Metallurgical equipment bull gear repairing method based on additive manufacturing

Abstract

The invention relates to the technical field of gear repairing, in particular to a metallurgical equipment bull gear repairing method based on additive manufacturing, which comprises the following steps of: disassembling a bull gear and fixing the bull gear by using a gear clamp; the area, where abrasion, pitting corrosion or deformation occurs, of the tooth surface of the large gear is cleaned; then, cutting treatment is carried out on the abraded, pitted or deformed area; pre-welding preheating is conducted on base metal of the cutting part through a flame spray gun, and then layer-by-layer additive cladding welding is conducted from the bottommost layer of the cutting part through a welding wire; then the surface is polished to be flat; according to the invention, the problems of abrasion, pitting corrosion and plastic deformation of the tooth surface of the bull gear in metallurgical equipment after working for a period of time are solved; the bull gear to be repaired is reinforced and corrected by utilizing an additive manufacturing technology, so that the performance of the bull gear in metallurgical equipment is enhanced, and the production efficiency is improved; the situation that the whole gear is replaced due to damage of one or more teeth in the large gear of the metallurgical equipment is avoided, the overhaul efficiency is improved, and the overhaul cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of gear repair, and in particular to a method for repairing a large gear of metallurgical equipment based on additive manufacturing. Background Art

[0002] In the metallurgical industry, stackers, rotary distributors, slag treatment drum filters and other equipment are equipped with large gears. The manufacturing cost of large gears is high, and the transportation and installation are difficult and labor-intensive. However, due to the poor working environment, large gears are prone to wear and plastic deformation in the working state. For example, fine iron filings in the lubricating oil cause abrasive wear on the tooth surface, wear caused by collision between gears, adhesive wear between tooth surfaces due to different viscosities of the lubricating fluid, pitting on the tooth surface after long-term operation, tooth surface bonding and plastic deformation on the tooth surface after lubrication failure. These Wear, pitting and plastic deformation can all cause the problem of meshing failure between gears, which will not only reduce the efficiency of mechanical transmission, but also pose a great safety hazard, greatly increasing the risk factor in production. In the prior art, when plastic deformation, wear and pitting occur on individual tooth surfaces of large gears, if it does not affect the use, it is usually chosen to continue to be used. When it affects the use of the equipment or the equipment has an operating failure, it is usually chosen to replace the entire large gear. The overall replacement cost of the component is high, which is not conducive to the company's economic benefits. Therefore, in line with the concept of being more economical and environmentally friendly, we have developed a large gear repair method for metallurgical equipment based on additive manufacturing. Summary of the invention

[0003] In view of the deficiencies in the prior art, an object of the present invention is to provide a method for repairing large gears of metallurgical equipment based on additive manufacturing, which avoids the need for overall replacement of large gears and saves equipment maintenance costs.

[0004] The technical solution adopted by the present invention to solve its technical problem is:

[0005] A method for repairing a large gear of metallurgical equipment based on additive manufacturing comprises the following steps:

[0006] S1: Remove the large gear and fix it with a gear fixture. When fixing, adjust the worn, pitted or deformed area of ​​the large gear to a position that is convenient for the staff to repair;

[0007] S2: Clean the areas on the gear tooth surface that are worn, pitted or deformed. First, remove the dust, rust and other surface stains and lubricants. Then, cut the worn, pitted or deformed areas until the base metal is exposed.

[0008] S3: Use a flame spray gun to preheat the base metal of the cutting part before welding, and then use welding wire to add material layer by layer from the bottom layer of the cutting part;

[0009] S4: After cladding welding, air cooling is performed and then the surface is polished to be smooth to obtain a repaired gear.

[0010] Preferably, a further technical solution of the present invention is:

[0011] Preferably, in step S2, when the worn, pitted or deformed area is cut, after the worn, pitted or deformed area is cut down, it is further cut down to a depth of 1-2 mm.

[0012] Preferably, in step S3, for a cutting depth less than 3 mm, single-layer cladding welding is performed with welding wire; for a cutting depth less than 5 mm and greater than or equal to 3 mm, two-layer cladding welding is performed with welding wire; for a cutting depth less than 10 mm and greater than or equal to 5 mm, three-layer cladding welding is performed with welding wire.

[0013] Preferably, in step S1, the gear fixture includes a sliding seat, a fixed rod is fixed at one end of the sliding seat, a sliding rod is slidably connected to the sliding seat, and a support plate is respectively arranged on the fixed rod and the sliding rod; a rotating rod is rotatably connected to the support plate, the rotating rod penetrates the support plate, and the rotating rod is located at one end of the outer side of the two support plates and is slidably sleeved with a sleeve, and a limit seat is provided at one end of the sleeve away from the support plate, a limit rod is provided on the limit seat, and a limit hole is provided on the support plate corresponding to the limit rod; when the sliding sleeve is inserted into the limit hole, the rotating rod cannot rotate, and when the limit rod is pulled out of the limit hole, the rotating rod can rotate again; a plug or a slot is provided at the other end of the rotating rod between the two support plates, and one of the two rotating rods is provided with a plug and the other is provided with a slot; it also includes an adjusting rod, the adjusting rod penetrates the fixed rod and the sliding rod, and a threaded adjustment part is provided on the adjusting rod, the adjusting rod is rotatably connected to the fixed rod and is threadedly connected to the sliding rod.

[0014] Preferably, an anti-slip rubber layer is provided on the outer side of the plug.

[0015] Preferably, a rotating handle is provided at one end of the adjusting rod.

[0016] Preferably, the process of fixing the large gear with the gear fixture is as follows:

[0017] S101: The large gear to be repaired is put on the plug, and then the adjustment rod is rotated to slide the sliding rod on the sliding seat through the threaded adjustment part until the plug is inserted into the slot, and the two rotating rods work together to clamp the large gear to be repaired;

[0018] S102: Pull the limit rod out of the limit hole, rotate the rotating rod, and adjust the area of ​​the large gear where wear, pitting or deformation occurs to a position that is convenient for the staff to repair;

[0019] S103: Insert the limit rod into the limit hole to fix the large gear.

[0020] Compared with the prior art, the present invention adopting the above technical solution has the following outstanding features:

[0021] The patent of this invention solves the problem that the tooth surface of the large gear in the metallurgical equipment is prone to wear, pitting and plastic deformation after working for a period of time; the large gear of the metallurgical equipment that has been running-in is strengthened and corrected by using additive manufacturing technology, thereby enhancing the performance of the large gear in the metallurgical equipment and improving production efficiency; it avoids the situation in which the entire gear needs to be replaced due to damage to one or several teeth in the large gear of the metallurgical equipment, thereby improving maintenance efficiency and reducing maintenance costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 is a schematic structural diagram of an embodiment of the present invention;

[0023] Figure 2 is a schematic structural diagram of an embodiment of the present invention;

[0024] Figure 3 It is a single-layer single-pass cladding morphology in the embodiment of the present invention;

[0025] Figure 4 is a metallographic structure photograph of the weld area in an embodiment of the present invention;

[0026] Figure 5 This is an image of the weld under SEM observation in an embodiment of the present invention.

[0027] Description of reference numerals: 1, slide seat; 2, fixed rod; 3, sliding rod; 4, support plate; 5, rotating rod; 501, linear slide groove; 6, sleeve; 7, limit seat; 8, limit rod; 9, limit hole; 10, plug; 11, slot; 12, adjustment rod; 13, rotating handle; 14, large gear; Figure 5 Middle a is the SEM clear image of the weld; Figure 5 (b) is the SEM dark field image of the weld. DETAILED DESCRIPTION

[0028] The present invention is further described below in conjunction with specific embodiments, the purpose of which is only to provide a better understanding of the content of the present invention. Therefore, the examples given do not limit the protection scope of the present invention.

[0029] This embodiment provides a method for repairing a large gear of metallurgical equipment based on additive manufacturing, comprising the following steps:

[0030] S1: Remove the large gear 14 and fix it with a gear fixture. When fixing, the area of ​​the large gear 14 where wear, pitting or deformation occurs needs to be adjusted to a position that is convenient for the staff to repair.

[0031] S2: Clean the area where the tooth surface of the large gear 14 is worn, pitted or deformed. First, clean the dust, rust and other surface stains and lubricating fluid; then, cut the worn, pitted or deformed area until the base metal is exposed; when cutting the worn, pitted or deformed area, after cutting off the worn, pitted or deformed area, the surface metal is prone to fatigue damage due to the fatigue force under the working state of the gear, so it is necessary to cut down 1-2mm deeper.

[0032] S3: Use a flame spray gun to preheat the base metal of the cutting part before welding, the heat temperature is between 180-200℃; then use welding wire to add material layer by layer from the bottom layer of the cutting part, and the temperature between passes should not be lower than 100℃ during the cladding welding process; for cutting depth less than 3mm, such as Figure 3 , use welding wire for single-layer single-pass cladding welding; for cutting depth less than 5mm and greater than or equal to 3mm, use welding wire for two-layer cladding welding; for cutting depth less than 10mm and greater than or equal to 5mm, use welding wire for three-layer cladding welding.

[0033] In this embodiment, the additive cladding welding adopts ER91T1-G high-strength welding wire for welding, with a welding voltage of 30V, a welding current of 280A, and a welding speed of 0.2m / min. After testing, the cladding material under the above parameters has excellent corrosion resistance and is free of welding defects such as undercut, pores, and inclusions.

[0034]

[0035] Table 1

[0036]

[0037] Table 2

[0038] As shown in Table 1 (Chemical composition of ER91 T1-G (mass fraction %)) and Table 2 (Mechanical properties of ER91 T1-G deposited metal), since the weld structure is a combination of acicular ferrite, pre-symbiotic ferrite and side lath ferrite, it has extremely strong wear resistance and corrosion resistance, and can improve the working life of the tooth surface of large gear 14 to a limited extent.

[0039] S4: After cladding welding, air cooling is required for at least eight hours, and then the surface is polished to obtain a repaired gear.

[0040] The method solves the problem that the tooth surface of the large gear 14 in the metallurgical equipment is prone to wear, pitting and plastic deformation after working for a period of time; the large gear 14 of the metallurgical equipment that has been run-in is strengthened and corrected by using additive manufacturing technology, thereby enhancing the performance of the large gear 14 in the metallurgical equipment and improving production efficiency; it avoids the situation in which the entire gear 14 of the metallurgical equipment needs to be replaced due to damage to one or several teeth, thereby improving maintenance efficiency and reducing maintenance costs.

[0041] like Figure 1 , Figure 2 As shown, in step S1, the gear fixture includes a slide 1, a fixed rod 2 is fixed at one end of the slide 1, a sliding rod 3 is slidably connected in the slide 1, and a slider adapted to the slide groove on the slide 1 is arranged at the lower end of the sliding rod 3; a support plate 4 is arranged on each of the fixed rod 2 and the sliding rod 3; a rotating rod 5 is rotatably connected to the support plate 4 through a bearing, and the rotating rod 5 penetrates the support plate 4, and a sleeve 6 is slidably sleeved at one end of the rotating rod 5 located at the outer side of the two support plates 4, and a limit seat 7 is arranged at the end of the sleeve 6 away from the support plate 4, and a limit rod 8 is arranged on the limit seat 7, and the support plate 4 is provided with a plurality of support plates 4. A limiting hole 9 is set corresponding to the limiting rod 8; when the limiting rod 8 is inserted into the limiting hole 9 of the sliding sleeve 6, the rotating rod 5 cannot rotate, and when the limiting rod 8 is pulled out of the limiting hole 9, the rotating rod 5 can rotate again; the other end of the rotating rod 5 located between the two support plates 4 is set with a plug 10 or a slot 11, and one of the two rotating rods 5 is set with a plug 10, and the other is set with a slot 11; it also includes an adjusting rod 12, the adjusting rod 12 is set through the fixed rod 2 and the sliding rod 3, and a threaded adjustment part is set on the adjusting rod 12, the adjusting rod 12 is rotatably connected to the fixed rod 2 through a bearing, and is threadedly connected to the sliding rod 3.

[0042] A linear slide 501 is provided on one end of the rotating rod 5 located outside the two support plates 4 , and a slide bar adapted to the linear slide 501 is provided in the sleeve 6 . The sleeve 6 is slidably connected to the rotating rod 5 through the linear slide 501 and the slide bar.

[0043] Furthermore, in order to prevent the plug 10 and the slot 11 from slipping, a non-slip rubber layer is provided on the outside of the plug 10 ; in order to facilitate the staff to rotate the adjustment rod 12 , a rotating handle 13 is provided at one end of the adjustment rod 12 .

[0044] The process of fixing the large gear 14 with the gear fixture is as follows:

[0045] S101: Put the large gear 14 to be repaired on the plug 10, then rotate the adjusting rod 12, and slide the sliding rod 3 on the sliding seat 1 through the threaded adjustment part until the plug 10 is inserted into the slot 11, and the two rotating rods 5 work together to clamp the large gear 14 to be repaired.

[0046] S102: Pull the limiting rod 8 out of the limiting hole 9, rotate the rotating rod 5, and adjust the area of ​​the large gear 14 where wear, pitting or deformation occurs to a position that is convenient for the staff to repair.

[0047] S103: Insert the limiting rod 8 into the limiting hole 9 to fix the large gear 14.

[0048] The above description is only the preferred embodiment of the present invention, and does not limit the scope of rights of the present invention. All equivalent changes made by using the contents of the present invention specification and its drawings are included in the scope of rights of the present invention.

Claims

1. A method for repairing large gears of metallurgical equipment based on additive manufacturing, characterized in that: The steps include: S1: Remove the large gear (14) and fix it with a gear fixture. When fixing, adjust the area of ​​the large gear (14) that is worn, pitted or deformed to a position that is convenient for the staff to repair; S2: cleaning the area on the tooth surface of the large gear (14) where wear, pitting or deformation occurs, first cleaning the surface stains such as dust, rust and lubricating fluid; then cutting the area where wear, pitting or deformation occurs, cutting until the base metal is exposed; S3: Use a flame spray gun to preheat the base metal of the cutting part before welding, and then use welding wire to add material layer by layer from the bottom layer of the cutting part; S4: After cladding welding, air cooling is performed and then the surface is polished to be smooth to obtain a repaired gear.

2. The method for repairing a large gear of metallurgical equipment based on additive manufacturing according to claim 1, characterized in that: In step S2, when the worn, pitted or deformed area is cut, after the worn, pitted or deformed area is cut down, it is further cut down to a depth of 1-2 mm.

3. The method for repairing a large gear of metallurgical equipment based on additive manufacturing according to claim 1, characterized in that: In step S3, for cutting depths less than 3 mm, single-layer cladding welding is performed with welding wire; for cutting depths less than 5 mm and greater than or equal to 3 mm, two-layer cladding welding is performed with welding wire; for cutting depths less than 10 mm and greater than or equal to 5 mm, three-layer cladding welding is performed with welding wire.

4. The method for repairing a large gear of metallurgical equipment based on additive manufacturing according to claim 1, characterized in that: In step S1, the gear fixture comprises a slide seat (1), a fixed rod (2) is fixed at one end of the slide seat (1), a sliding rod (3) is slidably connected in the slide seat (1), and a support plate (4) is respectively provided on the fixed rod (2) and the sliding rod (3); A rotating rod (5) is rotatably connected to the support plate (4), and the rotating rod (5) penetrates the support plate (4). A sleeve (6) is slidably sleeved on one end of the rotating rod (5) located outside the two support plates (4). A limiting seat (7) is provided on the end of the sleeve (6) away from the support plate (4). A limiting rod (8) is provided on the limiting seat (7), and a limiting hole (9) is provided on the support plate (4) corresponding to the limiting rod (8); when the sliding sleeve (6) and the limiting rod (8) are inserted into the limiting hole (9), the rotating rod (5) cannot rotate, and when the limiting rod (8) is pulled out of the limiting hole (9), the rotating rod (5) can rotate again; a plug (10) or a slot (11) is provided on the other end of the rotating rod (5) located between the two support plates (4), and one of the two rotating rods (5) is provided with a plug (10) and the other is provided with a slot (11); The device also comprises an adjusting rod (12), the adjusting rod (12) being arranged to penetrate the fixed rod (2) and the sliding rod (3), a threaded adjusting portion being arranged on the adjusting rod (12), the adjusting rod (12) being rotatably connected to the fixed rod (2), and being threadedly connected to the sliding rod (3).

5. The method for repairing a large gear of metallurgical equipment based on additive manufacturing according to claim 4, characterized in that: An anti-slip rubber layer is provided on the outer side of the plug (10).

6. The method for repairing a large gear of metallurgical equipment based on additive manufacturing according to claim 4, characterized in that: A rotating handle (13) is provided at one end of the adjusting rod (12).

7. The method for repairing a large gear of metallurgical equipment based on additive manufacturing according to claim 4, characterized in that: The process of fixing the large gear (14) with the gear fixture is as follows: S101: The large gear (14) to be repaired is placed on the plug (10), and then the adjusting rod (12) is rotated to slide the sliding rod (3) on the sliding seat (1) through the threaded adjusting portion until the plug (10) is inserted into the slot (11), and the two rotating rods (5) work together to clamp the large gear (14) to be repaired; S102: Pull the limit rod (8) out of the limit hole (9), rotate the rotating rod (5), and adjust the area of ​​the large gear (14) where wear, pitting or deformation occurs to a position that is convenient for the staff to repair; S103: Insert the limiting rod (8) into the limiting hole (9) to fix the large gear (14).

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