A gas turbine and a method for controlling the axial clearance of a rotor and a stator thereof

Abstract

The present application discloses a gas turbine and a method for controlling the axial clearance of its rotor and stator, and relates to the technical field of gas turbines. The gas turbine includes: a rotating shaft; a casing structure, which coincides with the axis of the rotating shaft; the casing structure includes an air intake casing, a compressor casing, a combustion chamber casing and a turbine casing arranged in sequence; a direct current channel is formed at the connection between the compressor casing and the combustion chamber casing; the air intake casing, the combustion chamber casing and the turbine casing are all integrated casings; a support structure is arranged between the rotating shaft and the casing structure, at least for limiting the relative displacement of the rotating shaft and the casing structure along a first direction; the first direction is parallel to the radial direction of the rotating shaft. The present application forms a direct current channel between the compressor casing and the combustion chamber casing, that is, the energy loss of compressed air during the output process is small, and its application in light gas turbines can effectively improve the output efficiency of light gas turbines.

Description

Technical Field

[0001] The present application relates to the technical field of gas turbines, and in particular to a method for controlling the axial clearance of a gas turbine and a rotor and stator thereof. Background Art

[0002] A gas turbine is an internal combustion power machine that uses a continuously flowing gas as a working fluid to drive the turbine to rotate at high speed, converting the energy of the fuel into useful work. It is mainly composed of three major components: a compressor, a combustion chamber, and a turbine. When in use, the gas turbine injects compressed air into the combustion chamber through the compressor. The compressed air reacts with the fuel in the combustion chamber to produce high-temperature combustion gas, which drives the turbine to rotate and perform external work. In other words, the gas turbine uses a simple cycle to convert the chemical energy of the fuel into thermal energy, and then converts part of the thermal energy into mechanical energy.

[0003] A common gas turbine in the prior art is provided with an air intake casing, a compressor casing, a combustion chamber casing and a turbine casing in sequence. The compressed air output by the compressor in such a gas turbine has a flow path as follows: Figure 1 As shown in the path A in , after the reverse flow is formed at the connection between the compressor casing and the combustion chamber casing, it enters the combustion chamber to participate in the combustion. It should be clear that the design of this type of gas turbine is suitable for heavy-duty gas turbines with large output power. For heavy-duty gas turbines, the structural design of the counter-flow single-tube combustion chamber can effectively shorten the length of the gas turbine rotor, thereby making its supporting structure simpler and the total weight smaller. Under the same conditions, the shorter the rotor length, the stronger its rigidity, thereby avoiding the resonance problem caused by the engine operating near the critical speed of its rotor; on the other hand, the use of a counter-flow combustion chamber and a horizontal split-type combustion chamber casing makes on-site maintenance easier. However, the above design is not suitable for light gas turbines. First of all, the output power of light gas turbines is small, and the counter-flow design causes a large energy loss of compressed air, which in turn has a greater impact on the output efficiency of light gas turbines. Secondly, generally speaking, for reasons of assembly and maintainability, heavy-duty gas turbines with counterflow combustion chambers are designed with each casing as a split casing. In order to ensure the rigidity of the split casing, its thickness must be large, resulting in a larger total weight of the gas turbine, which does not meet certain application scenarios where the gas turbine has a smaller weight and a higher power-to-weight ratio. Summary of the invention

[0004] The purpose of the present application is to provide a gas turbine and a method for controlling the axial clearance between the rotor and stator thereof, so as to solve the technical problem that the design of a counter-flow gas turbine is not suitable for a light gas turbine.

[0005] To achieve the above objectives, this application provides the following technical solutions:

[0006] In the first aspect, the present application proposes a gas turbine, which includes: a rotating shaft; a casing structure, which coincides with the axis of the rotating shaft; the casing structure includes an air intake casing, a compressor casing, a combustion chamber casing and a turbine casing arranged in sequence; a direct current channel is formed at the connection between the compressor casing and the combustion chamber casing; the air intake casing, the combustion chamber casing and the turbine casing are all integrated casings; a support structure is arranged between the rotating shaft and the casing structure, at least for limiting the relative displacement of the rotating shaft and the casing structure along a first direction; the first direction is parallel to the radial direction of the rotating shaft.

[0007] As a specific solution in the technical solution of this application, the support structure includes:

[0008] A first bearing is disposed at a first end of the rotating shaft; and the first bearing is connected to the air intake casing;

[0009] The second bearing is disposed at the second end of the rotating shaft; and the second bearing is connected to the casing structure.

[0010] As a specific solution in the technical solution of the present application, the casing structure also includes a supporting casing, which is arranged between the compressor casing and the combustion chamber casing; the supporting structure also includes a bearing casing and a third bearing, the bearing casing is arranged on the inner wall of the supporting casing, the third bearing is arranged on the rotating shaft, and the third bearing is connected to the bearing casing.

[0011] As a specific solution in the technical solution of the present application, the second bearing is connected to the turbine casing, or the second bearing is connected to the bearing casing.

[0012] As a specific solution in the technical solution of this application, the support structure includes:

[0013] The fourth bearing and the fifth bearing are both arranged on the rotating shaft; and the fourth bearing and the fifth bearing are both connected to the air intake casing;

[0014] A stopper is arranged and fixed on the rotating shaft, and the stopper is located between the fourth bearing and the fifth bearing.

[0015] As a specific solution in the technical solution of the present application, the support structure also includes a first gasket, which is arranged and fixed to the rotating shaft; the first gasket is located between the stopper and the rotating shaft.

[0016] As a specific solution in the technical solution of the present application, a second gasket is further provided between the support casing and the combustion chamber casing.

[0017] As a specific solution in the technical solution of the present application, the second gasket includes a first contact portion and a second contact portion; the first contact portion includes a first contact surface in contact with the support casing; the second contact portion includes a second contact surface in contact with the combustion chamber casing; the area of ​​the first contact surface is smaller than the area of ​​the second contact surface.

[0018] In a second aspect, the present application provides a method for controlling the rotor-stator axial clearance of a gas turbine, the method being applied to the gas turbine as described in any one of the first aspects, the method comprising:

[0019] Obtaining a first gap between a compressor stator and a compressor rotor;

[0020] Based on the first gap, obtaining a thickness of the first gasket;

[0021] Based on the thickness of the first gasket, manufacturing the first gasket;

[0022] The first gasket is installed in the gas turbine.

[0023] As a specific solution in the technical solution of the present application, after installing the first gasket in the gas turbine, the method further includes:

[0024] obtaining a second gap between the turbine stator and the turbine rotor;

[0025] Based on the second gap, obtaining a thickness of the second gasket;

[0026] Based on the thickness of the second gasket, manufacturing the second gasket;

[0027] The second gasket is installed in the gas turbine.

[0028] Compared with the prior art, the beneficial effects of this application are:

[0029] This application forms a direct current channel between the compressor casing and the combustion chamber casing, that is, the energy loss of compressed air during the output process is small, and its application in light gas turbines can effectively improve the output efficiency of light gas turbines. In addition, the air intake casing, combustion chamber casing and turbine casing of the gas turbine proposed in this application are all integrated casings. Compared with the split casing, the thickness of the casing can be effectively reduced while meeting the same rigidity requirements, that is, the overall weight of the gas turbine can be reduced, so that the gas turbine design can be further applied to light gas turbines. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a structural schematic diagram of a gas turbine in the prior art;

[0031] Figure 2 A schematic diagram of the structure of a gas turbine proposed in an embodiment of the present application;

[0032] Figure 3 A schematic diagram of the structure of another gas turbine proposed in an embodiment of the present application;

[0033] Figure 4 A cross-sectional schematic diagram of a second gasket proposed in an embodiment of the present application;

[0034] Figure 5 It is a plan schematic diagram of a split-type receiver (the axis of the receiver is perpendicular to the paper surface);

[0035] Figure 6 It is a plan schematic diagram of the one-piece receiver (the axis of the receiver is perpendicular to the paper surface).

[0036] In the figure: 1, air intake casing; 2, compressor casing; 21, compressor stator; 22, compressor rotor; 3, support casing; 31, bearing casing; 32, third bearing; 4, combustion chamber casing; 5, turbine casing; 51, turbine stator; 52, turbine rotor; 6, rotating shaft; 7, first bearing; 71, stopper; 72, fourth bearing; 73, fifth bearing; 74, first gasket; 8, second bearing; 9, second gasket; 91, first contact portion; 92, second contact portion. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0038] It should be noted that, in the description of the present application, the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.

[0039] Furthermore, it should be understood that for the sake of ease of description, the sizes of the various components shown in the drawings are not drawn according to actual proportions. For example, the thickness or width of certain layers may be exaggerated relative to other layers.

[0040] It should be noted that like reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined or described in one drawing, it will not require further detailed discussion and description in the description of the subsequent drawings.

[0041] Before understanding the embodiments of the present application, it should be understood that, due to the complex internal structure of an actual gas turbine, it is difficult for those skilled in the art to clearly see the improvements of the embodiments of the present application if the embodiments are presented according to the actual gas turbine structure. Figures 1 to 3 Only some of the components of the gas turbine are shown, and some of the displayed components are also simplified. For example, in order to simplify the shaft 6, the shaft 6 is drawn as a shaft with equal outer diameters along its axial centerline; in order to simplify the turbine rotor 52, the turbine rotor 52 is drawn as a rectangular strip structure. The simplified schematic diagram of the components above is only a schematic diagram of the position of the component, and does not represent a restriction on the shape and structure of the component. In other words, in the actual production process, the simplified components above can refer to or directly adopt the existing design.

[0042] In order to solve the Figure 1 The gas turbine design shown is not suitable for the technical problem of light gas turbines. The present application proposes a gas turbine, which includes a rotating shaft 6, a casing structure and a supporting structure. Among them, the casing structure coincides with the axis of the rotating shaft 6. The casing structure includes an air intake casing 1, a compressor casing 2, a combustion chamber casing 4 and a turbine casing 5 arranged in sequence, and a direct current channel is formed at the connection between the compressor casing 2 and the combustion chamber casing 4. It should be clear that if a direct current channel is formed at the connection between the compressor casing 2 and the combustion chamber casing 4, the compressed air will not form a backflow at the connection between the compressor casing 2 and the combustion chamber casing 4, that is, as Figure 2 and Figure 3 As shown, the compressed air forms a direct current as shown by path B at the connection between the compressor casing 2 and the combustion chamber casing 4. In an application scenario where the gas turbine output power is relatively small, if the compressed air forms a direct current at the connection between the compressor casing 2 and the combustion chamber casing 4, the total pressure loss of the compressed air is relatively small, that is, the output efficiency of the gas turbine can be improved.

[0043] In this embodiment, the air intake casing 1, the combustion chamber casing 4 and the turbine casing 5 can be configured as split casings. In order to reduce the overall weight of the gas turbine, in a specific embodiment of the present application, the air intake casing 1, the combustion chamber casing 4 and the turbine casing 5 can be configured as an integrated casing. It should be understood that the split casing is Figure 5 As shown in the figure, it is composed of two half rings, which are combined into a circular ring-shaped receiver by bolts or the like when in use. Figure 6 As shown in the figure, it is an integrated structure without any joints in the middle. Compared with the split casing of the same thickness, the integrated casing has greater structural rigidity. In other words, under the condition of meeting certain structural rigidity requirements, the integrated casing can be designed to be much thinner than the split casing, which can significantly reduce the overall weight of the gas turbine.

[0044] It should be clear that during the operation of the gas turbine, the rotating shaft 6 is in a high-speed rotating state. In order to ensure that during the rotation of the rotating shaft 6, the axis of the rotating shaft 6 and the casing structure always coincide, that is, to ensure that the rotating shaft 6 and the casing structure cannot produce relative displacement along the first direction (the first direction is parallel to the radial direction of the rotating shaft 6), a support structure needs to be provided between the rotating shaft 6 and the casing structure. The support structure is at least used to limit the relative displacement of the rotating shaft 6 and the casing structure along the first direction.

[0045] In the embodiments of the present application, the support structure may be any structure that can ensure that the rotating shaft 6 and the casing structure cannot produce relative displacement along the first direction. For example, the support structure in the present application may be as shown in the following embodiments.

[0046] As an embodiment of the present application, the support structure in this embodiment can be Figure 1 The supporting structure is the same as that in FIG. The supporting structure includes a first bearing 7 and a second bearing 8. The first bearing 7 is arranged at the first end of the rotating shaft 6, and the first bearing 7 is connected to the air intake casing 1. The second bearing 8 is arranged at the second end of the rotating shaft 6, and the second bearing 8 is connected to the turbine casing 5. When in use, under the support of the first bearing 7 and the second bearing 8, the rotating shaft 6 can not only rotate freely, but also keep a constant distance from the casing structure.

[0047] It should be clear that compared to Figure 1 In the gas turbine in the improved gas turbine of the embodiment of the present application, the length of the shaft 6 is longer. It is easy to understand that if the length of the shaft 6 is longer, then during the use of the gas turbine, only the fulcrums (that is, the first bearing 7 and the second bearing 8) are set at the first end and the second end of the shaft 6. The longer length of the shaft 6 leads to a longer rotor, which is easy to make it a flexible rotor, which will cause critical speed changes and then cause vibration and other problems, making it difficult to achieve long-term stability of the shaft 6. In order to enable the shaft 6 of the improved gas turbine to be supported stably for a long time, in another embodiment of the present application, the casing structure also includes a support casing 3, and the support casing 3 is arranged between the compressor casing 2 and the combustion chamber casing 4. The support structure also includes a bearing casing 31 and a third bearing 32. The bearing casing 31 is arranged on the inner wall of the support casing 3, the third bearing 32 is arranged on the shaft 6, and the third bearing 32 is connected to the bearing casing 31. When in use, Figure 2As shown, the first bearing 7 , the second bearing 8 and the third bearing 32 can form three fulcrums on the rotating shaft 6 . Compared with two fulcrums, the three fulcrums can provide more stable support for the rotating shaft 6 having a longer length.

[0048] It should be understood that in a gas turbine, it is necessary to set up an oil circuit to supply oil and lubricate bearings and other structures, and it is also necessary to set up an air circuit to supply air and seal bearings and other structures. If a third bearing 32 is added, it is necessary to set up additional oil circuits and air circuits to lubricate and seal the third bearing 32. It is easy to understand that the more oil circuits for lubrication or air circuits for sealing in a gas turbine, the higher the manufacturing cost during production; the higher the control cost during use. In order to add a third bearing 32 without adding oil circuits and air circuits, in another embodiment of the present application, as Figure 3 As shown, the second bearing 8 is connected to the bearing casing 31. When in use, the second bearing 8 and the third bearing 32 can share the same oil circuit and gas circuit. That is, in this embodiment, the third bearing 32 is added without increasing the oil circuit and gas circuit in the gas turbine. That is, the manufacturing cost and control cost of the gas turbine will not be increased.

[0049] It should be clear that in the embodiments of the present application, there is no restriction on the shape and structure of the support casing 3. In one embodiment of the present application, the support casing 3 can be an integrated casing. In order to reduce the flow rate of the compressed air flowing through the support casing 3 and increase the static pressure of the compressed air, so that the airflow can meet the conditions for combustion in the combustion chamber, in another embodiment of the present application, the inner diameter of the support casing 3 increases along the first direction, the first direction is parallel to the axial direction of the rotating shaft 6, and points from the compressor casing 2 to the combustion chamber casing 4 (that is, the flow direction of the compressed air in the support casing 3). It should be clear that since the inner diameter of the support casing 3 increases along the first direction, the speed of the compressed air in the support casing 3 decreases during the flow along the first direction. Compared with compressed air with a higher speed, compressed air with a lower speed has less effect on the stability of combustion inside the combustion chamber casing 4.

[0050] It should be clear that the compressor in the prior art not only includes the compressor casing 2, but also includes Figure 1 The compressor stator 21 and the compressor rotor 22 are shown. The compressor stator 21 is arranged on the compressor casing 2, and the compressor rotor 22 is arranged on the rotating shaft 6. Similarly, in the prior art, the turbine not only includes the turbine casing 5, but also includes the following Figure 1The turbine stator 51 and turbine rotor 52 are shown. The turbine stator 51 is arranged on the turbine casing 5, and the turbine rotor 52 is arranged on the rotating shaft 6. The axial clearance between the compressor stator 21 and the compressor rotor 22 and the axial clearance between the turbine stator 51 and the turbine rotor 52 can be collectively referred to as the rotor-stator axial clearance of the gas turbine; in addition, for this single-shaft gas turbine, the compressor rotor and the turbine rotor are collectively referred to as rotors. When in use, the positions of the compressor stator 21 and the turbine stator 51 remain unchanged, and both are used to guide the airflow; the rotor rotates driven by the gas at the outlet of the combustion chamber and is connected to the outside world through the output end of the rotating shaft 6 to perform work externally.

[0051] The current gas turbine is developing towards high compression ratio and high turbine pre-temperature. On the one hand, the gas turbine is affected by speed changes, temperature loads and aerodynamic loads, the shaft is deformed under load, the casing structure is deformed, the thermal expansion of the shaft and the casing structure is inconsistent, and the excessive rotor-stator axial clearance will lead to poor sealing effect of the airflow channel between the rotor and the stator, reducing the efficiency of the gas turbine. Too small rotor-stator clearance will cause the rotor (such as the compressor rotor 22 or the turbine rotor 52) and the stator (such as the compressor stator 21 or the turbine stator 51) to collide and rub, affecting the safety and reliability of the gas turbine. Therefore, in the production process of the gas turbine, the precise control of the rotor-stator axial clearance is crucial for the gas turbine.

[0052] As can be seen from the foregoing, the smaller the axial clearance between the rotor and stator of the gas turbine is, the better, provided that the thermal expansion is satisfied and the rotor and stator of the gas turbine do not collide and rub. It is easy to understand that during the use of the gas turbine, due to the thrust generated by the high-temperature combustion gas, the rotating shaft 6 will also be subjected to a huge axial force. Since the axial clearance between the rotor and stator of the gas turbine is small, if the rotating shaft 6 is axially displaced under the action of the axial force, it is easy to cause the stator and rotor of the gas turbine to collide and rub.

[0053] In order to prevent the shaft 6 from undergoing axial displacement that is not within the permissible range under the action of the axial force, that is, to prevent the stator and rotor of the gas turbine from rubbing against each other during use, in one embodiment of the present application, the support structure further includes a stopper 71, a fourth bearing 72, and a fifth bearing 73. The fourth bearing 72 and the fifth bearing 73 are both arranged on the air intake casing 1, and the stopper 71 is fixed on the shaft 6. There is a very thin oil film between the stopper 71 and the fourth bearing 72 in the axial direction, and the thickness of the oil film can be ignored. Figure 2 and Figure 3 As shown, the two (i.e., the stopper 71 and the fourth bearing 72) are considered to be in contact. Figure 2 and Figure 3 As shown, the stopper 71 and the fifth bearing 73 can also be regarded as being in contact. Figure 2 and Figure 3As shown, the axial relative positions of the stopper 71, the fourth bearing 72 and the fifth bearing 73 remain fixed, thereby preventing the shaft 6 of the gas turbine from moving in the axial direction, that is, preventing the rotor and stator of the gas turbine from rubbing against each other.

[0054] It should be clear that if the rotor is longer along its axial direction and if the rotor is a multi-section connection structure, the rotor produced based on the same production technology will have a greater cumulative error in the axial direction. If the cumulative error in the axial direction of the shaft is greater, the axial clearance error of the gas turbine will be greater when the gas turbine is assembled.

[0055] In order to avoid that the gap error between the compressor stator 21 and the compressor rotor 22 is large during the installation of the gas turbine, resulting in the axial gap between the compressor stator 21 and the compressor rotor 22 not meeting the design requirements. In one embodiment of the present application, the support structure further includes a first gasket 74, which is disposed between the rotating shaft 6 and the stopper 71. Figure 2 and Figure 3 As shown, in this embodiment, the first gasket 74 is located and fixed between the stopper 71 and the protruding portion of the rotating shaft 6. It is easy to understand that the relative position of the rotating shaft 6 in the axial direction can be adjusted by controlling the thickness of the first gasket 74, thereby accurately controlling the axial clearance between the compressor stator 21 and the compressor rotor 22. Figure 2 As shown, if the compressor rotor 22 is closer to the point C of the compressor stator 21 and farther from the point D of the compressor stator 21, it is only necessary to increase the thickness of the first gasket 74 to ensure that the rotating shaft 6 moves as a whole along its axial direction from the air intake casing 1 to the turbine casing 5, that is, to ensure that the distances between the compressor rotor 22 and the points C and D of the compressor stator 21 (that is, the axial clearance between the compressor rotor 22 and the compressor stator 21) meet the accuracy requirements. If the compressor rotor 22 is farther from the point C of the compressor stator 21 and closer to the point D of the compressor stator 21, it is only necessary to reduce the thickness of the first gasket 74 to ensure that the distances between the compressor rotor 22 and the points C and D of the compressor stator 21 meet the accuracy requirements.

[0056] In order to avoid the axial clearance between the turbine stator 51 and the turbine rotor 52 not meeting the design requirements during the installation of the gas turbine, in one embodiment of the present application, a second gasket 9 is further provided between the support casing 3 and the combustion chamber casing 4. It is easy to understand that in this embodiment, the clearance between the turbine stator 51 and the turbine rotor 52 can be precisely controlled by controlling the thickness of the second gasket 9. Figure 2As shown, if the turbine rotor 52 is closer to the point E of the turbine stator 51 and farther from the point F of the turbine stator 51, it is only necessary to make the thickness of the second gasket 9 thinner to ensure that the distances (i.e., the gap) between the turbine rotor 52 and the points E and F of the turbine stator 51 meet the requirements. If the turbine rotor 52 is farther from the point E of the turbine stator 51 and closer to the point F of the turbine stator 51, it is only necessary to make the thickness of the second gasket 9 thicker to ensure that the distances (i.e., the gap) between the turbine rotor 52 and the points E and F of the turbine stator 51 meet the requirements.

[0057] In the embodiment of the present application, there is no restriction on the shape and structure of the second gasket 9. For example, the second gasket 9 may be in the shape of a ring with varying inner and outer diameters along the axial direction (for example, a ring with an isosceles trapezoidal cross section, or a ring with a cross section of Figure 4 The cross section shown is a "T"-shaped ring), or it can be a ring with constant inner and outer diameters along the axial direction.

[0058] It should be clear that if a second gasket 9 is provided between the support casing 3 and the combustion chamber casing 4, the second gasket 9 not only needs to have the function of adjusting the gap, but also needs to have a sealing function to prevent the high-temperature and high-pressure gas inside the combustion engine from overflowing from the gap at the connection between the support casing 3 and the combustion chamber casing 4, thereby affecting the working efficiency and on-site safety of the gas turbine. In order to improve the sealing function of the second gasket 9, in one embodiment of the present application, the second gasket 9 includes a first contact portion 91 and a second contact portion 92, the first contact portion 91 includes a first contact surface in contact with the support casing 3, and the second contact portion 92 includes a second contact surface in contact with the combustion chamber casing 4. The area of ​​the first contact surface is smaller than the area of ​​the second contact surface. It should be clear that the area of ​​the first contact surface is smaller than the area of ​​the second contact surface (for example, the second gasket 9 with an isosceles trapezoidal or "T"-shaped cross section proposed in the foregoing), that is, the weight of the second gasket 9 along its axial direction must be uneven. When the gas turbine is in use, it is placed horizontally, that is, the axis of the gas turbine is parallel to the horizontal plane. That is to say, when the gas turbine is in use, the axis of the second gasket 9 is also parallel to the horizontal plane. Since the weight of the second gasket 9 along its axial direction is uneven, the second gasket 9 has a tendency to tilt under the action of gravity, and this tendency to tilt will cause the first contact surface to form a resistance force with the support casing 3, and will also cause the second contact surface to form another resistance force with the combustion chamber casing 4. The formation of the above two resistance forces is conducive to sealing the gap between the support casing 3 and the combustion chamber casing 4.

[0059] In order to improve the sealing performance, it is generally necessary to perform precision machining on the first contact surface and the second contact surface of the gasket 9, the surface of the support casing 3 that cooperates with the first contact surface, and the surface of the combustion chamber casing 4 that cooperates with the second contact surface of the gasket 9. As can be seen from the foregoing, the embodiment of the present application adjusts the thickness of the second gasket 9 to accurately control the gap between the turbine stator 51 and the turbine rotor 52. It should be clear that it is relatively easy to reduce the thickness of the second gasket 9, while it is relatively difficult to increase the thickness of the second gasket 9. Therefore, in the embodiment of the present application, the thickness of the second gasket 9 can be made to exceed or be equal to the maximum design thickness. When in use, it is only necessary to reduce the thickness of the second gasket 9. In a specific embodiment of the present application, such as Figure 4 As shown, the second gasket 9 can be a "T"-shaped gasket. Figure 4 As shown, the first contact portion 91 with a smaller width is more conducive to the thinning operation than the second contact portion 92 with a larger width. After the first contact portion 91 is thinned, the first contact surface is also smaller, that is, the cost of finishing the first contact surface and the surface of the support casing 3 that cooperates with the first contact surface is also lower, which is conducive to reducing production costs.

[0060] It should be clear that, by setting the first gasket 74 and the second gasket 9, the overall precision requirements of the rotating shaft 6 and the casing structure during the production process of the gas turbine can be reduced. The first gasket 74 and the second gasket 9 can be used to adjust the axial clearance of the rotor and stator of the gas turbine to meet the design precision. It is easy to understand that if the overall precision requirements of the rotating shaft 6 and the casing structure during the production process are reduced, the production cost of the rotating shaft 6 and the casing structure can be reduced.

[0061] It should be clear that the gas turbine proposed in this application uses a direct current channel between the compressor casing and the combustion chamber casing, that is, the energy loss of compressed air during the output process is small, and its application in light gas turbines can effectively improve the thermal efficiency of light gas turbines. In addition, the air intake casing, combustion chamber casing and turbine casing of the gas turbine proposed in this application are all integrated casings, which can effectively reduce the thickness of the casing while maintaining the same rigidity, that is, reduce the overall weight of the gas turbine, so that the gas turbine design can be further applied to light gas turbines.

[0062] It should be clear that the gas turbine designed in this application is a gas turbine between a heavy-duty gas turbine and an aero-derivative gas turbine. The gas turbine of this structure is mainly used in consideration of the large demand for gas turbines in offshore platform application scenarios, and the offshore platform has stringent requirements on the weight of the gas turbine, that is, the gas turbine cannot be too thick and heavy. Taking into account the requirements on the weight of the gas turbine, except for the compressor casing which is a vertical split casing, the other casings of the gas turbine are all one-piece casings. The advantage of this structure is that the compressor casing is a vertical split casing, which is convenient for assembly and maintenance; and the other casings are all one-piece casings, which can meet the rigidity requirements while meeting the requirements of smaller weight. It should be clear that the application scenario of the embodiment of the present application applied to the offshore platform should not be understood as limiting the application scenario of the gas turbine of the present application, that is, the gas turbine of the present application can be applied to any application scenario that has stringent requirements on the weight of the gas turbine.

[0063] It should be clear that the gas turbine embodiment proposed in the present application can accurately control the axial clearance between the rotor and stator of the gas turbine when a direct current channel is used between the compressor casing and the combustion chamber casing. If a direct current channel is used between the compressor casing and the combustion chamber casing, the energy loss of the compressed air during the output process is small, and the output efficiency of the light gas turbine can be effectively improved in the application scenario of the light gas turbine. And this method is applicable to gas turbines whose air intake casing, combustion chamber casing and turbine casing are all integrated casings. It is easy to understand that, compared with the split casing, the integrated casing can effectively reduce the thickness of the casing while maintaining the same strength, that is, reduce the overall weight of the gas turbine.

[0064] After introducing the embodiment of the gas turbine proposed in the present application, the following introduces an embodiment of a method for controlling the rotor-stator axial clearance of a gas turbine proposed in the present application. Specifically, the method is applied to the gas turbine as described in any one of the above embodiments, and the method includes steps S100 to S400.

[0065] Step S100: Acquire a first gap between the compressor stator 21 and the compressor rotor 22.

[0066] It should be understood that measuring and obtaining the axial clearance (ie, the first clearance) between the compressor stator 21 and the compressor rotor 22 during the production process of the gas turbine is a mature technology and will not be elaborated here.

[0067] Step S200: Based on the first gap, obtain the thickness of the first gasket 74 .

[0068] As can be seen from the foregoing, the size of the first gap can be adjusted by the thickness of the first gasket 74. Therefore, the thickness of the first gasket 74 when the first gap is within the standard range can be calculated by the current size of the first gap, which will not be elaborated here.

[0069] Step S300 : manufacturing the first gasket 74 based on the thickness of the first gasket 74 .

[0070] The production of gaskets of fixed size is a mature technology and will not be described in detail here.

[0071] Step S400: Install the first gasket 74 in the gas turbine.

[0072] It should be clear that the first gasket 74 can only adjust the axial clearance between the compressor stator 21 and the compressor rotor 22 to within the standard range, and cannot adjust the axial clearance between the turbine stator 51 and the turbine rotor 52 at the rear end of the gas turbine to within the standard range. In order to adjust the axial clearance between the turbine stator 51 and the turbine rotor 52 to within the standard range, in one embodiment of the present application, in step S400, after installing the first gasket 74 in the gas turbine, the method further includes steps S500 to S800.

[0073] Step S500 : obtaining a second gap between the turbine stator 51 and the turbine rotor 52 .

[0074] It should be understood that measuring and obtaining the axial clearance (ie, the second clearance) between the turbine stator 51 and the turbine rotor 52 during the production process of the gas turbine is a mature technology and will not be elaborated here.

[0075] Step S600: Based on the second gap, obtain the thickness of the second gasket 9.

[0076] As can be seen from the foregoing, the size of the second gap can be adjusted by the thickness of the second gasket 9. Therefore, the thickness of the second gasket 9 when the second gap is within the standard range can be calculated by the current size of the second gap, which will not be elaborated here.

[0077] Step S700 : manufacturing the second gasket 9 based on the thickness of the second gasket 9 .

[0078] The production of fixed-size gaskets is a mature technology and will not be described in detail here.

[0079] Step S800: Install the second gasket 9 in the gas turbine.

[0080] It should be clear that the embodiment of the method for controlling the axial clearance of the rotor and stator of a gas turbine proposed in the present application can accurately control the axial clearance of the rotor and stator of the gas turbine when a direct current channel is used between the compressor casing and the combustion chamber casing. If a direct current channel is used between the compressor casing and the combustion chamber casing, the energy loss of the compressed air during the output process is small, and the output efficiency of the light gas turbine can be effectively improved in the application scenario of the light gas turbine. And this method is applicable to gas turbines whose air intake casing, combustion chamber casing and turbine casing are all integrated casings. It is easy to understand that, compared with the split casing, the integrated casing can effectively reduce the thickness of the casing while maintaining the same strength, that is, reduce the overall weight of the gas turbine.

[0081] Although the embodiments of the present application have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A gas turbine, characterized in that: include: A rotating shaft (6); The casing structure coincides with the axis of the rotating shaft (6); the casing structure comprises an air intake casing (1), a compressor casing (2), a combustion chamber casing (4) and a turbine casing (5) which are arranged in sequence; a direct current channel is formed at the connection between the compressor casing (2) and the combustion chamber casing (4); the air intake casing (1), the combustion chamber casing (4) and the turbine casing (5) are all integrated casings; A support structure, arranged between the rotating shaft (6) and the casing structure, and at least used to limit the relative displacement of the rotating shaft (6) and the casing structure along a first direction; the first direction is parallel to the radial direction of the rotating shaft (6); A supporting casing (3); the supporting casing (3) is arranged between the compressor casing (2) and the combustion chamber casing (4); A second gasket (9) is also provided between the support casing (3) and the combustion chamber casing (4); The second gasket (9) comprises a first contact portion (91) and a second contact portion (92); the first contact portion (91) comprises a first contact surface in contact with the support casing (3); the second contact portion (92) comprises a second contact surface in contact with the combustion chamber casing (4); the area of ​​the first contact surface is smaller than the area of ​​the second contact surface.

2. The gas turbine according to claim 1, characterized in that The support structure comprises: A first bearing (7) is disposed at a first end of the rotating shaft (6); and the first bearing (7) is connected to the air intake casing (1); A second bearing (8) is disposed at the second end of the rotating shaft (6); and the second bearing (8) is connected to the casing structure.

3. The gas turbine according to claim 2, characterized in that The support structure further comprises a bearing casing (31) and a third bearing (32); the bearing casing (31) is arranged on the inner wall of the support casing (3); the third bearing (32) is arranged on the rotating shaft (6); and the third bearing (32) is connected to the bearing casing (31).

4. The gas turbine according to claim 3, characterized in that The second bearing (8) is connected to the turbine casing (5), or the second bearing (8) is connected to the bearing casing (31).

5. The gas turbine according to claim 3 or 4, characterized in that The support structure comprises: The fourth bearing (72) and the fifth bearing (73) are both arranged on the rotating shaft (6); and the fourth bearing (72) and the fifth bearing (73) are both connected to the air intake casing (1); A stopper (71) is arranged and fixed on the rotating shaft (6), and the stopper (71) is located between the fourth bearing (72) and the fifth bearing (73).

6. The gas turbine according to claim 5, characterized in that The supporting structure further comprises a first gasket (74), wherein the first gasket (74) is arranged on and fixed to the rotating shaft (6); the first gasket (74) is located between the stopper (71) and the rotating shaft (6).

7. A method for controlling the axial clearance of a rotor and stator of a gas turbine, characterized in that: The method is applied to the gas turbine according to any one of claims 1 to 6, and the method comprises: Obtaining a first gap between a compressor stator (21) and a compressor rotor (22); Based on the first gap, obtaining the thickness of the first gasket (74); Manufacturing the first gasket (74) based on the thickness of the first gasket (74); The first gasket (74) is installed in the gas turbine.

8. The method for controlling the rotor-stator axial clearance of a gas turbine according to claim 7, characterized in that: After installing the first gasket (74) in the gas turbine, the method further comprises: Obtaining a second gap between the turbine stator (51) and the turbine rotor (52); Based on the second gap, obtaining the thickness of the second gasket (9); Based on the thickness of the second gasket (9), manufacturing the second gasket (9); The second gasket (9) is installed in the gas turbine.

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