CN102248281A - Thick plate joint welding method - Google Patents
Thick plate joint welding method Download PDFInfo
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- CN102248281A CN102248281A CN2010101800148A CN201010180014A CN102248281A CN 102248281 A CN102248281 A CN 102248281A CN 2010101800148 A CN2010101800148 A CN 2010101800148A CN 201010180014 A CN201010180014 A CN 201010180014A CN 102248281 A CN102248281 A CN 102248281A
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Abstract
The invention discloses a thick plate joint welding method, which adopts an electroslag welding process to weld two workpieces which are 240 to 286 millimeters thick into a whole and comprises the following: 1, a first step of preparation before welding, which is to prepare a powder material by adding a plurality kinds of iron alloy elements into formula of a pipe coating, prepare the pipe coating by adding adhesive into the powder material after uniformly mixing, coat the pipe coating on the outer walls of pipe poles, fix and mount four pipe poles on a clamping mechanism and regulate the mounting gap between two workpieces; 2, a step of welding, which is to perform electroslag welding by delivering a welding stick into a weld pool formed by the four pipe poles, energize the welding stick and weld the pipe poles, wherein the welding direction is form a lower bevel to an upper bevel; and 3, a step of heat treatment after welding. The thick plate joint welding method has the advantages of high simplicity, convenience and efficiency, high implementability, great improvement on production efficiency and reduction in production cost. When the method is used, the working environment of operators is improved, dust and arc light damage is relieved, and environment is better protected.
Description
Technical field
The present invention relates to a kind of welding method, be specifically related to a kind of welding method of slab banjo fixing butt jointing.
Background technology
Electroslag welding (ESW) is to utilize electric current to pass through resistance heat that the liquid slag produces as thermal source, with workpiece and the upright position welding method of filling the synthetic weld seam of Metal Melting.According to the shape that adopts electrode and whether fixing, electroslag welding can be divided into electroslag welding with wire, electroslag welding with consumable nozzle, electroslag welding with plate electrode.When carrying out big slab electroslag welding welding, generally adopt electroslag welding with consumable nozzle in the industry.
Electroslag welding with consumable nozzle is to be to be fixed on consumable nozzle in the play movement (being formed by steel plate and pipe spot welding) by electrode, and the welding wire of constantly sending in the molten bath constitutes, and adopts the consumable nozzle plate as welding wire guiding, conduction with fill metal.Because electroslag welding with consumable nozzle need customize special consumable nozzle plate according to mother metal to be welded, so cost height and cycle are long, is not suitable for manufacturing big the small lot batch manufacture of weight equipment.Under the situation tight in the production cycle in addition, that quality requirement is high, also be difficult for satisfying production requirement.
Summary of the invention
Technical problem to be solved by this invention provides a kind of welding method of slab banjo fixing butt jointing, and it can be welded as a whole the workpiece that two thickness are 240～286mm.
For solving the problems of the technologies described above, the technical solution of the welding method of slab banjo fixing butt jointing of the present invention is:
The workpiece that the method that adopts electroslag welding with tube electrode is 240～286mm with two thickness is welded as a whole, and may further comprise the steps:
The first step, prepare before the weldering:
A, selection steel pipe: select steel pipe as the pipe utmost point according to the actual conditions of workpiece to be welded;
B, preparation pipe coating: in the pipe formulation for coating material, add multiple alloy elements and obtain powder; Powder mixes the back and adds adhesive, makes pipe coating;
The composition of described pipe formulation for coating material is manganese ore powder 36%, talcum powder 21%, titanium dioxide 8%, dolomite 2%, silica flour 21%, fluorite powder 12%.
The addition of described alloy elements is to add ferrosilicon 150g, molybdenum-iron 150g, ferrotianium 110g, vanadium iron 100g in the per kilogram pipe formulation for coating material.
Described adhesive is sodium silicate: SiO30%, NaO12.5%, S, P≤0.05%.
C, making electrode; To manage coating is coated on the pipe utmost point outer wall;
Described to be coated in the pipe paint thickness that pipe extremely goes up be 2～3mm, after the air dry, the pipe utmost point that scribbles pipe coating cured 2 hours under 250 ℃ of temperature conditions; Prepare aid water-cooled slide block, bakelite plate, bamboo chip;
D, assembling electrode: four pipes extremely fixedly are assemblied on the clamping device, and middle two pipe die openings are 60mm, and the spacing of the pipe utmost point that these two Guan Jiyu outsides are adjacent is 96mm;
E, assemble workpiece to be welded, regulate the fit-up gap of two workpiece, the fit-up gap that makes down groove is 33～35mm, and the fit-up gap of last groove is 35～38mm;
Assemble run-on tab and go out the arc plate;
Regulate clamping device, make four pipe utmost points be in the centre position of the fit-up gap of two workpiece;
F, preheating: parent coal gas heating-up temperature 〉=150 ℃, samming;
Second step, welding:
Carry out electroslag welding, welding wire is sent in four extremely formed molten baths of pipe, the energising welding; Welding direction is for being welded to groove from following groove; Described welding wire is H10Mn2, specification Φ 3.2mm, solder flux HJ431.
Welding parameter in the welding process is: wire feed rate=160～180m/h; Voltage V=46～50V; Speed of welding is 1.2m/h; Pool depth 40～50mm;
The welding stage of drawing is lowered weldingvoltage and wire feed rate gradually;
In the 3rd step, post weld heat treatment: postwelding integral body is advanced stove stress-removal annealing in process.
The method of described post weld heat treatment is: place furnace temperature not to be higher than 300 ℃ stove workpiece, be heated to temperature with the speed of 65 ℃/h of the rate of heat addition and kept 6 hours for 625 ± 20 ℃, be cooled to come out of the stove below 300 ℃ with the speed of 65 ℃/h then and in still air, cool off.
The technique effect that the present invention can reach is:
Compare with traditional electroslag welding with consumable nozzle, electroslag welding with tube electrode of the present invention has following advantage:
1, save the consumable nozzle production process, preparation is simple, quick, is easy to finish different shape, convenient and reliable operation;
2, the pipe utmost point is coated and is had insulating effect, not can with the workpiece short circuit, the fit-up gap can dwindle, and can save welding filling material, improves speed of welding, reduces welding stress;
3, electroslag welding with tube electrode is faster than electroslag welding with consumable nozzle speed of welding, and is with short production cycle;
4, by the coating extremely gone up of pipe alloying in weld seam suitably, improve the weld metal performance, and in conjunction with higher speed of welding, the welding point heat affected area is little, and grain growth is not obvious, and Widmannstatten structure quantity is few, joint impact flexibility is good, postwelding only eliminates stress processing and need not carry out traditional normalizing+temper (electroslag welding with consumable nozzle must carry out normalizing+temper), greatly shortens the production cycle, cuts down the consumption of energy.
Description of drawings
The present invention is further detailed explanation below in conjunction with the drawings and specific embodiments:
Fig. 1 is the fit-up gap schematic diagram of two workpiece;
Fig. 2 is the relative position schematic diagram of four Guan Jiyu workpiece;
Fig. 3 is the process curve figure of post weld heat treatment of the present invention;
Fig. 4 is the flow chart of the welding method of slab banjo fixing butt jointing of the present invention.
The specific embodiment
The welding method of slab banjo fixing butt jointing of the present invention, the method that adopts electroslag welding with tube electrode are that 282mm, length are that the workpiece of 950mm is welded as a whole with two thickness, may further comprise the steps:
The first step, prepare before the weldering:
1, select the steel pipe specification: the actual conditions according to workpiece to be welded are selected suitable steel pipe; The steel pipe specification is external diameter 14mm, 20 steel pipes of wall thickness 4mm;
2, preparation pipe coating;
The composition of pipe formulation for coating material is: manganese ore powder 36%, talcum powder 21%, titanium dioxide 8%, dolomite 2%, silica flour 21%, fluorite powder 12%;
In the pipe formulation for coating material, add multiple alloy elements and obtain powder;
Be crystal grain thinning, the alloy elements addition is in the per kilogram pipe formulation for coating material: ferrosilicon 150g, molybdenum-iron 150g, ferrotianium 110g, vanadium iron 100g; Wherein ferrosilicon is used for deoxidation, improves intensity; Vanadium iron is used for crystal grain thinning, improves impact flexibility;
Powder mixes the back and adds adhesive, makes pipe coating; Adhesive adopts sodium silicate: SiO30%, NaO12.5%, S, P≤0.05%.
3, make electrode;
To manage coating and be evenly coated on the pipe utmost point (the being steel pipe) outer wall, the pipe paint thickness is 2～3mm, after the air dry, the pipe utmost point that scribbles pipe coating is cured 2 hours under 250 ℃ of temperature conditions;
Prepare the needed water-cooled slide block of electroslag welding, bakelite plate, bamboo chip;
4, assembling electrode: extremely fixedly be assemblied in four pipes on the clamping device, centre two pipes die openings are 60mm (centre distances of two pipe utmost points are 60mm promptly), and the spacing of the pipe utmost point that these two Guan Jiyu outsides are adjacent is 96mm (promptly the centre distance of the adjacent pipe utmost point is 96mm outside these two Guan Jiyu);
Distances between middle two pipe utmost points are 60mm, and the distance between the adjacent pipe utmost point in these two Guan Jiyu outsides is 96mm;
These four spacings of managing between the utmost point are to determine that according to the thickness of slab of 282mm this pipe die opening can guarantee good quality of weld joint.If it is improper that the gap is chosen, easily crack or incomplete penetration defect.
5, assembling workpiece 1,2 to be welded, the fit-up gap of two workpiece of adjusting as shown in Figure 1, makes down the about 34mm in fit-up gap of groove, the about 37mm in the fit-up gap of last groove; Be welded to groove (bottom-up formation weld seam) from following groove during welding;
Assemble run-on tab and go out the arc plate;
Regulate clamping device, make four pipe utmost points be in the centre position of the fit-up gap of two workpiece, as shown in Figure 2;
The present invention adopts not reciprocity up and down fit-up gap, solved the weld seam cross-direction shrinkage value different problem of thick plates part along weld bead height, can make the weld width after welding finishes keep climb and fall actinal surface unanimity substantially, thereby can reduce shrinkage stress, avoid cracking.
The present invention has stipulated the upper limit of fit-up gap, increases as the gap, and stress and distortion increase, and the heat affected area increases, and crystal grain is easily thick.
Regulate the bolt up and down of clamping device, make the pipe utmost point be in the center of thickness of workpiece;
6, preheating: parent coal gas heating-up temperature 〉=150 ℃, samming.
Second step, welding:
Selecting for use of welding material: welding wire is selected H10Mn2 for use, specification Φ 3.2mm, solder flux HJ431;
Determining of welding parameter: wire feed rate=160～180m/h; Voltage V=46～50V; Speed of welding is 1.2m/h; Pool depth 40～50mm;
Carry out electroslag welding, welding wire is sent in four extremely formed molten baths of pipe, the energising welding;
Keep substantially invariable welding parameter in the welding process, adjust welding wire, make it to be in the center of fit-up gap; Detect depth of slag bath and leaving water temperature simultaneously;
Use bakelite plate, the bamboo chip stationary pipes utmost point they not to be swung in the welding process in the centre position, gap; Use the water-cooled slide block to quicken the molten bath cooling in the welding process;
Welding is lowered weldingvoltage and wire feed rate in the stage of drawing gradually, cracks and defective such as shrinkage cavity with minimizing;
The 3rd step, after welding treatment:
Remove: electroslag welding is cut off run-on tab and end tab after finishing immediately, can not damage mother metal during cutting;
Check: scrutiny is removed run-on tab and end tab cut surface, weld seam have free of surface defects, removes if defectiveness digs with gas cutting or carbon immediately;
Soldering: at blemish, welding toe and there is the weld defect place of undercut etc. to carry out soldering, manual welding is adopted in soldering, and the welding rod model is J507, and specification is Φ 4.0, welding current I=160～180A, weldingvoltage U=24～27V;
Reconditioning: soldering place weld seam and welding toe reconditioning smooth transition;
Postwelding integral body is advanced stove stress-removal annealing in process; Process curve is as shown in Figure 3 adopted in post weld heat treatment, place furnace temperature not to be higher than 300 ℃ stove workpiece, be heated to temperature with the speed of 65 ℃/hour of the rates of heat addition and kept 6 hours for 625 ± 20 ℃, be cooled to come out of the stove below 300 ℃ with 65 ℃/hour speed then and in still air, cool off.
The present invention has added multiple alloy elements in pipe coating, and controlled grain growth by welding condition, final weld seam has formed comparatively desirable tissue, therefore need not to carry out the heat treatment of normalizing+tempering, only need carry out the annealing in process of stress-removal, through this Technology for Heating Processing, can satisfy the performance requirement of weld seam.
The present invention is simple and effective more, and exploitativeness is higher, can greatly enhance productivity, and reduces production costs.In addition, the present invention can improve operating personnel's working environment, reduces the injury of dust and arc light, environmental protection more.
The present invention can be used for welding the thick forging banjo fixing butt jointing of 282mm of the critical component supporting neck parts in the 300T converter.
Claims (8)
1. the welding method of a slab banjo fixing butt jointing is characterized in that: the workpiece that the method that adopts electroslag welding with tube electrode is 240～286mm with two thickness is welded as a whole, and may further comprise the steps:
The first step, prepare before the weldering:
A, preparation pipe coating: in the pipe formulation for coating material, add multiple alloy elements and obtain powder; Powder mixes the back and adds adhesive, makes pipe coating;
B, making electrode; To manage coating is coated on the pipe utmost point outer wall;
C, assembling electrode: four pipes extremely fixedly are assemblied on the clamping device, and middle two pipe die openings are 60mm, and the spacing of the pipe utmost point that these two Guan Jiyu outsides are adjacent is 96mm;
D, assemble workpiece to be welded, regulate the fit-up gap of two workpiece, the fit-up gap that makes down groove is 33～35mm, and the fit-up gap of last groove is 35～38mm;
Assemble run-on tab and go out the arc plate;
Regulate clamping device, four pipe utmost points are in the fit-up gap of two workpiece;
E, preheating: parent coal gas heating-up temperature 〉=150 ℃, samming;
Second step, welding:
Carry out electroslag welding, welding wire is sent in four extremely formed molten baths of pipe, the energising welding; Welding direction is for being welded to groove from following groove;
Welding parameter in the welding process is: wire feed rate=160～180m/h; Voltage V=46～50V; Speed of welding is 1.2m/h; Pool depth 40～50mm;
The welding stage of drawing is lowered weldingvoltage and wire feed rate gradually;
In the 3rd step, post weld heat treatment: postwelding integral body is advanced stove stress-removal annealing in process.
2. the welding method of slab banjo fixing butt jointing according to claim 1 is characterized in that: the composition of described pipe formulation for coating material is manganese ore powder 36%, talcum powder 21%, titanium dioxide 8%, dolomite 2%, silica flour 21%, fluorite powder 12%.
3. the welding method of slab banjo fixing butt jointing according to claim 1 is characterized in that: the addition of described alloy elements is to add ferrosilicon 150g, molybdenum-iron 150g, ferrotianium 110g, vanadium iron 100g in the per kilogram pipe formulation for coating material.
4. the welding method of slab banjo fixing butt jointing according to claim 1 is characterized in that: described adhesive is sodium silicate: SiO30%, NaO12.5%, S, P≤0.05%.
5. the welding method of slab banjo fixing butt jointing according to claim 1 is characterized in that: described to be coated in the pipe paint thickness that pipe extremely goes up be 2～3mm, after the air dry, the pipe utmost point that scribbles pipe coating cured 2 hours under 250 ℃ of temperature conditions.
6. the welding method of slab banjo fixing butt jointing according to claim 1 is characterized in that: the welding wire in described second step is H10Mn2, specification Φ 3.2mm, solder flux HJ431.
7. the welding method of slab banjo fixing butt jointing according to claim 1, it is characterized in that: the method for the post weld heat treatment in described the 3rd step is: place furnace temperature not to be higher than 300 ℃ stove workpiece, be heated to temperature with the speed of 65 ℃/h of the rate of heat addition and kept 6 hours for 625 ± 20 ℃, be cooled to come out of the stove below 300 ℃ with the speed of 65 ℃/h then and in still air, cool off.
8. the welding method of slab banjo fixing butt jointing according to claim 1 is characterized in that: the pipe in the described first step b step is 20 pipes of Φ 14 * 4 very.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201010180014 CN102248281B (en) | 2010-05-20 | 2010-05-20 | Thick plate joint welding method |
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| CN 201010180014 CN102248281B (en) | 2010-05-20 | 2010-05-20 | Thick plate joint welding method |
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| CN102248281A true CN102248281A (en) | 2011-11-23 |
| CN102248281B CN102248281B (en) | 2013-10-30 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103659184A (en) * | 2013-12-05 | 2014-03-26 | 湖北三江航天红阳机电有限公司 | Method for welding heat dissipation base plates |
| CN103706965A (en) * | 2013-11-29 | 2014-04-09 | 江苏宇杰钢机有限公司 | Protective agent for welding of stainless steel |
| CN105414743A (en) * | 2015-12-17 | 2016-03-23 | 中车洛阳机车有限公司 | Consumable nozzle electroslag overlaying welding repair method for roll |
| TWI549771B (en) * | 2014-04-09 | 2016-09-21 | 中國鋼鐵股份有限公司 | Two-step high-heat-input welding method |
| CN111037930A (en) * | 2019-12-24 | 2020-04-21 | 江苏新宏大集团有限公司 | Hot-melt welding method for plastic cushion block |
| CN115403987A (en) * | 2022-08-19 | 2022-11-29 | 东睦新材料集团股份有限公司 | Lubricating wear-reducing noise-reducing coating and preparation method and application thereof |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103706965A (en) * | 2013-11-29 | 2014-04-09 | 江苏宇杰钢机有限公司 | Protective agent for welding of stainless steel |
| CN103706965B (en) * | 2013-11-29 | 2016-06-08 | 江苏宇杰钢机有限公司 | A kind of stainless steel welding protecting agent |
| CN103659184A (en) * | 2013-12-05 | 2014-03-26 | 湖北三江航天红阳机电有限公司 | Method for welding heat dissipation base plates |
| CN103659184B (en) * | 2013-12-05 | 2016-01-06 | 湖北三江航天红阳机电有限公司 | A kind of welding method of radiating bottom plate |
| TWI549771B (en) * | 2014-04-09 | 2016-09-21 | 中國鋼鐵股份有限公司 | Two-step high-heat-input welding method |
| CN105414743A (en) * | 2015-12-17 | 2016-03-23 | 中车洛阳机车有限公司 | Consumable nozzle electroslag overlaying welding repair method for roll |
| CN111037930A (en) * | 2019-12-24 | 2020-04-21 | 江苏新宏大集团有限公司 | Hot-melt welding method for plastic cushion block |
| CN115403987A (en) * | 2022-08-19 | 2022-11-29 | 东睦新材料集团股份有限公司 | Lubricating wear-reducing noise-reducing coating and preparation method and application thereof |
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| CN102248281B (en) | 2013-10-30 |
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Effective date of registration: 20161201 Address after: 200245 Jiangchuan Road, Shanghai, No. 230, building 1800, No. Patentee after: Shanghai electric heavy milling special equipment Co. Ltd. Patentee after: Shanghai Heavy Machines Plant Co., Ltd. Address before: 200245 Jiangchuan Road, Shanghai, No. 1800, No. Patentee before: Shanghai Heavy Machines Plant Co., Ltd. |