A method for repairing a convex rib damage of a ship sealing frame by additive manufacturing

Abstract

The application discloses a kind of convex rib damage additive repair methods of warship sealing frame, belong to laser additive remanufacturing technical field.The convex rib damage additive repair method of the application is divided into four parts of pretreatment, repair forming, post-processing, inspection, and repair forming is divided into straight edge laser cladding, circular arc angle pulse argon arc surfacing, and pulse argon arc surfacing is interval surfacing in partition, the plane of convex rib circular arc angle is divided into six groups of areas, first group area is carried out pulse argon arc surfacing according to the order of outer side, inner side and top surface of convex rib circular arc angle, then the second group area is carried out surfacing, and so on, until the outer side, inner side and top surface of convex rib circular arc angle are completely surfaced, and ensure that complete lap joint is realized between each area, to form corrosion-resistant layer;Interval surfacing in partition can minimize heat input to convex rib.The application can realize in-situ repair while ensuring that the substrate temperature is not higher than 100 DEG C.

Description

Technical Field

[0001] This invention belongs to the field of laser additive remanufacturing technology, specifically relating to an additive repair method for damage to protruding edges of ship sealing frames. Background Technology

[0002] With the development, production, and commissioning of various types of naval shipborne weapons and equipment, which are subjected to harsh marine environments such as high temperature, high humidity, and high salt spray for extended periods, structural and component wear, corrosion, rust, and fatigue failure frequently occur. This leads to malfunctions and other quality issues during normal operation, severely impacting equipment performance and troop training and combat capabilities. However, some maintenance projects face challenges such as difficulty in disassembling damaged parts, high added value, limited working space, and poor accessibility, posing significant risks and technical challenges to efficient equipment repair.

[0003] Laser additive remanufacturing (LAR) is a 3D printing-based technology that uses a laser as a heat source to melt and print materials layer by layer, repairing damaged parts through cladding. Compared to traditional subtractive manufacturing, it offers numerous advantages, including material savings, high forming efficiency, and environmental friendliness. Domestic and international scholars have conducted in-depth research on LAR, which is widely applied in shipbuilding, aerospace, oil extraction, mining, rail transportation, and biomedicine. However, there is a lack of prior engineering experience to draw upon for repairing and maintaining damaged naval equipment using LAR; furthermore, on-site repair is challenging, and the forming materials and processes require testing, verification, and further exploration to ensure the quality of equipment repair and performance restoration.

[0004] Chinese invention patent application number 201611153504.2 discloses a composite repair method for thin-walled parts based on pulsed laser and continuous laser additive manufacturing, including the following steps: (1) cleaning the surface of the damaged thin-walled structure; (2) measuring the dimensions of the area to be repaired in the damaged thin-walled structure; (3) confirming the material of the area to be repaired according to drawings or chemical analysis; (4) formulating a repair process; (5) pulsed laser repair; (6) continuous laser repair; (7) machining and quality inspection. However, laser welding has low efficiency and takes a long time, which cannot meet the needs of limited-time operations.

[0005] Chinese invention patent application number 202111580551.6 discloses a process method for automatic tungsten inert gas (TIG) welding of the corrosion-resistant layer of a flange sealing groove. The original method involved rotating the workpiece to complete the automatic TIG welding of the flange sealing groove corrosion-resistant layer; instead, the welding is performed by rotating the welding torch driven by a welding device. In this process, the flange sealing groove on the pipeline is an unused part and has no connection with other components. Continuous TIG welding is used for corrosion protection, so there is no need to consider the problem of high continuous TIG welding temperatures causing adverse effects on adjacent components. Summary of the Invention

[0006] The outer side of the ship's sealing frame is sealed and fixed to the mounting hole. Each ship's sealing frame is pressed and sealed by a hatch cover. When using laser cladding additive repair, due to space limitations, the laser cannot reach the arc corner of the ship's sealing frame. Furthermore, the high temperature of continuous argon arc welding can easily cause deformation of the ship's sealing frame, resulting in the failure of the seal between the ship's sealing frame and the mounting hole. Therefore, the base temperature should not exceed 100 degrees Celsius during additive repair. In addition, the high temperature of continuous argon arc welding also affects the properties of the ship's sealing frame material. Therefore, this invention provides an additive repair method for ship sealing frame convex edge damage where the base temperature should not exceed 100 degrees Celsius during additive repair.

[0007] The object of this invention is achieved in the following manner:

[0008] A method for additive repair of convex edge damage to a ship's sealing frame comprises four parts: pretreatment, repair forming, post-treatment, and inspection. The repair forming includes straight-edge laser cladding and pulsed argon arc welding of the sealing frame's rounded corners. The pulsed argon arc welding is a partitioned interval welding process. This partitioned interval welding involves dividing the area to be pulsed argon arc welded into grids, with each grid representing a partition for pulsed argon arc welding. The first group of grids with unconnected perimeters is selected as the first group of pulsed argon arc welding partitions, and so on, until all grids are selected. Then, pulsed argon arc welding is performed on the first group of pulsed argon arc welding partitions, and so on, until all grids are welded.

[0009] The partitioned welding process involves dividing each plane of the convex ridge's rounded corner into six evenly distributed groups: Group 1, Group 2, Group 3, Group 4, Group 5, and Group 6. The top surface of the convex ridge's rounded corner is divided into two or three rows. Partitioned pulsed argon arc welding is performed. Manually, the first group of areas is welded in the order of the outer surface, inner surface, and top surface of the convex ridge's rounded corner. Then, the second group of areas is welded in the same order, and so on, until the outer surface, inner surface, and top surface of the convex ridge's rounded corner are all welded. This ensures complete overlap between the areas, forming a corrosion-resistant layer. When the last area of ​​the first group is welded, the first area of ​​the first group has already cooled down. When welding the second group, heat accumulation on the substrate will not occur, preventing localized deformation. The partitioned welding process minimizes heat input to the convex ridge.

[0010] For straight-edge laser cladding, the robot performs the work along the length of the convex edge. Excluding the rounded corner, the cladding length is 740mm. From the interface between the rounded corner and the straight edge of the convex edge to the middle of the straight edge, the cladding thickness gradually decreases, forming a corrosion-resistant layer that is higher at both ends and lower in the middle. The cladding thickness x at the interface between the rounded corner and the straight edge of the convex edge can be obtained from the following formula:

[0011]

[0012] Where x is the cladding thickness at the interface between the arc corner and the straight edge of the convex ridge; H is the weld thickness at the middle position of the arc corner of the convex ridge; h is the cladding thickness at the middle position of the straight edge of the convex ridge; R is the radius of the arc at the middle position of the straight edge of the convex ridge; and L is the distance from the middle position of the straight edge of the convex ridge to the interface between the arc corner and the straight edge of the convex ridge.

[0013] The preprocessing (I):

[0014] This includes fitter's grinding, portable milling machine machining of reference surfaces, local pulsed argon arc welding, and local fitter's grinding;

[0015] 1) Fitter grinding

[0016] Before repair, the oxide film, oil stains and corrosion pits on the surface of the sealing frame and the convex edge of the sealing frame must be carefully cleaned. For the oxide film, use sandpaper and wire brush (wheel) to polish it. For the oil stains, use solvents such as alcohol and acetone to clean it. For the corrosion pits, use a rust removal hammer and steel to remove rust and polish the deeper rust pits. The maximum damage in the height direction of the deep corrosion pit is 0.5mm, and the maximum damage in the thickness direction is 3mm.

[0017] 2) Portable milling machine machining reference surface

[0018] Remove the four positioning bolts of the sealing frame, fix the four legs of the portable milling machine to the four positioning holes of the sealing frame with four positioning bolts, adjust the parallelism between the base of the portable milling machine and the protrusion to within 0.2mm, position and set the tool in a rust-free area, and machine the inner and outer sides and top surface of the protrusion. Machining 1.0mm on each side of the outer and inner sides of the protrusion, and machining the inner radius of the arc corners R70 to R71mm and the outer radius of R78 to 77mm to provide a reference surface for repair and shaping;

[0019] 3) Perform localized pulsed argon arc welding on the deep corrosion pits.

[0020] Before operation, check whether the welding machine is running normally and select metal wire XAB-MHEA-02;

[0021] Set the process parameters as follows: welding current 130-150A, welding voltage 20-27V, welding speed 5.0-8.0mm / s, gas flow rate 10-15L / min;

[0022] Use a WS-300S welding machine to perform local pulsed argon arc welding on the deep corrosion pits that still exist after machining. The welding depth should be about 0.5mm higher than the machined surface in step 2.

[0023] 4) Localized fitter grinding: Perform fitter grinding on the weld overlay area of ​​localized deep corrosion pits to form a consistent reference on the entire convex surface;

[0024] The repair shaping (II) also includes:

[0025] The on-site repair process is based on laser cladding and pulsed argon arc welding to form a corrosion-resistant layer on the part substrate, with a certain machining allowance. First, the convex edges and straight edges are repaired in sections by laser cladding, and then the rounded corners of the sealing frame are repaired in sections by pulsed argon arc welding.

[0026] Laser cladding repair: Laser cladding repair is performed on the straight edges of the convex ridges of the sealing ring. The specific steps are as follows:

[0027] 1) Clean the oxides and oil stains from the surface to be clad before cladding;

[0028] 2) Pre-operation checks, including whether the laser, robot, and powder feeder are operating normally, checking the air supply and pipeline tightness, and preparing metal powder material XAB-MHEA-02.

[0029] 3) During the repair and forming process, the argon gas storage tank is opened, and a synchronous protection method is used to provide an argon gas protective environment for the cladding layer to prevent oxidation of the cladding material;

[0030] 4) Set the process parameters: laser power 1450W, spot diameter 2.5mm, repair speed 700mm / min, overlap rate 50%, powder feed 28g / min, protective airflow 15L / min, and air pressure 0.5Mpa.

[0031] 5) Determine the path program and develop the robot path control program based on the partitioned scanning forming strategy; perform scanning on the outer side, inner side and top of the convex edge from bottom to top respectively, and use the robot cladding head to calibrate the red light to verify the trajectory.

[0032] 6) Execute the program to complete the repair and shaping of the protruding edge;

[0033] The outer, inner, and top surfaces of the protruding ridge are sequentially clad. Considering the relatively long size of the ridge and its small height and width, the repair process is carried out in segments along the length direction, dividing the outer, inner, and top surfaces of the ridge into 10 segments each. After the first segment is clad, the fourth segment is clad after a two-segment interval. After the fourth segment is clad, the seventh segment is clad after a two-segment interval. After the tenth segment is clad, the substrate temperature of the first segment has cooled down, and then the second segment is clad. Then, the fifth segment is clad after two more segments, and so on, until the outer, inner, and top surfaces of the protruding ridge are completely clad, ensuring complete overlap between each segment to form a corrosion-resistant layer. This segmented laser cladding method ensures, on the one hand, that the substrate temperature does not exceed 100 degrees Celsius throughout the cladding process, effectively preventing substrate deformation and / or changes in properties due to excessively high temperatures; on the other hand, it reduces maintenance time, avoiding maintenance interruptions due to excessively high substrate temperatures, thus reducing maintenance efficiency and minimizing waiting time for the substrate to cool down.

[0034] The robot performs the construction along the length of the convex edge. Excluding the rounded corner, the cladding length is 740mm. From the interface between the rounded corner and the straight edge of the convex edge to the middle of the straight edge, the cladding thickness gradually decreases, forming a corrosion-resistant layer that is high on both sides and low in the middle. The cladding thickness x at the interface between the rounded corner and the straight edge of the convex edge can be obtained from the following formula:

[0035]

[0036] Where x is the cladding thickness at the interface between the arc corner and the straight edge of the convex ridge; H is the weld thickness at the middle position of the arc corner of the convex ridge; h is the cladding thickness at the middle position of the straight edge of the convex ridge; R is the radius of the arc at the middle position of the straight edge of the convex ridge; and L is the distance from the middle position of the straight edge of the convex ridge to the interface between the arc corner and the straight edge of the convex ridge.

[0037] The cladding thickness at the interface between the rounded corner and the straight edge of the convex ridge is 1.9 mm; the cladding thickness at the middle of the straight edge of the convex ridge is 1.5 mm; the corrosion-resistant layer at the middle of the rounded corner of the convex ridge has the largest thickness, which is 2.0 mm; the corrosion-resistant layer at the interface between the rounded corner and the straight edge of the convex ridge is 1.9 mm, and it is ensured that it completely overlaps with the laser cladding area.

[0038] A corrosion-resistant layer is formed on the convex edge of the arc corner of the sealing ring by pulsed argon arc welding in sections:

[0039] Pulse welding technology has the characteristics of short arc discharge time and small discharge range. In order to minimize the heat input to the protruding edge, the argon arc pulse welding is performed on each surface of the rounded corner of the protruding edge by partitioned interval welding.

[0040] 1) Clean the oxides and oil stains from the surface to be clad before welding;

[0041] 2) Before operation, check whether the welding machine is running normally and select metal wire XAB-MHEA-02;

[0042] 3) Set the process parameters: welding current 130-150A, welding voltage 20-27V, welding speed 5.0-8.0mm / s, gas flow rate 10-15L / min;

[0043] 4) Manually operate the WS-300S welding machine to perform zoned and intermittent pulsed argon arc welding on the rounded corners of protruding edges:

[0044] Zoned intermittent welding: The planes of the convex ridge arc corner are divided into six evenly distributed groups: Group 1, Group 2, Group 3, Group 4, Group 5, and Group 6. The top surface of the convex ridge arc corner is divided into two or three rows. Zoned intermittent pulsed TIG welding is performed. Manually, the first group of areas is pulsed TIG welded in the order of the outer side, inner side, and top surface of the convex ridge arc corner. Then, the second group of areas is pulsed TIG welded in the same order, and so on, until the outer side, inner side, and top surface of the convex ridge arc corner are all welded. It is ensured that the areas are fully overlapped to form a corrosion-resistant layer. When the last area of ​​the first group of areas is welded, the first area of ​​the first group of areas has cooled down. When welding the second group of areas, heat accumulation on the substrate will not occur, causing local deformation. The intermittent welding can minimize the heat input to the convex ridge.

[0045] When performing zoned pulsed TIG welding on each surface of the convex ridge arc corner, the welding thickness decreases sequentially from the middle of the convex ridge arc corner to the position where it meets the straight edge of the convex ridge. That is, the corrosion-resistant layer at the middle of the convex ridge arc corner is higher than the corrosion-resistant layer at the interface between the arc corner and the straight edge of the convex ridge. The corrosion-resistant layer at the middle of the convex ridge arc corner is the thickest, at 2.0 mm. The corrosion-resistant layer at the interface between the arc corner and the straight edge of the convex ridge is 1.9 mm, and it is ensured that there is a complete overlap with the laser cladding area.

[0046] Overall, the thickness of the corrosion-resistant layer decreases sequentially from the middle of the rounded corner of the convex ridge to the middle of the straight edge of the convex ridge. The thickness of the corrosion-resistant layer is the largest at the middle of the rounded corner of the convex ridge, which is 2.0 mm, while the thickness of the corrosion-resistant layer is the smallest at the middle of the straight edge of the convex ridge, which is 1.5 mm. By increasing the thickness of the repair layer at the rounded corner of the convex ridge of the sealing frame, the corrosion resistance of the rounded corner of the convex ridge of the sealing frame is improved, the service life of the sealing frame is extended, and the maintenance frequency is reduced.

[0047] The post-processing (III) includes portable milling and bench polishing processes:

[0048] A portable milling machine is used to mill the outer, inner, and top surfaces of the raised ribs after laser cladding and pulse welding. This ensures the corrosion-resistant layer at the midpoint of the raised rib's arc corner is 1.5mm thick, and the corrosion-resistant layer at the midpoint of the raised rib's straight edge is 1.0mm thick. The corrosion-resistant layer on the sealing ring's raised rib forms a smooth slope from the midpoint of the arc corner towards the midpoint of the straight edge. From the midpoint of the arc corner towards the midpoint of the straight edge, it forms a frustum shape. The outer and inner surfaces of the raised rib are machined to ensure a rib width of 8.0±0.2mm, a rib height within the range of 10.5 to 10.0 ±0.2mm, and an inner radius (R) of 69.5mm to 69.6mm and an outer radius (R) of 78.5mm to 78.6mm for the sealing frame's arc corners.

[0049] Grind corners and other localized areas that cannot be reached by a portable milling machine, as well as tool marks, and polish the entire convex edge to make it flat and smooth.

[0050] The inspection (IV) involves dimensional and quality inspection of the repaired parts to ensure they meet technical requirements; the repaired sealing frame ridges are effectively restored in terms of size and watertightness through laser repair.

[0051] Beneficial effects: This invention uses a partitioned interval argon arc welding method. The protruding ridge is welded using partitioned interval pulse argon arc welding. Although the temperature of the protruding ridge welding area is very high, the partitioned welding area is only 4mm long, the wire specification is 0.6-1.0mm, and the width of the partitioned welding area is also about 4mm. That is, the partition area is small, and the surrounding area is a metal material that is easy to conduct heat. This ensures that the base temperature generally does not exceed 100 degrees Celsius, effectively avoiding changes in the properties of the ship's sealing frame material, and also effectively avoiding the ship's sealing frame from heat deformation. Attached Figure Description

[0052] Figure 1 Schematic diagram of a ship's sealing frame.

[0053] Figure 2 Top view of the ship's sealing frame.

[0054] Figure 3 A schematic diagram illustrating the overall repair process for the damaged sealing frame protrusion.

[0055] Figure 4 Schematic diagram of laser repair process.

[0056] Figure 5 A schematic diagram of the process implementation for laser repair of various equipment.

[0057] Figure 6 A photograph of the damaged area at the rounded corner of the protruding edge of the ship's sealing frame.

[0058] Figure 7 Schematic diagram of laser cladding of the straight edge of the ship's sealing frame with segmented intervals.

[0059] Figure 8 Schematic diagram of inter-area welding of the protruding ridges and rounded corners of the ship's sealing frame.

[0060] Figure 9 Schematic diagram of the corrosion-resistant layer on the protruding ridges of a ship's sealing frame.

[0061] Figure 10 Schematic diagram of the cross-section of the ribbed repair layer structure.

[0062] Figure 11 A photograph of a ship's sealing frame damaged by laser repair.

[0063] Among them, 1 to 6 are six groups of areas evenly distributed on the rounded corner of the convex edge of the ship's sealing frame; 100 is the positioning hole; 200 is the convex edge of the ship's sealing frame; 210 is the straight edge of the convex edge; 211 is the outer surface of the straight edge of the convex edge; 212 is the inner surface of the straight edge of the convex edge; 213 is the top surface of the straight edge of the convex edge; 214 is the middle position of the straight edge of the convex edge; 220 is the rounded corner of the convex edge; 221 is the outer surface of the rounded corner of the convex edge; 222 is the inner surface of the rounded corner of the convex edge; 223 is the top surface of the rounded corner of the convex edge; 224 is the middle position of the rounded corner of the convex edge; 230 is the interface position between the rounded corner of the convex edge and the straight edge of the convex edge; 240 is the localized corrosion pit on the convex edge; 250 is the corrosion-resistant layer of the convex edge. Detailed Implementation

[0064] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this invention, not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention. Therefore, the following detailed description of the embodiments of this invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention.

[0065] In this embodiment, the sealing frame is mainly made of Q345 steel and 925 alloy steel. Due to long-term seawater corrosion, pitting, spalling, and other volumetric damage have occurred, resulting in a decrease in the watertightness of the hatch cover. The damage is mainly concentrated at the protruding ribs of the sealing frame, with a maximum damage of 0.5 mm in the height direction and a maximum damage of 3 mm in the thickness direction.

[0066] Repair process design

[0067] (1) Selection of repair technology

[0068] This application adopts an overall repair process that primarily uses laser cladding technology and secondarily uses pulse welding technology.

[0069] The sealing frame consists of four rounded corners and four straight edges. The convex design has a thickness of 8.0 mm and a height of 10.0 mm. It is sensitive to heat input deformation during the cladding process, and heat input must be strictly controlled during on-site repair operations.

[0070] Based on the structure of the sealing frame and the on-site construction conditions, laser processing is not feasible at the four rounded corners due to interference. Therefore, a comprehensive repair solution is adopted, consisting of intermittent segmented straight-edge laser cladding and intermittent pulsed argon arc welding of the rounded corners of the sealing frame. Figure 1 As shown. The straight-edge laser cladding length is 740mm, including the inner side, outer layer and top surface of the protrusion, to minimize the heat input to the protrusion, and segmented interval laser cladding is used.

[0071] (2) Laser cladding technology

[0072] Utilizing the strong focusing capability of high-energy laser beams, a tiny molten pool is instantaneously formed on the substrate of the part, melting the synchronously fed metal powder and forming a corrosion-resistant coating with good metallurgical bonding to the substrate. This offers the following advantages:

[0073] a. Minimal thermal impact on the substrate. During laser processing, only the surface of the substrate material undergoes micro-melting, with a micro-melted layer of 0.05-0.1 mm. The heat-affected zone of the substrate is extremely small, typically 0.1-0.2 mm. The heat-affected zone of laser cladding is one-tenth that of argon arc welding;

[0074] b. Minimal thermal deformation of the repaired part. The substrate temperature rises low during laser processing, resulting in virtually no thermal deformation after laser processing;

[0075] c. The repaired area has good microstructure. Neither the cladding layer nor the substrate has coarse casting structure. The cladding layer and its interface have a dense structure with fine crystal powder and no defects such as pores, inclusions, or cracks.

[0076] d. Laser repair technology has good controllability and is easy to automate and intelligently control.

[0077] (3) Pulsed argon arc welding process technology

[0078] Pulsed argon arc welding technology, characterized by short arc discharge time and small discharge range, serves as an effective supplement to laser cladding in this application. Besides repairing areas inaccessible to laser cladding due to positional interference, pulsed argon arc welding also performs preliminary shaping of localized deep corrosion pits. It has the following characteristics:

[0079] a. It has good arc-starting performance and good adaptability of welding parameters to the workpiece being welded;

[0080] b. Heat input can be kept to a minimum;

[0081] c. Excellent resistance to porosity in the weld;

[0082] d. 25% higher efficiency than ordinary welding

[0083] The use of zoned, intermittent pulsed argon arc welding ensures that the base temperature generally does not exceed 100 degrees Celsius, effectively preventing changes in the properties of the ship's sealing frame material and also effectively preventing the convex edges of the ship's sealing frame from deforming due to heat.

[0084] (4) Design of the repair layer structure

[0085] To ensure the corrosion resistance of the repaired area, this application establishes a "fully enclosed" repair layer structure, such as... Figure 10As shown, a repair layer with a thickness of 1.0mm-1.5mm is formed on the original Q345 and 925 steel substrate. A 1.0mm repair layer is formed at the center of the straight edge of the protruding ridge, and a 1.5mm repair layer is formed at the center of the rounded corner of the protruding ridge. Figure 9 As shown, the repair layer has high strength and strong corrosion resistance, and forms a good metallurgical bond with the substrate, providing effective protection for the protrusions during service.

[0086] Selection of repair materials

[0087] The repair material selected in this application is a marine corrosion-resistant multi-component high-entropy alloy material independently developed by the National Defense Key Laboratory of Equipment Remanufacturing Technology, and is produced by Henan Xinganbang Electromechanical Equipment Manufacturing Co., Ltd.

[0088] The main components of the filament (model: XAB-MHEA-02W) and powder (model: XAB-MHEA-02P) are shown in Table 1 (mass fraction wt%):

[0089] Table 1. Main components of marine corrosion resistant multi-component high-entropy alloy materials

[0090]

[0091] The performance characteristics of the repair materials are shown in Table 2:

[0092] Table 2 Comparison of the performance of repair materials and conventional materials

[0093]

[0094] As can be seen from the comparison data in Table 2, the overall performance of the repair material is significantly better than that of the corrugated base material Q345 steel, its corrosion resistance (corrosion rate) and strength are better than those of 925 steel, and its corrosion resistance is better than that of 316L stainless steel.

[0095] This high-entropy alloy material exhibits excellent resistance to seawater corrosion after laser cladding and has been applied in the surface corrosion protection of hydraulic cylinder propellers in various types of marine engineering equipment.

[0096] Repair equipment

[0097] The equipment used for on-site repair in this application mainly includes: laser cladding equipment, pulse welding machine, and portable milling machine (application number 202110852774.7).

[0098] (1) Laser cladding equipment

[0099] The laser cladding equipment is a mobile robot, which facilitates on-site maintenance. Performance parameters are shown in Table 3.

[0100] Table 3 Main Equipment Components of Laser Cladding Machine

[0101]

[0102] (2) Pulse welding machine

[0103] The pulse welding equipment selected is the WS-300S welding machine. Main performance parameters:

[0104] Table 4 Main performance parameters of pulse welding machine

[0105] Serial Number project parameter 1 power supply voltage 380V 2 Power factor 0.93 3 Output current adjustment range 10-300 4 load continuity 60％

[0106] (3) Portable milling machine (application number 202110852774.7)

[0107] A portable milling machine was custom-developed to address the structural characteristics and processing requirements of the sealing frame, for on-site laser repair and post-processing on ships. The portable milling machine facilitates the milling of difficult-to-disassemble components on large equipment.

[0108] The performance characteristics are as follows:

[0109] a. Specialized equipment developed for on-site repair and processing on ships;

[0110] b. Not limited by workpiece size;

[0111] c. Retain the accuracy of floor-mounted machining centers;

[0112] d. Easy to move, basically not limited by location;

[0113] e. Machining accuracy ≤ 0.2mm.

[0114] Repair process

[0115] This process flow is divided into four parts: pretreatment (Ⅰ), repair and shaping (Ⅱ), post-treatment (Ⅲ), and inspection (Ⅳ). The overall repair implementation plan is as follows: Figure 3 As shown:

[0116] (I) Pretreatment:

[0117] This includes fitter's grinding, portable milling machine machining of reference surfaces, local pulsed argon arc welding, and local fitter's grinding;

[0118] 1) Fitter grinding: to remove oxide and rust layers;

[0119] 2) Portable milling machine machining reference surface: Machining the inner and outer sides and top surface of the protrusion to provide a reference surface for repair and shaping;

[0120] 3) Localized pulse welding: Welding is performed on deep, localized corrosion pits that still exist after machining;

[0121] 4) Localized fitter grinding: The weld overlay area with localized corrosion pits is ground by fitter grinding to form a consistent reference on the entire convex surface.

[0122] (II) Repair and shaping:

[0123] The on-site repair process involves forming a corrosion-resistant layer 250 on the part substrate using laser cladding and pulsed argon arc welding, with a certain machining allowance. First, the straight edges of the protruding ridges 210 are repaired in segments using laser cladding, and then the rounded corners 220 of the sealing frame are repaired in segments using pulsed argon arc welding.

[0124] (III) Post-processing

[0125] This includes portable milling and fitter polishing processes to restore the dimensions, precision, and surface quality of parts.

[0126] (IV) Test:

[0127] The repaired parts are subjected to dimensional and quality inspections to ensure they meet technical requirements.

[0128] Detailed process instructions

[0129] 5.1 Process 1: Fitter Grinding

[0130] 1) Before repair, the oxide film, oil stains and corrosion pits on the surface of the sealing frame and the 200mm protrusion of the sealing frame must be carefully cleaned. For the oxide film, use sandpaper and wire brush (wheel) in combination for polishing. For the oil stains, use solvents such as alcohol and acetone for cleaning.

[0131] 2) Use a rust-removing hammer and steel needle to remove rust from the inside of deeper rust pits 240 to ensure that there are no visible rust marks in areas that cannot be machined in step 2 of process 5.2.

[0132] 5.2 Process 2: Machining the reference surface with a portable milling machine

[0133] The inner and outer sides and top surface of the protruding rib are machined to provide a reference surface for repair and shaping.

[0134] 1) Remove the four positioning bolts of the sealing frame, fix the four legs of the portable milling machine to the four positioning holes 100 of the sealing frame with the four positioning bolts, and adjust the parallelism between the base of the portable milling machine and the protrusion 200 to within 0.2mm.

[0135] 2) Position the tool on a rust-free area, and machine the inner and outer sides and top surface of the convex edge. Machin the outer and inner sides of the convex edge by 1.0mm on each side, and machine the inner arc corners to R70 to R71mm and the outer arc corners to R78 to R77mm to provide a reference surface for repair and shaping. The surface roughness after machining should not be lower than Ra12.5, and there should be no rust visible to the naked eye.

[0136] 5.3 Process 3: Localized pulsed argon arc welding

[0137] Local pulsed argon arc welding was performed on the corrosion pit 240.

[0138] 1) Before operation, check whether the welding machine is running normally and select metal wire XAB-MHEA-02;

[0139] 2) Set the process parameters: welding current 130-150A, welding voltage 20-27V, welding speed 5.0-8.0mm / s, gas flow rate 10-15L / min;

[0140] 3) Use a WS-300S welding machine to perform local pulsed argon arc welding on the deep corrosion pits that still exist after machining. The welding depth should be about 0.5mm higher than the machining surface of step 2 in 5.2.

[0141] 5.4 Process 4: Partial fitter polishing

[0142] The surface is manually polished to remove the excess weld material from step 3 of process 5.3, making it basically consistent with the surface processed in step 2 of process 5.2.

[0143] 5.5 Process 5: Repair and Shaping

[0144] This process includes two sub-processes: process 5.5.1 laser cladding and process 5.5.2 pulse welding. Process 5.5.1 laser cladding is performed first, followed by process 5.5.2 pulse welding.

[0145] Process 5.5.1: Laser cladding: Perform segmented laser cladding on the straight edge 210 of the sealing ring's convex ridge.

[0146] 1) Before laser cladding, carefully clean the oxides and oil stains on the surface to be clad. Oxides are generally removed by sandpaper, wire brush (wheel), grinding wheel, etc.

[0147] 2) Pre-operation checks include checking whether the laser, robot, and powder feeder are operating normally, checking the air supply and pipeline tightness, and preparing metal powder material XAB-MHEA-02. The laser cladding equipment is a mobile robot type, moving with tracks and located to the side and rear of the workpiece to be repaired.

[0148] 3) During the repair and forming process, the argon gas storage tank is opened, and a synchronous protection method is adopted to provide an argon gas protection environment for the cladding layer to prevent oxidation of the cladding material.

[0149] 4) Setting laser cladding process parameters

[0150] Table 5 Laser Cladding Repair Process Parameters

[0151]

[0152] 5) Determine the path program and, based on the partitioned scanning forming strategy, develop the robot path control program. Perform scanning from the bottom up on the outer side, inner side, and top of the protrusion, and verify the trajectory using the robot's cladding head calibration red light.

[0153] 6) Execute the program to complete the repair and shaping of the protruding ridge. Perform sequential cladding processing on the outer surface 211, inner surface 212, and top surface 213 of the straight edge of the protruding ridge. Considering the relatively long size of the protruding ridge and its small height and width, the repair process is carried out in segments along the length direction, dividing each of the outer surface 211, inner surface 212, and top surface 213 of the straight edge of the protruding ridge into 10 segments. Figure 7 As shown, after the first segment is clad, the fourth segment is clad after a two-segment interval. After the fourth segment is clad, the seventh segment is clad after a two-segment interval. After the tenth segment is clad, the substrate temperature of the first segment has cooled down. Then the second segment is clad, and the fifth segment is clad after a two-segment interval, and so on, until the outer surface 211, inner surface 212, and top surface 213 of the protruding ridge are all clad, ensuring complete overlap between each segment to form a corrosion-resistant layer 250. This segmented laser cladding method ensures that the substrate temperature does not exceed 100 degrees Celsius throughout the cladding process, effectively preventing excessive substrate temperature from causing deformation and / or changes in properties. It also reduces maintenance time, avoiding maintenance interruptions due to excessively high substrate temperature, thus reducing maintenance efficiency and minimizing waiting time for the substrate to cool down.

[0154] The robot performs the cladding along the length of the convex edge, with a cladding length of 740mm (excluding the rounded corner). From the interface position 230 between the rounded corner and the straight edge of the convex edge to the middle position 214 of the straight edge of the convex edge, the cladding thickness gradually decreases, forming a corrosion-resistant layer that is high on both sides and low in the middle. The cladding thickness x at the interface position 230 between the rounded corner and the straight edge of the convex edge can be obtained from the following formula:

[0155]

[0156] Where x is the cladding thickness at the interface 230 between the arc corner and the straight edge of the convex ridge; H is the weld thickness at the middle position 224 of the arc corner of the convex ridge; h is the cladding thickness at the middle position 214 of the straight edge of the convex ridge; R is the radius of the arc at the middle position 224 of the straight edge of the convex ridge; and L is the distance from the middle position 214 of the straight edge of the convex ridge to the interface 230 between the arc corner and the straight edge of the convex ridge.

[0157] like Figure 9As shown, the cladding thickness at the interface between the rounded corner and the straight edge of the convex ridge (230) is 1.9 mm; the cladding thickness at the middle position (214) of the straight edge of the convex ridge is 1.5 mm. The corrosion-resistant layer thickness is the largest at the middle position (214) of the rounded corner of the convex ridge, which is 2.0 mm; the corrosion-resistant layer at the interface between the rounded corner and the straight edge of the convex ridge (230) is 1.9 mm, ensuring complete overlap with the laser cladding area.

[0158] Procedure 5.5.2: Pulsed TIG welding: Perform segmented, intermittent pulsed TIG welding on the 220° arc angle of the sealing ring protrusion.

[0159] 1) Before welding, carefully clean the oxides and oil stains on the surface to be welded. Oxides are generally removed by sandpaper, wire brush (wheel), grinding wheel, etc.

[0160] 2) Before operation, check whether the welding machine is running normally and select metal wire XAB-MHEA-02;

[0161] 3) Setting pulse welding process parameters

[0162] Table 6 Pulse welding parameters

[0163]

[0164] 4) In the areas that cannot be reached by cladding in process 5.5.1, complete the welding formation of each surface of the protrusion, with the welding thickness set to 1.9-2.0mm, and ensure complete overlap with the laser cladding area in process 5.5.1;

[0165] Manually operate the WS-300S welding machine to perform zoned and intermittent pulse argon arc welding on the convex edge with a 220° arc angle.

[0166] Partitioned surfacing involves dividing the area to be surfacing by a grid, with each grid representing a separate surfacing zone. The first group of grids, which are not connected to the surrounding area, is selected as the first surfacing zone. Then, the second group of grids, which are also not connected to the surrounding area, is selected as the second surfacing zone, and so on, until all grids are filled. Then, surfacing is performed on the first surfacing zone, and then on the second surfacing zone, and so on, until all grids are filled.

[0167] like Figure 8As shown, the planes of the convex ridge arc corner are divided into six uniformly distributed groups: Group 1, Group 2, Group 3, Group 4, Group 5, and Group 6. The top surface of the convex ridge arc corner is divided into two or three rows. Pulsed argon arc welding is performed at intervals. Manually, the first group of areas 1 is welded in the order of the outer surface 221, inner surface 222, and top surface 223 of the convex ridge arc corner. Then, the second group of areas 2 is welded in the same order, and so on, until all three surfaces are welded, ensuring complete overlap between the areas to form a corrosion-resistant layer 250. When the last area of ​​the first group of areas 1 is welded, the first area of ​​the first group of areas 1 has already cooled. When welding the second group of areas 2, heat accumulation on the substrate will not occur, preventing local deformation. The intervals between each weld operation minimize the heat input to the convex ridge.

[0168] When performing zoned, intermittent pulsed TIG welding on the surfaces of the convex ridge's rounded corner, the weld thickness decreases sequentially from the middle position 224 of the rounded corner to the position 230 where it intersects with the straight edge of the convex ridge. Specifically, the corrosion-resistant layer at the middle position 224 is thicker than the corrosion-resistant layer at the interface 230. The corrosion-resistant layer thickness is greatest at the middle position 224, at 2.0 mm; the corrosion-resistant layer at the interface 230 is 1.9 mm, ensuring complete overlap with the laser cladding area.

[0169] Overall, the thickness of the corrosion-resistant layer 250 decreases sequentially from the middle position 224 of the rounded corner of the convex ridge to the middle position 214 of the straight edge of the convex ridge. The thickness of the corrosion-resistant layer 250 is the largest at the middle position 224 of the rounded corner of the convex ridge, at 2.0 mm; and the thickness is the smallest at the middle position 214 of the straight edge of the convex ridge, at 1.5 mm. By increasing the thickness of the repair layer at the rounded corner of the convex ridge of the sealing frame, the corrosion resistance of the rounded corner of the convex ridge of the sealing frame is improved, the service life of the sealing frame is extended, and the maintenance frequency is reduced.

[0170] 5.6 Process 6: Portable Milling Machine Machining

[0171] The forming surface of step 5.5 is milled.

[0172] Due to the workpiece structure, the sealing frame is prone to vibration during machining, resulting in poor surface roughness and even localized chipping. Therefore, increasing the rotation speed and reducing the depth of cut should be adopted during on-site repair and machining.

[0173] The processing parameters are shown in the table below:

[0174] Table 7 Machining parameters for portable milling machines

[0175] Rotational speed (s / min) Feed rate (mm / min) Tool diameter (ф) Depth of cut (mm) 1000-3000 500 10 0.1-0.5

[0176] Process the protrusions according to the drawings to the dimensional range. Process the inner side according to the lower dimension and the outer side according to the upper dimension to ensure that the workpiece is within the tolerance and to ensure the thickness of the cladding layer.

[0177] A portable milling machine mills the outer surface 211, inner surface 212, and top surface 213 of the straight edge of the protruding ridge, and the outer surface 221, inner surface 222, and top surface 223 of the rounded corner of the protruding ridge, which have been laser cladding and pulse welding completed. This ensures that the corrosion-resistant layer 250 at the midpoint 224 of the rounded corner of the protruding ridge is 1.5 mm thick, and the corrosion-resistant layer 250 at the midpoint 214 of the straight edge of the protruding ridge is 1.0 mm thick. The corrosion-resistant layer 250 on the protruding ridge of the sealing ring forms a smooth slope from the midpoint 224 of the rounded corner of the protruding ridge to the midpoint 214 of the straight edge of the protruding ridge. From the midpoint 224 of the rounded corner of the protruding ridge to the midpoint 214 of the straight edge of the protruding ridge, it forms a frustum shape. Machining the outer and inner sides of the protruding ridge ensures that the width of the protruding ridge is 8.0±0.2mm, the height of the protruding ridge is within the range of 10.5 to 10.0 ±0.2mm, and the inner radius of the sealing frame arc corner is within the range of 69.5mm to 69.6mm and the outer radius is within the range of 78.5mm to 78.6mm.

[0178] 5.7 Process 7: Fitter grinding and polishing

[0179] 1) Grinding corners and other localized areas that cannot be reached by a machining center;

[0180] 2) Grinding away tool marks and other imperfections after machining processes 5 and 6;

[0181] 3) Polish the entire convex edge until it is flat and smooth.

[0182] 5.8 Process 8: Inspection

[0183] The repaired parts underwent dimensional and quality inspections to ensure they met technical requirements. The repaired sealing frame's raised ridges achieved the following effect: Figure 11 As shown, laser repair effectively restored the size and watertightness of the protruding edge.

[0184] Compared with existing technologies, this invention can improve the corrosion resistance of the rounded corners of the sealing frame's protrusions, and extend the service life of the sealing frame and reduce the frequency of maintenance by increasing the thickness of the repair layer at the rounded corners of the sealing frame's protrusions.

[0185] To ensure the corrosion resistance of the repaired area, this solution adopts a "fully enclosed" repair layer structure, which means that the repair layer is formed on the original steel substrate. The repair layer has high strength and strong corrosion resistance, and forms a good metallurgical bond with the substrate, which can effectively protect the protruding edges during service.

[0186] Compared with traditional ship equipment repair methods, this invention proposes a process based on laser cladding technology that enables efficient and precise shaping and in-situ repair of existing damaged substrates. This method can effectively solve problems such as difficulty in disassembling damaged parts, poor accessibility for repair, and limited operating space in ship repair.

[0187] The laser repair method proposed in this invention, when combined with other methods, can effectively improve the repair efficiency and quality of traditional repair projects, while reducing repair costs and labor intensity.

[0188] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several changes and improvements without departing from the overall concept of the present invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. An additive repair method for damage to the protruding edge of a ship's sealing frame, comprising four parts: pretreatment (Ⅰ), repair forming (Ⅱ), posttreatment (Ⅲ), and inspection (Ⅳ). The repair forming is divided into straight-edge laser cladding and pulsed argon arc welding of the rounded corner of the sealing frame. The pulsed argon arc welding is a partitioned interval welding. The partitioned interval welding is as follows: the planes of the rounded corner of the protruding edge are divided into six uniformly dispersed regions: the first region (1), the second region (2), the third region (3), the fourth region (4), the fifth region (5), and the sixth region (6). The top surface of the rounded corner of the protruding edge is divided into two or three rows. Partitioned interval pulsed argon arc welding is performed. The manual operation first performs pulsed argon arc welding on the first region (1) in the order of the outer side (221), the inner side (222), and the top surface (223) of the rounded corner of the protruding edge. Then, the second region (2) is performed pulsed argon arc welding in the same order. Until the outer side (221), inner side (222), and top surface (223) of the convex ridge arc corner are all welded, and ensure that the regions are fully overlapped to form a corrosion-resistant layer (250); when the last region of the first group of regions (1) is welded, the first region of the first group of regions (1) has cooled down. When welding the second group of regions (2), heat will not accumulate on the substrate, causing local deformation; each welding is spaced apart, which can minimize the heat input to the convex ridge; the straight edge laser cladding is carried out by the robot along the length of the convex ridge. Except for the arc corner, the cladding length is 740mm. From the arc corner and the straight edge interface position (230) to the middle position of the straight edge (214), the cladding thickness gradually decreases, forming a corrosion-resistant layer (250) that is high on both sides and low in the middle. The cladding thickness x at the arc corner and the straight edge interface position can be obtained by the following formula: in, x is the cladding thickness at the interface position (230) between the arc corner and the straight edge of the convex ridge; H is the cladding thickness at the middle position (224) of the arc corner of the convex ridge; h is the cladding thickness at the middle position (214) of the straight edge of the convex ridge; R is the radius of the arc at the middle position (224) of the arc corner of the convex ridge; L is the distance from the middle position (214) of the straight edge of the convex ridge to the interface position (230) between the arc corner and the straight edge of the convex ridge.

2. The additive repair method for damaged protruding edges of ship sealing frames as described in claim 1, characterized in that: The preprocessing (I): This includes fitter's grinding, portable milling machine machining of reference surfaces, local pulsed argon arc welding, and local fitter's grinding; 1) Fitter grinding Before repair, the oxide film, oil stains and corrosion pits on the surface of the sealing frame and the convex edge (200) of the sealing frame must be carefully cleaned. For the oxide film, sandpaper and wire brush (wheel) are used for polishing. For the oil stains, alcohol and acetone are used for cleaning. For the corrosion pits, a rust removal hammer and steel are used to remove rust and polish the deep rust pits. The maximum damage in the height direction of the deep corrosion pit is 0.5mm, and the maximum damage in the thickness direction is 3mm. 2) Portable milling machine machining reference surface Remove the four positioning bolts of the sealing frame, fix the four legs of the portable milling machine to the four positioning holes (100) of the sealing frame with four positioning bolts, adjust the parallelism between the base of the portable milling machine and the protrusion (200) to within 0.2mm, position the tool in a rust-free place, and machine the inner and outer sides and top surface of the protrusion. Machining 1.0mm on each side of the outer and inner sides of the protrusion, and machining the arc corners with inner R70 to R71mm and outer R78 to R77mm to provide a reference surface for repair and shaping; 3) Perform localized pulsed argon arc welding on the deep corrosion pit (240). Before operation, check whether the welding machine is running normally and select metal wire XAB-MHEA-02; Set the process parameters as follows: welding current 130-150A, welding voltage 20-27V, welding speed 5.0-8.0 mm / s, and gas flow rate 10-15 L / min; Use a WS-300S welding machine to perform local pulsed argon arc welding on the deep corrosion pits that still exist after machining. The welding depth should be 0.5mm higher than the machined surface in step 2. 4) Localized fitter grinding: The weld overlay area with localized corrosion pits is ground by fitter grinding to form a consistent reference on the entire convex surface.

3. The additive repair method for damaged protruding edges of ship sealing frames as described in claim 2, characterized in that: The repair shaping (II) also includes: The on-site repair process is based on laser cladding and pulsed argon arc welding to form a corrosion-resistant layer (250) on the substrate of the part, with a certain machining allowance; first, the laser cladding of the straight edge of the protrusion (210) is carried out in segments for repair, and then the arc corner of the protrusion of the sealing frame is repaired by pulsed argon arc welding in segments. Laser cladding repair: Laser cladding repair is performed on the straight edge (210) of the convex ridge of the sealing ring. The specific steps are as follows: 1) Clean the oxides and oil stains from the surface to be clad before cladding; 2) Pre-operation checks, including whether the laser, robot, and powder feeder are operating normally, checking the air supply and pipeline tightness, and preparing metal powder material XAB-MHEA-02. 3) During the repair and forming process, the argon gas storage tank is opened, and a synchronous protection method is used to provide an argon gas protective environment for the cladding layer to prevent oxidation of the cladding material; 4) Set the process parameters: laser power 1450W, spot diameter 2.5mm, repair speed 700mm / min, overlap rate 50%, powder feeding amount 28g / min, protective airflow 15L / min, air pressure 0.5Mpa; 5) Determine the path program and develop a robot path control program based on the partitioned scanning forming strategy; perform scanning on the outer side, inner side and top of the convex edge from bottom to top, and use the robot cladding head to calibrate the red light to verify the trajectory. 6) Execute the program to complete the repair and shaping of the protruding edge; The outer surface (211), inner surface (212), and top surface (213) of the convex ridge are sequentially clad. Considering the long size of the convex ridge and its small height and width, the repair process is carried out in segments along the length direction. The outer surface (211), inner surface (212), and top surface (213) of the convex ridge are each divided into 10 segments. After the first segment is clad, the fourth segment is clad after two segments. After the fourth segment is clad, the seventh segment is clad after two segments. After the tenth segment is clad, the substrate temperature of the first segment has been cooled. Then the second segment is clad. The fifth segment is clad after cladding two segments apart, and so on, until the outer side (211), inner side (212), and top surface (213) of the protruding edge are all clad, and the segments are fully overlapped to form a corrosion-resistant layer (250). The method of using intermittent segmented laser cladding can, on the one hand, ensure that the substrate temperature does not exceed 100 degrees Celsius during the entire cladding process, effectively avoiding excessive substrate temperature, which may cause substrate deformation or / and changes in properties; on the other hand, it can reduce maintenance time, avoid maintenance interruption due to excessive substrate temperature during maintenance, reduce maintenance efficiency, and reduce the time waiting for the substrate to cool down. The robot performs construction along the length of the convex edge. Except for the arc corner, the cladding length is 740mm. From the interface position (230) between the arc corner and the straight edge of the convex edge to the middle position (214) of the straight edge of the convex edge, the cladding thickness gradually decreases, forming a corrosion-resistant layer (250) that is high on both sides and low in the middle. The cladding thickness x at the interface position between the arc corner and the straight edge of the convex edge can be obtained from the following formula: Where x is the cladding thickness at the interface position (230) between the arc corner and the straight edge of the convex ridge; H is the weld thickness at the middle position (224) of the arc corner of the convex ridge; h is the cladding thickness at the middle position (214) of the straight edge of the convex ridge; R is the radius of the arc at the middle position (224) of the arc corner of the convex ridge; L is the distance from the middle position (214) of the straight edge of the convex ridge to the interface position (230) between the arc corner and the straight edge of the convex ridge. The cladding thickness at the interface between the rounded corner and the straight edge of the convex ridge (230) is 1.9 mm; the cladding thickness at the middle position of the straight edge of the convex ridge (214) is 1.5 mm; the corrosion-resistant layer at the middle position of the rounded corner of the convex ridge (224) is the thickest, which is 2.0 mm; the corrosion-resistant layer at the interface between the rounded corner and the straight edge of the convex ridge (230) is 1.9 mm, and it is ensured that it fully overlaps with the laser cladding area; A corrosion-resistant layer is formed on the convex edge of the arc corner of the sealing ring by pulsed argon arc welding in sections: Pulse welding technology has the characteristics of short arc discharge time and small discharge range. In order to minimize the heat input to the protruding edge, the argon arc pulse welding is performed on each surface of the rounded corner (220) of the protruding edge by partitioned interval welding. 1) Clean the oxides and oil stains from the surface to be clad before welding; 2) Before operation, check whether the welding machine is running normally and select metal wire XAB-MHEA-02; 3) Set the process parameters: welding current 130-150A, welding voltage 20-27V, welding speed 5.0-8.0mm / s, gas flow rate 10-15L / min; 4) Manually operate the WS-300S welding machine to perform zoned and intermittent pulsed argon arc welding on the convex edge arc corner (220°): Partitioned welding: Divide each plane of the convex ridge arc corner into six evenly distributed areas: the first area (1), the second area (2), the third area (3), the fourth area (4), the fifth area (5), and the sixth area (6). The area on the top surface of the convex ridge arc corner is divided into two or three rows. Partitioned pulsed argon arc welding is performed. The manual operation first performs pulsed argon arc welding on the first area (1) in the order of the outer side (221), inner side (222), and top surface (223) of the convex ridge arc corner. Then, the second area (2) is welded in the order of the second area (2). Pulsed argon arc welding is performed, and so on, until the outer side (221), inner side (222), and top side (223) of the convex edge are all welded, and the complete overlap between each area is ensured to form a corrosion-resistant layer (250); when the last area of ​​the first group of areas (1) is welded, the first area of ​​the first group of areas (1) has cooled down, and when the second group of areas (2) is welded, heat will not accumulate on the substrate, causing local deformation; the interval between each weld can minimize the heat input to the convex edge; When performing zoned pulsed argon arc welding on each surface of the convex ridge arc corner, the welding thickness is gradually reduced from the middle position (224) of the convex ridge arc corner to the position (230) where it meets the straight edge of the convex ridge. That is, the corrosion-resistant layer at the middle position (224) of the convex ridge arc corner is higher than the corrosion-resistant layer at the interface position (230) between the arc corner and the straight edge of the convex ridge. The corrosion-resistant layer at the middle position (224) of the convex ridge arc corner has the largest thickness, which is 2.0 mm. The corrosion-resistant layer at the interface position (230) between the arc corner and the straight edge of the convex ridge is 1.9 mm, and it is ensured that it fully overlaps with the laser cladding area. Overall, from the middle position of the rounded corner of the convex ridge (224) to the middle position of the straight edge of the convex ridge (214), the thickness of the corrosion-resistant layer (250) decreases sequentially. The thickness of the corrosion-resistant layer (250) at the middle position of the rounded corner of the convex ridge (224) is the largest, at 2.0 mm; the thickness of the corrosion-resistant layer (250) at the middle position of the straight edge of the convex ridge (214) is the smallest, at 1.5 mm. By increasing the thickness of the repair layer at the rounded corner of the convex ridge of the sealing frame, the corrosion resistance of the rounded corner of the convex ridge of the sealing frame is improved, the service life of the sealing frame is extended, and the maintenance frequency is reduced.

4. The additive repair method for damaged protruding edges of ship sealing frames as described in claim 3, characterized in that: The post-processing (III) includes portable milling and bench polishing processes: A portable milling machine performs milling on the outer surface (211), inner surface (212), and top surface (213) of the straight edge of the protruding ridge after laser cladding and pulse welding, and the outer surface (221), inner surface (222), and top surface (223) of the rounded corner of the protruding ridge. This ensures that the corrosion-resistant layer (250) at the middle position (224) of the rounded corner of the protruding ridge is 1.5 mm thick, and the corrosion-resistant layer (250) at the middle position (214) of the straight edge of the protruding ridge is 1.0 mm thick. The corrosion-resistant layer (250) on the protruding ridge of the sealing ring extends from the rounded corner of the protruding ridge. A smooth slope is formed from the middle position (224) of the arc corner to the middle position (214) of the straight edge of the convex ridge; from the middle position (224) of the arc corner of the convex ridge to the middle position (214) of the straight edge of the convex ridge, it is in the shape of a quadrangular frustum; the outer and inner sides of the convex ridge are machined to ensure that the width of the convex ridge is 8.0±0.2mm, the height of the convex ridge is machined to the range of 10.5 to 10.0±0.2mm, and the inner R of the arc corner of the sealing frame is machined to the range of 69.5mm to 69.6mm and the outer R is 78.5mm to 78.6mm. Grind the corners and tool marks that cannot be reached by a portable milling machine, and polish the entire protrusion to make it flat and smooth.

5. The additive repair method for damaged protruding edges of ship sealing frames as described in claim 4, characterized in that: The inspection (IV) involves performing dimensional and quality inspections on the repaired parts to ensure they meet the technical requirements. The repaired seal frame ridges showed that the laser repair effectively restored the ridges' dimensions and watertightness.

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