WO2017113258A1

WO2017113258A1 - Gas turbine, sealing cover, and manufacturing method thereof

Info

Publication number: WO2017113258A1
Application number: PCT/CN2015/100003
Authority: WO
Inventors: Guo Feng Chen; Rui Chun DUAN; Chang Peng LI; Zhi Qi YAO; Hui Wen ZHOU
Original assignee: Siemens Aktiengesellschaft
Priority date: 2015-12-30
Filing date: 2015-12-30
Publication date: 2017-07-06

Abstract

A sealing cover (20) used for a gas turbine (100). The gas turbine (100) comprises at least one turbine disk (143), and the sealing cover (20) is used to cover the turbine disk (143). A side wall (22a) of the sealing cover (20) is provided with a first air hole (222) and a second air hole (223). A spacing is formed between the first air hole (222) and the second air hole (223). A cooling passage (226) and a plurality of ribs (225) are provided within the sealing cover (20). The cooling passage (226) is in communication with the first air hole (222) and the second air hole (223), and the plurality of ribs (225) are disposed within the cooling passage (226) or outside the cooling passage (226). In addition, the plurality of ribs (225) are formed within a weight reduction cavity. A gas turbine (100) and a manufacturing method of a sealing cover (20) are also provided. The sealing cover (20) helps to improve working performance of the gas turbine (100).

Description

GAS TURBINE, SEALING COVER, AND MANUFACTURING METHOD THEREOF

BACKGROUND Technical Field

The present invention relates to the field of gas turbine technologies, and in particular, to a gas turbine, a sealing cover for covering a turbine disk of a gas turbine, and a manufacturing method thereof.

Related Art

A gas turbine is a rotary power machine that uses air flowing continuously as a working medium and that converts thermal energy to mechanical work. The gas turbine generally includes three main components: a compressor, a combustor, and a turbine. At work, the compressor inhales air from an external atmosphere environment, and compresses the air by using an axial-flow compressor to increase pressure of the air, where at the same time, a temperature of the air also increases correspondingly. The compressed air is pressurized into the combustor and a mixture of the air and injected fuel burns to generate high temperature and high pressure gas. Then, the high temperature and high pressure gas enters the turbine and then does work by means of expansion, to push the turbine to drive the compressor and an externally loaded rotor to rotate together at a high speed, so that it is implemented that mechanical energy of gaseous or fluid fuel is partially converted to mechanical work, and electric work is output.

To achieve relatively high power generation efficiency, the turbine works under very high temperature and pressure. Turbine blades and stationary blades of the turbine are usually made of high-temperature materials, for example, Ni-based alloy materials or Co-based alloy materials. Outer surfaces of the turbine blade and the stationary blade are further coated with thermal barrier coatings (TBC) , and the thermal barrier coating may prevent the turbine blade and the stationary blade from being damaged by hot air. To reduce production costs, in normal cases, a material of a turbine disk of the turbine is different from the materials of the turbine blade and the stationary blades, where the turbine disk is generally made of ferrous material. To prevent the turbine disk from being damage by hot air, the turbine disk needs to be covered by a sealing cover.

The sealing cover achieves two functions: in one aspect, the sealing cover may block hot air for the turbine disk, which prevents the turbine disk from being damaged by the hot air； in the other aspect, the sealing cover may prevent the turbine from cooling air used for cooling the turbine disk； therefore, the turbine runs normally.

At work, the sealing cover rotates together with the turbine disk at a high speed, and due to weight of the sealing cover, the sealing cover is subjected to the action of a relatively large centrifugal force. If the sealing cover does not have better mechanical strength, the sealing cover is deformed and then thrown away during the rotation, which may accordingly cause damage to core components of the turbine. To improve mechanical performance of the sealing cover, the sealing cover may be properly made thicker. However, when the sealing cover is thicker, the centrifugal force exerted from the sealing cover is larger, or the sealing cover affects normal flow of air within the turbine； therefore, a thickness of the sealing cover is usually controlled within several millimeters.

Referring to FIG. 1, an existing sealing cover 10 is provided, where the sealing cover 10 covers a turbine disk 101, and a turbine blade 102 is installed on the turbine disk 101. There is a gap 103 between he sealing cover 10 and the turbine disk 101, and cooling air may be leaded into the gap 103, to cool the turbine disk 101. However, in most cases, the sealing cover 10 has a relatively complex structure, and cooling air flows out of a rotor is shielded by some components and cannot freely arrive at a position, near the turbine blade 102, of the turbine disk 101. Therefore, the turbine disk 101 at the position cannot be effectively cooled, so that performance of the gas turbine is affected.

SUMMARY

In view of this, an objective of the present invention is to propose a gas turbine, a sealing cover, and a manufacturing method thereof, so that the gas turbine can have better working performance.

The present invention provides a sealing cover used for a gas turbine, where the gas turbine includes at least one turbine disk, and the sealing cover is used to cover the turbine disk. A side wall of the sealing cover is provided with a first air hole and a second air hole, where there is a spacing between the first air hole and the second air hole； and a cooling passage and a plurality of ribs are provided within the sealing cover, where the cooling passage is in communication with the first air hole and the second air hole, and the plurality of ribs is disposed within the cooling passage or outside the cooling passage.

In an exemplary embodiment of the sealing cover, the plurality of ribs is disposed outside the cooling passage, a weight reduction cavity is further provided within the sealing cover, the weight reduction cavity is separated from the cooling passage by using a strengthening bar, and the plurality of ribs is disposed within the weight reduction cavity.

In an exemplary embodiment of the sealing cover, two ends of each rib are separately fixedly disposed on opposite inner side walls of the weight reduction cavity.

In an exemplary embodiment of the sealing cover, the plurality of ribs includes a plurality of first ribs, a plurality of second ribs, and a plurality of third ribs, and the first ribs, the second ribs, and the third ribs are alternately disposed.

In an exemplary embodiment of the sealing cover, the plurality of ribs is disposed as a grid shape within the cooling passage.

In an exemplary embodiment of the sealing cover, the cooling passage extends along a length direction of the sealing cover.

The present invention further proposes a manufacturing method of a sealing cover used for a gas turbine, where the manufacturing method includes the following steps: processing the sealing cover by using a 3D printing technology； forming a first air hole and a second air hole on a side wall of the sealing cover by using the 3D printing technology, where there is a spacing between the first air hole and the second air hole； and further forming a cooling passage and a plurality of ribs within the sealing cover by using the 3D printing technology, where the cooling passage is in communication with the first air hole and the second air hole, and the plurality of ribs is disposed within the cooling passage or outside the cooling passage.

In an exemplary embodiment of the manufacturing method of a sealing cover, the manufacturing method further includes the following steps: printing the sealing cover along a length direction of the sealing cover, and then performing heat treatment on the sealing cover.

In an exemplary embodiment of the manufacturing method of a sealing cover, a powder material used to shape the sealing cover is a nickel-chromium-iron alloy.

The present invention further proposes a gas turbine, where the gas turbine includes any sealing cover described above.

In an exemplary embodiment of the gas turbine, the gas turbine further includes a rotor and a plurality of turbine blades, where the turbine disk is disposed on the rotor, the turbine blade is installed on the turbine disk, and the sealing cover covers the turbine disk and is located between the rotor and the turbine blade.

In an exemplary embodiment of the gas turbine, the side wall faces the turbine disk, the first air hole is located at a position, near the rotor, of the sealing cover, and the second air hole is located at a position, near the turbine blade, of the sealing cover.

It can be seen from the foregoing technical solutions that in the gas turbine, the sealing cover, and the manufacturing method thereof of the present invention, a cooling passage is provided within a sealing cover, to improve cooling efficiency. A hollow structure and a plurality of ribs are disposed within the sealing cover, so that mechanical strength of the sealing cover can be ensured, and weight of the sealing cover can be reduced to a greater extent； therefore, a centrifugal force problem caused because the sealing cover is excessively heavy is avoided. In addition, the sealing cover is provided with a first air hole and a second air hole, and a cooling passage is in communication with the first air hole and the second air hole, so that cooling air may effectively cool a turbine disk near a turbine blade by using the cooling passage, the first air hole, and the second air hole, which helps to improve of working performance of a gas turbine.

BRIEF DESCRIPTION OF THE DRAWINGS

Other characteristics, features, advantages, and benefits of the present invention become more obvious with reference to the following detailed descriptions of the accompany drawings.

FIG. 1 is a schematic partial diagram of a turbine of a gas turbine in the prior art；

FIG. 2 is a schematic diagram of a gas turbine according to an embodiment of the present invention；

FIG. 3 is a schematic partial diagram of a turbine of the gas turbine shown in FIG. 2；

FIG. 4 is a schematic cross-sectional diagram of a sealing cover shown in FIG. 3；

FIG. 5 is a schematic cross-sectional diagram of the sealing cover, shown in FIG. 4, along a line V-V；

FIG. 6 is a schematic cross-sectional diagram of the sealing cover, shown in FIG. 4, along a line VI-VI； and

FIG. 7 is a schematic diagram of processing equipment that is used for manufacturing the sealing cover shown in FIG. 4.

DETAILED DESCRIPTION

To make the objectives, technical solutions and advantages of the present disclosure more clear, the following further describes the present invention in detail with reference to embodiments.

FIG. 2 is a schematic cross-sectional diagram of a gas turbine according to an embodiment of the present invention. Referring to FIG. 2, the gas turbine 100 in this embodiment includes a compressor 12, a combustor 13, and a turbine 14, where the compressor 12, the combustor 13, and the turbine 14 are sequentially disposed and communicated. A rotor 15 is further provided within the gas turbine 100, and the rotor 15 is through the interior of the compressor 12 and the interior of the turbine 14. The turbine 14 includes a casing 142, at least one turbine disk 143 located within the casing 142, a plurality of turbine blades 144, and a plurality of stationary blades 145. The turbine disk 143 is disposed on the rotor 15. In FIG. 2, there are four turbine disks 143, but the present invention is not limited thereto. The turbine blades 144 are installed on the turbine disk 143, and are annularly arranged. The stationary blade 145 is assembled on an inner side of the casing 142, and the stationary blades 145 and the turbine blades 144 are alternately disposed.

FIG. 3 is a schematic partial diagram of the turbine of the gas turbine shown in FIG. 2. Referring to FIG. 3 together with FIG. 2, the gas turbine 100 further includes a sealing cover 20, where the sealing cover 20 covers the turbine disk 143, and is located between the rotor 15 and the turbine blade 144. The turbine blade 144 is assembled on the turbine disk 143 by using a root 144a, and the other part (which is referred to as a protrusion part of the turbine blade 144) of the turbine blade 144 protrudes out of the turbine disk 143.

FIG. 4 is a schematic cross-sectional diagram of the sealing cover shown in FIG. 3. FIG. 5 is a schematic cross-sectional diagram of the sealing cover, shown in FIG. 4, along a line V-V. Referring to FIG. 4, FIG. 5, and FIG. 2, a side wall 22a of the sealing cover 20 is provided with a first air hole 222 and a second air hole 223, where there is a spacing between the first air hole 222 and the second air hole 223； and a cooling passage 226 and a plurality of ribs 225 are provided within the sealing cover 20, where two ends of the cooling passage 226 are separately in communication with the first air hole 222 and the second air hole 223. The plurality of ribs 225 is disposed within the cooling passage 226 or outside the cooling passage 226. It should be noted that the sealing cover 20 covers the turbine disk 143, a length direction (that is, a Z-axis direction shown in FIG. 4) of the sealing cover 20 extends along a radial direction of the turbine disk 143, and the cooling passage 226 extends along the length direction of the sealing cover 20.

In this embodiment, there are two cooling passages 226, two first air holes 222, and two second air holes 223. The first air hole 222 and the second air hole 223 are separately located at the two ends of the cooling passage 226. Quantities of cooling passages 226, first air holes 222, and second air holes 223 are not limited in the present invention. There may be at least one cooling passage 226, and one end of the cooling passage 226 may be in communication with at least one first air hole 222 or at least one second air hole 223.

The first air hole 222 and the second air hole 223 are located on the same side wall 22a of the sealing cover 20, and when the sealing cover 20 covers the turbine disk 143, the side wall 22a faces the turbine disk 143. The first air hole 222 and the second air hole 223 are oppositely disposed, and may be located on or not on a same straight line. Shapes and sizes of the first air hole 222 and the second air hole 223 are not limited in the present invention. The first air hole 222 is located at a position, near the rotor 15, of the sealing cover 20. The second air hole 223 is located at a position, near the turbine blade 144, of the sealing cover 20； in other words, the second air hole 223 is near a bottom of the protrusion part of the turbine blade 144. Air flowing out of the rotor 15 and passing through the turbine disk 143 may flow into the sealing cover 20 through the first air hole 222, and flow out of the second air hole 223 after flowing through the sealing cover 20, so as to cool a position, near the protrusion part of the turbine blade 144, of the turbine disk 143.

In this embodiment, the plurality of ribs 225 is outside of the cooling passage 226, and a weight reduction cavity 224 is further provided within the sealing cover 20. The weight reduction cavity 224 is separated from the cooling passage 226 by using a strengthening bar 226a. A cross-section of the strengthening bar 226a is in an L-shaped structure, and extends along the Z-axis direction shown in FIG. 4. The plurality of ribs 225 is disposed within the weight reduction cavity 224.

The weight reduction cavity 224 is designed to reduce weight of the sealing cover 20, and the plurality of ribs 225 is disposed within the weight reduction cavity 224, to ensure that the sealing cover has enough mechanical strength. The plurality of ribs 225 includes a plurality of first ribs 225a, a plurality of second ribs 225b, and a plurality of third ribs 225c. The plurality of first ribs 225a is parallel to each other and extends along a first direction. The plurality of second ribs 225b is parallel to each other and extends along a second direction. The plurality of third ribs 225c is parallel to each other and extends along a third direction. The first ribs 225a, the second ribs 225b, and the third ribs 225c are alternately disposed, and two ends of each first rib 225a, each second rib 225b, and each third rib 225c are separately fixedly disposed on opposite inner side walls of the weight reduction cavity 224. Design of the rib 225, which includes a size and an arrangement manner, is not limited to forms listed in the present invention. The rib 225 may be designed according to a structure of a specific sealing cover 20 and mechanical performance, and may be optimized by means of finite element calculation.

FIG. 6 is a schematic cross-sectional diagram of the sealing cover, shown in FIG. 4, along a line VI-VI. Referring to FIG. 6 together with FIG. 4, a thickness of the sealing cover 20 at the line V-V is greater than a thickness of the sealing cover 20 at the line VI-VI. The first rib 225a, the second rib 225b, the third rib 225c, and the strengthening bar 226a are provided within the entire weight reduction cavity 224. The first rib 225a, the second rib 225b, the third rib 225c, and the strengthening bar 226a may be continuously extended along the Z-axis direction shown in FIG. 4, or may be disposed at intervals, for example, the plurality of first ribs 225a is spaced along the Z-axis direction, and the ribs 225 form a grid structure within the weight reduction cavity 224. Still referring to FIG. 4, the side wall 22a of the sealing cover 20 is further provided with a fastening structure 228, and the fastening structure 228 may fasten the sealing cover 20 to the turbine disk 143. However, a shape and a profile of the sealing cover 20 are not limited in the present invention, and the shape and the profile of the sealing cover 20 may be freely designed according to an actual demand.

In another embodiment, the weight reduction cavity 224 may be omitted, and the plurality of ribs 225 is directly disposed within the cooling passage 226, where the plurality of ribs 225 is disposed within the cooling passage 226 in a grid shape. The disposing of the ribs 225 does not affect normal flow of cooling air within the cooling passage 226.

FIG. 7 is a schematic diagram of processing equipment that is used for manufacturing the sealing cover shown in FIG. 4. Referring to FIG. 7, the processing equipment 300 includes a material supply unit 32, a shaping unit 33, and a laser sintering unit 34, where the material supply unit 32 provides powder materials to the shaping unit 33, and the laser sintering unit 34 is used to sinter the powder materials, and make the powder materials to form a profile on the shaping unit 33.

Specifically, the material supply unit 32 includes a supply piston 322, a first cylinder body 323, and a roller 324, where the supply piston 322 is configured in the first cylinder body 323, and may move in a vertical direction along the first cylinder body 323. The powder materials are piled on the supply piston 322. The roller 324 may roll on the powder material, to spread the powder materials on the shaping unit 33. The powder material may be, for example, an Inconel 718 alloy, and the Inconel 718 alloy is a precipitation-hardening nickel-chromium-iron alloy including niobium and molybdenum, and has high strength, desired toughness, and high-temperature performance. The powder material may be further another material having high strength and high-temperature performance.

The shaping unit 33 includes a shaping supply piston 332, a second cylinder body 333, and a shaping portion 334, where the shaping supply piston 332 is configured in the second cylinder body 333, and may move in a vertical direction along the second cylinder body 333； and the shaping portion 334 is fixed to the shaping supply piston 332, and may move in a vertical direction together with the shaping supply piston 332a. The shaping portion 334 is used to bear a to-be-processed component 301.

The laser sintering unit 34 includes a laser 342 and a scanning mirror 343, where the laser 342 is connected to the scanning mirror 343, and may produce a laser beam； and the scanning mirror 343 is used to sinter, by using the laser beam provided by the laser 342, the powder materials to obtain a preset profile.

Referring to FIG. 7 and FIG. 4, a manufacturing method of a sealing cover 20 includes the following steps:

processing the sealing cover 20 by using a 3D printing technology； forming a first air hole 222 and a second air hole 223 on a side wall 22a of the sealing cover 20 by using the 3D printing technology, where there is a spacing between the first air hole 222 and the second air hole 223； and further forming a cooling passage 226 and a plurality of ribs 225 within the sealing cover 20 by using the 3D printing technology, where the cooling passage 226 is in communication with the first air hole 222 and the second air hole 223, and the plurality of ribs 225 is disposed within the cooling passage 226 or outside the cooling passage 226.

Specifically, the 3D printing technology is, for example, selected laser melting (SLM) . The selected laser melting is a rapid prototyping technology of metal powder, and is one of additive manufacturing technologies. During an actual operation, a roller 324 first spreads a layer of powder materials on a shaping portion 334 of a shaping unit 33. A laser sintering unit 34 controls a laser beam to scan the power layer according to a to-be-shaped profile, so that a temperature of powder rises to a melting point, and sinter the power to form a to-be-processed component 301.

When a cross section is sintered, the shaping supply piston 332 goes down, and in this case, the roller 324 evenly spreads a layer of powder materials on the to-be-processed component 301 again and sintering of another cross section starts. The operation is repeated until the sealing cover 20 is completely formed. The powder material used for the sealing cover 20 is a nickel-chromium-iron alloy.

It should be noted that not only the selected laser melting (SLM) , but also another 3D printing technology such as a fused deposition modeling (FDM) technology may be used for the sealing cover 20, but the SLM is used as a preferable solution because the SLM can provide higher mechanical strength, size precision, and workpiece surface quality.

It should be noted that the manufacturing method further includes steps of printing the sealing cover 20 along a length direction of the sealing cover 20, and then performing heat treatment on the sealing cover 20. In a working process of the sealing cover 20, the sealing cover 20 works under a high temperature for a long term, and is subjected to the action of a relatively large centrifugal force along the length direction (that is, a Z-axis direction shown in FIG. 4) , which therefore easily causes creep deformation. Because during the 3D printing, the sealing cover 20 is formed by means of stack-up, proper heat treatment is needed to eliminate an inter-layer structure, to improve mechanical performance, especially, high temperature creep resistance performance of the materials. Specific heat treatment needs to be determined according to a selected printing material and by means of orthogonal experiment. The heat treatment used in the present invention, for example, 0.5 hours to 2 hours of homogenization treatment under a temperature of 1050 degrees Celsius to 1080 degrees Celsius, air cooling to a temperature of 730 degrees Celsius to 790 degrees Celsius, 5 hours to 20 hours of heat preservation, and furnace cooling to a temperature of 630 degrees Celsius to 680 degrees Celsius and 5 hours to 10 hours of heat preservation. Considering that the material after the heat treatment has best high temperature creep resistance performance in the Z-axis direction, the sealing cover 22 may be printed along the Z-axis direction shown in FIG. 4, that is, the length direction of the sealing cover 22a, but the present invention is not limited thereto. In another embodiment, the sealing cover 22 may also be shaped along an X-axis direction or a Y-axis direction shown in FIG. 4.

The gas turbine, the sealing cover, and the manufacturing method thereof of the present invention have the following advantages:

1. In the gas turbine, the sealing cover, and the manufacturing method thereof of the present invention, a cooling passage is provided within a sealing cover, to improve cooling efficiency. A hollow structure and a plurality of ribs are disposed within the sealing cover, so that mechanical strength of the sealing cover can be ensured, and weight of the sealing cover can be reduced to a greater extent； therefore, a centrifugal force problem caused because the sealing cover is excessively heavy is avoided. In addition, the sealing cover is provided with a first air hole and a second air hole, and the cooling passage is in communication with the first air hole and the second air hole, so that cooling air may effectively cool a turbine disk nearby a turbine blade by using the cooling passage, the first air hole, and the second air hole, which helps to improve of working performance of a gas turbine.

2. In an embodiment of the gas turbine, the sealing cover, and the manufacturing method thereof of the present invention, when the ribs are disposed outside the cooling passage, a weight reduction cavity is further provided within the sealing cover, and the plurality of ribs is disposed within the weight reduction cavity. The disposing of the weight reduction cavity may reduce weight of the sealing cover, and at the same time, a strengthening bar enable the sealing cover to have better mechanical performance.

3. In an embodiment of the gas turbine, the sealing cover, and the manufacturing method thereof of the present invention, the plurality of ribs includes a plurality of first ribs, a plurality of second ribs, and a plurality of third ribs, and the first ribs, the second ribs, and the third ribs are alternately disposed, which help to increase strength of the sealing cover.

4. In an embodiment of the gas turbine, the sealing cover, and the manufacturing method thereof of the present invention, the sealing cover is processed by using a 3D printing technology, the sealing cover is printed along a length direction of the sealing cover, and heat treatment is performed on the sealing cover after the printing is completed, which can improve high temperature creep resistance performance of the sealing cover.

5. In an embodiment of the gas turbine, the sealing cover, and the manufacturing method thereof of the present invention, the sealing cover is processed by using a 3D printing technology； therefore, not only the cooling passage and the ribs may be formed within the sealing cover, so that the sealing cover has better strength and performance, but also a thickness and weight of the sealing cover may be controlled within a preset range, so that a centrifugal force problem caused because the sealing cover is excessively heavy is avoided, and air within a turbine normally flows without being affected by excessively thicker sealing cover.

The foregoing descriptions are merely exemplary embodiments of the present invention, but are not intended to limit the present invention. Any modification, equivalent replacement, or improvement made without departing from the spirit and principle of the present invention should fall within the protection scope of the present invention.

Claims

A sealing cover (20) used for a gas turbine (100) , wherein the gas turbine (100) comprises at least one turbine disk (143) ； and the sealing cover (20) is used to cover the turbine disk (143) , wherein

a side wall (22a) of the sealing cover (20) is provided with a first air hole (222) and a second air hole (223) , wherein there is a spacing between the first air hole (222) and the second air hole (223) ； and a cooling passage (226) and a plurality of ribs (225) are provided within the sealing cover (20) , wherein the cooling passage (226) is in communication with the first air hole (222) and the second air hole (223) , and the plurality of ribs (225) is disposed within the cooling passage (226) or outside the cooling passage (226) .
The sealing cover (20) according to claim 1, wherein the plurality of ribs (225) are disposed outside the cooling passage (226) , a weight reduction cavity (224) is further provided within the sealing cover (20) , the weight reduction cavity (224) is separated from the cooling passage (226) by using a strengthening bar (226a) , and the plurality of ribs (225) is disposed within the weight reduction cavity (224) .
The sealing cover (20) according to claim 2, wherein two ends of each rib (225) are separately fixedly disposed on opposite inner side walls of the weight reduction cavity (224) .
The sealing cover (20) according to claim 2, wherein the plurality of ribs (225) comprises a plurality of first ribs (225a) , a plurality of second ribs (225b) , and a plurality of third ribs (225c) , and the first ribs (225a) , the second ribs (225b) , and the third ribs (225c) are alternately disposed.
The sealing cover (20) according to claim 1, wherein the plurality of ribs (225) is disposed as a grid shape within the cooling passage (226) .
The sealing cover (20) according to claim 1, wherein the cooling passage (226) extends along a length direction of the sealing cover (20) .
A manufacturing method of a sealing cover (20) used for a gas turbine (100) , wherein the manufacturing method comprises the following steps:

processing the sealing cover (20) by using a 3D printing technology； forming a first air hole (222) and a second air hole (223) on a side wall (22a) of the sealing cover (20) by using the 3D printing technology, wherein there is a spacing between the first air hole (222) and the second air hole (223) ； and further forming a cooling passage (226) and a plurality of ribs (225) within the sealing cover (20) by using the 3D printing technology, wherein the cooling passage (226) is in communication with the first air hole (222) and the second air hole (223) , and the plurality of ribs (225) is disposed within the cooling passage (226) or outside the cooling passage (226) .
The manufacturing method of a sealing cover (20) according to claim 7, wherein the manufacturing method further comprises the following steps:

printing the sealing cover (20) along a length direction of the sealing cover (20) , and then performing heat treatment on the sealing cover (20) .
The manufacturing method of a sealing cover (20) according to claim 7, wherein a powder material used to shape the sealing cover (20) is a nickel-chromium-iron alloy.
A gas turbine (100) , wherein the gas turbine (100) comprises the sealing cover (20) according to any one of claims 1 to 6.
The gas turbine (100) according to claim 10, wherein the gas turbine (100) further comprises a rotor (15) and a plurality of turbine blades (144) , wherein the turbine disk (143) is disposed on the rotor (15) , the turbine blade (144) is installed on the turbine disk (143) , and the sealing cover (20) covers the turbine disk (143) and is located between the rotor (15) and the turbine blade (144) .
The gas turbine (100) according to claim 11, wherein the side wall (22a) faces the turbine disk (143) , the first air hole (222) is located at a position, near the rotor (15) , of the sealing cover (20) , and the second air hole (223) is located at a position, near the turbine blade (144) , of the sealing cover (20) .