Gas turbine sealing tape welding method

Abstract

A gas turbine sealing tape welding method belongs to the technical field of gas turbines and comprises the following steps: determining the thickness of brazing filler metal according to the shape of a sealing tape; the sealing tape, the fiber metal plate and the brazing filler metal are correspondingly assembled and fixed together; the fixed sealing tape, the fiber metal plate and the brazing filler metal are assembled on a tool; and putting the assembled tool into a high-temperature vacuum brazing furnace, and performing vacuum brazing on the sealing tape and the fiber metal plate according to process conditions. According to the method, high-temperature brazing of the sealing tape of the heavy-duty gas turbine is achieved, the welding effect of the sealing tape of the heavy-duty gas turbine is guaranteed, and it is guaranteed that internal parts of the gas turbine can work normally in the high-temperature and high-pressure environment when the method is used for sealing the gas turbine.

Description

Technical Field

[0001] The invention relates to a welding method, in particular to a gas turbine sealing belt welding method, and belongs to the technical field of gas turbines. Background Art

[0002] Heavy-duty gas turbine sealing tape is mainly used in the front and rear seals of the transition section of heavy-duty gas turbines. The front and rear seals of the transition section of heavy-duty gas turbines play a vital role in heavy-duty gas turbines. The front seal is usually located at the outlet of the combustion chamber of the gas turbine to prevent the gas from leaking out of the transition section and to ensure that the gas is effectively guided to the turbine section before entering the transition section. The rear seal is located between the transition section and the turbine section to prevent the gas from leaking or flowing back when entering the turbine, while ensuring efficient turbine operation. High-temperature brazing of heavy-duty gas turbine sealing tape is a very critical process, which is usually used to ensure that the internal components of the gas turbine can work normally under high temperature and high pressure environments. There is currently no experience in the production and manufacturing of related products.

[0003] In summary, how to weld the heavy-duty gas turbine sealing belt by high-temperature brazing to ensure efficient turbine operation has become an urgent problem to be solved by technicians in this field. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides a gas turbine sealing belt welding method to reduce gas leakage and improve the efficiency of the gas turbine.

[0005] S1. Determine the thickness of the solder according to the shape of the sealing tape;

[0006] S2. Assemble and fix the sealing tape, fiber metal plate and solder together accordingly;

[0007] S3, assembling the fixed sealing tape, fiber metal plate and solder onto the tooling;

[0008] S4. Put the assembled tooling into a high-temperature vacuum brazing furnace, and vacuum braze the sealing tape and the fiber metal plate according to the process conditions.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] The method of the present application realizes high-temperature brazing of the sealing belt of a heavy-duty gas turbine, which not only ensures the welding effect of the sealing belt of the heavy-duty gas turbine, but also ensures the dimensions of the front and rear seals of the transition section. It can ensure that the internal components of the gas turbine can work normally under high temperature and high pressure environments. The method solves the manufacturing application of high-temperature brazing of the sealing belt of such heavy-duty gas turbines, ensures product quality, and improves production efficiency.

[0011] The technical solution of the present invention is further described below in conjunction with the accompanying drawings and embodiments: BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Schematic diagram of tooling combined with the present application method

[0013] Figure 2 for Figure 1 AA view;

[0014] The reference numerals are as follows:

[0015] 1. Base plate, 2. Clamping seat, 3. Screws, 4. Bolts, 5. Fiber metal plate, 6. Positioning plate, 7. Screws, 8. Sealing tape, 9. Cylindrical pin. DETAILED DESCRIPTION

[0016] The embodiments of the technical solution of the present application will be described in detail below in conjunction with the accompanying drawings. Unless otherwise specified, the technical terms or scientific terms used in the present application are generally understood by those skilled in the art to which the present invention belongs.

[0017] The gas turbine sealing belt welding method of this embodiment includes:

[0018] S1. Determine the thickness of the solder according to the shape of the sealing tape 8;

[0019] S2, assembling and fixing the sealing tape 8, the fiber metal plate 5 and the solder together accordingly;

[0020] S3, assembling the fixed sealing tape 8, fiber metal plate 5 and solder onto the tooling;

[0021] S4. Put the assembled tooling into a high-temperature vacuum brazing furnace, and vacuum braze the sealing belt 8 and the fiber metal plate 5 according to the process conditions.

[0022] This embodiment adopts reasonable brazing materials and brazing processes to produce the heavy-duty gas turbine sealing belt, which can not only improve the reliability and performance of the product, but also the innovation of materials and processes can extend the service life of the sealing belt, reduce the maintenance frequency, and ultimately improve the overall performance and economy of the heavy-duty gas turbine.

[0023] The above scheme is further described below with examples:

[0024] In step S1, the surfaces of the sealing tape and the base material need to be clean and free of oxides, and may need to be polished, cleaned or chemically treated to ensure that the brazing interface is clean and free of impurities. According to the shape of the sealing tape after the transition section of the heavy-duty gas turbine, hand-cut BNi82CrSiBFe (AMS4777) sheet brazing filler metal with a thickness of 0.05 mm, which can be slightly larger than the fiber metal.

[0025] In step S2, the heavy-duty gas turbine transition section rear sealing belt and the fiber metal plate and the brazing material are assembled together and fixed by resistance spot welding or argon arc welding. The argon arc welding adopts the self-fluxing method or the wire filling method. The welding parameters are as follows:

[0026] Welding materials Welding wire specifications Welding current Gas flow ERNiCr-3 Φ1.6 / Φ2.0 70-120A 9-15L

[0027] Add more brazing material at the edge of the weld to ensure that the brazing material overflows from the weld after brazing.

[0028] In step S3, a flow barrier is applied around the workpiece and on the brazing tooling to prevent the workpiece from adhering to the tooling after brazing. Then, the rear sealing belt of the transition section of the heavy-duty gas turbine after spot welding is assembled on the tooling.

[0029] In step S3, the tooling includes a base plate 1, a clamping seat 2 and a positioning plate 6;

[0030] The sealing belt comprises an arc segment, a first segment and a second segment, wherein the first segment and the second segment are arranged vertically.

[0031] The sealing belt is placed on the bottom plate 1, the second section of the sealing belt is arranged between the bottom plate 1 and the positioning plate 6 and clamped by the two, the solder is placed on the first section of the sealing belt, the fiber metal plate 5 is placed on the solder, the fiber metal plate 5 is tightened by the bolt 4 screwed on the clamping seat 2, and the bottom plate 1 and the clamping seat 2 are connected together. The clamping seat 2 and the bottom plate 1 are also provided with positioning holes and cylindrical pins 9 located in the positioning holes.

[0032] The bottom plate 1 and the positioning plate 6 are fixed by screws 7 that pass through the positioning plate 6 and are screwed onto the bottom plate 1 .

[0033] The base plate 1 and the clamping seat 2 are fixed by screws 3 which pass through the clamping seat 2 and are screwed onto the base plate 1 .

[0034] In step S4, the assembled tooling is placed in a high-temperature vacuum brazing furnace, and the sealing belt 8 and the fiber metal plate 5 are vacuum brazed according to the process conditions. The sealing belt assembled on the brazing tooling is placed on the bracket, kept in a horizontal welding position, and placed in a high-temperature vacuum brazing furnace together with the bracket.

[0035] The heat treatment curve and parameters of high temperature vacuum brazing process are as follows: ① heating rate 8±2℃ / min to 954±14℃; ② keeping at 954±14℃ for 10+5 / -0min; ③ heating rate 28±4℃ / min to 1052±14℃; ④ keeping at 1052±14℃ for 10+5 / -0min; ⑤ furnace cooling until the measuring temperature of all thermocouples is lower than 954±14℃; ⑥ argon cooling to 66±14℃ and then air cooling to room temperature.

[0036] After brazing is completed, check the brazing condition, grind the welding points to ensure smooth transition, and adjust the shape of the sealing belt after welding to meet product requirements.

[0037] The present invention has been disclosed as above with preferred implementation cases, but it is not intended to limit the present application. Any technician familiar with the profession can make slight changes or modifications to equivalent implementation cases with equivalent changes by using the above-disclosed structures and technical contents without departing from the scope of the technical solution of the present application, which still fall within the scope of the technical solution of the present application.

Claims

1. A gas turbine sealing belt welding method, characterized in that: The method comprises: S1. Determine the thickness of the solder according to the shape of the sealing tape (8); S2, assembling and fixing the sealing tape (8), the fiber metal plate (5) and the solder together accordingly; S3, assembling the fixed sealing tape (8), fiber metal plate (5) and solder onto the tooling; S4. Put the assembled tooling into a high-temperature vacuum brazing furnace, and vacuum braze the sealing belt (8) and the fiber metal plate (5) according to the process conditions.

2. The gas turbine sealing belt welding method according to claim 1, characterized in that: The brazing material in step S1 is BNi82CrSiBFe.

3. The gas turbine sealing belt welding method according to claim 1, characterized in that: The fixing method in step S2 is resistance spot welding or argon arc spot welding.

4. The gas turbine sealing belt welding method according to claim 3, characterized in that: The argon arc welding adopts a self-fluxing method or a wire-filling method.

5. The gas turbine sealing belt welding method according to claim 1, characterized in that: The brazing process parameters of step S4 are: heating rate 8±2℃ / min, heating to 954±14℃, keeping warm for 10-15min, then heating to 1052±14℃ at a heating rate of 28±4℃ / min, keeping warm for another 10-15min, cooling the brazing furnace to below 954±14℃, then cooling to 66±14℃ with argon gas, and then air cooling to room temperature.

6. The gas turbine sealing belt welding method according to claim 1, characterized in that: The solder in step S1 is in the form of a sheet with a thickness of 0.05 mm.

7. The gas turbine sealing belt welding method according to claim 1, characterized in that: In step S3, the tooling comprises a base plate (1), a clamping seat (2) and a positioning plate (6); The sealing belt comprises an arc segment, a first segment and a second segment, wherein the first segment and the second segment are arranged vertically. The sealing belt is placed on the bottom plate (1), the second section of the sealing belt is arranged between the bottom plate (1) and the positioning plate (6) and is clamped by the two, the first section of the sealing belt is placed with solder, the fiber metal plate (5) is placed on the solder, the fiber metal plate (5) is tightened by bolts (4) screwed on the clamping seat (2), and the bottom plate (1) and the clamping seat (2) are connected together.

8. The gas turbine sealing belt welding method according to claim 7, characterized in that: The bottom plate (1) and the positioning plate (6) are fixed by screws (7) that pass through the positioning plate (6) and are screwed onto the bottom plate (1).

9. The gas turbine sealing belt welding method according to claim 7, characterized in that: The base plate (1) and the clamping seat (2) are fixed by screws (3) passing through the clamping seat (2) and screwed onto the base plate (1).

10. The gas turbine sealing belt welding method according to any one of claims 1 to 9, characterized in that: After brazing is completed, check the brazing condition, grind the welding points to ensure smooth transition, and adjust the shape of the sealing belt after welding to meet product requirements.

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