A welding tool for heavy-duty gas turbine ring belt coating

Abstract

The present application relates to the technical field of engine ring processing equipment, in particular to a heavy-duty engine ring coating welding tool, which comprises a welding table and a cold gas nozzle; the welding table is in a groove shape, and the cold gas nozzle is arranged in the welding table, so that the cold gas nozzle can spray low-temperature gas flow to the ring placed on the welding table. The welding table is used for placing and positioning the ring. The cold gas nozzle can adopt a Rankine vortex tube, which is placed in the welding table with the cold end upward, so that it can be aligned with the inner wall of the ring placed above the welding table. When welding the outer wall of the ring, the cold end of the Rankine vortex tube blows air to the inner wall of the ring welding position to reduce the temperature, so that only the outer wall of the ring welding position generates high temperature, avoiding high-temperature breakdown of the ring, and effectively preventing deformation in welding.

Description

Technical Field

[0001] This invention relates to the technical field of gas turbine retaining ring processing equipment, and more specifically, to a welding fixture for a heavy-duty gas turbine retaining ring with a coating. Background Technology

[0002] The circular retaining ring of a gas turbine is a core stator component of heavy-duty gas turbines. Unlike the fan-shaped assembled retaining ring, it is integrally forged and machined without a central splicing surface. It serves to enclose the gas flow channel around the turbine blades, playing a crucial role in maintaining blade tip clearance, providing thermal insulation, and suppressing gas cross-flow. The retaining ring is mostly made of nickel-based high-temperature alloy and has a thin-walled annular structure. Several through-holes are formed along the circumference of the ring wall, penetrating the sidewalls. During production and assembly, auxiliary parts need to be placed on the outer wall of the retaining ring and around the through-holes, and then fixed to the outer wall of the retaining ring using argon arc welding.

[0003] Current processing methods generally employ conventional manual TIG welding or ordinary automated TIG welding equipment to weld the outer wall accessories of the retaining ring. TIG welding involves high arc temperatures and concentrated heat sources in the molten pool. However, the circular retaining ring is a thin-walled annular structure with weak radial stiffness and low local heat capacity. Welding heat is concentrated in a narrow area around the through-hole, making it highly susceptible to two typical defects: first, the arc heat penetrates the thin-walled substrate of the retaining ring, causing sidewall breakdown and hole collapse, directly rendering the retaining ring unusable; second, the large local temperature gradient during welding generates significant uneven thermal stress, leading to circumferential elliptical deformation and localized concave-convex deformation of the retaining ring. The retaining ring is a high-precision annular component; post-weld deformation will compromise the accuracy of the inner circular surface of the retaining ring, altering the blade tip clearance of the turbine blades. During unit operation, this will increase gas leakage and exacerbate the risk of blade rubbing, failing to meet the requirements for gas turbine assembly and long-term operation.

[0004] Currently, the industry's conventional methods for addressing such welding challenges mainly rely on optimizing welding process parameters, increasing preheating before welding, setting up simple external cooling fixtures, and dividing the welding sequence to disperse heat input. However, these measures can only alleviate the risk of defects to a certain extent and cannot fundamentally suppress heat accumulation in thin-walled areas. The presence of openings in the base material cross-section at through-hole locations leads to significant stress concentration effects, further amplifying the tendency for burn-through and deformation. The process window is narrow, welding quality is highly dependent on the welder's skill level, batch stability is poor, rework is difficult, and rework welding can introduce secondary thermal damage, impairing the high-temperature mechanical properties of the retaining ring base material.

[0005] Furthermore, most existing welding fixtures can only achieve simple workpiece positioning and clamping, lacking an integrated structure for uniform temperature support, localized directional temperature control, and dynamic thermal compensation on the inner wall of a full-circle thin-walled retaining ring. This makes it impossible to effectively conduct heat and provide rigid support to the inner side of the retaining ring during welding, hindering the simultaneous achievement of the two core objectives of preventing substrate penetration and controlling thermal deformation of the ring component. Therefore, there is an urgent need to develop a dedicated welding equipment suitable for welding the outer wall accessories of a full-circle thin-walled gas turbine retaining ring, solving the technical problems of easy penetration of the retaining ring sidewall and difficulty in controlling welding thermal deformation in existing argon arc welding processes. Summary of the Invention

[0006] The purpose of this invention is to provide a welding fixture for a heavy-duty gas turbine retaining ring with a coating, which can prevent the workpiece from being damaged by high temperature during welding.

[0007] The embodiments of the present invention are achieved through the following technical solutions: A welding fixture for coating a heavy-duty gas turbine retaining ring includes a welding table and a cold air nozzle; the welding table is trough-shaped, and the cold air nozzle is disposed inside it so that the cold air nozzle can spray a low-temperature gas flow onto the retaining ring placed on the welding table.

[0008] Furthermore, it also includes a support mechanism; the support mechanism includes a base plate and columns disposed on the floor; the welding table is disposed on the top of the columns.

[0009] Furthermore, it also includes a lifting mechanism; the lifting mechanism includes a jacking mechanism, a sleeve, a crossbar, and a lifting rod; the sleeve is fitted onto the outside of the column so that the sleeve can slide relative to the column; the crossbar is disposed on the sleeve and extends to both sides of the sleeve; both ends of the crossbar are fitted with the lifting rods in conjunction with the guard rings so that the two lifting rods can lift the guard rings to the welding table; the jacking mechanism is disposed below the crossbar so that the lifting mechanism can lift the crossbar up and down.

[0010] Furthermore, the lifting rod is a rotating roller.

[0011] Furthermore, it also includes a leaning frame; the leaning frame also includes a sleeve and a crossbar that cooperate with the column; the crossbar of the leaning frame is connected to the crossbar of the lifting mechanism through a support rod; both ends of the crossbar of the leaning frame are also equipped with rotating rollers that cooperate with the guard ring, so that the lower end of the guard ring is supported by the rotating roller of the lifting mechanism, and the upper end leans against the rotating roller of the leaning frame.

[0012] Furthermore, the outer diameter of the part of the rotating roller that contacts the retaining ring is smaller than that of other parts, so that the rotating roller forms a sunken step.

[0013] Furthermore, the welding table is equipped with a slide rail inside; the cold air nozzle is disposed on the slide rail.

[0014] Furthermore, the opening at the top of the welding station is provided with retaining edges on both sides so that the retaining ring is embedded between the two retaining edges.

[0015] Furthermore, the welding table is provided with an adjustment window on its side.

[0016] Furthermore, the base plate is also provided with operating steps.

[0017] The technical solutions of the embodiments of the present invention have at least the following advantages and beneficial effects: This tooling integrates a built-in Rank vortex tube cooling nozzle within the slotted welding station. Leveraging the cooling and heating characteristics of the vortex tube's compressed air, it enables directional and precise low-temperature airflow cooling of the inner wall of the retaining ring during argon arc welding of the outer wall. This effectively solves the problems of substrate breakdown and hole collapse caused by heat concentration and low heat capacity in the welding area of ​​thin-walled retaining rings under existing processes. Simultaneously, it effectively reduces the local temperature rise gradient and uneven thermal stress during welding, suppresses circumferential and local thermal deformation of the retaining ring, and precisely ensures the accuracy of the inner circular surface of the retaining ring, meeting the requirements of gas turbine assembly and operation.

[0018] This fixture employs a dedicated support structure with a base plate and vertical columns. The solid base plate increases the support contact area and lowers the center of gravity of the equipment. Together with the columns, the welding table is stably suspended at a height suitable for manual operation. This effectively eliminates the problem of fixture shaking and displacement during heavy-duty retaining ring operations, improves the overall stability of the equipment, and solves the drawbacks of traditional fixtures that lack dedicated support and result in limited welding operations and high difficulty due to the low placement of the retaining ring. It also optimizes the welding operation field of vision and ease of operation.

[0019] This fixture employs a lifting and supporting structure using rectangular columns, limiting sleeves, symmetrical horizontal lifting rods, and a cylinder lifting mechanism. The rectangular columns provide circumferential limiting for the sleeves, enabling precise vertical sliding. Combined with the symmetrical lifting rods on both sides, it forms a ring-like support. The cylinder extension and retraction mechanism allows for the automated lifting and precise docking of heavy-duty, large-size retaining rings with the welding table. This completely avoids the problems of laborious lifting, positioning deviation, and high safety risks associated with manual lifting of heavy-duty retaining rings. While reducing the intensity of manual labor, it ensures the reference accuracy of retaining ring welding and clamping.

[0020] This fixture, by setting the lifting rod as a rolling roller structure, combined with the lifting mechanism, can achieve the lifting and detachment of the retaining ring and its unobstructed circumferential rotation. It can quickly complete the switching of different welding points in the circumference without disassembling and re-clamping the retaining ring, effectively solving the problems of difficult rotation of workpieces after clamping and large positioning errors after multiple clamping in traditional fixtures. It greatly improves the work efficiency of multi-point continuous welding, while ensuring the positioning consistency and welding quality uniformity of each welding point.

[0021] This fixture, by adding a slanted support frame structure that is linked to the lifting mechanism for lifting, and relying on the upper and lower support of the double sets of rotating rollers of the slanted support frame and the lifting mechanism, can accurately adapt to the tilted placement posture of the flared-mouth-shaped protective ring, so that the shaped protective ring is evenly stressed and placed stably. It effectively solves the problems that a single bottom support cannot adapt to the shaped protective ring, the clamping tilt, and the easy occurrence of micro-displacement during the welding process. At the same time, the linkage structure simplifies the material loading and assembly process of the protective ring, reduces the need for continuous manual support, and greatly improves the safety of operation and the stability of clamping.

[0022] This fixture features a recessed, stepped, irregularly shaped structure that is thinner in the middle and thicker at both ends on the lifting rod and the inclined support rotating rod. By using stepped grooves to limit and constrain the upper and lower parts of the retaining ring, it can effectively restrict the lateral displacement and axial sliding of the retaining ring in the inclined state. This eliminates problems such as slippage and swaying during the operation of the retaining ring, which can lead to welding trajectory deviation, uneven heating, and aggravated deformation. It further improves the welding clamping accuracy of the retaining ring and ensures the batch consistency of the welding of accessories at each through hole position.

[0023] This fixture features an adjustable structure with sliding rails and cooling nozzles inside the welding station cavity. This allows for flexible adjustment of the cooling air jet position based on the different arrangements of welding points around the retaining ring. This ensures that the low-temperature airflow accurately corresponds to the inner wall of the retaining ring at each welding point, solving the shortcomings of traditional fixed nozzles that cannot adapt to multi-point welding and inadequate local cooling. This comprehensively improves the cooling effect and welding quality uniformity of all welding points around the retaining ring.

[0024] This fixture, with its symmetrical limiting baffles on both sides of the opening at the top of the welding table, features a slot-type positioning structure that enables rapid embedding, positioning, and fixation of the retaining ring. This effectively limits lateral and radial swaying during the welding process, ensuring precise alignment between the welding point of the retaining ring and the internal cooling nozzle. It eliminates the need for repeated workpiece position calibration, simplifies the clamping and positioning process, avoids temperature control misalignment and uneven heating caused by workpiece displacement, and significantly improves the overall stability of the welding process.

[0025] This fixture, by opening an adjustment window on the side of the welding table for manual operation, allows for convenient fine-tuning of the position and spray angle of the cooling nozzles without disassembling the welding table housing. This significantly improves the flexibility and convenience of temperature control structure adjustment, and can adapt to the precise temperature control requirements of different working conditions and different specifications of retaining rings, thus comprehensively avoiding the risks of burn-through and thermal deformation during welding of thin-walled retaining rings.

[0026] This tooling integrates a single high-level operating step structure on the base plate, adapting to the welding height requirements of the top point of the large-diameter retaining ring. It effectively solves the problems of poor visibility, limited operating posture, and unstable welding trajectory in conventional ground operations, optimizes the operator's operating posture and accuracy, reduces welding quality fluctuations caused by manual operation, and, together with various temperature control, support, and positioning structures of the tooling, comprehensively ensures the quality stability and batch reliability of welding of heavy-duty gas turbine retaining ring outer wall accessories. Attached Figure Description

[0027] Figure 1 A front view of the welding fixture for the coating of the retaining ring of a heavy-duty gas turbine.

[0028] Figure 2 for Figure 1 Enlarged view of point a in the middle.

[0029] Figure 3 A schematic diagram of the back of the welding fixture for the coating of the retaining ring of a heavy-duty gas turbine.

[0030] Figure 4 for Figure 3 Enlarged view of point b in the middle.

[0031] Figure 5 This is a schematic diagram showing the cold air nozzles installed inside the welding station.

[0032] Reference numerals: 1-Welding table, 2-Cold air nozzle, 3-Base plate, 4-Column, 5-Lifting mechanism, 6-Sleeve, 7-Horizontal bar, 8-Lifting rod, 9-Support rod, 10-Slide rail, 11-Side rail, 12-Adjustment window, 13-Operating step, 14-Guard ring, 15-Accessory, 16-Rotating roller. Detailed Implementation

[0033] like Figures 1-5As shown, this embodiment addresses the technical shortcomings of existing argon arc welding processes for the outer wall accessory 15 of the full-circle thin-walled gas turbine retaining ring 14. These shortcomings include the thin-walled substrate being easily broken down by the high temperature of the electric arc, heat accumulation around the through-hole causing thermal deformation, and the lack of a dedicated internal wall directional temperature control structure. A special tooling adapted for welding the full-circle retaining ring 14 is designed, with the core comprising a grooved welding table 1 and a built-in cooling nozzle 2. This fundamentally solves the problems of burn-through and deformation during welding of the thin-walled retaining ring 14. The welding table 1 adopts an integral grooved structure, serving as the core load-bearing and positioning base for the welding operation of the retaining ring 14. It can stably place the full-circle thin-walled retaining ring 14 to be welded, effectively limiting the overall displacement of the retaining ring 14 during the welding process and providing a reference support for the welding operation. The cooling nozzle 2 preferably uses a Rankine vortex tube structure and is built into the cavity of the welding table 1. The overall layout is concealed and does not occupy welding operation space. During installation, the cold end of the vortex tube is ensured to face upwards, precisely corresponding to the inner wall of the welding area of ​​the retaining ring 14 above the welding table 1. The Rank vortex tube does not require an external cooling medium and can achieve airflow separation by relying solely on compressed air. Its core working principle is that after high-pressure compressed air enters the vortex tube, it will rotate at high speed along the tube wall to form a vortex. During the vortex motion, the airflow is automatically split into a central low-temperature cold airflow and an outer high-temperature hot airflow. The high-temperature hot airflow is directly discharged to the outside, while the low-temperature cold airflow is continuously ejected from the cold end. When performing argon arc welding on the auxiliary parts around the through hole on the outer wall of the retaining ring 14, the welding arc is concentrated in a small area on the outer wall of the retaining ring 14, which generates extremely high local heat. Meanwhile, the cold end of the eddy current tube continuously sprays a directional low-temperature airflow onto the inner wall of the corresponding welding position of the retaining ring 14, which can achieve precise cooling of the inner side of the thin-walled substrate of the retaining ring 14. This creates a temperature-controlled welding environment with high-temperature welding on the outer wall and directional temperature control on the inner wall. Only the welding area on the outer wall of the retaining ring 14 forms a weld pool, which quickly dissipates the welding heat accumulated inside the thin-walled substrate. This completely avoids the side wall penetration and hole collapse caused by the high temperature of the arc penetrating the thin-walled substrate, and at the same time, it significantly reduces the local temperature rise gradient during welding, suppresses the generation of uneven thermal stress, effectively improves the defects of circumferential elliptical deformation and local concave-convex deformation of the retaining ring 14, and ensures the machining accuracy of the inner circular surface of the retaining ring 14.

[0034] This fixture is also equipped with a support mechanism, which serves as the load-bearing base structure for the entire fixture. This mechanism enables the welding table 1 to be suspended and stably fixed, adapting to the welding requirements of the large-sized heavy-duty retaining ring 14. The support mechanism mainly consists of a base plate 3 and columns 4 fixedly mounted on the base plate 3. The base plate 3 adopts a solid plate structure, increasing the contact area with the ground and effectively lowering the overall center of gravity of the fixture. This prevents the fixture from swaying or shifting during the placement and rotation of the heavy-duty retaining ring 14, ensuring the stability of the entire equipment. The columns 4 are vertically fixed to the upper surface of the base plate 3, providing a vertical support foundation for the welding table 1. This raises the welding table 1 to the optimal operating height for manual welding, placing the retaining ring 14 in a suitable working position. This completely solves the problems of traditional welding fixtures lacking a dedicated support structure, the retaining ring 14 being placed too low, and the inconvenience of welding operations. It significantly reduces the difficulty of manual argon arc welding and improves the convenience of welding operations and the operator's field of vision.

[0035] To accommodate the loading, unloading, and assembly requirements of the heavy-duty circular retaining ring 14, which has a diameter of approximately two meters and a relatively large weight, a dedicated lifting mechanism was added to the tooling. This mechanism enables automated lifting and docking of the retaining ring 14, avoiding the problems of laborious manual lifting, positioning deviation, and high safety risks. The lifting mechanism consists of a lifting mechanism 5, a sleeve 6, a crossbar 7, and two sets of lifting rods 8. The sleeve 6 is fitted onto the outside of the column 4 according to its external dimensions, and the two adopt a precision sliding fit structure. The column 4 is designed as a rectangular column structure, which can circumferentially limit the sleeve 6, allowing the sleeve 6 to slide only vertically along the column 4, preventing the sleeve 6 from rotating or shifting, and ensuring the stability of the lifting process. The crossbar 7 is fixed laterally to the side wall of the sleeve 6 and extends symmetrically to the left and right sides of the sleeve 6. At each end of the crossbar 7, a set of lifting rods 8 is respectively assembled to the annular contour structure of the protective ring 14. The two sets of lifting rods 8 are symmetrically arranged and can accurately fit the bottom contour of the circular protective ring 14 to form an encircling support structure, which stably lifts and limits the protective ring 14 to prevent it from shifting or slipping during the lifting process. The lifting mechanism 5 is fixedly installed between the crossbar 7 and the base plate 3. It uses a vertical cylinder as a power source. The bottom end of the cylinder is fixed to the base plate 3 and the top end is connected to the lower end face of the crossbar 7. The extension and retraction of the cylinder drives the crossbar 7 and the sleeve 6 to rise and fall vertically along the column 4, thereby driving the lifting rods 8 and the protective ring 14 lifted above to rise and fall as a whole. During operation, the lifting mechanism can be lowered to the ground position to conveniently place the heavy-duty retaining ring 14, and then the lifting mechanism 5 can be used to lift the retaining ring 14, automatically completing the precise docking of the retaining ring 14 with the welding table 1. No manual handling or lifting is required, which greatly reduces labor intensity and ensures the assembly and positioning accuracy of the retaining ring 14.

[0036] The lifting rod 8 specifically adopts a roller 16 structure, which enables the retaining ring 14 to rotate circumferentially without resistance, meeting the needs of continuous welding at multiple points. After the welding of a single point attachment 15 of the retaining ring 14 is completed, there is no need to disassemble and re-clamp the workpiece. The lifting rod 8 is slightly raised by the lifting mechanism 5 to lift the retaining ring 14 as a whole and remove it from the contact surface of the welding table 1, eliminating the friction limit of the welding table 1 on the retaining ring 14. At this time, relying on the rolling characteristics of the roller 16, the retaining ring 14 can be easily and manually driven to rotate smoothly and circumferentially around its own central axis, quickly and accurately switching the new point to be welded to the area above the cold air nozzle 2 and the welding operation position. This greatly simplifies the switching process of multi-station welding, avoids the problems of difficult workpiece rotation after clamping and fixing with traditional tooling, and large positioning errors after multiple clamping and fixing, effectively improving the welding operation efficiency, while ensuring the positioning consistency of each welding point.

[0037] To address the issue that the heavy-duty gas turbine retaining ring 14 has an overall funnel-shaped, irregular cylindrical structure, making it difficult to ensure placement stability with only bottom support, the tooling is further reinforced with a slanted support frame. This frame, together with the lifting mechanism, forms a two-way support system that accommodates the irregular shape of the retaining ring 14, ensuring stable clamping. The slanted support frame is equipped with a sleeve 6 that slides with the column 4 and a horizontally arranged crossbar 7. The sleeve 6 is also fitted onto the outside of the column 4, allowing its height to be adjusted according to operating conditions. The crossbar 7 of the slanted support frame and the crossbar 7 of the lifting mechanism are fixedly connected by a support rod 9, enabling synchronous lifting and positional linkage between the two, ensuring the integrity and stability of the overall support structure. The two ends of the crossbar 7 of the inclined support frame are also symmetrically equipped with rollers 16. During operation, the bottom of the guard ring 14 is supported on the upper end face of the rollers 16 of the lifting mechanism, and the upper side wall leans against the inner side of the rollers 16 of the inclined support frame. Relying on the cooperation and limiting of the upper and lower sets of rollers 16, it perfectly adapts to the inclined placement posture of the trumpet-shaped guard ring 14, so that the guard ring 14 is evenly stressed and placed stably, completely solving the problems of tilting, uneven stress, and micro-displacement during welding of irregular guard ring 14. In the initial loading and assembly stage of guard ring 14, guard ring 14 can be adjusted to a vertical state so that most of the weight is borne on the lifting rod 8. The operator only needs to provide a small auxiliary limiting force to avoid interference from the column 4. After the guard ring 14 is lifted into place, it can be stably leaned against the rollers 16 of the inclined support frame. Subsequent welding and point switching operations do not require continuous manual support, greatly reducing the intensity of manual operation and improving the safety and stability of operation.

[0038] Both the lifting rod 8 and the roller 16 on the inclined frame adopt a differentiated outer diameter structure design. The outer diameter of the middle section of the roller 16 that directly contacts the retaining ring 14 is smaller than that of the two ends, so that the contact area of ​​the roller 16 forms a concave sunken step structure. After the retaining ring 14 is clamped at an inclined position, the bottom annular contour of the retaining ring 14 is inserted into the sunken step of the roller 16 on the lifting rod 8, and the upper side wall is inserted into the sunken step of the roller 16 on the inclined frame. Through the limiting constraint of the step, the lateral displacement and axial sliding of the retaining ring 14 can be restricted at the same time, which completely solves the problem of slippage and wobbling of the retaining ring 14 when it is placed at an incline. It also eliminates the problems of welding trajectory deviation, uneven heating and aggravated deformation caused by the micro displacement of the workpiece during the welding process, further improving the clamping accuracy and stability of the retaining ring 14 during the welding process and ensuring the consistency of welding of the accessories 15 around each through hole.

[0039] The welding station 1 cavity is equipped with a slide rail 10 structure, and the cold air nozzle 2 is slidably installed above the slide rail 10, which can realize precise adjustment of the cold air spray position to adapt to the temperature control requirements of multiple welding points at different positions around the circumference of the retaining ring 14. Since multiple through holes are evenly distributed around the circumference of the retaining ring 14, and the welding points are arranged along the ring, there are slight deviations in position. The slide rail 10 can drive the cold air nozzle 2 to slide freely and adjust its horizontal position, so that the low temperature airflow spray center of the cold air nozzle 2 always accurately corresponds to the inner wall area of ​​the retaining ring 14 at each welding point. This ensures that each welding position can receive precise and corresponding directional cooling, avoiding the defects caused by the inability of traditional fixed nozzle structures to adapt to multi-point welding and insufficient local cooling, thus comprehensively improving the uniformity of welding quality at each point.

[0040] The welding station 1 has integrally formed retaining edges 11 on both sides of the top opening. The retaining edges 11 are symmetrically arranged on both sides to form a limiting groove that matches the outer contour of the retaining ring 14. When the retaining ring 14 is placed on the top of the welding station 1, it can be directly embedded into the groove between the two retaining edges 11. Through the rigid limiting effect of the retaining edges 11, the retaining ring 14 can be quickly positioned and fixed, effectively limiting the lateral displacement and radial sway of the retaining ring 14 during the welding process. This ensures that after the retaining ring 14 is clamped, the inner wall of each welding point is always precisely aligned with the internal cold air nozzle 2. There is no need to repeatedly calibrate the workpiece position, simplifying the welding positioning process, reducing the clamping and adjustment time, and avoiding temperature control misalignment and uneven welding heating caused by workpiece displacement, further improving the stability of the welding process.

[0041] The welding station 1 has an adjustment window 12 that runs through its side. The window size is adapted to the operating space of a human hand. The operator can directly reach into the cavity of the welding station 1 through the side adjustment window 12 to conveniently adjust the left and right position, spray angle and height of the cold air nozzle 2 on the slide rail 10. The nozzle position can be finely adjusted without disassembling the housing of the welding station 1, which greatly improves the convenience and flexibility of adjusting the position of the cold air nozzle 2. It can accurately adapt the temperature control position for different specifications of the retaining ring 14 and different welding conditions, further optimize the local temperature control effect of the thin-walled retaining ring 14, and comprehensively avoid the risk of welding burn-through and thermal deformation.

[0042] The tooling base plate 3 has an integrated operating step 13 structure on its outer side. The height of the operating step 13 is adapted to the welding requirements of the top of the large-diameter retaining ring 14 (two meters in diameter). Due to the large overall size and high erection height of the circular retaining ring 14, conventional ground-based standing operations are not suitable for welding operations at the top points of the retaining ring 14, resulting in poor operating visibility, difficulty in arm exertion, and unstable welding trajectory. The dedicated operating step 13 raises the operator's standing height, allowing the operator to stand stably on the step and perform argon arc welding operations directly facing the welding points on the top of the retaining ring 14. This optimizes the operating posture and operating visibility, improves welding operation accuracy, reduces welding quality fluctuations caused by human operation errors, and, together with the tooling's temperature control and support structure, comprehensively ensures the welding quality and batch stability of the outer wall accessory 15 of the heavy-duty gas turbine circular retaining ring 14.

Claims

1. A welding fixture for a heavy-duty gas turbine retaining ring with a coating, characterized in that: It includes a welding table and a cold air nozzle; the welding table is trough-shaped, and the cold air nozzle is arranged inside it so that the cold air nozzle can spray a low-temperature airflow onto a retaining ring placed on the welding table.

2. The welding fixture for the coating of the heavy-duty gas turbine retaining ring according to claim 1, characterized in that: It also includes a support mechanism; the support mechanism includes a base plate and a column disposed on the base plate; the welding table is disposed on the top of the column.

3. The welding fixture for the coating of the heavy-duty gas turbine retaining ring according to claim 2, characterized in that: It also includes a lifting mechanism; the lifting mechanism includes a jacking mechanism, a sleeve, a crossbar, and a lifting rod; the sleeve is fitted onto the outside of the column so that the sleeve can slide relative to the column; the crossbar is disposed on the sleeve and extends to both sides of the sleeve; both ends of the crossbar are equipped with the lifting rod in conjunction with the guard ring so that the two lifting rods can lift the guard ring to the welding table; the jacking mechanism is disposed below the crossbar so that the lifting mechanism can lift the crossbar up and down.

4. The welding fixture for the coating of the heavy-duty gas turbine retaining ring according to claim 3, characterized in that: The lifting rod is a rotating roller.

5. The welding fixture for the coating of the heavy-duty gas turbine retaining ring according to claim 4, characterized in that: It also includes a leaning frame; the leaning frame also includes a sleeve and a crossbar that fit with the column; the crossbar of the leaning frame is connected to the crossbar of the lifting mechanism through a support rod; the two ends of the crossbar of the leaning frame are also equipped with rotating rollers that fit with the guard ring, so that the lower end of the guard ring is supported by the rotating roller of the lifting mechanism, and the upper end leans against the rotating roller of the leaning frame.

6. The welding fixture for the coating of the heavy-duty gas turbine retaining ring according to claim 5, characterized in that: The outer diameter of the part of the rotating roller that contacts the retaining ring is smaller than that of other parts, so that the rotating roller forms a sunken step.

7. The welding fixture for the coating of the heavy-duty gas turbine retaining ring according to claim 6, characterized in that: The welding table is equipped with a slide rail inside; the cold air nozzle is located on the slide rail.

8. The welding fixture for the coating of the heavy-duty gas turbine retaining ring according to claim 7, characterized in that: The welding station has side flanges on both sides of the opening at the top, so that the retaining ring can be embedded between the two side flanges.

9. The welding fixture for the coating of the heavy-duty gas turbine retaining ring according to claim 8, characterized in that: An adjustment window is provided on the side of the welding table.

10. The welding fixture for the coating of the heavy-duty gas turbine retaining ring according to claim 9, characterized in that: The base plate is also equipped with operating steps.

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