Sealed casing and steam turbine

Abstract

The invention discloses a sealed casing and a steam turbine. The casing is assembled by stacking the casings one by one from the bottom, and a good seal is achieved through the action of gravity in cooperation with a flexible rubber ring, thereby constructing a cavity for accommodating the steam turbine, thereby achieving the effect of improving the sealing performance of the casing and solving the problem that the traditional axial installation method is difficult to tighten. An annular groove and a clamping foot are provided at two joints of the lower casing, the upper casing and the top casing. The clamping foot is clamped in the clamping groove to achieve horizontal limitation, and the vertical limitation can be achieved by cooperating with its own gravity, so that the top casing is firmly fixed on the upper casing, and the upper casing is firmly fixed on the lower casing. Moreover, under the action of gravity, the three casings can be pressed and matched, and the cavity in the casing is isolated from the outside world in cooperation with the sealing ring at the gap, thereby improving the sealing performance of the entire cavity.

Description

Technical Field

[0001] The present application relates to the field of steam turbines, and more particularly to a sealed casing and a steam turbine. Background Art

[0002] A steam turbine is an external combustion rotary machine that can convert steam thermal energy into mechanical work. After the steam from the boiler enters the steam turbine, it passes through a series of annular nozzles and moving blades in turn, converting the steam thermal energy into mechanical energy for the rotation of the turbine rotor. Steam undergoes energy conversion in different ways in the steam turbine, forming steam turbines with different working principles.

[0003] The inventors found that due to the large volume of the main shaft and blades of the steam turbine, the volume of the casing used to protect them is also large, and axial multi-section splicing installation is usually adopted. However, when the tightening force is applied axially, the multi-section splicing structure has multiple gaps in sequence, and the gap position is difficult to be well sealed, resulting in air leakage in the turbine casing and energy loss; the casing is in an atmosphere of high-temperature steam for a long time, and the humid environment and high temperature will cause rust inside the casing, causing weak points in the casing structure; when the casing is assembled again, steel wire ropes are often used to directly tie the casing components, which is not only difficult to bundle and dismantle, but the steel wire ropes will also wear the mating surfaces of the casing, resulting in the problem of loose fitting. Summary of the invention

[0004] The purpose of this application is to address the defects of the prior art and provide a sealed casing and a steam turbine. The casing is assembled by stacking them one by one from the bottom up, and a good seal is achieved through the action of gravity and a flexible rubber ring to construct a cavity to accommodate the steam turbine, thereby improving the sealing of the casing and solving the problem that the traditional axial installation method is difficult to tighten.

[0005] The first object of the present application is to provide a sealed housing, which adopts the following technical solutions:

[0006] It includes a lower shell, an upper shell and a top shell which are connected in sequence from bottom to top, and the three together form a cavity, and the cavity is used to accommodate the main shaft and blades of the steam turbine. A first groove is provided on the top surface of the lower shell, and a first clamping foot is provided on the bottom surface of the upper shell. The first clamping foot and the first groove are engaged to realize the connection between the upper shell and the lower shell. A second groove is provided on the top surface of the upper shell, and a second clamping foot is provided on the bottom surface of the top shell. The second clamping foot and the second groove are engaged to realize the connection between the top shell and the lower shell. The first groove and the second groove are both annular, and rubber rings are provided on both sides of their openings. The rubber rings seal the cavity under the pressure of the upper shell and the top shell.

[0007] Furthermore, the lower shell includes a lower cavity with a top opening, the upper shell includes a channel with top and bottom openings, the bottom opening of the channel is connected to the lower cavity, the top shell cooperates with the upper shell to seal the top opening of the channel, the top opening of the lower shell is located inside the inner ring of the first annular groove, and the top opening of the upper shell channel is located inside the inner ring of the second annular groove, thereby achieving sealing of the cavity.

[0008] Furthermore, a lifting ring is installed on the upper shell body, which is used to hang a lifting device externally to drive the upper shell body to move. The outer surface and the channel of the upper shell body are both installed with lifting rings.

[0009] Furthermore, at least two hooks are provided on the top shell body, and the hooks are used to connect an external lifting device to drive the top shell body to move.

[0010] Furthermore, a heat dissipation hole is provided on the side wall of the lower shell, and the heat dissipation hole is used for heat exchange between the cavity and the outside of the sealed casing to reduce the temperature in the cavity.

[0011] Furthermore, a moisture-proof plate is attached to the inner wall of the cavity to reduce the humidity in the casing.

[0012] Furthermore, a cooling device is provided in the lower shell body, and the cooling device includes a circulation pipeline, a refrigerant, a circulation pump and a refrigerator. The circulation pump and the refrigerator are connected to the circulation pipeline, and the refrigerant flows in the circulation pipeline. The cooling device is used to absorb the heat in the cavity and discharge it to the outside of the sealed casing through the refrigerator.

[0013] Furthermore, the circulation pipeline is arranged in the side wall of the lower shell and passes through the heat dissipation holes, so as to absorb the heat in the heat dissipation holes and discharge it outside the sealed casing through the refrigerator.

[0014] The second purpose of the present application is to provide a steam turbine adopting the following technical solution.

[0015] The steam turbine comprises the sealed casing as described above, a main shaft and blades matched on the main shaft. The main shaft is installed between the lower casing and the upper casing through a bearing, and the blades matched on the main shaft are located in the cavity.

[0016] Compared with the prior art, the advantages and positive effects of this application are:

[0017] (1) An annular groove and a clamping foot are provided at two joints of the lower shell, the upper shell and the top shell. The clamping foot is clamped in the clamping groove to achieve horizontal limitation. The vertical limitation can be achieved by cooperating with its own gravity, so that the top shell is firmly fixed on the upper shell, and the upper shell is firmly fixed on the lower shell. In addition, under the action of gravity, the three shells can be pressed and matched. The sealing ring at the gap can isolate the cavity in the casing from the outside, thereby improving the sealing of the entire cavity.

[0018] (2) A cooling device is provided inside the casing. During the use of the steam turbine, the heat of the steam turbine can be dissipated, the temperature of the steam turbine can be reduced, and the aging of the casing caused by long-term heat can be avoided. In addition, the temperature can be reduced and the humidity in the cavity can be reduced by using a moisture-proof plate, which can effectively improve the environment of the fan blades and the inner wall materials of the cavity, so that they are in a low-temperature and dry state, reduce the probability of rust, reduce the maintenance frequency, and effectively reduce the occurrence of weak points;

[0019] (3) The hook installed on the outer wall of the casing makes it convenient for users to lift the upper casing and the casing top during installation and splicing, avoiding the traditional method of lifting by binding with steel wire ropes, which can effectively avoid the problem of inaccurate matching caused by damage to the interface by steel wire ropes;

[0020] (4) The heat generated by the steam turbine will come into contact with the heat pipe at the heat dissipation hole. The heat pipe has a lower temperature, which neutralizes the hot air, increases the contact area between the heat pipe and the high temperature environment, and increases the heat dissipation rate of the steam turbine. After the water temperature rises, it flows back to the cooling box to cool down again, and the cooling is repeated. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings in the specification, which constitute a part of the present application, are used to provide further understanding of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute improper limitations on the present application.

[0022] Figure 1 This is a schematic diagram of the overall structure of the steam turbine of Example 1 of the present application;

[0023] Figure 2 This is a schematic diagram of the structure of the lower housing of Example 1 of the present application;

[0024] Figure 3 This is a schematic diagram of the cooperation between the groove and the clamping foot of Example 1 of the present application.

[0025] Among them: 1. lower shell, 2. heat dissipation pipe, 3. moisture-proof plate, 4. bearing, 5. main shaft, 6. blade, 7. upper shell, 8. lifting ring, 9. clamping foot, 10. rubber ring, 11. top shell, 12. hook, 13. refrigerator, 14. circulation pump, 15. heat dissipation hole. DETAILED DESCRIPTION

[0026] It should be noted that the following detailed descriptions are illustrative and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs.

[0027] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "include" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or their combinations;

[0028] For the convenience of description, if the words "up", "down", "left" and "right" appear in this application, they only indicate that they are consistent with the up, down, left and right directions of the drawings themselves, and do not limit the structure. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on this application.

[0029] Terminology explanation section: The terms "install", "connect", "connect", "fixed" and the like in this application should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be an internal connection between two elements, or an interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0030] As introduced in the background technology, the main shaft and blades of the prior art steam turbine are relatively large in size, which leads to a relatively large volume of the casing used to protect them. Axial multi-section splicing is usually used for installation. However, when the tightening force is applied axially, the multi-section splicing structure has multiple gaps in sequence, and it is difficult to seal the gaps well, resulting in air leakage in the turbine casing and energy loss. The casing is exposed to a high-temperature steam atmosphere for a long time. The humid environment and high temperature will cause rust inside the casing, resulting in weak points in the casing structure. When the casing is assembled again, steel wire ropes are often used to directly tie the casing components. Not only is it difficult to tie and dismantle, the steel wire ropes will also wear the mating surfaces of the casing, resulting in a loose fit. In response to the above technical problems, the present application proposes a sealed casing and a steam turbine.

[0031] Example 1

[0032] In a typical implementation of the present application, Figure 1-Figure 3 As shown, a steam turbine equipped with a sealed casing is proposed.

[0033] The steam turbine comprises a sealed casing, a main shaft 5 and blades 6 fitted on the main shaft. The main shaft is installed between a lower casing and an upper casing via a bearing 4, and the blades fitted on the main shaft are located in the cavity.

[0034] Of course, when the main shaft and the sealed housing are matched through the bearing, the sealing of the bearing position needs to be ensured. The sealing of the bearing position is a common sealing part in this field. Therefore, technical personnel in this field are capable of setting the corresponding sealing structure according to needs, and the specific sealing structure will not be elaborated.

[0035] The sealed casing comprises a lower shell 1, an upper shell 7 and a top shell 11 which are connected in sequence from bottom to top, and the three together form a cavity, and the cavity is used to accommodate the main shaft and blades of the steam turbine. A first groove is provided on the top surface of the lower shell, and a first clamping foot is provided on the bottom surface of the upper shell. The first clamping foot and the first groove are engaged to realize the connection between the upper shell and the lower shell. A second groove is provided on the top surface of the upper shell, and a second clamping foot is provided on the bottom surface of the top shell. The second clamping foot and the second groove are engaged to realize the connection between the top shell and the lower shell. The first groove and the second groove are both annular, and rubber rings 10 are provided on both sides of their openings. The rubber rings seal the cavity under the pressure of the upper shell and the top shell.

[0036] Furthermore, a lifting ring 8 is installed on the upper shell body for hanging a lifting device externally to drive the upper shell body to move. Lifting rings are installed on the outer surface and the channel of the upper shell body; at least two hooks 12 are provided on the top shell body, and the hooks are used for connecting a lifting device externally to drive the top shell body to move.

[0037] When assembling the sealed casing, first determine the installation position of the lower casing, fix the lower casing, install the main shaft and blades in the fixed casing, clamp the bearing at the connection, use a traction rope to cooperate with the hook to connect the lifting ring, use a crane to lift the upper casing, align the first clamping foot of the upper casing with the first groove of the lower casing, slowly lower the upper casing, clamp the first clamping foot into the first groove, let the rubber rings 10 on both sides of the groove opening fit tightly, loosen the traction rope on the lifting ring, clamp the traction rope on the hook, perform the same operation, lift the top casing, align the second clamping foot of the top casing with the second groove of the upper casing, slowly lower the top casing, clamp the second clamping foot into the second groove, and let the rubber rings on both sides of the second groove fit tightly on the bottom surface of the top casing, and complete the assembly of the entire sealed casing.

[0038] The lower shell includes a lower cavity with a top opening, and the upper shell includes a channel with top and bottom openings, the bottom opening of the channel is connected to the lower cavity, and the top shell cooperates with the upper shell to seal the top opening of the channel, the top opening of the lower shell is located inside the inner ring of the first annular groove, and the top opening of the upper shell channel is located inside the inner ring of the second annular groove, thereby achieving sealing of the cavity.

[0039] The foot 9 and the groove cooperate to form a ring, which wraps the cavity inside, and cooperates with two rubber rings to seal from the inner and outer rings of the groove respectively, so as to realize the sealing constraint of the cavity;

[0040] Annular grooves and clamping feet are provided at the two joints of the lower shell, the upper shell and the top shell. The horizontal limitation is achieved by clamping the clamping feet in the clamping grooves, and the vertical limitation can be achieved with the help of its own gravity, so that the top shell is firmly fixed on the upper shell, and the upper shell is firmly fixed on the lower shell. Moreover, the three shells can be pressed together under the action of gravity, and the sealing ring at the gap can isolate the cavity in the casing from the outside world, thereby improving the sealing of the entire cavity.

[0041] Furthermore, a heat dissipation hole 15 is provided on the side wall of the lower shell, and the heat dissipation hole is used for heat exchange between the cavity and the outside of the sealed casing to reduce the temperature in the cavity; a moisture-proof plate 3 is attached to the inner wall of the cavity to reduce the humidity in the casing.

[0042] It should be pointed out that the heat dissipation holes opened here are blind holes, which can shorten the distance between the cavity and the outside world, thereby reducing the path length of heat transfer, improving the heat dissipation while not affecting the sealing of the cavity; the moisture-proof plate is made of existing materials that can absorb water vapor and droplets in the air, and is installed on the inner wall of the cavity by snapping or gluing, thereby avoiding interference with the blades.

[0043] Furthermore, a cooling device is also provided in the lower shell, and the cooling device includes a circulation pipeline, a refrigerant, a circulation pump 14 and a refrigerator 13. The circulation pump and the refrigerator are connected to the circulation pipeline, and the refrigerant flows in the circulation pipeline. The cooling device is used to absorb the heat in the cavity and discharge it to the outside of the sealed casing through the refrigerator; the circulation pipeline is arranged in the side wall of the lower shell and passes through the heat dissipation holes, and is used to absorb the heat in the heat dissipation holes and discharge it to the outside of the sealed casing through the refrigerator.

[0044] The circulation pipeline is composed of multiple sections of heat dissipation pipes 2. The refrigerator receives a refrigerant with a higher temperature, cools it down, and outputs it to the circulation pump through the heat dissipation pipe. The circulation pipe provides driving force to push the refrigerant to circulate along the heat dissipation pipe, absorb the heat in the heat dissipation holes, and then input the refrigerant with a higher temperature into the refrigerator. The heat generated by the refrigerator during the refrigeration process is discharged to the outside of the cavity, thereby realizing a rapid exchange of heat in the cavity with the outside world and achieving rapid cooling.

[0045] The refrigerator here can use an existing compressor in combination with a condenser casing. Of course, other refrigeration methods can also be used as long as the temperature of the refrigerant medium can be reduced and the heat can be discharged from the cavity to the outside. In this embodiment, the refrigerant medium is water.

[0046] The heat generated by the steam turbine will contact the heat pipe at the heat dissipation hole. The heat pipe has a low temperature, which neutralizes the hot air, increases the contact area between the heat pipe and the high temperature environment, and increases the heat dissipation speed of the steam turbine. After the water temperature rises, it flows back to the cooling box to cool down again, and the cooling is repeated;

[0047] A cooling device is installed inside the casing. During the use of the turbine, the heat of the turbine can be dissipated to reduce the temperature of the turbine, thus avoiding aging of the casing caused by long-term heat. In addition, lowering the temperature and using a moisture-proof plate to reduce the humidity in the cavity can effectively improve the environment of the fan blades and the inner wall materials of the cavity, keeping them in a low-temperature and dry state, reducing the chance of rust, reducing the frequency of maintenance, and effectively reducing the occurrence of weak points.

[0048] The above description is only the preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A sealed housing, characterized in that: The invention comprises a lower shell, an upper shell and a top shell connected in sequence from bottom to top, the three of them together form a cavity, the cavity is used to accommodate the main shaft and blades of the steam turbine, a first groove is provided on the top surface of the lower shell, a first clamping foot is provided on the bottom surface of the upper shell, the first clamping foot is engaged with the first groove to realize the connection between the upper shell and the lower shell, a second groove is provided on the top surface of the upper shell, a second clamping foot is provided on the bottom surface of the top shell, the second clamping foot and the second groove are engaged to realize the connection between the top shell and the lower shell, the first groove and the second groove are both annular, and rubber rings are provided on both sides of their openings, and the rubber rings seal the cavity under the pressure of the upper shell and the top shell; The lower shell includes a lower cavity with a top opening, the upper shell includes a channel with top and bottom openings, the bottom opening of the channel is connected to the lower cavity, and the top shell cooperates with the upper shell to block the top opening of the channel; An annular groove and a clamping foot are provided at the two joints of the lower shell, the upper shell and the top shell. The clamping foot is clamped in the clamping groove to achieve horizontal limitation, and the vertical limitation is achieved by cooperating with its own gravity. The top shell is firmly fixed on the upper shell, and the upper shell is firmly fixed on the lower shell. Under the action of gravity, the three shells can be pressed and matched, and the sealing ring at the gap is used to isolate the cavity in the casing from the outside. The upper shell is provided with a lifting ring for hanging a lifting device externally to drive the upper shell to move. The outer surface of the upper shell and the channel are both provided with lifting rings; The side wall of the lower shell is provided with heat dissipation holes, and the heat dissipation holes are used for heat exchange between the cavity and the outside of the sealed casing to reduce the temperature in the cavity.

2. The sealed housing according to claim 1, wherein: At least two hooks are provided on the top shell body, and the hooks are used for connecting an external lifting device to drive the top shell body to move.

3. The sealed housing according to claim 1, wherein: A moisture-proof plate is attached to the inner wall of the cavity to reduce the humidity in the casing.

4. The sealed housing according to claim 1, wherein: A cooling device is also provided in the lower shell, and the cooling device includes a circulation pipeline, a refrigerant, a circulation pump and a refrigerator. The circulation pump and the refrigerator are connected to the circulation pipeline, and the refrigerant flows in the circulation pipeline. The cooling device is used to absorb the heat in the cavity and discharge it to the outside of the sealed casing through the refrigerator.

5. The sealed housing according to claim 4, characterized in that: The circulation pipeline is arranged in the side wall of the lower shell and passes through the heat dissipation hole, and is used for absorbing the heat in the heat dissipation hole and discharging it outside the sealed shell through the refrigerator.

6. A steam turbine, characterized in that: Comprising a sealed housing as described in any one of claims 1-5.

7. The steam turbine according to claim 6, characterized in that The steam turbine also includes a main shaft and blades matched on the main shaft. The main shaft is installed between the lower shell and the upper shell through a bearing, and the blades matched on the main shaft are all located in the cavity.

Images