turned-over edge of the end of the multi-layer metal corrugated pipe, and the lap joint flange can rotate relative to the axis of the multi-layer metal corrugated pipe. And the radial rigidity of the corrugated pipe is obviously reduced. The invention is used for the connection of the ship steam power system.

Description

Technical Field

[0001] This invention relates to a metal expansion joint for ship steam propulsion systems, belonging to the field of design of connecting components for ship steam propulsion systems. Background Technology

[0002] The main turbine unit is one of the most important pieces of equipment in the secondary loop system of a nuclear power plant. It mainly consists of a turbine, condenser, reducer, expansion joint, and regulating system. The metal expansion joint, located between the turbine and condenser, connects the turbine's low-pressure cylinder exhaust port to the condenser's throat inlet. Its primary function is to absorb axial and radial displacement caused by heating at the turbine exhaust port, ensuring the safe and reliable operation of the unit.

[0003] Due to exhaust parameters and space requirements on the submarine, the expansion joint is made of metal, specifically 321 thin plate. Its most significant characteristic, and also its greatest challenge, lies in its large diameter, short axial length, and high radial thrust. Traditional bellows structures would exhibit extremely high radial stiffness under these conditions. This means that when the expansion joint attempts to absorb radial displacement, it generates an exceptionally large radial thrust. Excessive radial thrust acts directly on the precision turbine exhaust port and condenser inlet through the flange connections, potentially causing overload, deformation, or vibration at the equipment interfaces, seriously threatening the safe operation of the unit.

[0004] In summary, under the premise of meeting the requirements of large diameter and short installation length, the existing traditional corrugated pipe has the technical problem of large radial thrust during operation due to its own structural reasons. Summary of the Invention

[0005] This invention addresses the technical problem of large radial thrust during operation caused by the inherent structural features of conventional bellows, which, while meeting the requirements of large diameter and short installation length, presents a metal expansion joint for ship steam propulsion systems. This joint is positioned between the turbine and the condenser, connecting the turbine's low-pressure cylinder exhaust port and the condenser's throat inlet. The metal expansion joint for ship steam propulsion systems comprises a multi-layered metal bellows, which is composed of multiple corrugated units arranged sequentially along the axial direction.

[0006] One end of the multi-layer metal bellows is equipped with a fixed connection flange, and the other end is equipped with a loose flange;

[0007] The loose flange is in sealing contact with the flanged end of the multilayer metal bellows, and the loose flange can rotate relative to the axis of the multilayer metal bellows.

[0008] As another improvement of the present invention, it also includes a flow guide tube; the flow guide tube is fitted inside a multi-layered metal corrugated pipe.

[0009] As another improvement of the present invention, it also includes a protective cover, lugs, a shipping nut, and a shipping rod. The protective cover 4 is disposed on the outside of the layered metal bellows. The shipping rod is installed on the loose flange by the shipping nut. A plurality of lugs are evenly arranged on the outer wall of the loose flange.

[0010] As another improvement of the present invention, the multilayer metal corrugated pipe is composed of multiple layers of thin metal plates stacked together, with four layers and each layer of thin metal plate having a wall thickness of 0.4 mm.

[0011] As another improvement of the present invention, the number of complete waves distributed along the axial direction of the multilayer metal bellows is 7.

[0012] As another improvement of the present invention, the root diameter of the multilayer metal bellows is 1168 mm.

[0013] As another improvement of the present invention, the waveform parameters of the multilayer metal bellows are as follows: wave height is 65mm and wave pitch is 47mm.

[0014] As another improvement of the present invention, the material of the multilayer metal corrugated pipe is 321 stainless steel sheet.

[0015] As another improvement of the present invention, the inner side of the loose flange is provided with a sealing contact surface that matches the outer contour of the multi-layer metal bellows flange, and the loose flange can rotate around the multi-layer metal bellows flange.

[0016] As another improvement of the present invention, the metal expansion joint is used in the secondary steam system of nuclear-powered ships. Its main function is to absorb the axial and radial displacements caused by thermal deformation of the turbine exhaust port.

[0017] The beneficial effects of this invention are:

[0018] Through specific structural design, including multi-layered, multi-wave, low-wave-height, and low-wave-pitch designs, the radial stiffness of the bellows is significantly reduced while meeting the stringent spatial constraints of a large diameter and short axial length. This effectively controls the radial thrust acting on the turbine and condenser interfaces during operation within a safe range. Manufactured from 321 stainless steel sheet, it can withstand the exhaust temperature, pressure, and other operating parameters of the ship's secondary loop system, ensuring durability and reliability in harsh environments. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a metal expansion joint for a ship's steam power system according to the present invention.

[0020] Figure 2 It is along Figure 1 Schematic diagram of the cross section along line AA.

[0021] Figure 3This is a partial schematic diagram of a multi-layered metal bellows.

[0022] Figure 4 This is a schematic diagram of the assembly of a loose flange and a multi-layer metal bellows. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Specific implementation method one: Combining Figures 1 to 4 This embodiment describes a metal expansion joint for a ship's steam power system. Its characteristic is that it is arranged between the steam turbine and the condenser, connecting the exhaust port of the steam turbine's low-pressure cylinder and the steam inlet of the condenser throat. The metal expansion joint for a ship's steam power system includes a multi-layered metal bellows 2, which is composed of multiple corrugated units arranged sequentially along the axial direction.

[0025] One end of the multi-layer metal corrugated pipe 2 is provided with a fixed flange 1, and the other end is provided with a loose flange 3;

[0026] The loose flange 3 is in sealing contact with the flange at the end of the multilayer metal bellows 2, and the loose flange 3 can rotate relative to the axis of the multilayer metal bellows 2.

[0027] Through a specific structure and multi-layered, multi-wave design, the radial stiffness of the bellows is significantly reduced while meeting the stringent space constraints of a large diameter and short axial length. This effectively controls the radial thrust acting on the turbine and condenser interfaces during operation within a safe range. The design of the slip-on flange facilitates installation and alignment in confined spaces, improving assembly adaptability. Specifically designed for the connection between the turbine and condenser, it can simultaneously absorb axial and radial displacements, enhancing the stability and safety of unit operation.

[0028] Specific Implementation Method Two: Combining Figures 1 to 4 This embodiment differs from specific embodiment one in that it also includes a guide tube 5; the guide tube 5 is fitted inside the multi-layer metal corrugated pipe 2. Other components and connection methods are the same as in specific embodiment one or two.

[0029] Specific implementation method three: Combining Figures 1 to 4This embodiment differs from specific embodiment one in that it further includes a protective cover 4, lugs 8, a transport nut 6, and a transport rod 7. The protective cover 4 is disposed on the outside of the corrugated metal pipe; the transport rod 7 is mounted on the slip-on flange 3 via the transport nut 6; and multiple lugs 8 are evenly distributed on the outer wall of the slip-on flange 3. This design facilitates transportation and installation. Other components and connection methods are the same as in any one of specific embodiments one to three.

[0030] Specific implementation method four: Combination Figures 1 to 4 This embodiment differs from specific embodiment one in that the multi-layer metal bellows 2 is composed of four layers of stacked thin metal plates, each with a wall thickness of 0.4 mm. Through this specific structure and multi-layer design, the radial stiffness of the bellows is significantly reduced while meeting the stringent spatial constraints of a large diameter and short axial length, thereby controlling the radial thrust acting on the turbine and condenser interfaces during operation within a safe range. Other components and connection methods are the same as in any one of specific embodiments one to three.

[0031] Specific Implementation Method Five: Combining Figures 1 to 4 This embodiment differs from specific embodiment one in that the multi-layer metal bellows 2 has seven complete waves distributed axially. Through a specific structure and multi-wave design, the radial stiffness of the bellows is significantly reduced while meeting the stringent spatial constraints of a large diameter and short axial length, thereby controlling the radial thrust acting on the turbine and condenser interfaces during operation within a safe range. Other components and connection methods are the same as in any one of specific embodiments one through four.

[0032] Specific Implementation Method Six: Combination Figures 1 to 4 This embodiment differs from specific embodiment one in that the corrugated root diameter of the multilayer metal corrugated pipe 2 is 1168 mm. Other components and connection methods are the same as any one of specific embodiments one through five.

[0033] Specific implementation method seven: Combination Figures 1 to 4 This embodiment differs from specific embodiment one in that the waveform parameters of the multilayer metal bellows 2 have a wave height of 65mm and a wave pitch of 47mm. Using "small wave height, small wave pitch" waveform parameters reduces radial thrust while ensuring displacement compensation capability. Other components and connection methods are the same as any one of specific embodiments one through six.

[0034] Specific implementation method eight: Combination Figures 1 to 4This embodiment differs from specific embodiment one in that the multilayer metal corrugated pipe 2 is made of 321 stainless steel sheet. It balances corrosion resistance and flexibility, making it suitable for the high-temperature and high-humidity environment of ship steam propulsion systems. Other components and connection methods are the same as any one of specific embodiments one through seven.

[0035] Specific Implementation Method Nine: Combining Figures 1 to 4 This embodiment differs from specific embodiment one in that the inner side of the loose flange 3 has a sealing contact surface that mates with the outer contour of the flange of the multi-layer metal bellows 2, allowing the loose flange 3 to rotate around the flange of the multi-layer metal bellows 2. This facilitates installation and alignment in confined spaces, improving assembly adaptability. Other components and connection methods are the same as in any one of specific embodiments one through eight.

[0036] Specific Implementation Method Ten: Combining Figures 1 to 4 This embodiment differs from specific embodiment one in that the metal expansion joint is used in the secondary steam system of a nuclear-powered ship. Its main function is to absorb the axial and radial displacements caused by thermal deformation of the turbine exhaust port. Other components and connection methods are the same as any one of specific embodiments one through nine.

[0037] Combination Figures 1 to 4 Explanation of the working principle of this invention:

[0038] Through specific structural design, including multi-layered, multi-wave, low-wave-height, and low-wave-pitch designs, the radial stiffness of the bellows is significantly reduced while meeting the stringent spatial constraints of a large diameter and short axial length. This effectively controls the radial thrust acting on the turbine and condenser interfaces during operation within a safe range. Manufactured from 321 stainless steel sheet, it can withstand the exhaust temperature, pressure, and other operating parameters of the ship's secondary loop system, ensuring durability and reliability in harsh environments.

[0039] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A metal expansion joint for a ship's steam power system, characterized in that It is arranged between the steam turbine and the condenser, and is used for connecting the exhaust port of the low-pressure cylinder of the steam turbine and the steam inlet port of the throat of the condenser, and the metal expansion joint for the steam power system of a ship comprises a multilayer metal bellows (2) which is composed of a plurality of wave units arranged in sequence along the axial direction. One end of the multilayer metal bellows (2) is provided with a fixed flange (1), and the other end is provided with a loose flange (3). The loose flange (3) is in sealing contact with the folded edge of the end of the multilayer metal bellows (2), and the loose flange (3) can rotate relative to the axis of the multilayer metal bellows (2).

2. A metal expansion joint for use in a marine steam power system according to claim 1, characterized in that It further comprises a flow guide cylinder (5) which is sleeved in the multilayer metal bellows (2).

3. A metal expansion joint for use in a marine steam power system according to claim 1, characterized in that It further comprises a protective cover (4), lugs (8), a shipping nut (6) and a shipping rod (7), the protective cover (4) is arranged outside the multilayer metal bellows, the shipping rod (7) is installed on the loose flange (3) through the shipping nut (6), and the outer wall of the loose flange (3) is uniformly provided with a plurality of lugs (8).

4. A metal expansion joint for use in a marine steam power system according to claim 1, characterized in that The multilayer metal bellows (2) is composed of a plurality of layers of metal thin plates, and the number of layers is 4, and the wall thickness of each layer of metal thin plate is 0.4mm.

5. A metal expansion joint for use in a marine steam power system according to claim 1, wherein The number of complete waves of the multilayer metal bellows (2) distributed along the axial direction is 7.

6. A metal expansion joint for use in a marine steam power system according to claim 1, wherein The wave root diameter of the multilayer metal bellows (2) is 1168mm.

7. A metal expansion joint for use in a marine steam power system according to claim 1, wherein In the wave parameters of the multilayer metal bellows (2), the wave height is 65mm, and the wave distance is 47mm.

8. A metal expansion joint for use in a marine steam power system according to claim 1, characterized in that The material of the multilayer metal bellows (2) is 321 stainless steel thin plate.

9. A metal expansion joint for use in a marine steam power system according to claim 1, wherein The inner side of the loose flange (3) is provided with a sealing contact surface matched with the outer contour of the folded edge of the multilayer metal bellows (2), and the loose flange (3) can rotate around the folded edge of the multilayer metal bellows (2).

10. A metal expansion joint for use in a marine steam power system according to claim 1, wherein The metal expansion joint is used for the secondary loop steam system of a nuclear power ship, and mainly functions to absorb the axial displacement and radial displacement of the exhaust port of the steam turbine caused by thermal deformation.

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