CN111151968B - Axial additive manufacturing method for repairing continuous casting roller - Google Patents
Axial additive manufacturing method for repairing continuous casting roller Download PDFInfo
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- CN111151968B CN111151968B CN202010018054.6A CN202010018054A CN111151968B CN 111151968 B CN111151968 B CN 111151968B CN 202010018054 A CN202010018054 A CN 202010018054A CN 111151968 B CN111151968 B CN 111151968B
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P6/00—Restoring or reconditioning objects
Abstract
The invention discloses a method for repairing an axial additive of a continuous casting roller, belonging to the technical field of repairing of mechanical parts, wherein the method for preparing the axial additive comprises the following steps of 1, turning a roller surface, and removing a roller surface corrosion fatigue layer of the continuous casting roller; step 2, turning end faces, and turning the two end faces to a certain size respectively; step 3, welding patches, spot-welding the patches on two axial end surfaces of the turned continuous casting roller, step 4, integrally overlaying the roller surface, and integrally overlaying a wear-resistant alloy layer on the roller surface of the continuous casting roller in a submerged arc mode; step 5, machining and reshaping, namely machining and reshaping the air-cooled continuous casting roller; step 6, inspecting, namely performing surface dye inspection on the machined continuous casting roller, and detecting whether the working surface of the continuous casting roller has defects such as cracks; and 7, packaging, namely coating the qualified continuous casting roller with anti-rust oil, and packaging for later use.
Description
Technical Field
The invention relates to a method for repairing an axial additive of a continuous casting roller, and belongs to the technical field of repairing of mechanical parts.
Background
The continuous casting rolls are important parts of continuous casting machines and perform the functions of carrying and driving the billet and the moving blank mold. When the continuous casting device is used, the continuous casting roller is continuously contacted with a red hot casting blank which is not solidified inside, so that the continuous casting roller not only repeatedly bears the alternating cold and hot impact circulation action of local high-temperature heating and water cooling, but also bears the alternating mechanical stress action of slab bulging force and static pressure, and the working condition is severe. After the roller surface is used for a period of time, the roller surface often has conditions of reticular cracks, oxidation corrosion, burning loss, abrasion and the like with different degrees, so that the failure is caused, and the quality of billet products and the continuous production of steel enterprises are seriously influenced.
Aiming at the failure mode of the continuous casting roller, in order to save materials, the damaged continuous casting roller surface is widely repaired by adopting the processes of submerged arc surfacing, open arc surfacing, spray welding, plasma surfacing, laser cladding and the like at present, meanwhile, the burnt and damaged bearing, rotary joint and shoe seat are replaced, the remanufactured continuous casting roller can be continuously used, and the waste of materials is reduced. However, in actual repair, it is found that the axial dimension of the continuous casting roll repaired more than twice is continuously reduced because the end surface of the continuous casting roll is perpendicular to the roll surface, the end surface of the continuous casting roll is a ring surface due to the need of installing a bearing seat and the like, the wall thickness of a single side is generally only about 5mm, when surfacing, plasma and spray welding repair is adopted, the phenomenon of 'undercut' often occurs, namely the edge of the end surface of the continuous casting roll is often melted and collapsed, and when subsequent machining and replication are carried out, the continuous casting roll is turned shorter to ensure the appearance and surface form and position tolerance of the continuous casting roll. Generally, the continuous casting roller is subjected to surfacing repair once, and the length of the continuous casting roller is reduced by 1 mm-2 mm at least. After 2-5 times of repair, the length of the continuous casting roll is 5-8 mm less than the standard size, so that the gap between the end face of the continuous casting roll and a bearing seat is enlarged, impurities such as billet oxide skin easily enter a bearing in the bearing seat, and the bearing is further abraded to lose efficacy in a short period. Because the wall thickness of the end face of the continuous casting roller is thin, the end face is easy to deform by adopting traditional surfacing welding and manual welding for additive manufacturing, the sealing and assembly of the continuous casting roller are affected, and the repair yield and the efficiency in actual production are low.
Disclosure of Invention
The invention provides a preparation method for repairing the axial additive of the continuous casting roller, which can increase the repairable times of the continuous casting roller and reduce the waste of materials.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
a method for repairing axial additive of a continuous casting roller comprises the following steps:
step 1, turning a roll surface: turning a single side of the roll surface of the continuous casting roll to a certain size in combination with the roll surface abrasion condition, and removing a roll surface corrosion fatigue layer of the continuous casting roll;
step 2, turning end faces: turning the two end surfaces to a certain size respectively by combining the damage conditions of the two axial end surfaces of the continuous casting roll;
step 3, welding patches: spot-welding patches on two axial end faces of the turned continuous casting roll, welding the patches and the end faces of the continuous casting roll together through a plurality of welding spots at equal intervals on the roll surface, wherein the patches are annular patches, the outer diameter of each annular patch is the same as the diameter of the continuous casting roll after the fatigue layer is turned, and the inner diameter of each annular patch is 8-12 mm smaller than the outer diameter of the continuous casting roll after the fatigue layer is turned;
step 4, integral surfacing of the roller surface: carrying out submerged arc surfacing on the whole of the roll surface of the continuous casting roll, and carrying out air cooling on the whole continuous casting roll after a certain thickness is formed on a single side by surfacing;
and 5, machining and copying: machining and copying the continuous casting roll after air cooling, wherein the length and the diameter of the continuous casting roll after copying are equal to the standard size of the continuous casting roll;
step 6, checking: carrying out surface dye inspection on the machined continuous casting roller, and detecting whether the working surface of the continuous casting roller has defects such as cracks;
and 7, packaging: and (4) coating the qualified continuous casting roller with anti-rust oil, and packaging for later use.
The technical scheme of the invention is further improved as follows: the thickness of the annular patch in the step 3 is larger than the turning size of the end surface in the step 2, and the thickness of the single-side surfacing of the roll surface in the step 4 is larger than the single-side turning size of the roll surface in the step 1.
The technical scheme of the invention is further improved as follows: annular paster thickness is 5mm ~7mm, and the facing cut size is 3mm ~5mm, and the unilateral build-up welding thickness of roll surface is 4mm ~5mm, and the unilateral turning size of roll surface is 2mm ~3 mm.
The technical scheme of the invention is further improved as follows: and 3, the material of the patch in the step 3 is 42CrMo steel.
The technical scheme of the invention is further improved as follows: and 4, D507, the diameter of the welding wire is 3.2mm, and SJ102 is used for carrying out submerged arc surfacing on the whole roller surface of the continuous casting roller.
The technical scheme of the invention is further improved as follows: the interval between the welding points in step 3 is 60 degrees or 90 degrees.
The technical scheme of the invention is further improved as follows: in the step 4, when the wear-resistant alloy layer is subjected to submerged arc surfacing on the whole roll surface of the continuous casting roll, the current is 290-320A, the direct-current polarity positive voltage is 29-32V, and the welding speed is 140-220 mm/min.
Due to the adoption of the technical scheme, the invention has the technical progress that:
the preparation method comprises seven steps of turning the roll surface, turning the end surface, welding patches, integrally overlaying the roll surface, machining and reshaping, inspecting and packaging, and can increase the repairable times of the continuous casting roll and reduce the waste of materials.
The turned continuous casting roll is subjected to spot welding of patches on two axial end surfaces, so that the problem that the edge of the end surface of the continuous casting roll is melted and collapsed frequently when the conventional surfacing welding, plasma and spray welding repair is adopted due to the fact that the end surface of the continuous casting roll is an annular surface and the thickness of a single side wall is thin is solved, the problem that the repaired continuous casting roll is scrapped due to thermal deformation caused when the conventional surfacing welding and manual electric arc welding are used for material increase of the end surface of the continuous casting roll is solved, the repair efficiency is improved, and the repair cost is reduced; meanwhile, the problems that the length of the continuous casting roll is smaller than the standard size after the continuous casting roll is repaired for 2-5 times, so that the gap between the end surface of the continuous casting roll and a bearing seat is enlarged, and impurities such as billet oxide skin easily enter a bearing in the bearing seat to cause short-term grinding failure of the bearing are solved.
The submerged arc surfacing welding wear-resistant alloy layer has the advantages of no pollution in the welding process, no burning loss of the alloy, high utilization rate, difficulty in cracking in welding, adoption of direct-current reverse connection for the welding wire D507, air quenching property of the surfacing welding layer, no need of heat treatment, uniform hardness, easiness in slag removal due to the use of SJ102 flux and low flux consumption.
Detailed Description
The present invention will be described in further detail with reference to the following examples:
a method for repairing axial additive of a continuous casting roller comprises the following steps:
step 1, turning a roll surface: turning the single side of the roll surface of the continuous casting roll to a certain size in combination with the roll surface abrasion condition, wherein the size of the single side of the roll surface is 2-3 mm, and removing a roll surface corrosion fatigue layer of the continuous casting roll;
step 2, turning end faces: turning the two end faces to a certain size in combination with the damage condition of the two axial end faces of the continuous casting roll, wherein the turning size of the end faces is 3-5 mm;
step 3, welding patches: spot welding patches on two axial end faces of the turned continuous casting roll, welding the patches and the end faces of the continuous casting roll together through a plurality of welding spots at equal intervals on the roll surface, wherein when the interval between the welding spots is 60 degrees, the total number of the welding spots is 6, when the interval between the welding spots is 90 degrees, the total number of the welding spots is 4, the patches are made of 42CrMo steel, the patches are annular patches, the outer diameter of each annular patch is the same as the diameter of the continuous casting roll after the fatigue layer is turned, the inner diameter of each annular patch is 8-12 mm smaller than the outer diameter of the continuous casting roll, and the thickness of each annular patch is 5-7 mm;
step 4, integral surfacing of the roller surface: carrying out air cooling on the whole continuous casting roller after a certain thickness is subjected to single-side surfacing, wherein the single-side surfacing thickness of the roller surface is 4-5 mm, a welding wire used for the whole submerged arc surfacing wear-resistant alloy layer of the roller surface of the continuous casting roller is D507, the diameter of the welding wire is 3.2mm, a welding flux is SJ102, the current is 290-320A, the direct-current polarity positive voltage is 29-32V, and the welding speed is 140-220 mm/min;
and 5, machining and copying: machining and copying the continuous casting roll after air cooling, wherein the length and the diameter of the continuous casting roll after copying are equal to the standard size of the continuous casting roll;
step 6, checking: carrying out surface dye inspection on the machined continuous casting roller, and detecting whether the working surface of the continuous casting roller has defects such as cracks;
and 7, packaging: and (4) coating the qualified continuous casting roller with anti-rust oil, and packaging for later use.
Example 1
The axial additive manufacturing method for repairing the continuous casting roller comprises the following steps:
in the step 1: the unilateral turning size of the roll surface is 2 mm;
in the step 2: the turning sizes of the two end faces are both 3 mm;
in the step 3: when the interval between the welding spots is 90 degrees, the total number of the welding spots is 4, the inner diameter of the annular patch is 10mm smaller than the outer diameter, and the thickness of the annular patch is 5 mm;
in the step 4: the thickness of the single-side surfacing of the roller surface is 4mm, the current is 290A when the wear-resistant alloy layer is subjected to submerged arc surfacing on the whole roller surface of the continuous casting roller, the direct-current polarity positive voltage is 29V, and the welding speed is 140 mm/min.
Example 2
This example is the same as the process steps in example 1, and differs from example 1 in that:
in the step 1: 3mm of unilateral turning size of the roll surface;
in the step 2: the turning sizes of the two end faces are both 5 mm;
in the step 3: when the interval between the welding points is 60 degrees, the total number of the welding points is 6, the inner diameter of the annular patch is 12mm smaller than the outer diameter, and the thickness of the annular patch is 7 mm;
in the step 4: the thickness of the single-side surfacing of the roller surface is 5mm, the current is 320A when the wear-resistant alloy layer is subjected to submerged arc surfacing on the whole roller surface of the continuous casting roller, the direct-current polarity positive voltage is 32V, and the welding speed is 220 mm/min.
Example 3
This example is the same as the process steps in example 1, and differs from example 1 in that:
in the step 2: the turning sizes of the two end faces are both 5 mm;
in the step 3: the inner diameter of the annular patch is 8mm smaller than the outer diameter of the annular patch, and the thickness of the annular patch is 7 mm;
in the step 4: the welding speed was 180 mm/min.
Example 4
This example is the same as the process steps in example 1, and differs from example 1 in that:
in the step 1: 3mm of unilateral turning size of the roll surface;
in the step 2: the turning sizes of the two end faces are both 5 mm;
in the step 3: the thickness of the annular patch is 7 mm;
in the step 4: the thickness of the single-side surfacing of the roller surface is 5mm, the current is 310A when the wear-resistant alloy layer is subjected to submerged arc surfacing on the whole roller surface of the continuous casting roller, the direct-current polarity positive voltage is 31V, and the welding speed is 200 mm/min.
Example 5
This example is the same as the process steps in example 1, and differs from example 1 in that:
in the step 1: 3mm of unilateral turning size of the roll surface;
in the step 2: the turning sizes of the two end faces are both 4 mm;
in the step 3: the thickness of the annular patch is 6 mm;
in the step 4: the thickness of the single-side surfacing of the roller surface is 5mm, the current is 310A when the wear-resistant alloy layer is subjected to submerged arc surfacing on the whole roller surface of the continuous casting roller, the direct-current polarity positive voltage is 31V, and the welding speed is 200 mm/min.
Example 6
This example is the same as the process steps in example 1, and differs from example 1 in that:
and the welding speed is 220mm/min when the wear-resistant alloy layer is integrally submerged-arc welded on the roll surface of the continuous casting roll.
Example 7
This example is the same as the process steps in example 1, and differs from example 1 in that:
in the step 1: 3mm of unilateral turning size of the roll surface;
in the step 2: the turning sizes of the two end faces are both 4 mm;
in the step 3: the thickness of the annular patch is 6 mm;
in the step 4: the thickness of the single-side surfacing of the roller surface is 5mm, the current is 320A when the wear-resistant alloy layer is subjected to submerged arc surfacing on the whole roller surface of the continuous casting roller, the direct-current polarity positive voltage is 32V, and the welding speed is 220 mm/min.
Example 8
This example is the same as the process steps in example 1, and differs from example 1 in that:
in the step 1: 3mm of unilateral turning size of the roll surface;
in the step 2: the turning sizes of the two end faces are both 5 mm;
in the step 3: the thickness of the annular patch is 7 mm;
in the step 4: the thickness of the single-side surfacing of the roller surface is 5mm, the current is 300A when the wear-resistant alloy layer is subjected to submerged arc surfacing on the whole roller surface of the continuous casting roller, the direct-current polarity positive voltage is 30V, and the welding speed is 190 mm/min.
The principle and the implementation mode of the invention are explained by applying a specific example, and the description of the embodiment is only used for helping to understand the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In view of the above, the present disclosure should not be construed as limiting the invention.
Claims (4)
1. The axial additive manufacturing method for repairing the continuous casting roller is characterized by comprising the following steps: the method comprises the following steps:
step 1, turning a roll surface: turning a single side of the roll surface of the continuous casting roll to a certain size in combination with the roll surface abrasion condition, and removing a roll surface corrosion fatigue layer of the continuous casting roll; the unilateral turning size of the roll surface is 2 mm-3 mm;
step 2, turning end faces: turning the two end surfaces to a certain size respectively by combining the damage conditions of the two axial end surfaces of the continuous casting roll; the end face turning size is 3 mm-5 mm;
step 3, welding patches: spot-welding patches on two axial end faces of the turned continuous casting roll, welding the patches and the end faces of the continuous casting roll together through a plurality of welding spots at equal intervals on the roll surface, wherein the patches are annular patches, the outer diameter of each annular patch is the same as the diameter of the continuous casting roll after the fatigue layer is turned, and the inner diameter of each annular patch is 8-12 mm smaller than the outer diameter of the continuous casting roll after the fatigue layer is turned; the thickness of the annular patch is larger than the turning size of the end face in the step 2; the thickness of the annular patch is 5 mm-7 mm; the material of the patch is 42CrMo steel;
step 4, integral surfacing of the roller surface: carrying out submerged arc surfacing on the whole of the roll surface of the continuous casting roll, and carrying out air cooling on the whole continuous casting roll after a certain thickness is formed on a single side by surfacing; the thickness of the single-side surfacing of the roll surface is larger than the size of the single-side turning of the roll surface in the step 1;
and 5, machining and copying: machining and copying the continuous casting roll after air cooling, wherein the length and the diameter of the continuous casting roll after copying are equal to the standard size of the continuous casting roll;
step 6, checking: carrying out surface dye inspection on the machined continuous casting roller, and detecting whether the working surface of the continuous casting roller has defects such as cracks;
and 7, packaging: and (4) coating the qualified continuous casting roller with anti-rust oil, and packaging for later use.
2. The axial additive manufacturing method for repairing the continuous casting roller according to claim 1, characterized by comprising the following steps: and 4, D507, the diameter of the welding wire is 3.2mm, and SJ102 is used for carrying out submerged arc surfacing on the whole roller surface of the continuous casting roller.
3. The axial additive manufacturing method for repairing the continuous casting roller according to claim 1, characterized by comprising the following steps: the interval between the welding points in step 3 is 60 degrees or 90 degrees.
4. The axial additive manufacturing method for repairing the continuous casting roller according to claim 1, characterized by comprising the following steps: in the step 4, when the wear-resistant alloy layer is subjected to submerged arc surfacing on the whole roll surface of the continuous casting roll, the current is 290-320A, the direct-current polarity positive voltage is 29-32V, and the welding speed is 140-220 mm/min.
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| CN202010018054.6A CN111151968B (en) | 2020-01-08 | 2020-01-08 | Axial additive manufacturing method for repairing continuous casting roller |
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| CN111151968B true CN111151968B (en) | 2021-07-30 |
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| CN105689848A (en) * | 2014-11-28 | 2016-06-22 | 重庆伊曼环保设备有限公司 | Surfacing repair process for extrusion roll |
| CN105750812A (en) * | 2014-12-15 | 2016-07-13 | 重庆迅升机车配件有限公司 | Converter slab continuous casting roller bead welding repairing technology |
| CN109759772A (en) * | 2019-01-16 | 2019-05-17 | 燕山大学 | A kind of fast repairing method with helicla flute Continuous Casting Rolls |
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2020
- 2020-01-08 CN CN202010018054.6A patent/CN111151968B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103350316A (en) * | 2013-07-15 | 2013-10-16 | 莱芜钢铁集团有限公司 | Method for roll skin bead weld repair of 4PG 900*700 four-roll crusher |
| CN103464868A (en) * | 2013-09-11 | 2013-12-25 | 黑龙江宏宇电站设备有限公司 | Technological process for surfacing hot rolled supporting roller |
| CN104002018A (en) * | 2014-06-23 | 2014-08-27 | 上海一钢机电有限公司 | Method for repairing open arc welding and surfacing of continuous casting roller of continuous casting fan-shaped section |
| CN105689848A (en) * | 2014-11-28 | 2016-06-22 | 重庆伊曼环保设备有限公司 | Surfacing repair process for extrusion roll |
| CN105750812A (en) * | 2014-12-15 | 2016-07-13 | 重庆迅升机车配件有限公司 | Converter slab continuous casting roller bead welding repairing technology |
| CN109759772A (en) * | 2019-01-16 | 2019-05-17 | 燕山大学 | A kind of fast repairing method with helicla flute Continuous Casting Rolls |
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| CN111151968A (en) | 2020-05-15 |
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Effective date of registration: 20230920 Address after: Room 2202, 22 / F, Wantong building, No. 3002, Sungang East Road, Sungang street, Luohu District, Shenzhen City, Guangdong Province Patentee after: Shenzhen dragon totem technology achievement transformation Co.,Ltd. Address before: 230000 floor 1, building 2, phase I, e-commerce Park, Jinggang Road, Shushan Economic Development Zone, Hefei City, Anhui Province Patentee before: Dragon totem Technology (Hefei) Co.,Ltd. Effective date of registration: 20230920 Address after: 230000 floor 1, building 2, phase I, e-commerce Park, Jinggang Road, Shushan Economic Development Zone, Hefei City, Anhui Province Patentee after: Dragon totem Technology (Hefei) Co.,Ltd. Address before: 066004 No. 438, Hebei Avenue, seaport District, Hebei, Qinhuangdao Patentee before: Yanshan University |