CN112958886B - High-efficiency assembly welding method for thick-specification composite blank - Google Patents
High-efficiency assembly welding method for thick-specification composite blank Download PDFInfo
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- CN112958886B CN112958886B CN202110176120.7A CN202110176120A CN112958886B CN 112958886 B CN112958886 B CN 112958886B CN 202110176120 A CN202110176120 A CN 202110176120A CN 112958886 B CN112958886 B CN 112958886B
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- 238000003466 welding Methods 0.000 title claims abstract description 119
- 239000002131 composite material Substances 0.000 title claims abstract description 45
- 238000000034 method Methods 0.000 title claims abstract description 27
- 239000000463 material Substances 0.000 claims abstract description 74
- 239000000758 substrate Substances 0.000 claims abstract description 23
- 239000003795 chemical substances by application Substances 0.000 claims description 14
- 239000011248 coating agent Substances 0.000 claims description 4
- 238000000576 coating method Methods 0.000 claims description 4
- 239000011324 bead Substances 0.000 claims description 3
- 238000005253 cladding Methods 0.000 claims description 3
- 238000009434 installation Methods 0.000 claims description 3
- JEIPFZHSYJVQDO-UHFFFAOYSA-N iron(III) oxide Inorganic materials O=[Fe]O[Fe]=O JEIPFZHSYJVQDO-UHFFFAOYSA-N 0.000 claims description 3
- 230000003746 surface roughness Effects 0.000 claims description 3
- 239000002184 metal Substances 0.000 abstract description 8
- 229910052751 metal Inorganic materials 0.000 abstract description 8
- 238000005192 partition Methods 0.000 abstract description 7
- 238000004519 manufacturing process Methods 0.000 description 6
- 238000010894 electron beam technology Methods 0.000 description 4
- 238000005096 rolling process Methods 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 2
- 125000006850 spacer group Chemical group 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 239000010953 base metal Substances 0.000 description 1
- 238000010923 batch production Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000010891 electric arc Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/18—Submerged-arc welding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/235—Preliminary treatment
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/32—Accessories
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Mechanical Engineering (AREA)
- Arc Welding In General (AREA)
Abstract
The invention relates to a high-efficiency assembly welding method for thick-specification composite blanks, which comprises the following steps of: the length and width of the base material are 40-100mm longer than the length and width of the covering material respectively; placing a lower substrate of the composite blank on a bottom layer, and sequentially placing two covering materials; installing the frame in a groove formed by the substrate and the covering material, wherein the bottom edge of the frame is arranged at the bottom of the groove and is symmetrical left and right; the frame divides the groove into two small grooves; and sequentially welding the two grooves by using submerged arc welding. The advantages are that: the time for assembling and welding is effectively reduced, and the working efficiency of assembling and welding the composite board is improved. According to the method for assembling and welding, the assembling efficiency is improved by at least 50 percent, and the assembling efficiency can be improved by more than 1 time for large thick plates. In addition, because the frame can play the role of a partition plate, the situation that the molten metal flows into the separant is not needed, the partition plate is not needed to be installed, the partition plate working procedure can be eliminated, and the yield is improved.
Description
Technical Field
The invention belongs to the field of composite blank welding, and particularly relates to a high-efficiency assembly welding method for thick-specification heterogeneous composite blanks with the thickness of more than 250 mm.
Background
By adopting the rolling method compounding technology, metals with large differences of chemical components, strength, melting point and thermal expansion coefficient can be metallurgically combined to form the metal laminated composite plate, so that the metal laminated composite plate has the bearing capacity of base metal and special service performances of corrosion resistance, oxidation resistance and the like of coating metal, and the cost of the material is reduced. In the production of composite panels, assembly is an important step. The four types of base materials and the clad materials are welded together in a welding mode to form an integral blank, so that the composite plate is finally produced through rolling. The assembly of the prior heterogeneous composite plate mainly comprises two forms of vacuum electron beam assembly and electric arc welding assembly. The vacuum electron beam assembly has the characteristics of large weld fusion width ratio, high welding speed and the like. However, the one-time investment of the vacuum electron beam welding machine is too large, which limits the application of the method. Meanwhile, vacuum electron beam welding is easily influenced by various factors such as a magnetic field and the like, and the welding quality is unstable. Therefore, conventional arc welding is still the most common welding method in heterogeneous composite plate assemblies.
In the currently commonly used production process of symmetrical composite boards, the size of the base material is larger than that of the clad material, and a groove is formed between the base material and the clad material. The periphery of the groove is filled with arc welding to form a welding seam. To prevent the weld metal from flowing into the gap between the two clad sheets, a spacer sheet of about 12-20mm thickness is typically pre-welded to the clad sheet surface. The depth of the weld is equal to the difference in the dimensions of the base and clad material minus the thickness of the spacer, and the width of the weld is equal to the thickness of the two clad materials, see figure 1.
Because the welding seam bears a large shearing force in the rolling process, the welding seam should ensure enough bearing capacity in order to ensure the smooth completion of the rolling process. The load-bearing capacity of the weld depends on the depth of the weld and is independent of the width of the weld. The weld width is closely related to the total fill of the weld. When the target finished composite board specification is higher, the corresponding clad material blank specification also needs to be correspondingly improved. The width of the welding seam often reaches more than 60mm, even 80-100mm, which causes extremely large welding workload. When the assembly process of a pair of composite plates is completed, the continuous welding time is 30-40 hours, and meanwhile, the continuous welding operation deteriorates the welding conditions. In addition, because the separator needs to be welded on the cladding metal, the base material must be reserved with larger size, which also affects the yield of the final composite board and increases the manufacturing cost. The low welding efficiency of the thick-specification composite board produced by the prior art becomes the bottleneck of the whole composite board production.
Disclosure of Invention
In order to overcome the defects of the prior art, the invention aims to provide a high-efficiency assembly welding method for thick composite blanks, which improves the assembly efficiency of composite plates, reduces the manufacturing cost of the composite plates and meets the batch production requirement of heterogeneous composite steel plates on the premise that the composite blanks with the thickness of more than 250mm meet the quality of the composite plates.
In order to achieve the purpose, the invention is realized by the following technical scheme:
a high-efficiency assembly welding method for thick-specification composite blanks comprises the following steps:
1) preparing a blank: the length and the width of the base material are 40-100mm longer than those of the clad material respectively;
2) surface processing: processing the surfaces to be contacted of the base material and the clad material, and removing oil, rust and an oxide layer on the surfaces to be contacted; the surface roughness Ra is less than 6 mu m;
3) coating a release agent after the clad material is processed, and placing the coated release agent in dry air to dry for more than or equal to 12 hours;
4) frame processing: the cross section of the frame is an isosceles trapezoid, the height of the trapezoid is half of the length difference between the base material and the composite material, the thickness of the two clad materials is subtracted by 8-16mm from the bottom edge of the trapezoid, and the included angle between the side edge of the trapezoid and the vertical line is 30-50 degrees; 4 frames are processed on the pair of composite blanks, wherein the lengths of two frames are equal to the length of the base material, and the lengths of the other two frames are equal to the width of the composite material;
5) assembling: placing a lower substrate of the composite blank on a bottom layer, and sequentially placing two covering materials; the side of the clad material coated with the release agent is opposite, the release agent is clamped in the middle, and finally the clad material is placed on the composite blank substrate; the processing surfaces of the substrate and the clad material are opposite to each other in pairs, the clad material is ensured to be in the middle of the substrate in the placing process, and the substrate on each side is 20-50mm longer than the clad material;
6) and (3) blank spot fixing: welding the joint of the base material and the covering material by gas shielded welding;
7) hoisting: after the tack welding is finished, hoisting the blank vertically by using hoisting equipment to enable a welding line to be welded to be placed in a flat welding position;
8) frame installation: installing the frame in a groove formed by the substrate and the covering material, wherein the bottom edge of the frame is arranged at the bottom of the groove and is symmetrical left and right; the top edge of the trapezoid of the frame is flush with the substrate, the bottom edge of the frame and the covering material are fixedly connected by gas shielded welding after the frame is placed, the length of each fixing welding line is 50-100mm, and the distance is 200-250 mm; after the point fixing, the frame divides the groove into two small grooves;
9) sequentially welding two grooves by using submerged-arc welding;
10) firstly welding a welding seam to be welded at a flat welding position, then welding a welding seam at the opposite side, a welding seam at the side, and finally welding a welding seam at the opposite side of the welding seam at the side;
11) and (5) checking the welding quality, and finishing the assembly welding.
The welding current of the submerged arc welding of the step 9) is 500-650A, the voltage is 28-33V, and the welding speed is 28-35 cm/min.
And 9) after the two grooves are welded to be flat, the surface of the groove is covered by the uppermost welding bead integrally.
The thickness of the separant in the step 3) is 0.5-1 mm.
Step 10), after welding of a welding seam to be welded at the flat welding position is finished, turning over the blank by 180 degrees, and repeating the step 8) to the step 9) to weld a symmetrical plane; turning the blank by 90 degrees, and repeating the steps 8) to 9), and welding the other side face; finally, the workpiece is turned over by 180 degrees, and the last side is welded.
Compared with the prior art, the invention has the beneficial effects that:
according to the high-efficiency assembly welding method for the thick-specification heterogeneous composite blanks, the assembly welding time is effectively shortened and the operation efficiency of the assembly welding of the composite boards is improved by optimizing the welding method. According to the method for assembling and welding, the assembling efficiency is improved by at least 50 percent, and the assembling efficiency can be improved by more than 1 time for large thick plates. In addition, because the frame can play the role of a partition plate, the situation that the molten metal flows into the separant is not needed, the partition plate is not needed to be installed, the partition plate working procedure can be eliminated, and the yield is improved.
Drawings
Fig. 1 is a schematic view of an original welding structure of a symmetrical composite plate.
FIG. 2 is a schematic diagram of a high-efficiency assembly welding structure of a thick-gauge heterogeneous composite blank.
In the figure: 1-base material 2-clad material 3-partition plate 4-welding seam 5-frame.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings, but it should be noted that the present invention is not limited to the following embodiments.
Example (b):
referring to fig. 2, a high-efficiency assembly welding method for thick-gauge composite blanks comprises the following steps:
1) preparing a blank: the length and the width of the base material are respectively 50mm longer than those of the clad material;
2) surface processing: processing the surfaces to be contacted of the base material and the clad material, and removing oil, rust and an oxide layer on the surfaces to be contacted; the surface roughness Ra is less than 6 mu m;
3) coating a release agent after the clad material is processed, wherein the thickness of the release agent is 0.5-1mm, and the release agent is coated and then placed in dry air to be dried for more than or equal to 12 hours;
4) frame processing: the cross section of the frame is an isosceles trapezoid, the height of the trapezoid is 30mm, the bottom edge of the trapezoid is the sum of the thicknesses of the two clad materials minus 10mm, the included angle between the side edge of the trapezoid and a vertical line is 40 degrees, and the length of the frame is equal to the length and the width of the base material;
5) assembling: placing a lower substrate of the composite blank on a bottom layer, and sequentially placing two covering materials; the side of the clad material coated with the release agent is opposite, the release agent is clamped in the middle, and finally the clad material is placed on the composite blank substrate; the processing surfaces of the substrate and the clad material are opposite to each other in pairs, the clad material is ensured to be in the middle of the substrate in the placing process, and the substrate on each side is 25mm longer than the clad material;
6) and (3) blank spot fixing: welding the joint of the base material and the covering material by gas shielded welding, wherein 8 fillet welds at the periphery are firmly welded;
7) hoisting: after the tack welding is finished, hoisting the blank vertically by using hoisting equipment to enable a welding line to be welded to be placed in a flat welding position;
8) frame installation: installing the frame in a groove formed by the substrate and the covering material, wherein the bottom edge of the frame is arranged at the bottom of the groove and is symmetrical left and right; the top edge of the trapezoid of the frame is flush with the substrate, the bottom edge of the frame and the covering material are fixedly connected through gas shielded welding after the frame is placed, the length of each fixedly connected welding line is 60mm, and the distance between the fixedly connected welding lines is 200 mm; after the point fixing, the frame divides the groove into two small grooves;
9) sequentially welding two grooves by using submerged arc welding, wherein the current is 500-650A, the voltage is 28-33V, and the welding speed is 28-35 cm/min; after the two grooves are welded flat, the uppermost welding bead covers the surface of the groove integrally;
10) after one side is welded, turning the blank by 180 degrees, and repeating the steps 8) to 9) to weld the symmetrical plane; turning the blank by 90 degrees, and repeating the steps 8) to 9), and welding the other side face; finally, turning 180 degrees, and welding the last side;
11) and (5) checking the welding quality, and finishing the assembly welding.
The embodiment is as follows:
the examples and comparative examples in the table above are in one-to-one correspondence. It can be seen that the method of the present invention has insensitive welding material consumption and man-hour consumption to plate thickness, and the results are close to each other in each plate thickness condition, and the main factor is the length and width of the blank. The traditional process has a very large relationship with the thickness of the plate, and the consumption of welding materials and working hours obviously increases along with the increase of the thickness of the plate. The results of the above examples and comparative processes show that the use of the present invention is more conducive to reducing the assembly cost and improving the welding production efficiency.
Claims (4)
1. A high-efficiency assembly welding method for thick-specification composite blanks is characterized by comprising the following steps:
1) preparing a blank: the length and the width of the base material are 40-100mm longer than those of the clad material respectively;
2) surface processing: processing the surfaces to be contacted of the base material and the clad material, and removing oil, rust and an oxide layer on the surfaces to be contacted; the surface roughness Ra is less than 6 mu m;
3) coating a release agent after the clad material is processed, and placing the coated release agent in dry air to be dried for more than or equal to 12 hours;
4) frame processing: the cross section of the frame is an isosceles trapezoid, the height of the trapezoid is half of the length difference between the base material and the cladding material, the thickness of the two cladding materials is subtracted by 8-16mm from the lower bottom edge of the trapezoid, and the included angle between the side edge of the trapezoid and the vertical line is 30-50 degrees; 4 frames are processed on the pair of composite blanks, wherein the lengths of two frames are equal to the length of the base material, and the lengths of the other two frames are equal to the width of the clad material;
5) assembling: placing a lower substrate of the composite blank on a bottom layer, and sequentially placing two covering materials; the side of the clad material coated with the release agent is opposite, the release agent is clamped in the middle, and finally the clad material is placed on the composite blank substrate; the processing surfaces of the substrate and the clad material are opposite to each other in pairs, the clad material is ensured to be in the middle of the substrate in the placing process, and the substrate on each side is 20-50mm longer than the clad material;
6) and (3) blank spot fixing: welding the joint of the base material and the covering material by gas shielded welding;
7) hoisting: after the tack welding is finished, hoisting the blank vertically by using hoisting equipment to enable a welding line to be welded to be placed in a flat welding position;
8) frame installation: installing the frame in a groove formed by the substrate and the covering material, wherein the bottom edge of the frame is arranged at the bottom of the groove and is symmetrical left and right; the top edge of the trapezoid of the frame is flush with the substrate, the bottom edge of the frame and the covering material are fixedly connected by gas shielded welding after the frame is placed, the length of each fixing welding line is 50-100mm, and the distance is 200-250 mm; after the point fixing, the frame divides the groove into two small grooves;
9) sequentially welding two grooves by using submerged-arc welding;
10) firstly welding a welding seam to be welded at a flat welding position, then welding a welding seam at the opposite side, a welding seam at the side, and finally welding a welding seam at the opposite side of the welding seam at the side;
after welding of the welding seam to be welded at the flat welding position is finished, turning the blank by 180 degrees, and repeating the steps 8) -9) to weld the symmetrical surface; turning the blank by 90 degrees, and repeating the steps 8) to 9), and welding the other side face; finally, turning 180 degrees, and welding the last side;
11) and (5) checking the welding quality, and finishing the assembly welding.
2. The high-efficiency assembly welding method for the thick-specification composite blank as claimed in claim 1, wherein the welding current of the submerged arc welding in the step 9) is 500-650A, the voltage is 28-33V, and the welding speed is 28-35 cm/min.
3. The high-efficiency assembly welding method for thick-gauge composite blanks according to claim 1, wherein after the two grooves are welded in the step 9), the uppermost welding bead covers the surfaces of the grooves integrally.
4. The high-efficiency assembly welding method for thick-gauge composite blanks according to claim 1, wherein the thickness of the release agent in the step 3) is 0.5-1 mm.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6393410A (en) * | 1986-10-07 | 1988-04-23 | Nippon Steel Corp | High efficiency slab assembly method |
| JPH07241685A (en) * | 1994-03-04 | 1995-09-19 | Nkk Corp | Manufacture of clad steel plate |
| CN103639203A (en) * | 2013-11-10 | 2014-03-19 | 中国第一重型机械股份公司 | Vacuum packaging method for symmetric hot rolling manufactured stainless steel clad plates |
| CN107717332A (en) * | 2017-06-26 | 2018-02-23 | 太原科技大学 | A kind of manufacture method of easily welding bound edge stainless steel clad plate |
| CN108246825A (en) * | 2017-12-25 | 2018-07-06 | 南京钢铁股份有限公司 | A kind of preparation method of TMCP types duplex stainless steel clad plate peculiar to vessel |
| CN111299974A (en) * | 2020-03-13 | 2020-06-19 | 科斯焊接技术(无锡)有限公司 | Symmetric hot-rolled composite plate blank and seal welding method thereof |
-
2021
- 2021-02-09 CN CN202110176120.7A patent/CN112958886B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6393410A (en) * | 1986-10-07 | 1988-04-23 | Nippon Steel Corp | High efficiency slab assembly method |
| JPH07241685A (en) * | 1994-03-04 | 1995-09-19 | Nkk Corp | Manufacture of clad steel plate |
| CN103639203A (en) * | 2013-11-10 | 2014-03-19 | 中国第一重型机械股份公司 | Vacuum packaging method for symmetric hot rolling manufactured stainless steel clad plates |
| CN107717332A (en) * | 2017-06-26 | 2018-02-23 | 太原科技大学 | A kind of manufacture method of easily welding bound edge stainless steel clad plate |
| CN108246825A (en) * | 2017-12-25 | 2018-07-06 | 南京钢铁股份有限公司 | A kind of preparation method of TMCP types duplex stainless steel clad plate peculiar to vessel |
| CN111299974A (en) * | 2020-03-13 | 2020-06-19 | 科斯焊接技术(无锡)有限公司 | Symmetric hot-rolled composite plate blank and seal welding method thereof |
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