A welding tooling for a turbine stator vane ring and its welding method

Abstract

The present invention discloses a welding tooling for a turbine stator vane ring and a welding method thereof. S1: Process the surface to be welded and the surrounding area of the stator vane; S2: Clamp the stator vane into the welding tooling; S3: Demagnetize the stator vane ring and the welding tooling; S4: Dip a non-woven fabric in acetone or alcohol and wipe the surface to be welded; S5: Place the stator vane ring and the welding tooling into a vacuum chamber and weld the stator vane ring with a small welding heat input; S6: Complete the welding of the stator vane ring with preset welding parameters and welding sequence; S7: After welding, maintain in the vacuum chamber environment for 10 min to 20 min, and then deflate and take out. The present invention uses the high-voltage and high-vacuum electron beam welding technology to complete the welding of the turbine stator vane ring with preset welding parameters, welding positions and sequence, and uses a special welding tooling for clamping, which can greatly reduce the deformation of the turbine stator vane ring caused by welding stress, making the connection between the stator vanes more reliable, firm and stable.

Description

Technical Field

[0001] The present invention belongs to the technical field of turbine stator blade ring welding, and particularly relates to a welding tooling for a turbine stator blade ring and a welding method thereof. Background Art

[0002] Turbocharging equipment is a forced intake system. They deliver air to the engine intake at a greater density than would be possible in a normal aspiration configuration, thus allowing more fuel to be burned and therefore increasing the horsepower of the engine without a significant increase in engine weight. The stator vane ring assembly is a common component in large turbocharging equipment in the aviation or other fields. The stator blade ring is composed of individual stator blades. The stator blade includes a blade root, a blade body, and a blade crown. The blade root and the blade crown are respectively welded or integrally formed at both ends of the blade body, and finally, the stator blade ring is manufactured in different ways. The stator blade ring structure has been widely used in many fields, such as in aviation and automotive engines.

[0003] Currently, there are many manufacturing methods for the stator blade ring:

[0004] 1. A type of axial flow compressor uses mechanical connection. The whole can be composed of a housing and a stator blade ring. The housing can be divided into an upper housing and a lower housing, and the stator blade ring can also be divided into a plurality of stator blade sectors in the circumferential direction. In the upper housing and the lower housing, there are formed blade ring grooves that are recessed from the inner side in the diameter direction toward the outer side in the diameter direction and extend in the circumferential direction. Each stator blade sector is assembled on any one of the blade ring grooves of the upper housing or the lower housing.

[0005] 2. Many aviation engine stator blades work in the form of a fan-shaped segment assembly. The fan-shaped segment assembly is formed by welding a plurality of single blades together. The specific operation method is to first spot-weld a filler metal sheet on the welding surfaces of each single blade, then use an assembly fixture to arrange and position each single blade, and then use a positioning welding method to connect each single blade into an integral assembly. The dimensions on the blade side of the stator blade ring cannot be machined after welding, and part deformation needs to be controlled during the welding process.

[0006] The existing brazing has problems such as low efficiency, poor quality, and being non-environmental; while the mechanical connection has problems such as unreliable, insecure, and unstable connection, and the processing and assembly procedures are complex, with high requirements for the machining accuracy of the stator blades. Summary of the Invention

[0007] The purpose of the present invention is to provide a welding tooling for a turbine stator blade ring and a welding method thereof to solve or improve the above problems in view of the above deficiencies in the prior art.

[0008] To achieve the above object, the technical solution adopted by the present invention is:

[0009] In a first aspect, the present invention provides a welding tooling for a turbine stator blade ring, including a chassis, a pressing block, a guiding disk, and an outer restraint; the chassis is respectively bolt-connected to the pressing block, the guiding disk, and the outer restraint;

[0010] The upper and lower surfaces of the outer restraint are both provided with first countersunk threaded holes, and the outer restraint is used to limit the outer ring of the stator blade ring;

[0011] The chassis is internally provided with a plurality of large sector holes evenly distributed, and a small stepped hole is provided between two adjacent large sector holes and is connected to the pressing block through the small stepped hole;

[0012] The chassis is provided with a small circular ring-shaped convex platform, and a plurality of second countersunk threaded holes are evenly distributed on the small circular ring-shaped convex platform; the guiding disk is provided with large stepped holes adapted to the second countersunk threaded holes; the guiding disk is provided with a plurality of guiding tracks for guiding the claws; a disk wire is embedded in the small circular ring-shaped convex platform, and a planar thread adapted to the claws is provided on the disk wire; the planar thread drives the claws to move along the guiding tracks to circumferentially clamp and release the stator blades;

[0013] The pressing block is provided with a large circular ring-shaped convex platform for positioning and pressing the stator blades; the pressing block is internally provided with a plurality of small sector holes evenly distributed, and a threaded hole is provided between two adjacent small sector holes, and the threaded hole is adapted to a bolt for connecting the pressing block to the chassis.

[0014] Further, the pressing block is circular ring-shaped and includes an upper pressing block and a lower pressing block; the upper pressing block and the lower pressing block are cooperatively connected by a second bolt and a pressing nut to press and position the stator blade ring in the vertical direction.

[0015] Further, the inner diameter of the large circular ring-shaped convex platform of the pressing block is the same as the outer diameter of the blade root of the stator blade, and the outer diameter of the large circular ring-shaped convex platform is the same as the inner diameter of the blade crown of the stator blade.

[0016] Further, a bearing is used to connect between the contact surfaces of the disk wire and the chassis, and a plurality of rolling elements are evenly distributed in the bearing; the diameter of the disk wire is the same as the inner diameter of the small circular ring-shaped convex platform of the chassis, and the disk wire and the small circular ring-shaped convex platform are connected by clearance fit.

[0017] Further, a plurality of sector-shaped baffles are provided between the claws and the stator blade ring, and at least two claws act on the sector-shaped baffles.

[0018] In a second aspect, the present invention provides a welding method for a welding tooling for a turbine stator blade ring, including the following steps:

[0019] S1. Grind and remove rust from the welding surface of the stator blade and the surrounding 20 mm area;

[0020] S2. Clamp the stationary blade into the welding fixture. When assembling the stationary blade, the assembly gap is less than 0.05 mm, and round the assembled stationary blade ring;

[0021] S3. Demagnetize the stationary blade ring and the welding fixture until the magnetic flux density is less than 1×10 -4 T;

[0022] S4. After the demagnetization treatment is completed, wipe the surface to be welded with non-woven fabric dipped in acetone or alcohol;

[0023] S5. Place the stationary blade ring and the welding fixture into the vacuum chamber, and weld the stationary blade ring with a small welding heat input, and complete the welding according to the preset welding sequence;

[0024] S6. After the stationary blade ring is completely cooled, complete the welding of the stationary blade ring with the preset welding parameters and welding sequence;

[0025] S7. After the welding is completed, keep it in the vacuum chamber environment for 10 min to 20 min, and then vent and take it out;

[0026] S8. Heat-treat the welded stationary blade ring and the welding fixture together. After the heat treatment is completed, disassemble the stationary blade ring and the circular fixture.

[0027] Further, the preset welding sequence in step S5 and step S6 is the first weld seam, the second weld seam, the third weld seam, the fourth weld seam and the fifth weld seam; and the welding track in step S6 coincides with the shallow weld seam formed in step S5.

[0028] Further, the welding parameters of the small welding heat input in step S5 are:

[0029] The working distance is 204 - 324 mm, the accelerating voltage is 60 - 140 kV, the focusing current is 510 - 2550 mA, the welding beam current is 16 - 36 mA, and the welding speed is 100 - 120 mm / min.

[0030] Further, the vacuum degree in the vacuum chamber in step S5 and step S6 needs to reach 6×10 -4 Pa;

[0031] In step S5 and step S6, after one weld seam is completed, disassemble the stationary blade ring and turn it over for clamping, that is, turn over the stationary blade ring and the pressing block, and then position and connect the pressing block and the bottom plate through the third bolt.

[0032] Further, in step S5 and step S6, the welding fixture is placed in the vacuum chamber and kept in a horizontal state, and the welding fixture is placed at the center of the rotatable welding platform.

[0033] The welding tooling and welding method for the turbine stator blade ring provided by the present invention have the following beneficial effects:

[0034] The present invention uses the high-pressure and high-vacuum electron beam welding technology to complete the welding of the turbine stator blade ring with preset welding parameters, welding positions and sequences, which can greatly reduce the deformation of the turbine stator blade ring caused by welding stress, making the connection between the stator blades more reliable, firm and stable.

[0035] At the same time, the present invention designs a circular fixture required for using this method, that is, the welding tooling. This fixture uses an upper clamping block and a lower clamping block to clamp the stator blade ring in the vertical direction. At the same time, a claw is used to push a sector baffle and an outer restraint to realize the radial clamping and positioning of the stator blade ring, and the restraint of the stator blade ring in the vertical direction is achieved during the welding process of each weld seam, so that the surface profile runout of the stator blade ring composed of the outer crowns of each stator blade and the flatness of the reference end face are greatly reduced, greatly improving the influence of welding deformation. Brief Description of the Drawings

[0036] Figure 1 It is a top view of the welding tooling for the turbine stator blade ring.

[0037] Figure 2 It is a sectional view of the welding tooling for the turbine stator blade ring.

[0038] Figure 3 It is an exploded view of the welding tooling for the turbine stator blade ring.

[0039] Figure 4 It is a structure diagram of the stator blade ring.

[0040] Figure 5 It is a schematic three-dimensional structure diagram of the circular fixture (welding tooling).

[0041] Figure 6 It is a schematic diagram of the electron beam welding position.

[0042] Wherein, 1, the first weld seam; 2, the second weld seam; 3, the third weld seam; 4, the fourth weld seam; 5, the fifth weld seam; 6, the stator blade; 601, the blade crown; 602, the blade body; 603, the blade root; 7, the outer restraint; 701, the first countersunk threaded hole; 8, the pressing block; 802, the small sector hole; 803, the large ring-shaped convex platform; 9, the pressing nut; 10, the first bolt; 11, the claw; 12, the guide disk; 1201, the large stepped hole; 1202, the guide track; 13, the wire coil; 14, the sector baffle; 15, the chassis; 1501, the second countersunk threaded hole; 1502, the small stepped hole; 1503, the through hole; 1505, the small ring-shaped convex platform; 16, the second bolt; 17, the third bolt; 18, the fourth bolt; 19, the rolling element. Detailed Description of the Invention

[0043] The specific embodiments of the present invention will be described below to facilitate those skilled in the art of this technology to understand the present invention. However, it should be clear that the present invention is not limited to the scope of the specific embodiments. For those of ordinary skill in the art of this technology, as long as various changes are within the spirit and scope of the present invention defined and determined by the appended claims, these changes are obvious, and all inventions and creations using the concept of the present invention are within the scope of protection.

[0044] Example 1, referring to Figures 1 to 6 , the welding tooling for the turbine stator vane ring of this solution. The welding tooling in this embodiment is a circular fixture, which controls the welding deformation of the stator vane ring while improving the weld quality, meeting the design dimension requirements, and also greatly shortening the production cycle, reducing the labor cost, and improving the production efficiency. It specifically includes a chassis 15, a pressing block 8, a guide plate 12, and an outer restraint 7; the chassis 15 is respectively connected to the pressing block 8, the guide plate 12, and the outer restraint 7 by bolts.

[0045] To prevent serious deformation of the stator vane ring during welding, an outer restraint 7 is provided in this embodiment. There are first countersunk threaded holes 701 on the upper and lower surfaces of the outer restraint 7, and correspondingly, the chassis 15 also has through holes 1503 of the same number, so as to connect the chassis 15 and the outer restraint 7 together by the fourth bolt 18, and the outer restraint 7 restricts the outer circle of the stator vane ring.

[0046] There are several uniformly distributed large sector holes in the chassis 15. There is a small stepped hole 1502 between two adjacent large sector holes, which is connected to the pressing block 8 through the small stepped hole 1502, and the connection between the pressing block 8 and the chassis 15 is realized through the cooperation of the third bolt 17 and the pressing nut 9.

[0047] There is a small circular ring-shaped boss 1505 on the chassis 15. There are multiple second countersunk threaded holes 1501 uniformly distributed on the small circular ring-shaped boss 1505. The small circular ring-shaped boss 1505 is connected to the guide plate 12. There is a large stepped hole 1201 on the guide plate 12 that is adapted to the second countersunk threaded holes 1501, and the large stepped hole 1201 is used to cooperate with the first bolt 10 to connect to the chassis 15.

[0048] There are several guide tracks 1202 for guiding the jaws 11 on the guide plate 12; a wire disk 13 is inlaid in the small circular ring-shaped boss 1505, and there is a planar thread on the wire disk 13 that cooperates with the jaws 11; when the wire disk 13 rotates, the jaws 11 are driven to move along the guide tracks 1202 through the planar thread, thereby realizing the circumferential clamping and relaxation of the stator vanes 6.

[0049] The pressing block 8 is provided with a large circular ring-shaped convex platform 803 for positioning and pressing the stationary blade 6; several uniformly distributed small fan-shaped holes 802 are provided inside the pressing block 8, and a threaded hole is provided between two adjacent small fan-shaped holes 802. The threaded hole is adapted to the third bolt 17 for connecting the pressing block 8 to the chassis 15.

[0050] As a further technical solution of the pressing block 8 in this embodiment, the pressing block 8 is circular ring-shaped and includes an upper pressing block 8 and a lower pressing block 8. The upper pressing block 8 and the lower pressing block 8 are cooperated with the second bolt 16 and the pressing nut 9 to press and position the stationary blade ring in the vertical direction.

[0051] The inner diameter of the large circular ring-shaped convex platform 803 of the pressing block 8 is the same as the outer diameter of the blade root 603 of the stationary blade 6, and the outer diameter of the large circular ring-shaped convex platform 803 is the same as the inner diameter of the blade crown 601 of the stationary blade 6.

[0052] Reference Figure 6 , the stationary blade 6 includes a blade crown 601, a blade body 602 and a blade root 603.

[0053] The contact surface between the wire coil 13 and the chassis 15 is connected in a bearing manner. Several uniformly distributed rolling elements 19 are provided inside the bearing. The friction between the wire coil 13 and the chassis 15 is reduced by the rolling elements 19, making it more labor-saving during the clamping process.

[0054] The diameter of the wire coil 13 is the same as the inner diameter of the small circular ring-shaped convex platform of the chassis 15, and the wire coil 13 is connected to the small circular ring-shaped convex platform 1505 by clearance fit.

[0055] During the radial pressing process of the clamping jaw 11 on the stationary blade ring, several fan-shaped baffles 14 are provided between the clamping jaw 11 and the stationary blade ring. Through the fan-shaped baffles 14, it can be ensured that the clamping force received by each stationary blade 6 in the stationary blade ring is uniform, and at least two clamping jaws 11 act on the fan-shaped baffles 14.

[0056] Embodiment 2, reference Figures 1 to 6 , the welding method of the welding tool for the turbine stationary blade ring in this embodiment. This method uses high-voltage and high-vacuum electron beam welding technology to weld the stationary blade ring with preset welding parameters, welding positions and sequences, and specifically includes the following steps:

[0057] Step S1: Grind and remove rust from the welding surface of the stationary blade 6 and the surrounding 20 mm area, and then use a non-woven fabric to dip acetone or wipe with alcohol on the welding surface and the surrounding area to ensure that there are no oil stains, rust, moisture, oxides and other harmful substances on the welding surface and the surrounding 20 mm area;

[0058] Step S2: Clamp the stationary blade 6 into a circular fixture (welding tool). When assembling the stationary blade 6, the assembly gap is less than 0.05 mm, and the assembled stationary blade ring is roundness-corrected;

[0059] Step S3: Demagnetize the stator blade ring and the welding fixture until the magnetic flux density is less than 1×10 -4 T;

[0060] Step S4: After the demagnetization treatment is completed, use non-woven fabric dipped in acetone or alcohol to wipe the surface to be welded;

[0061] Step S5: Place the stator blade ring and the welding fixture into the vacuum chamber, and weld the stator blade ring with a relatively small welding heat input, and complete the welding according to the preset welding sequence to fix each stator blade ring to prevent deformation due to excessive welding heat input during the subsequent welding process;

[0062] Step S6: After the stator blade ring is completely cooled, complete the welding of the stator blade ring with the preset welding parameters and welding sequence;

[0063] Step S7: After the welding is completed, maintain it in the vacuum chamber environment for 10 min to 20 min, and then vent and take it out;

[0064] Step S8: Heat-treat the welded stator blade ring and the welding fixture together. After the heat treatment is completed, disassemble the stator blade ring and the circular fixture.

[0065] Specifically, in Step S5 and Step S6 of this embodiment, the welding sequence is as Figure 5 shown, and weld the first weld seam 1, the second weld seam 2, the third weld seam 3, the fourth weld seam 4 and the fifth weld seam 5 in sequence.

[0066] In Step S5, the welding parameters for the relatively small welding heat input are: the working distance is 204 - 324 mm, the accelerating voltage is 60 - 140 kV, the focusing current is 510 - 2550 mA, the welding beam current is 16 - 36 mA, and the welding speed is 100 - 120 mm / min.

[0067] In Step S6, the welding parameters are: the working distance is 204 - 324 mm, the accelerating voltage is 60 - 140 kV, the focusing current is 510 - 2550 mA, the welding beam current is 80 - 180 mA, and the welding speed is 500 - 600 mm / min.

[0068] In Step S5 and Step S6:

[0069] The vacuum degree in the vacuum chamber needs to reach 6×10 -4 Pa.

[0070] After welding a weld seam, it is necessary to disassemble and turn over the stator blade ring for clamping. During each reinstallation of the stator blade ring, there is no need to disassemble the pressing block 8. Only the third bolt 17 needs to be disassembled, then the stator blade ring and the pressing block 8 are turned over, and then the pressing block 8 and the bottom plate are positioned and connected through the third bolt 17.

[0071] After each welding, it must be completely cooled in the vacuum chamber before it can be taken out and the stator blade ring can be reinstalled to prevent the weld seam from oxidizing due to overheating.

[0072] During the entire electron beam welding process, the circular fixture remains horizontally placed in the vacuum chamber.

[0073] The circular fixture is placed at the center of a rotatable welding platform, and the rotation speed of the welding platform can be controlled, that is, the welding speed can be controlled during the welding process.

[0074] A fixing device is provided between the welding platform and the circular fixture. The fixing device can be an existing one, so that the circular fixture remains in the same position each time it is placed and does not move during the welding process.

[0075] In step S6, the welding trajectory during welding should be highly coincident with the shallow weld seam formed in step S5.

[0076] Example 3. For the stator blade 6 in this example, 12Cr12Mo martensitic heat-resistant steel is used. The specific electron beam welding steps are as follows:

[0077] Step T1: Grind and remove rust from the weld surface to be welded and the surrounding 20 mm area of the test plate. Then use a non-woven fabric dipped in acetone or alcohol to wipe the weld surface to be welded and the surrounding area to ensure that there are no oil stains, rust, moisture, oxides and other harmful substances in the weld surface to be welded and the surrounding 20 mm area;

[0078] Step T2: Clamp the test plate into the circular fixture. When assembling the test plate, the assembly gap is less than 0.05 mm;

[0079] Step T3: Demagnetize the test plate and the circular fixture together until the magnetic flux density is less than 1×10 -4 T;

[0080] Step T4: After the test plate and the fixture are demagnetized, use a non-woven fabric dipped in acetone or alcohol to wipe the weld surface to be welded;

[0081] Steps T5 and T6: Place the test plate and the fixture in the vacuum chamber and keep them horizontally placed. Bring the vacuum degree in the vacuum chamber to 6×10 -4 Pa, and weld the test plate;

[0082] The welding parameters are:

[0083] The working distance is 204 mm, the accelerating voltage is 80 kV, the focusing current is 2000 mA, the welding beam current is 95 mA, and the welding speed is 200 mm / min;

[0084] Step T7: After welding, keep it in the high-vacuum environment of the vacuum chamber for 15 minutes, then vent and take it out;

[0085] After completing the above steps, through X-ray inspection, no welding cracks were found on the welding test plate.

[0086] The present invention uses high-voltage and high-vacuum electron beam welding technology to complete the welding of the turbine stator vane ring with preset welding parameters, welding positions and sequences, greatly reducing the influence of welding deformation, and making the connection between the stator vanes 6 more reliable, firm and stable.

[0087] The present invention designs a circular fixture using this method. The upper pressing block 8 and the lower pressing block 8 are used to restrict the stator vane ring in the vertical direction, and the jaws 11 and the outer restraint 7 are used to restrict the stator vane ring radially, greatly reducing the deformation of the stator vane ring during welding.

[0088] The detachable pressing block 8 of the present invention enables the stator vane ring to be restricted to a certain extent every time it is turned over, reducing the influence of turning over on the welding process of the stator vane ring.

[0089] Although the specific embodiments of the invention have been described in detail in conjunction with the accompanying drawings, it should not be construed as a limitation on the protection scope of this patent. Within the scope described in the claims, various modifications and deformations that can be made by those skilled in the art without creative labor still fall within the protection scope of this patent.

Claims

1. A welding tooling for a turbine stator blade ring, characterized in that: It includes a chassis, a pressing block, a guiding disk and an outer restraint; the chassis is respectively connected to the pressing block, the guiding disk and the outer restraint by bolts; One - sunk - head threaded holes are provided on both the upper and lower surfaces of the outer restraint, and the outer restraint is used to restrict the outer ring of the stator blade ring; A number of evenly - distributed large sector - shaped holes are provided in the chassis, a small stepped hole is provided between two adjacent large sector - shaped holes, and it is connected to the pressing block through the small stepped hole; A small circular - ring - shaped boss is provided on the chassis, and a number of second - sunk - head threaded holes are evenly distributed on the small circular - ring - shaped boss; a large stepped hole adapted to the second - sunk - head threaded hole is provided on the guiding disk; a number of guiding tracks for guiding the claws are provided on the guiding disk; a disk spring is inlaid in the small circular - ring - shaped boss, and a flat thread for cooperating with the claws is provided on the disk spring; the flat thread drives the claws to move along the guiding tracks to circumferentially clamp and relax the stator blades; A large circular - ring - shaped boss for positioning and pressing the stator blades is provided on the pressing block; a number of evenly - distributed small sector - shaped holes are provided in the pressing block, a threaded hole is provided between two adjacent small sector - shaped holes, and the threaded hole is adapted to the bolt for connecting the pressing block to the chassis; The pressing block is circular - ring - shaped and includes an upper pressing block and a lower pressing block; the upper pressing block and the lower pressing block are pressed and positioned in the vertical direction of the stator blade ring through the cooperation of a second bolt and a pressing nut; The inner diameter of the large circular - ring - shaped boss of the pressing block is the same as the outer diameter of the blade root of the stator blade, and the outer diameter of the large circular - ring - shaped boss is the same as the inner diameter of the blade crown of the stator blade; A bearing is used to connect the contact surface between the disk spring and the chassis, and a number of evenly - distributed rolling elements are provided in the bearing; the diameter of the disk spring is the same as the inner diameter of the small circular - ring - shaped boss of the chassis, and the disk spring and the small circular - ring - shaped boss are connected by clearance fit; A number of sector - shaped baffles are provided between the claws and the stator blade ring, and at least two of the claws act on the sector - shaped baffles.

2. A welding method using the welding tooling for the turbine stator blade ring according to claim 1, characterized in that, It includes the following steps: S1. Grind and remove rust from the welding surface of the stator blade and the surrounding 20 - mm area; S2. Clamp the stator blade into the welding fixture. When assembling the stator blade, the assembly gap is less than 0.05 mm, and the assembled stator blade ring is roundness - corrected; S3. Demagnetize the stator vane ring and the welding tooling until the magnetic flux density is less than 1×10 -4 T; S4. After completing the demagnetization treatment, use non - woven fabric to dip acetone or alcohol to wipe the welding surface; S5. Put the stator blade ring and the welding fixture into the vacuum chamber, and perform shallow - pass welding on the stator blade ring with a small welding heat input, and complete the welding according to the preset welding sequence; S6. After the stator blade ring is completely cooled, complete the welding of the stator blade ring with the preset welding parameters and welding sequence; S7. After welding, keep it in the vacuum chamber environment for 10 min - 20 min, then let the air out and take it out; S8. Heat - treat the welded stator blade ring and the welding fixture together. After completing the heat treatment, disassemble the stator blade ring and the circular fixture.

3. The welding method of the welding tooling for the turbine stator vane ring according to claim 2, characterized in that, The preset welding sequence in step S5 and step S6 is the first weld seam, the second weld seam, the third weld seam, the fourth weld seam and the fifth weld seam; and the welding track in step S6 coincides with the shallow weld seam formed in step S5.

4. The welding method of the welding tooling for the turbine stator blade ring according to claim 2, characterized in that, The welding parameters of the small welding heat input in step S5 are: The working distance is 204~324 mm, the accelerating voltage is 60~140 kV, the focusing current is 510~2550 mA, the welding beam current is 16~36 mA, and the welding speed is 100~120 mm / min.

5. The welding method of the welding tooling for the turbine stator blade ring according to claim 3, characterized in that, The degree of vacuum in the vacuum chamber in steps S5 and S6 needs to reach 6×10 -4 Pa; In steps S5 and S6, after completing a weld seam, the stationary blade ring is disassembled and flipped for clamping, that is, the stationary blade ring and the pressing block are flipped, and then the pressing block and the bottom plate are positioned and connected by the third bolt.

6. The welding method of the welding tooling for the turbine stator blade ring according to claim 3, characterized in that, In the said steps S5 and S6, the welding fixture is placed in the vacuum chamber and kept in a horizontal placement state, and the welding fixture is placed at the center of the rotatable welding platform.

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