CN110026651A - Double-wire welding method - Google Patents
Double-wire welding method Download PDFInfo
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- CN110026651A CN110026651A CN201910247007.6A CN201910247007A CN110026651A CN 110026651 A CN110026651 A CN 110026651A CN 201910247007 A CN201910247007 A CN 201910247007A CN 110026651 A CN110026651 A CN 110026651A
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Classifications
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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
- B23K9/09—Arrangements or circuits for arc welding with pulsed current or voltage
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D3/00—Diffusion processes for extraction of non-metals; Furnaces therefor
- C21D3/02—Extraction of non-metals
- C21D3/06—Extraction of hydrogen
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Plasma & Fusion (AREA)
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- Crystallography & Structural Chemistry (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Arc Welding In General (AREA)
Abstract
The invention discloses a kind of Double-wire welding methods, belong to welding technology field.Welding method includes: to process welding groove on each workpiece;The welding groove of each workpiece is assembled together;Welding groove is welded using Double Wire Welding, the preceding silk of Double Wire Welding carries out first time welding by the way of impulse welding, to welding groove, and the rear silk of Double Wire Welding is carried out second to welding groove and welded by the way of cold metal transfer weldering;Dehydrogenation is carried out to each workpiece.The present invention can be improved welding efficiency, reduce welding deformation.
Description
Technical field
The invention belongs to welding technology field, in particular to a kind of Double-wire welding method.
Background technique
EQ70 high-strength steel is a kind of steel being widely used on ocean lifting platform, usually in the form of slab into
Row application.It is generally welded using submerged-arc welding between each EQ70 high-strength steel plate.
In the implementation of the present invention, the inventor finds that the existing technology has at least the following problems:
Since submerged-arc welding needs to need to remove welding after welding using granular solder flux, lead to that process is tedious.And
And since the heat input of submerged-arc welding is big, it is easy to produce welding deformation, has adverse effect to welding precision.
Summary of the invention
The embodiment of the invention provides a kind of Double-wire welding methods, and welding efficiency can be improved, reduce welding deformation.It is described
Technical solution is as follows:
The embodiment of the invention provides a kind of Double-wire welding method, the welding method is suitable for EQ70 high-strength steel, described
Welding method includes:
Welding groove is processed on each workpiece;
The welding groove of each workpiece is assembled together;
The welding groove is welded using Double Wire Welding, the preceding silk of the Double Wire Welding is right by the way of impulse welding
The welding groove carries out first time welding, and the rear silk of the Double Wire Welding is by the way of cold metal transfer weldering, to the welding
Groove carries out second and welds;
Dehydrogenation is carried out to each workpiece.
Optionally, the preceding silk is identical with the welding wire of the rear silk, and the mass fraction of carbon is 0.10%, silicon in the welding wire
Mass fraction be 0.40~0.80%, the mass fraction of manganese is 1.30~1.90%, the mass fraction of phosphorus is not more than
0.015%, the mass fraction of vanadium be 0.03%, the mass fraction of sulphur no more than 0.015, the mass fraction of chromium be 0.15%, molybdenum
Mass fraction be 0.25~0.65%, the mass fraction of nickel is 0.80~1.30%.
Optionally, the weldingvoltage of the preceding silk be 27.4V, welding current 389A, wire feed rate 14.7m/min,
Speed of welding is 1.2m/min, dry extension of electrode 18mm.
Optionally, the weldingvoltage of the rear silk is 16.9V, welding current 248A, wire feed rate 8.5m/min, weldering
Connecing speed is 1.2m/min, dry extension of electrode 5mm.
Optionally, the surface roughness Ra of the welding groove is not more than 25.
Optionally, the gap for two welding grooves being assembled together is not more than 2mm, two institutes being assembled together
The maximal clearance of welding groove and the difference of minimum clearance are stated no more than 1mm.
Optionally, before the use Double Wire Welding welds the welding groove, the welding method further include:
The workpiece is preheated;
The workpiece is kept the temperature.
Optionally, the welding method further include:
The preheating temperature of the workpiece is 150~200 DEG C, and the soaking time of the workpiece is 0.5~1h.
Optionally, the welding method further include:
Interlayer temperature between the first time welding and second of welding is not more than 150 DEG C.
It is optionally, described that dehydrogenation is carried out to each workpiece, comprising:
The workpiece is sent into heating furnace with 240~260 DEG C of temperature;
240~260 DEG C are warming up to the rate no more than 50 DEG C/h;
In the heating furnace inside holding 4h;
After the workpiece is cooled to temperature no more than 50 DEG C in the heating furnace, the workpiece is taken out.
Technical solution provided in an embodiment of the present invention has the benefit that
Remove welding groove by processing on each workpiece, and the welding groove of each workpiece be assembled together, with for
The welding of workpiece provides welding basic condition.First time welding is carried out by the impulse welding that preceding silk uses, at welding groove
Molten bath is formd, and has carried out back welding.The cold metal transfer weldering used by rear silk carries out second and welds, with lower temperature
Welding groove is further welded.Since impulse welding and cold metal transfer weldering are not needed using solder flux, and it is cold
The heat input of metal transfer weldering is lower, so welding method provided by the embodiment of the present invention, does not both need to remove solder flux, not yet
Workpiece can be caused to generate welding deformation because of excessively high heat input.
Detailed description of the invention
To describe the technical solutions in the embodiments of the present invention more clearly, make required in being described below to embodiment
Attached drawing is briefly described, it should be apparent that, drawings in the following description are only some embodiments of the invention, for
For those of ordinary skill in the art, without creative efforts, it can also be obtained according to these attached drawings other
Attached drawing.
Fig. 1 is a kind of flow chart of Double-wire welding method provided in an embodiment of the present invention;
Fig. 2 is the flow chart of another Double-wire welding method provided in an embodiment of the present invention.
Specific embodiment
To make the object, technical solutions and advantages of the present invention clearer, below in conjunction with attached drawing to embodiment party of the present invention
Formula is described in further detail.
The embodiment of the invention provides a kind of Double-wire welding method, this method is suitable for EQ70 high-strength steel, as shown in Figure 1,
The welding method includes:
Step 101: processing welding groove on each workpiece.
Step 102: the welding groove of each workpiece is assembled together.
It, can be by the welding slope of two workpiece when needing to weld together two workpiece in above-mentioned implementation
Mouth is docking together, and the welding groove positioning of two workpiece is docking together by way of clamping tooling either spot welding,
Specific positioning method, the application is with no restrictions.
It should be noted that if necessary to welding together more than two workpiece, then likewise, be also required to will be each
The welding groove positioning of a workpiece is docking together, and specific positioning method, the application is with no restrictions.
Step 103: welding groove being welded using Double Wire Welding, the preceding silk of Double Wire Welding is right by the way of impulse welding
Welding groove carries out first time welding, and the rear silk of Double Wire Welding carries out second to welding groove by the way of cold metal transfer weldering
Secondary welding.
, can be by mariages welding machine when realization, so that two tip synchronous marchinges, preceding silk uses a weldering positioned at front
Mouth realizes that weld job, rear silk realize weld job using a tip being located behind, that is to say, that welding for the first time and the
Secondary welding is synchronous to be carried out, and the efficiency of Double Wire Welding can be improved in this way.
Step 104: dehydrogenation is carried out to each workpiece.
Welding groove is removed by processing on each workpiece, and the welding groove of each workpiece is assembled together, for workpiece
Welding provide welding basic condition.First time welding is carried out by the impulse welding that preceding silk uses, is formed at welding groove
Molten bath, and carried out back welding.The cold metal transfer weldering used by rear silk carries out second and welds, with lower temperature butt welding
Groove is connect further to be welded.Since impulse welding and cold metal transfer weldering do not need using solder flux, and cold metal
The heat input of transition weldering is lower, so welding method provided by the embodiment of the present invention, does not both need to remove solder flux, will not be because
Workpiece is caused to generate welding deformation for excessively high heat input.
Fig. 2 is the flow chart of another kind Double-wire welding method provided by the embodiment of the present invention, which is suitable for
EQ70 high-strength steel, in conjunction with Fig. 2, which includes:
Step 201: processing welding groove on each workpiece.
Illustratively, the surface roughness Ra of welding groove is not more than 25.
In above-mentioned implementation, the surface roughness Ra of welding groove is limited in no more than 25, it can be in order to subsequent
Double Wire Welding process, improve the welding precision of Double Wire Welding.
Step 202: the welding groove of each workpiece is assembled together.
Illustratively, the gap for two welding grooves being assembled together is not more than 2mm, two welding being assembled together
The maximal clearance of groove and the difference of minimum clearance are not more than 1mm.
In above-mentioned implementation, the gap for two welding grooves being assembled together is limited no more than 2mm, and assembly
The maximal clearance of two welding grooves together and the difference of minimum clearance are not more than 1mm, can be further convenient for subsequent
Double Wire Welding process, improve the welding precision of Double Wire Welding.
That is, providing good welding base strip by step 201 and step 202 for subsequent Double Wire Welding process
Part.
After the welding groove of each workpiece is assembled together, workpiece is cleaned.
Illustratively, position to be welded and the region around it within the scope of 76mm are cleaned, with Jiang Shui, oil
The impurity such as dirt, iron rust are cleaned out.
Step 203: workpiece is preheated.
In this way, can prevent cold crack, fire check and heat affected area from hardened structure occur, the reliability of welding is improved.
Illustratively, the preheating temperature of workpiece can be 150~200 DEG C.
Step 204: workpiece is kept the temperature.
In this way, workpiece can be made full and uniform heated, to guarantee the effect of preheating.
Illustratively, the soaking time of workpiece is 0.5~1h.
Optionally, it on the basis of the thickness of workpiece has reached 25mm, as the every increase 25mm of the thickness of workpiece, then needs
It is further added by soaking time 1h, to ensure that being fully warmed-up for workpiece.
Step 205: welding groove being welded using Double Wire Welding, the preceding silk of Double Wire Welding is right by the way of impulse welding
Welding groove carries out first time welding, and the rear silk of Double Wire Welding carries out second to welding groove by the way of cold metal transfer weldering
Secondary welding.
Welding manner can be identical with step 103, and this will not be repeated here.
Illustratively, preceding silk is identical with the welding wire of rear silk, and the mass fraction of carbon is the mass fraction of 0.10%, silicon in welding wire
Mass fraction for 0.40~0.80%, manganese is 1.30~1.90%, the mass fraction of phosphorus is not more than the quality of 0.015%, vanadium
Score is 0.03%, the mass fraction of sulphur no more than the mass fraction of 0.015, chromium is 0.15%, the mass fraction of molybdenum is 0.25
~0.65%, the mass fraction of nickel is 0.80~1.30%.
In above-mentioned implementation, each element mass fraction of welding wire, can be very good be suitable for EQ70 high-strength steel into
Row welding, especially meets the welding requirements to EQ70 high-strength steel.
Illustratively, the weldingvoltage of preceding silk is 27.4V, welding current 389A, wire feed rate 14.7m/min, weldering
Connecing speed is 1.2m/min, dry extension of electrode 18mm.
Illustratively, the weldingvoltage of rear silk is 16.9V, welding current 248A, wire feed rate 8.5m/min, welding
Speed is 1.2m/min, dry extension of electrode 5mm.
In above-mentioned implementation, the setting of the welding parameter of preceding silk and rear silk can be very good to be suitable for EQ70 high
Strong steel is welded, and the welding requirements to EQ70 high-strength steel is especially met.
Optionally, the interlayer temperature between welding for the first time and second of welding is not more than 150 DEG C.
It should be noted that if the interlayer temperature between welding for the first time and second of welding does not meet above-mentioned requirements,
It then needs to re-execute the steps 203 and step 204, i.e., workpiece is preheated and kept the temperature again.
Step 206: dehydrogenation is carried out to each workpiece.
It can be realized by following steps:
Firstly, workpiece is sent into heating furnace with 240~260 DEG C of temperature.
Then, 240~260 DEG C are warming up to the rate no more than 50 DEG C/h.
Then, 4h is kept the temperature in heating furnace.
It should be noted that in the thickness of workpiece on the basis of 100mm, as the every increase 25mm of workpiece, soaking time
Increase 1h.
Finally, taking out workpiece after workpiece is cooled to temperature no more than 50 DEG C in heating furnace.
Welding groove is removed by processing on each workpiece, and the welding groove of each workpiece is assembled together, for workpiece
Welding provide welding basic condition.First time welding is carried out by the impulse welding that preceding silk uses, is formed at welding groove
Molten bath, and carried out back welding.The cold metal transfer weldering used by rear silk carries out second and welds, with lower temperature butt welding
Groove is connect further to be welded.Since impulse welding and cold metal transfer weldering do not need using solder flux, and cold metal
The heat input of transition weldering is lower, so welding method provided by the embodiment of the present invention, does not both need to remove solder flux, will not be because
Workpiece is caused to generate welding deformation for excessively high heat input.
The foregoing is merely presently preferred embodiments of the present invention, is not intended to limit the invention, it is all in spirit of the invention and
Within principle, any modification, equivalent replacement, improvement and so on be should all be included in the protection scope of the present invention.
Claims (10)
1. a kind of Double-wire welding method, which is characterized in that the welding method is suitable for EQ70 high-strength steel, the welding method packet
It includes:
Welding groove is processed on each workpiece;
The welding groove of each workpiece is assembled together;
The welding groove is welded using Double Wire Welding, the preceding silk of the Double Wire Welding is by the way of impulse welding, to described
Welding groove carries out first time welding, and the rear silk of the Double Wire Welding is by the way of cold metal transfer weldering, to the welding groove
Second is carried out to weld;
Dehydrogenation is carried out to each workpiece.
2. Double-wire welding method according to claim 1, which is characterized in that the welding wire phase of the preceding silk and the rear silk
Together, the mass fraction of carbon is 0.10% in the welding wire, the mass fraction of silicon is 0.40~0.80%, the mass fraction of manganese is
1.30~1.90%, the mass fraction of phosphorus is that the 0.03%, mass fraction of sulphur is little no more than the mass fraction of 0.015%, vanadium
In the mass fraction of 0.015, chromium is 0.15%, the mass fraction of molybdenum is 0.25~0.65%, the mass fraction of nickel be 0.80~
1.30%.
3. Double-wire welding method according to claim 1, which is characterized in that the weldingvoltage of the preceding silk is 27.4V, weldering
Connecing electric current is 389A, wire feed rate 14.7m/min, speed of welding 1.2m/min, dry extension of electrode 18mm.
4. Double-wire welding method according to claim 1, which is characterized in that the weldingvoltage of silk is 16.9V, weldering after described
Connecing electric current is 248A, wire feed rate 8.5m/min, speed of welding 1.2m/min, dry extension of electrode 5mm.
5. Double-wire welding method according to claim 1, which is characterized in that the surface roughness Ra of the welding groove is not
Greater than 25.
6. Double-wire welding method according to claim 1, which is characterized in that two welding grooves being assembled together
Gap be not more than 2mm, the maximal clearance of two welding grooves and the difference of minimum clearance being assembled together are not more than
1mm。
7. Double-wire welding method according to claim 1, which is characterized in that use Double Wire Welding to the welding slope described
Before mouth is welded, the welding method further include:
The workpiece is preheated;
The workpiece is kept the temperature.
8. Double-wire welding method according to claim 7, which is characterized in that the welding method further include:
The preheating temperature of the workpiece is 150~200 DEG C, and the soaking time of the workpiece is 0.5~1h.
9. Double-wire welding method according to claim 8, which is characterized in that the welding method further include:
Interlayer temperature between the first time welding and second of welding is not more than 150 DEG C.
10. Double-wire welding method according to claim 8, which is characterized in that described disappear at hydrogen to each workpiece
Reason, comprising:
The workpiece is sent into heating furnace with 240~260 DEG C of temperature;
240~260 DEG C are warming up to the rate no more than 50 DEG C/h;
In the heating furnace inside holding 4h;
After the workpiece is cooled to temperature no more than 50 DEG C in the heating furnace, the workpiece is taken out.
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CN201910247007.6A CN110026651A (en) | 2019-03-29 | 2019-03-29 | Double-wire welding method |
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Cited By (1)
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CN114850728A (en) * | 2022-05-23 | 2022-08-05 | 钢铁研究总院有限公司 | Welding wire suitable for 7A52 high-strength aluminum alloy and welding method |
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Application publication date: 20190719 |