CN105939812A

CN105939812A - One-side submerged arc welding method for multielectrode and method for producing welded product

Info

Publication number: CN105939812A
Application number: CN201480074393.9A
Authority: CN
Inventors: 铃木励; 铃木励一; 山崎圭; 幸村正晴; 村西良昌
Original assignee: Kobe Steel Ltd
Current assignee: Kobe Steel Ltd
Priority date: 2014-02-12
Filing date: 2014-10-03
Publication date: 2016-09-14
Anticipated expiration: 2034-10-03
Also published as: JP6211431B2; KR20160105901A; WO2015122046A1; JP2015150571A; CN105939812B; KR102034475B1

Abstract

A welding device (1) performs one-side submerged arc welding of a steel plate by using a first welding unit (10) which uses a first wire (110), a second welding unit (20) which uses a second wire (120), a third welding unit (30) which uses a third wire (130), and a fourth welding unit (40) which uses a fourth wire (140). When doing so, the first welding unit (10) controls the feeding speed of the first wire (110) so as to be a constant speed by using a first feeding device (11), and supplies power to the first wire (110) by using a first welding power source (12) for which the power-supply method is set to AC and the external properties are set to a constant voltage. As a result, it is possible to reduce faults in the appearance of a penetration bead obtained by the one-side submerged arc welding of a multielectrode.

Description

Multi-electrode one side submerged-arc welding method, the manufacture method of welding thing

Technical field

The present invention relates to a kind of multi-electrode one side submerged-arc welding method, the manufacture method of welding thing.

Background technology

One as self-consuming electrode type arc-welding process, it is known that following submerged arc welding method: by by the metal of powdery, artificial The solder flux that oxide or mineral etc. are constituted is dispersed in the surface of the groove being arranged at steel plate, and is being piled up in the groove of steel plate The electrode wire in solder flux carried out supply is passed through electric current and produces electric arc from electrode wire, thus electrode wire and steel plate is melted Mixing and integrated.With gas metal arc welding method, TIG welding method, gas shielded arc welding Other arc-welding process such as method are compared, and this submerged arc welding method makes penetration deepen by using big electric current, has high-duty advantage.

Here, recorded a kind of submerged arc welding method in patent documentation 1, its use has the droop characteristic as external behavior Or electrode wire is powered by the source of welding current of constant current characteristic, and weldingvoltage is utilized to set signal and weldingvoltage The size of the signal of the difference of feedback signal controls electrode wire feed speed.

It addition, recorded a kind of multi-electrode one side submerged arc welding method in quoting document 2, it configures multiple side by side along groove Electrode wire, and steel plate rear side configure gasket material, thus use multiple electrode wire by walking 1 time in the way of pair Weld to rear side from the face side of steel plate.This multi-electrode one side submerged arc welding method due to can by the full depth of steel plate with Walk 1 time (calling it as once running (one run)) completely welding procedure and without overturning steel plate, therefore applied flexibly widely In the field such as shipbuilding, bridge.

Prior art literature

Patent documentation

Patent documentation 1: Japanese Unexamined Patent Publication 2000-117442 publication

Patent documentation 2: Japanese Unexamined Patent Publication 2007-268551 publication

Summary of the invention

The problem that invention is to be solved

For above-mentioned multi-electrode one side submerged-arc welding, in multiple electrode wire, steel plate is carried out by main utilization at first The electrode wire (leading electrode) of welding forms root pass in the rear side of steel plate.

But, there is the welding electricity of droop characteristic or constant current characteristic using the electrode wire to leading electrode to use In the case of source is powered and controls the composition of feed speed based on executed arc voltage feedback, the root at gained welds sometimes Road produces bad order.

It is an object of the invention to reduce the bad order of the root pass obtained by multi-electrode one side submerged-arc welding.

For solving the means of problem

The present invention is a kind of multi-electrode one side submerged-arc welding method, it is characterised in that it is the use of leading electrode and continues this The multi-electrode one side submerged-arc welding method of the rear row electrode of leading electrode, makes in above-mentioned leading electrode and above-mentioned rear row electrode respectively With the welding wire of a diameter of more than 2.4mm, power supply mode and external behavior to the power supply that each welding wire is powered are welded with each The speed control method of feed speed of silk is as follows: be set in above-mentioned leading electrode above-mentioned power supply mode be exchange, above-mentioned External behavior be constant voltage characteristic, above-mentioned speed control method be constant speed control, above-mentioned rear row electrode setting become with Under any one, i.e.

(a) above-mentioned power supply mode be direct current, said external characteristic be constant voltage characteristic, above-mentioned speed control method be perseverance Determine speed controlling,

B () above-mentioned power supply mode is exchange, said external characteristic is constant voltage characteristic, above-mentioned speed control method is perseverance Determine speed controlling,

C () above-mentioned power supply mode is exchange, said external characteristic is constant current characteristic, above-mentioned speed control method is base Voltage Feedback in arc voltage controls,

D () above-mentioned power supply mode is exchange, said external characteristic is droop characteristic, above-mentioned speed control method is based on electricity The Voltage Feedback of arc voltage controls, and

(e) above-mentioned power supply mode be direct current, said external characteristic be constant current characteristic, above-mentioned speed control method be base Voltage Feedback in arc voltage controls.

For this kind of multi-electrode one side submerged-arc welding method, it is characterised in that above-mentioned rear row electrode package containing continue above-mentioned in advance Multiple electrodes of electrode and constitute, in the above-mentioned multiple electrodes constituting above-mentioned rear row electrode respectively by above-mentioned power supply mode, on State external behavior and above-mentioned speed control method is set as any one in above-mentioned (a)～above-mentioned (e).

Furthermore it is possible to be following feature: in the above-mentioned multiple electrodes constituting above-mentioned rear row electrode, from above-mentioned leading electrode From the point of view of be positioned on above-mentioned power supply mode, said external characteristic and above-mentioned speed control method be set as by the final electrode of rear side State (c) or above-mentioned (d).

And then, can be following feature: in the case of using the above-mentioned power supply with above-mentioned constant voltage characteristic, in work The slope i.e. differential value dV/dI of the voltage versus current making point is-12.0 × 10^-3(V/A) more than.

Furthermore, it is possible to for following feature: using the above-mentioned electricity with above-mentioned constant current characteristic or above-mentioned droop characteristic In the case of source, the slope of the voltage versus current in operating point i.e. differential value dV/dI is-24.0 × 10^-3(V/A) below.

If it addition, from other viewpoints, then the present invention is a kind of manufacture method welding thing, it is characterised in that it is By employing leading electrode and the weldering that mother metal is welded by the one side submerged-arc welding of row electrode after this leading electrode Connect the manufacture method of thing, above-mentioned leading electrode and above-mentioned rear row electrode use the welding wire of a diameter of more than 2.4mm respectively, right The speed control method of the feed speed of the power supply mode of the power supply that each welding wire is powered and external behavior and each welding wire As follows: be set in above-mentioned leading electrode above-mentioned power supply mode be exchange, said external characteristic be constant voltage characteristic, above-mentioned Speed control method is constant speed control, is set to following any one, i.e. in above-mentioned rear row electrode

Invention effect

According to the present invention it is possible to reduce the bad order of the root pass obtained by multi-electrode one side submerged-arc welding.

Accompanying drawing explanation

Fig. 1 is the figure of the schematic configuration of the welder representing embodiments of the present invention.

Fig. 2 is for the first welding unit～each source of welding current of the 4th welding unit and the composition of feedway are described Figure.

(a)～(c) of Fig. 3 is the figure of the external behavior for the source of welding current is described.

Fig. 4 is the figure of the composition of the experimental provision for first embodiment and the first comparative example are described.

Fig. 5 is the figure of the composition of the experimental provision for the second embodiment and the second comparative example are described.

Fig. 6 is the figure of the composition of the experimental provision for the 3rd embodiment and the 3rd comparative example are described.

(a) of Fig. 7 is for for illustrating first embodiment and each steel plate of the first comparative example and the figure of size of groove, (b) For for illustrating that the second embodiment and each steel plate of the second comparative example and the figure of size of groove, (c) are for for illustrating that the 3rd is real Execute the figure of the size of example and each steel plate of the 3rd comparative example and groove.

Detailed description of the invention

Hereinafter, with reference to apposition accompanying drawing, embodiments of the present invention are described in detail.

Fig. 1 is the figure of the schematic configuration of the welder 1 representing present embodiment.This welder 1 is for using 4 electrodes (welding wire) carries out the device of one side submerged-arc welding (4 electrode one side submerged-arc welding) to the workpiece (not shown) comprising steel plate.

Welder 1 possess use the first welding wire 110 to carry out welding the first welding unit 10, use the second welding wire 120 Carry out the second welding unit 20 welded, the 3rd welding unit 30 using the 3rd welding wire 130 to carry out welding and use the 4th weldering Silk 140 carries out the 4th welding unit 40 welded.It addition, welder 1 possesses: carry the first welding unit 10～the 4th welding Unit 40 and drive dress along the chassis 90 that moving direction A to the left runs from right side in figure, the chassis that drives chassis 90 Put 50 and control the control device 60 of action of the first welding unit 10～the 4th welding unit 40 and chassis driving means 50. And then, welder 1 possesses internal collecting table solder flux (not shown) and towards the first weldering of lower section supply schedule solder flux in figure Agent feeding device 70 and the second welding flux feeding device 80.It is explained, in this embodiment, controls device the 60, first solder flux supply dress Put 70 and second welding flux feeding device 80 be all mounted on chassis 90.

Wherein, the first welding unit 10 has: possess direction of the supply B supply the first weldering from the top to the bottom in figure First feedway 11 of the first donor rollers 11a of silk 110 and supply weldering with contacting with the first welding wire 110 supplied Connect first source of welding current 12 that the first contact chip 12a of electric current (the first welding current) connects.It addition, the first welding unit 10 It is also equipped with debatching the first welding wire 110 and becomes the reel (not shown) of supply source of the first welding wire 110.

It addition, the second welding unit 20 has: possess direction of the supply B supply the second weldering from the top to the bottom in figure Second feedway 21 of the second donor rollers 21a of silk 120 and supply weldering with contacting with the second welding wire 120 supplied Connect second source of welding current 22 that the second contact chip 22a of electric current (the second welding current) connects.It addition, the second welding unit 20 It is also equipped with debatching the second welding wire 120 and becomes the reel (not shown) of supply source of the second welding wire 120.

And then, the 3rd welding unit 30 has: possess direction of the supply B supply the 3rd weldering from the top to the bottom in figure 3rd feedway 31 of the 3rd donor rollers 31a of silk 130 and supply weldering with contacting with the 3rd welding wire 130 supplied Connect the 3rd source of welding current 32 that the 3rd contact chip 32a of electric current (the 3rd welding current) connects.It addition, the 3rd welding unit 30 It is also equipped with debatching the 3rd welding wire 130 and becomes the reel (not shown) of supply source of the 3rd welding wire 130.

And, the 4th welding unit 40 has: possess direction of the supply B supply the 4th weldering from the top to the bottom in figure 4th feedway 41 of the 4th donor rollers 41a of silk 140 and supply weldering with contacting with the 4th welding wire 140 supplied Connect the 4th source of welding current 42 that the 4th contact chip 42a of electric current (the 4th welding current) connects.It addition, the 4th welding unit 40 It is also equipped with debatching the 4th welding wire 140 and becomes the reel (not shown) of supply source of the 4th welding wire 140.

It is explained, in the welder 1 of present embodiment, chassis 90 carries first source of welding current 12, second The source of welding current the 22, the 3rd source of welding current 32 and the 4th source of welding current 42, and according to making the first source of welding current 12～the 4th welding The mode that power supply 42 runs together with chassis 90 is constituted, but is not limited to this.For example, it is also possible to by these the first welding electricity Source 12～the 4th source of welding current 42 are fixedly arranged on the outside of chassis 90, use cable etc. to be welded by first source of welding current 12～the 4th Connect power supply 42 to be connected with each element on chassis 90.

It addition, the first welding flux feeding device 70 possesses will be contained in table solder flux first weldering of lower section supply in figure of inside Agent supply mouth 70a.And, the quantity delivered of table solder flux based on the first welding flux feeding device 70 supplies by being arranged at the first solder flux The valve (not shown) of device 70 adjusts.

And then, the second welding flux feeding device 80 possesses will be contained in table solder flux second weldering of lower section supply in figure of inside Agent supply mouth 80a.And, the quantity delivered of table solder flux based on the second welding flux feeding device 80 supplies by being arranged at the second solder flux The valve (not shown) of device 80 adjusts.

In this welder 1, from the point of view of moving direction A, it is configured as the first welding wire of the first electrode in most downstream side 110, it is configured as the second welding wire 120 of the second electrode in the more upstream side of the first welding wire 110, more going up of the second welding wire 120 Trip side is configured as the 3rd welding wire 130 of the 3rd electrode, in the further downstream of the 3rd welding wire 130 and is configured as side, most upstream 4th welding wire 140 of the 4th electrode.It addition, in this welder 1, the first welding flux feeding device 70 is arranged in from moving direction The further downstream of the first welding wire 110 from the point of view of A, the second welding flux feeding device 80 is arranged in the second weldering from the point of view of moving direction A The more upstream side of silk 120 and be the further downstream of the 3rd welding wire 130.And, when observing welder 1 above from figure, the One solder flux supply mouth 70a, first welding wire the 110, second welding wire the 120, second solder flux supply mouth 80a, the 3rd welding wire 130 and the 4th weldering Silk 140 arranges along the straight line along moving direction A successively.

It addition, in this welder 1, as the first welding wire 110～the 4th welding wire 140, use respective a diameter of More than 2.4mm and the welding wire of below 6.4mm.Here, for the first welding wire 110～the 4th welding wire 140,4 can be made all For identical diameter, it is possible to so that 3 for identical diameter, another is different diameter, it is possible to so that 2 is identical Diameter and other 2 is other same diameter, it is also possible to make 4 all different diameters.

And then, the first welding wire 110 used in this welder 1～the 4th welding wire 140 are respectively by not having The solid welding wire of solder flux is constituted.However, it is possible to so that more than 1 in them is made up of flux-cored wire.

It is explained, in the following description, sometimes the first welding unit 10 comprising the first welding wire 110 is referred to as " first Row electrode ".It addition, sometimes by the second welding unit 20 comprising the second welding wire 120, the 3rd welding that comprises the 3rd welding wire 130 Unit 30 and the 4th welding unit 40 comprising the 4th welding wire 140 are referred to as " rear row electrode ".And then, sometimes will comprise the second weldering Second welding unit 20 of silk 120 is referred to as " the first target ", is referred to as by the 3rd welding unit 30 comprising the 3rd welding wire 130 " the second target ", becomes " final electrode " by the 4th welding unit 40 comprising the 4th welding wire 140.

Fig. 2 is each welding for illustrating to constitute the first welding unit 10 of welder 1～the 4th welding unit 40 Power supply (first source of welding current 12～the 4th source of welding current 42) and feedway (the first feedway 11～the 4th feedway 41) figure of composition.Here, Fig. 2 represents each welding unit, the power supply mode of each source of welding current and external behavior and respectively supplies Relation to the wire speed control mode of device.

First, the first welding unit 10 is illustrated.

Constitute first source of welding current 12 of the first welding unit 10 for using AC (Alternating Current) as supplying Alternating current power supply electrically, its external behavior is constant voltage characteristic.It addition, the first feedway 11 carries out supplying with constant speed To the fixed speed control of the first welding wire 110 as wire speed control mode.

Then, the second welding unit 20 is illustrated.In the present embodiment, the second welding unit 20 is by following description 5 combinations (first constitute～the 5th constitute) in any one constitute.

A () first is constituted

Second source of welding current 22 in first composition is to use DC (Direct Current) as the direct current of power supply mode Power supply, its external behavior is constant voltage characteristic.It addition, the second feedway 21 in the first composition carries out supplying with constant speed To the fixed speed control of the second welding wire 120 as wire speed control mode.

B () second is constituted

Second source of welding current 22 in second composition is to use AC as the alternating current power supply of power supply mode, and its external behavior is Constant voltage characteristic.It addition, the second feedway 21 in the second composition carries out supplying the perseverance of the second welding wire 120 with constant speed Speed controls as wire speed control mode.So, second becomes the combination identical with the first welding unit 10.

C () the 3rd is constituted

Second source of welding current 22 in 3rd composition is to use AC as the alternating current power supply of power supply mode, and its external behavior is Constant current characteristic.It addition, the second feedway 21 in the 3rd composition is carried out by feedback control based on arc voltage Gradually supply voltage FB (Feed Back) speed Control of the second welding wire 120 as wire speed controlling party using suitable speed Formula.

D () the 4th is constituted

Second source of welding current 22 in 4th composition is to use AC as the alternating current power supply of power supply mode, and its external behavior is Droop characteristic.It addition, the second feedway 21 in the 4th composition is carried out by feedback control based on arc voltage gradually The voltage FB speed Control of the second welding wire 120 is supplied as wire speed control mode using suitable speed.

E () the 5th is constituted

Second source of welding current 22 in 5th composition is to use DC as the DC source of power supply mode, and its external behavior is Constant current characteristic.It addition, the second feedway 21 in the 5th composition is carried out by feedback control based on arc voltage Gradually supply the voltage FB speed Control of the second welding wire 120 as wire speed control mode using suitable speed.

It addition, as the second welding unit 20, the 3rd welding unit 30 and the 4th welding unit 40 can also be by above-mentioned The first composition (a)～the 5th any one constituted in (e) constitute.Here, with regard to the second welding unit the 20, the 3rd welding unit 30 and the 4th for welding unit 40, can make 3 all identical compositions, it is possible to so that 2 another for identical composition One is different compositions, it is also possible to make 3 all different compositions.

Being explained, the feed speed of the first welding wire 110～the 4th welding wire 140 can be based on the moving direction to chassis 90 The translational speed (speed of welding) of A determines.Such as in the case of fixed speed control, operator determines confession based on speed of welding To the reference value of speed, and carry out fixed speed control in the way of maintaining the reference value of this feed speed.It addition, such as at voltage In the case of FB speed Control, operator determines the reference value of feed speed on the basis of speed of welding, and to supply speed The reference value feedback arc voltage of degree carries out speed Control.

Then, the external behavior of above-mentioned each source of welding current is illustrated.

Fig. 3 is the figure of the external behavior for the source of welding current is described.Here, Fig. 3 (a) exemplifies constant voltage characteristic, Fig. 3 B () exemplifies constant current characteristic, Fig. 3 (c) exemplifies droop characteristic.It addition, in each figure of Fig. 3 (a)～(c), transverse axis is Output electric current I (A), the longitudinal axis is output voltage V (V).According to the instruction of the curtage being input to the source of welding current, external behavior Curve is moved (change).Fig. 3 (a) exemplifies the external characteristic curve corresponding with the instructed voltage in 4 stages, it addition, Fig. 3 (b)～(c) exemplify the external characteristic curve corresponding with the indicator current in 4 stages.It is explained, at the source of welding current In the case of, electric current I is corresponding with welding current in output, output voltage V and in addition other losses of voltage will be because of in arc voltage The aggregate value of (cable internal consumption, contact resistance etc.) is corresponding.

First, the constant voltage characteristic shown in Fig. 3 (a) is illustrated.

In the case of constant voltage characteristic, for the variation of output electric current I, the variation of output voltage V diminishes.

Then, the constant current characteristic shown in Fig. 3 (b) is illustrated.

In the case of constant current characteristic, for the variation of output electric current I, the variation of output voltage V becomes big. If by it from the viewpoint of contrary, then in constant current characteristic, even if output voltage V occurs significantly to change, export electric current I Variation the least.

Then, the droop characteristic shown in Fig. 3 (c) is illustrated.

In the case of droop characteristic, as the situation of constant current characteristic, relative to output electric current I variation and Speech, the variation of output voltage V becomes big.But, in the case of droop characteristic, compared with the situation of constant current characteristic, output The variation of voltage V is mild, and changes with current value.

Here, Fig. 3 (a)～(c) also illustrate to produce the electricity of the electric arc of welding arc length L together with each external behavior Arc property.In the various figures, the curve of arbitrary external behavior becomes generation target welding arc length L with the intersection point of the curve of arc characteristic The operating point P (specific output electric current I and corresponding specific output voltage V) of electric arc.It is explained, following In explanation, operating point P, the voltage versus current slope being used for producing the electric arc of target welding arc length L is referred to as differential value dV/dI。

Here, there is droop characteristic, the source of welding current of constant current characteristic is suitable for burying because the variation of depth of penetration is little Arc-welding.But, in the source of welding current with droop characteristic, constant current characteristic, arc voltage is susceptible to change, therefore leads to The most combined with the supply of welding wire based on voltage FB speed Control.In the welding by having droop characteristic, constant current characteristic In the case of power supply combines with voltage FB speed Control, if welding arc length L shortens, then dropped by the reduction according to arc voltage The feed speed of low welding wire, so that welding arc length L returns to the original length, on the other hand, if welding arc length L is elongated, then leads to Cross the feed speed improving welding wire according to the rising of arc voltage, so that welding arc length L returns to the original length.

On the other hand, the extremely active gas of metal of the welding wire that the source of welding current with constant voltage characteristic is adapted for use with thin footpath Body shielded arc welding (MAG weldering), MIG (metal intert gas) welding (MIG weldering).It addition, have the welding electricity of constant voltage characteristic Source has been also used for the submerged-arc welding of the welding wire of below diameter 2.0mm sometimes.But, there is the welding electricity of constant voltage characteristic In source, welding current is susceptible to change, therefore the most combined with the supply of welding wire based on fixed speed control.To have perseverance In the case of the source of welding current of constant voltage characteristic combines with fixed speed control, if welding arc length L shortens, then by making welding current certainly Dynamic change is big, so that welding arc length L returns to the original length, on the other hand, if welding arc length, then by making welding current Automatically diminish, so that welding arc length L returns to the original length.

It follows that feature of the welding condition of the multi-electrode one side submerged-arc welding method to present embodiment is said at this Bright.

＜ is about the diameter ＞ of each welding wire

In one side submerged arc welding method, need to make groove fusing form root pass under hard arc power.But, not single Being singly that welding current is the highest more good, if making welding wire major part melt under at a high speed supply, then causing retaining immediately below electric arc molten Liquid, himself makes arc force be buffered, makes penetration diminish.Accordingly, it would be desirable to the high still welding wire melting amount of welding current is not Many, that meet this condition is electric current density (A/mm²) low condition, i.e. welding wire footpath be thicker, and be suitable for supplying welding wire with low speed. The welding wire in the thin footpath of below diameter 1.6mm is generally used in gas shielded arc welding, but, used for submerged arc welding as one side, suitable Close is the welding wire of more than diameter 2.4mm.It is preferably to use preferred more than diameter 3.2mm and then the weldering of diameter more than 4.8mm Silk.To the technology setting the upper limit, there is no particular restriction, from the supply of welding wire, the aspect of cutting, a diameter of 6.4mm with Under be more practical.

＜ is about quantity ＞ of electrode

Leading electrode has the effect making groove melt deeper and to form fusion pool and root pass, and welding condition is this Effect is specific, the surface that makes fusion pool arrive mother metal even if therefore the thickness of slab of mother metal is relatively thin, also will not make unipolar Table welding bead outward appearance is good.On the other hand, final electrode mainly has the effect of the outward appearance of finishing table welding bead, therefore its welding condition Different from leading electrode.So need, in one side submerged-arc welding, the effect of sharing, it is therefore desirable to use the how electricity of the welding wire of more than 2 Polarization.Generally, along with the thickness of slab of steel plate is thickening, the quantity of welding wire increases.The technology of the quantity set upper limit of electrode be there is no spy Do not limit, as single-sided welding purposes, such as, be practical to 4 electrode systems shown in Fig. 1.

The interval of appropriateness is set between each electrode.Supply thickness of slab, speed of welding, bonding machine used, welding wire is each Plant control cannot treat different things as the same, can suitably adjust.It is explained, the supply mouth of solder flux is the most also set between electrode (the first solder flux supply mouth 70a shown in Fig. 1, the second solder flux supply mouth 80a).

＜ is about wire speed control mode, external behavior and power supply mode ＞ of leading electrode

[about the wire speed control mode of leading electrode]

In multi-electrode one side submerged-arc welding, leading electrode is primarily used to form root pass.The present inventor etc. find: at root In portion's welding, the driving force of penetration can interfere significantly on root quality, easily occurs that the surplus of root pass or root are not enough.And And, the driving force of penetration is tested by the present inventor etc. repeatedly, finds: correct in common interface current and voltage factor, But electric current and voltage factor incorrect in single-sided welding, the disturbance degree of the feed speed of welding wire is maximum.

That is, if the feed speed excess of welding wire, then welding wire easily will be depressed into by the fusion pool of surface tension body supports The steel plate back side, excessively forms root.And then, if feed speed accelerates, welding wire the most also can be made to puncture fusion pool.

On the contrary, if the feed speed of welding wire is not enough, then fusion pool will not be squeezed from the steel plate back side, then make root not Foot.These phenomenons should be unable to make the change of the feed speed of welding wire welding arc length L for being inevitably generated in theory React and make welding arc length L return to original state with changing no time lost.But, supply the welding wire of welding wire in practice Electromotor is industrial product, produces a certain degree of delay in the reaction.Delay to this response time, the height of root pass Not there is firm character and be easily subject to the impact of its change.

In view of this problem understands, even if to being formed in the leading electrode that impacts of root weld what be desired is that electric current, electricity Pressure changes, and does not impacts feed speed, control (fixed speed control) that feed speed is constant.Its reason is: as Upper described, carrying out welding wire supply constant control up to now in particle size submerged-arc welding is conventional inapplicable control methods.As it Reason, particle size welding wire is difficult to make gross section equally melt, and result makes welding wire melt speed destabilization, and then also cannot the phase The stabilisation of arc length degree L to be welded.But, as long as being formed in the case of root pass with single-sided welding, steady with welding arc length L Determining is compared, and feed speed stabilisation more makes dimensionally stable effect high.

[about the external behavior of leading electrode]

It follows that be the external behavior of leading electrode, common-sense have the droop characteristic as prior art.With regard to sagging spy For property, as it has been described above, the variation of relative voltage value, the variation of current value is less.As simple in construction and cheap, safeguard easily Bonding machine structure, do not use electronics element, and use the iron core that make use of leakage reactance component can all the time Dynamic formula bonding machine, the most also has the epochal character problem that only droop characteristic works.

Current value is applied when the non-root weld most affected depth of penetration effective to penetration stabilisation, but for For the dimensionally stable of the root pass that face wave soldering connects, the factor of influence that the variation of current value is the most upper.On the other hand, Although compared with the variation of feed speed, welding arc length L is also little on the impact of root stabilisation, but welding arc length L occurs When the most drastically changing, harmful effect can be brought.Such as, if welding arc length L be zero, i.e. electric arc disappear, cause welding itself Terminate, or produce electric arc when scratch start again explosion type, therefore cannot be normally formed root pass with this power.The opposing party Face, if welding arc length L is excessive, is the most still unable to maintain that electric arc makes electric arc disappear immediately, or makes the electric arc of per unit area Power reduces, it is impossible to form root pass.

And then, cause produce welding weld bead shape irregular, offset by what arc blow affected, cut out and dig caused by mother metal The defect such as undercutting.That is, it needs to the Stabilization Control of welding arc length L.

If for root stabilisation premised on supply constant airspeed, then as making the means of welding arc length L stabilisation, Need the control object in addition to feed speed control.The melted speed of known self-consuming electrode type welding welding wire carrys out table with formula (1) Show, imply current value (welding current I) square disturbance degree maximum.

Mw=K1 I+K2 I²·ρ·L…(1)

Mw: welding wire melts speed

I: welding current

ρ: resistivity

L: welding wire highlights length

K1, K2: constant

Thus, make the means of welding arc length L stabilisation as premised on supply constant airspeed, effectively actively make Welding current I changes.Such as, if welding arc length L shortens, then by making welding current I steeply rise, thus welding wire melts Speed Mw reduces, and makes welding arc length L return to original state.On the other hand, if welding arc length L is elongated, then by making electric current anxious Fall sharply low, thus welding wire melts speed Mw and rises, and still makes welding arc length L return to original state.This phenomenon is commonly referred to as The self-contr ol effect of welding arc length.The drastically change of electric current is needed in the self-contr ol effect of welding arc length, it is achieved its External behavior is only constant voltage characteristic.Therefore, in order to realize for making the welding wire feed speed needed for root weld stabilisation Constant, as the indirect factor, needing the external behavior making the source of welding current corresponding with leading electrode is constant voltage characteristic.

This kind " wire speed controls: constant speed " and the combination of " external behavior: constant voltage characteristic " are used in employing diameter In the gas shielded arc welding method of the thin welding wire of below 1.6mm.This be due to: make meltbility excellent, therefore owing to welding wire is thin The self-contr ol effect of welding arc length is highly effective.But, for the welding wire of a diameter of more than 2.4mm, with the weldering thinner than it Silk is compared, and meltbility is deteriorated, if for non-single-sided welding, then the self-contr ol effect of welding arc length cannot play work observantly With, cause electric arc and weld bead shape is unstable.

[about the power supply mode of leading electrode]

It follows that be the power supply mode of leading electrode, single fillet welded leading electrode needs exchange.At multi-electrode list In the submerged-arc welding of face, owing to the electric current of each electrode is high, therefore produce stronger around current path along with the supply of electric current Magnetic field.If each electrode is close together, then occur the interaction in magnetic field, so-called electric arc the most dry, or occur by joining Electricity or the magnetic force caused by arc blow of mother metal of resulting from, therefore make electric arc destabilization.This kind of phenomenon is at magnetic direction fixing Becoming notable under direct current, if using exchange, then owing to losing directivity, therefore the harmful effect to electric arc is greatly reduced. Therefore, for whole electrodes, it is preferably exchange, but the leading electrode that minimum is also required to forming root pass uses Exchange.

Based on reason illustrated above, leading electrode uses " wire speed controls: constant speed ", " external behavior: constant voltage Characteristic " and the combination of " power supply mode: exchange ".

Being explained, present most popular big electric current submerged arc welding machine is the AC machine of cheap iron core operation type.The party In formula, necessarily making external behavior is droop characteristic.In the present invention, leading electrode on this point of AC machine be general in the past , but external behavior be constant voltage characteristic be different on this point.This combination cannot utilize common iron core to work Formula obtains.In order to obtain constant voltage characteristic, it is possible to by using the electronics element of thyristor, inverter etc Circuit design generates.Or, also have and obtain by only using the side, low current territory of iron core operation type that maximum current capacity is big Any special measures to the constant voltage characteristic in practical territory.

＜ is about wire speed control mode, external behavior and power supply mode ＞ of rear row electrode

Although can not be visually confirmed to be in multi-electrode one side submerged-arc welding, but institute in the table solder flux being piled up on steel plate The fusion pool formed is the huge liquid being referred to as integral pool (one pool) being substantially connected by the motlten metal of whole welding wires Body metal.As it has been described above, leading electrode has a disturbance degree that the shape to root pass is maximum, but if integral pool, although Disturbance degree diminishes relatively, but the shape of root pass also can be impacted by rear row electrode.Such as, even if becoming leading electricity First electrode of pole can form the root pass of the liquid condition of excellent in shape, if after becoming the second electrode of row electrode with After according to will be formed with the first electrode fusion pool rearwardly side extrude mode play a role, the root of the most final curdled appearance Portion's welding bead becomes irregular.Therefore, can also apply in the same manner as leading electrode after the second electrode " wire speed controls: Constant speed " and " external behavior: constant voltage characteristic ".Here, power supply mode expectation is all with leading electrode and to exchange, the second electrode with After the disturbance degree of polarity relatively diminish than the first electrode, even if the most also having practicality.

On the other hand, if the thickness of slab of steel plate is thickening and make electrodeplate also become many, although being then integral pool, even if at rear row electricity The pressure of the fusion pool that pole is formed has a little change, also will not cause in the rear side apart from remote fusion pool and significantly affect. Can also apply in this case " wire speed control: voltage FB speed Control " all the time used and " external behavior: Droop characteristic ".The weldering of " external behavior: constant current characteristic " that destination properties is identical even if certainly using replacement droop characteristic Connect power supply and also will not constitute problem.Rear row electrode also needs to the effect with the shape of finishing table welding bead sometimes, even if based on this Purpose and change feed speed, it is also effective for preferentially making current value, welding arc length L stabilisation.For this kind of requirement, " silk speed Degree controls: voltage FB speed Control ", " external behavior: droop characteristic or constant current characteristic " and be difficult to cause electric arc mutual Dry or by " power supply mode: exchange " of the deflection caused by arc blow combination is the most suitable.

Other ＞ of ＜

[about liner]

In single-sided welding, usual use band blocks copper or the liner material of soild oxide of the groove of root pass.Give With explanation, soild oxide particularly belongs to ceramic or glass.In the case of glass, generally use fiberglass braided one-tenth Ribbon glass.If not liner material, then superfluous arc force makes fusion pool fall when working bonding layer, and electric arc disappears, It is absorbed in the situation that can not proceed welding.If using some liner materials, then it is possible to prevent this kind of worst state of affairs.

If the steel plate bottom surface becoming mother metal can be closely sealed, even if then arc force is unstable, the shape of root pass also should be steady Fixedization, but, the biggest steel plate out-of-flatness and bend somewhat or fluctuating can occur mostly, therefore may not be closely sealed.To this end, In order to fill the gap between the steel plate bottom surface and liner material being inevitably generated, sometimes to spread liner solder flux in advance.This Sample one, it is possible to prevent the hanging of fusion pool of rear side to a certain extent.And then, also by not laying liner material and thicker Ground spreads liner solder flux and carrys out compressed against gasket solder flux to injecting gas at its lower air hose laid, improve the side of adaptation Method.Now, in order to prevent fusion pool from hanging in liner solder flux, the powder layer stack structure with curable resin is the most also made.

[about table solder flux]

Owing to being the basic composition of the minimum as submerged-arc welding, therefore without special instruction, but, solder flux is loaded into It is referred to as the container (first welding flux feeding device the 70, second welding flux feeding device 80 shown in Fig. 1) of the lower section band flexible pipe of hopper In, along with the carrying out of welding, from the dead ahead of leading electrode or be further disposed upon interelectrode flexible pipe front end as desired Solder flux supply mouth spread with permanent constant speed.

[about groove packing material]

If spreading steel or the steel alloy of powder shaped in advance in groove, then melt when welding and form the one of motlten metal Part.In addition to high-duty effect, in the case of local, welding bead gap is excessive, it is difficult to extract root out.And then, also there is increasing Rate of cooling near big weld part and effect that the quality of mother metal heat affected zone that suppresses deteriorates.Weld it addition, also have at root Supply the welding wire of the first electrode later rear row electrode when connecing, make electric arc instability obtain the effect relaxed.But, if dispersion volume Too much, then cannot all melt and remain with the state of solid, sometimes become defect, distribution that therefore can not be excessive.By electric current, The balance of bevel shape determines optimised quantity.As the material of powder body, use the iron powder of so-called fine size, the welding in thin footpath is welded Silk cutting and become thick granular.

[about the differential value of the weldingvoltage with constant voltage characteristic]

Generally, for bonding machine, record in the item such as constant voltage characteristic, droop characteristic, constant current characteristic Specification, therefore its characteristic is seldom accurately investigated by user side.But, the entitled diagrammatic life of these external behaviors Name, there is no quantitative definition.Recently, user also releases the type that can adjust external behavior.It is expected to as operating point The slope of voltage-current characteristic of the constant voltage characteristic in electric current, i.e. differential value dV/dI are positioned at-12.0 × 10^-3(V/A) Horizontal side.In other words, differential value dV/dI is-12.0 × 10^-3(V/A) more than.If differential value dV/dI is-12.0 × 10^-3 (V/A) more than, then the change of corresponding welding arc length L and make electric current occur significantly to change, effectively play the oneself of welding arc length L Control action, thus ideal.More preferably, if differential value dV/dI is-8.0 × 10^-3(V/A) more than, then root shape More stabilisation.It is explained, as the external behavior general aspects including constant voltage characteristic, it is impossible to become+side Slope, therefore the actual upper bound of differential value dV/dI is 0.

[about the differential value of the weldingvoltage with constant current characteristic or droop characteristic]

Also quantitative definition cannot be enumerated for constant current characteristic and droop characteristic.Constant current characteristic and sagging spy Property it is believed that difference be that use rectifier cell and generate or utilize the leakage magnetic flux caused by iron core works, but, shortly Make welding arc length L change also and can ensure that current constant is identical on this point.At constant current characteristic and droop characteristic In the common slope of preferable voltage-current characteristic, i.e. the differential value dV/dI of operating point electric current be in-24.0 × 10^-3 (V/A) vertical side, in other words, preferable differential value dV/dI is-24.0 × 10^-3(V/A) below.If by differential value dV/dI For-24.0 × 10^-3(V/A) characteristic below and the Voltage Feedback control combination of feed speed, then can pass through to catch sensitively Catch arc voltage change, change feed speed to measure the stabilisation of welding arc length L, contribute to stablizing of table weld bead shape Change.It is explained, as the external behavior general aspects comprising constant current characteristic and droop characteristic, it is impossible to become+side Slope, therefore actual lower limit is-∞ (infinitely great).

Embodiment

Hereinafter, based on embodiment, the present invention will be described in more detail.But, the present invention is without departing from its purport then It is not limited to below example.

(first embodiment and the first comparative example)

Fig. 4 is the figure of the composition of the experimental provision for first embodiment and the first comparative example are described.It is explained, Fig. 4 The basic composition of shown experimental provision is general with the welder 1 shown in Fig. 1.Here, Fig. 4 illustrates in the lump with experimental provision Comprise the first steel plate 201 and the workpiece 200 of the second steel plate 202, be supplied to the table solder flux 300 of the face side of workpiece 200, be configured at The cushion part 400 of the rear side of workpiece 200, it is formed at the welding metal 500 of workpiece 200 with welding.

It addition, Fig. 7 (a) illustrates first embodiment and each steel plate of the first comparative example and the size of groove.In this embodiment, The thickness of slab 35mm that one steel plate 201 and the second steel plate 202 use tensile strength to be 490MPa level, wide 500mm × long 3000mm carbon steel Plate, and carry out groove end face processing respectively, make banjo fixing butt jointing.Bevel shape is 45 ° of V-types from a surface to 29mm, remains plate Thick 6mm is vertical as root root face.Root gap is set to 0mm with the shortest portion contact both sides steel plate, but exists because of steel plate Strain and be inevitably generated the position in the gap of maximum 2mm.Each welding wire (first welding wire 110～the 4th welding wire 140) makes With JIS Z3351YS-S6 specification product, table solder flux 300 uses JIS Z3352SACI1 specification product.At the first electrode (electricity in advance Pole) more front and the second electrode and the 3rd electrode between spread continuously appropriate table solder flux 300 automatically.

Inside divided edge of steel plate, lay band spread the liner copper coin 402 of groove of a small amount of liner solder flux 401 as cushion part 400.It addition, between the contact chip corresponding with each electrode and steel plate the source of welding current of wiring independence.It is explained, each welding wire The donor rollers of the surface being arranged at each contact chip delivers to weld part.

And, use the experimental provision shown in Fig. 4, carry out the test of four electrode one side submerged-arc welding methods.More specifically, Use the assay device shown in Fig. 4, to each electrode change gage of wire, power supply mode, external behavior, wire speed control, Welding current, arc voltage, confirm that it affects.In the experimental provision shown in Fig. 4, the front end of the first welding wire 110 and the second weldering The interelectrode distance of the front end of silk 120 is set to 40mm, between the electrode of the front end of the second welding wire 120 and the front end of the 3rd welding wire 130 Distance is set to 120mm, and the front end of the 3rd welding wire 130 is set to 30mm with the interelectrode distance of the front end of the 4th welding wire 140.And, Speed of welding in this example is all 44 (cm/min).

It addition, as result of the test, root pass shape, table weld bead shape, internal flaw are evaluated.With regard to root For weld bead shape, with width as 10mm more than, root height as 2mm more than and below 6mm ideal, and with skew The situation that deviation little, width is little is set to be the most well A, evaluates poor by some these but arrive the degree needing correction Situation be set to B, root pass shape defect needs situation about revising, and to be set to C the most defective.For table weld bead shape also Set the metewand as root pass shape.For internal flaw, though will carry out ultrasonic test, section grand See notch test and also do not observe that the situation of defect is set to "None", will confirm that the bad situation of fusion is set to " having ".

Manufacturing condition in first embodiment and the first comparative example and result of the test are shown in table 1 and table 2.Here, table 1 institute No.1-1～No.1-5 shown is first embodiment, No.1-6～No.1-11 shown in table 2 is the first comparative example.

Be explained, in the power supply mode shown in table 1 and table 2, " AC " refer to exchange, " DC (EP) " refer to direct current and with Welding wire i.e. electrode side is " the Electrode Plus " of positive pole, and " DC (EN) " refers to direct current and with welding wire i.e. electrode side as negative pole “Electrode Negative”.This is marked in table 3 described later～table 6 also synonym.

[table 1]

[table 2]

First, first embodiment is illustrated.

In No.1-1, although the first electrode uses AC constant voltage characteristic fixed speed control, and the second electrode makes later With all the time exchange droop characteristic voltage FB speed Control, but obtain good root pass shape.It addition, it is logical Cross and be set to the 4th electrode becoming final passage exchange droop characteristic voltage FB speed Control, thus table weld bead shape is also The best.

No.1-2 be the differential value dV/dI of the external behavior of the source of welding current of the first electrode compared with No.1-1 less, The situation that i.e. constant voltage characteristic weakens, therewith, the self-contr ol effect of the welding arc length in the bonding layer welding of the first electrode subtracts Weak and destabilization, therefore root pass shape is the poorest compared with No.1-1.It is to say, owing to using exchange constant speed control System, therefore obtains the root pass shape being in permissible range.

No.1-3 with No.1-1 is similar, but not only the first electrode is set to AC constant voltage characteristic constant speed control System, and the second electrode is also set to AC constant voltage characteristic fixed speed control as the first electrode.By making root The impact that the quality of weld bead shape causes is only second to the second electrode of the first electrode and is also adopted by fixed speed control, thus compares No.1-1 Further improve the quality of root pass shape.

In No.1-4, whole electrodes being set to constant voltage characteristic fixed speed control, the only second electrode is set to direct current, its He is all set to exchange.By the most full electrode is taked to reduce the control of the pressure change of fusion pool, thus obtain the best Root pass shape.It addition, the 3rd electrode of disposable sheet weld bead shape, the 4th electrode is set to will not be the most dry by electric arc , the exchange of impact of arc blow, therefore obtain table weld bead shape the most excellent in first embodiment and root pass shape.

As No.1-5 with No.1-4, whole electrodes are set to constant voltage characteristic fixed speed control, but, by second Direct current it is all set to after electrode.If different from No.1-4, direct current is arranged in nearer distance, then causes electric arc the most dry And bring impact, therefore in permissible range, if compared with No.1-1～No.1-4, then welding bead outward appearance is the poorest.

Then, the first comparative example is illustrated.

No.1-6 is the typical case being presently using.All electrode uses exchange droop characteristic voltage FB speed change control System.The variation of feed speed can make root fusion pool unstable, although internal flaw, table weld bead shape are the most particularly asked Topic, but it is unsuitable for root weld, make the bad of root pass shape become notable.

No.1-7 is the situation making the 4th application of electrode constant voltage characteristic fixed speed control compared with No.1-6, i.e. Making only to be reduced the 4th electrode becoming final electrode the control of the pressure change of fusion pool, contribution rate is also than the first electrode Low, the most do not improve root pass shape.

No.1-8 with No.1-6, No.1-7 are similar, but the second application of electrode constant voltage characteristic fixed speed control. But, compared with the first electrode, become the pressure that the fusion pool forming root pass is applied by the second electrode of the first dynode Stabilisation contribution rate relatively low, it is impossible to obtain the improvement effect of root pass shape.

No.1-9 is that the first electrode, the second electrode are all when the source of welding current of conventional exchange droop characteristic Welding wire supply is set to the situation of fixed speed control.For droop characteristic, welding arc length stabilisationization should pass through welding wire in theory Supply controls and realizes, but owing to carrying out constant speed, therefore the effect of welding arc length stabilisation does not plays a role completely.Therefore, Welding arc length often occurs significantly to change, it is impossible to stable welding.Result: root pass shape and table weld bead shape is the most coarse and Instability, also creates fusion bad in inside.

No.1-10 is that the first electrode is set to direct current constant current characteristics, on the other hand controls to be set to perseverance by wire speed The composition that speed controls.The source of welding current of direct current constant current characteristics is not by common non-consumable electrode type, i.e. consumable welding wire Produce electric arc but produced the electricity used in the gas tungsten arc welding of electric arc, plasma welding method by on-consumable tungsten electrode Source mode, about the control of welding arc length, identical with droop characteristic, need to be in the upper and lower of electrode side.Even if this power supply is with molten Pole formula uses, and in the case of welding wire is carried out fixed speed control, does not plays welding arc length stabilisation effect the most completely.Therefore, As No.1-9, welding arc length often occurs significantly to change, it is impossible to carry out stable welding.Root pass shape and table welding bead Shape is the most coarse and unstable, also creates fusion in inside bad.

In No.1-11, conventional full electrode is become direct current from exchange droop characteristic voltage FB speed Control permanent Determine current characteristics voltage FB speed Control, but the first electrode not AC constant voltage characteristic fixed speed control, therefore Root pass shape destabilization.For table weld bead shape, constant current characteristic voltage FB speed Control plays a role, Although observe by the most dry caused unstability of the distinctive electric arc of direct current, but in permissible range.

(the second embodiment and the second comparative example)

Fig. 5 is the figure of the composition of the experimental provision for the second embodiment and the second comparative example are described.It is explained, Fig. 5 Substantially being configured to of shown experimental provision removes the 4th welding unit 40 from the welder 1 shown in Fig. 1.Here, in Fig. 5 with Experimental provision illustrates the face side comprising the first steel plate 201 and the workpiece 200 of the second steel plate 202, being supplied to workpiece 200 in the lump Table solder flux 300, be configured at the rear side of workpiece 200 cushion part 400, with welding and be formed at the welding metal of workpiece 200 500。

It addition, Fig. 7 (b) illustrates the second embodiment and each steel plate of the second comparative example and the size of groove.In this embodiment, Thickness of slab 30mm that one steel plate 201 and the second steel plate 202 use tensile strength to be 490MPa level, the carbon of wide 500mm × long 3000mm Steel plate, and carry out groove end face processing respectively, make banjo fixing butt jointing.Bevel shape is from a surface to 45 ° of V-types till 25mm, Thickness of slab 5mm is vertical as root root face for residue.Root gap is set to 0mm with the shortest portion contact both sides steel plate, but exists The position in the gap of maximum 2mm it is inevitably generated because of the strain of steel plate.Each welding wire (the first welding wire 110～the 3rd welding wire 130) using JIS Z3351YS-S6 specification product, table solder flux 300 uses JIS Z3352SACI1 specification product.At the first electrode (first Row electrode) more front and the second electrode and the 3rd electrode between spread continuously appropriate table solder flux 300 automatically.

Do not use inside divided edge of steel plate the such formation solid of copper coin, ceramic wafer as cushion part 400, and in lower surfacing The liner solder flux 412 that there was added curable resin composition on a small quantity is spread in agent 411, and from being passed through the inside of lower surfacing agent 411 Air hose 413 injects gas, thus liner solder flux 412 is placed in the steel plate back side.It addition, in the contact corresponding with each electrode The source of welding current of wiring independence between chip and steel plate.Being explained, each welding wire is arranged at the surface of each contact chip Donor rollers delivers to weld part.

And, use the experimental provision shown in Fig. 5, carry out the test of three electrode one side submerged-arc welding methods.More specifically, Use the assay device shown in Fig. 5, to each electrode change gage of wire, power supply mode, external behavior, wire speed control, Welding current, arc voltage, confirm that it affects.In the experimental provision shown in Fig. 5, the front end of the first welding wire 110 and the second weldering The interelectrode distance of the front end of silk 120 is set to 40mm, between the electrode of the front end of the second welding wire 120 and the front end of the 3rd welding wire 130 Distance is set to 120mm.And, the speed of welding in this example is all 47 (cm/min).

As result of the test, root pass shape, table weld bead shape, internal flaw are evaluated.With regard to root pass For shape, with width as 9mm more than, root height as 2mm more than and below 5mm ideal, and little, width will be offset The little situation of deviation be set to be the most well A, some these are evaluated poor but arrive the situation of the degree needing correction It is set to B, root pass shape defect needs situation about revising be set to C the most defective.For table weld bead shape also set with The metewand that root pass shape is same.For internal flaw, though will carry out ultrasonic test, section macroscopic view otch Test does not observes that the situation of defect is set to "None" yet, will confirm that the bad situation of fusion is set to " having ".

Second embodiment and the manufacturing condition of the second comparative example and result of the test are shown in table 3 and table 4.Here, shown in table 3 No.2-1～No.2-4 be the second embodiment, No.2-5～No.2-10 shown in table 4 is the second comparative example.

[table 3]

[table 4]

First, the second embodiment is illustrated.

In No.2-1, the first electrode uses AC constant voltage characteristic fixed speed control, uses one after the second electrode Since Zhi exchange droop characteristic voltage FB speed Control, obtain good root pass shape.It addition, by becoming The 3rd electrode for final passage is set to exchange droop characteristic voltage FB speed Control, thus table weld bead shape is the best Good.

No.2-2 is the differential value of the external behavior of the source of welding current of the second electrode, the 3rd electrode compared with No.2-1 The situation that dV/dI is more greatly, i.e. constant current characteristic weakens.If constant current weakens, then arc voltage is not easy to change, welding arc The feedback control of length is not easy to prove effective.Therefore, although in permissible range, but make compared with root pass shape welding arc The stability of length produces the table weld bead shape of bigger impact and is deteriorated.That is, imply: in order to make table weld bead shape good, differential Voltage FB speed Control little for value dV/dI is more preferably.

In No.2-3, whole electrodes are set to AC constant voltage characteristic fixed speed control, after the second electrode also Take to reduce the control of the pressure change of fusion pool, thus obtain the best root pass shape.It addition, disposable sheet welding bead What the 3rd electrode of shape was set to that the most not dry by electric arc, arc blow affected exchanges, and therefore obtains in the second embodiment Excellent surface back side quality.

In No.2-4, the first electrode uses AC constant voltage characteristic fixed speed control, on the other hand, the second electrode Being set to direct current constant current characteristics voltage FB speed Control, the 3rd electrode is set to AC constant current characteristic voltage FB Speed Control.The DC voltage FB speed Control of the second electrode produces some harmful effects to root shape, therefore obtains Although not being preferably but the root pass shape in permissible range.It addition, it is (final for forming the 3rd electrode of table welding bead Electrode), use the constant current characteristic more excellent than for constant current with droop characteristic, so that welding arc length is more Stable, and obtain the table weld bead shape of excellence.

Then, the second comparative example is illustrated.

No.2-5 be make the first electrode be direct current compared with No.2-1 and and the situation of non-alternating.Direct current is easily subject to Electric arc is the most dry, the impact of arc blow, even if obtaining root pass to a certain extent by welding wire is carried out fixed speed control The static stabilization of shape, is the most still not enough to the most stable shaped.

No.2-6 is the typical case being presently using.All electrode uses exchange droop characteristic voltage FB speed change control System.Although internal flaw, table weld bead shape on the contrary do not have special problem, but speed Control is unsuitable for root weld, makes root Portion's weld bead shape produces bad.

In No.2-7, the second combination of electrodes exchange droop characteristic electric current FB speed Control.With regard to droop characteristic Speech, relative to the variation of welding arc length, electric current less changes, and therefore the feedback control of monitor current is more worse than Voltage Feedback Welding arc length control device.Owing to the control of welding arc length cannot successfully be carried out, and welding wire supplies also and non-constant velocities, The most not only produce the bad of root pass shape, but also produce merge bad internal flaw, table weld bead shape bad.

In No.2-8, whole combination of electrodes AC constant current characteristic electric current FB speed Control.Owing to welding arc is long The control of degree cannot successfully be carried out, and welding wire supplies also and non-constant velocities, the most not only produces root pass shape not Good, and produce merge bad internal flaw, table welding bead outward appearance bad, overall quality is more worse than No.2-7.

In No.2-9, the first combination of electrodes AC constant voltage characteristic voltage FB speed Control.With regard to constant voltage For characteristic, relative to the variation of welding arc length, voltage less changes, and therefore the feedback control of monitoring voltage is long as welding arc The performance of degree control device is low, and for forming the first electrode of root pass, the feed speed of welding wire is constant to shape Stabilisation is most important, does not therefore obtain good root pass shape in this composition.Further, since based at the beginning of the first electrode Layer is the most unstable, thus bad also producing fusion with the junction portion of the second electrode.

In No.2-10, the first combination of electrodes AC constant current characteristic fixed speed control, but in this combination not Carry out the Stabilization Control of welding arc length, therefore weld instability, not only produce the bad of root pass shape, and due to base The most unstable in the bonding layer of the first electrode, thus bad also producing fusion with the junction portion of the second electrode.

(the 3rd embodiment and the 3rd comparative example)

Fig. 6 is the figure of the composition of the experimental provision for the 3rd embodiment and the 3rd comparative example are described.It is explained, Fig. 6 Substantially being configured to of shown experimental provision removes the 3rd welding unit the 30, the 4th welding unit from the welder 1 shown in Fig. 1 40 and second welding flux feeding device 80.Here, Fig. 6 illustrates in the lump with experimental provision and comprises the first steel plate 201 and the second steel plate The workpiece 200 of 202, it is supplied to the table solder flux 300 of the face side of workpiece 200, is configured at the cushion part of the rear side of workpiece 200 400, it is formed at the welding metal 500 of workpiece 200 with welding, is fed into the groove packing material 600 of groove in advance.

It addition, Fig. 7 (c) illustrates the 3rd embodiment and each steel plate of the 3rd comparative example and the size of groove.In this embodiment, The thickness of slab 14mm that one steel plate 201 and the second steel plate 202 use tensile strength to be 520MPa level carbon steel sheet, wide 500mm × length 3000mm carries out groove end face processing respectively, makes banjo fixing butt jointing.Bevel shape is 50 ° of V-types without root root face.Root gap It is set to 0mm with the shortest portion contact both sides steel plate, but exists and be inevitably generated because of the strain of steel plate between maximum 2mm The position of gap.Each welding wire (first welding wire 110 and the second welding wire 120) uses JIS Z3351YS-S6 specification product, table solder flux 300 Use JIS Z3352SACI1 specification product.Appropriate table weldering is spread the most continuously in the more front of the first electrode (leading electrode) Agent 300.It addition, separately the groove packing material 600 comprising iron powder is manually spread in groove with table solder flux 300 in advance. The packed height of groove packing material 600 is managed for distance steel plate surface location 3mm.This groove packing material 600 is in welding Time melt together with each welding wire, table solder flux 300, formed fusion pool.

Do not use the such formation solid of copper coin, ceramic wafer or liner solder flux as cushion part 400 inside divided edge of steel plate And attach the soft liner material 421 being referred to as glass tape thick for fiberglass braided one-tenth number mm.Owing to glass tape is softer, therefore steel The fluctuatings of plate etc. will not be impacted, it is possible to closely sealed with the back side.When welding, immediate vicinity melts, but non-melt portion has and prevents The effect as cushion function of the excessive burn-off of root.It addition, between the contact chip corresponding with each electrode and steel plate The source of welding current of wiring independence.Being explained, the donor rollers of the surface that each welding wire is arranged at each contact chip delivers to welding Portion.

And, use the experimental provision shown in Fig. 6, in addition to a part (No.3-8 described later), carry out two electrode one sides and bury The test of arc welding method.More specifically, use the assay device shown in Fig. 6, each electrode is changed gage of wire, supplier of electricity The control of formula, external behavior, wire speed, welding current, arc voltage, confirm its impact.At the experimental provision shown in Fig. 6 In, the front end of the first welding wire 110 is set to 70mm with the interelectrode distance of the front end of the second welding wire 120.And, the welding in this example Although speed is constant under each manufacturing condition, but different according to the difference of manufacturing condition.It is explained, No.3-8 In for test based on the single electrode one side submerged-arc welding method only using the first welding wire 110.

As result of the test, have rated root pass shape, table weld bead shape, internal flaw.With regard to root pass shape Speech, with width as 6mm more than, root height as 1mm more than and below 4mm ideal, and will offset little, the deviation of width Little situation is set to be the most well A, some these is evaluated poor but arrive the situation of the degree needing correction and be set to B, Root pass shape defect need situation about revising be set to C the most defective.Table weld bead shape is also set and welds with root The metewand that road shape is same.For internal flaw, though will carry out ultrasonic test, section macroscopic view notch test also Do not observe that the situation of defect is set to "None", will confirm that the bad situation of fusion is set to " having ".

3rd embodiment and the manufacturing condition of the 3rd comparative example and result of the test are shown in table 5 and table 6.Here, shown in table 5 No.3-1～No.3-4 be the 3rd embodiment, No.3-5～No.3-14 shown in table 6 is the 3rd comparative example.

[table 5]

[table 6]

First, the 3rd embodiment is illustrated.

In No.3-1, first electrode use AC constant voltage characteristic fixed speed control, second electrode use always with The exchange droop characteristic voltage FB speed Control come, obtains good root pass shape and table weld bead shape.

No.3-2 for being set to direct current constant current characteristics voltage FB speed change compared with No.3-1 by the second electrode Situation about controlling.Compared with being set to direct current with by the second electrode, it is set to during exchange to make root pass shape originally as No.3-1 The stability of shape is more excellent, here, by using groove packing material 600, so that this impact less feed through to root Weld bead shape.On the other hand, in the case of two electrode methods, become the domination that the second electrode is table weld bead shape of final electrode Electrode, thus while in permissible range, but is susceptible to that electric arc is the most dry, the direct current of the impact of arc blow can make shape Bad stability.

In No.3-3, the first electrode, the second electrode all use constant voltage characteristic fixed speed control, and the first electrode is for handing over Stream, the second electrode are direct current.As it has been described above, the second electrode becomes the dominant pole of table weld bead shape, thus while allowing model In enclosing, but it is susceptible to that electric arc is the most dry, the direct current aspect of the impact of arc blow exchanges than the two poles of the earth as No.3-1 Shape stability is worse.

In No.3-4, two electrodes are all set to the general composition of AC constant voltage characteristic fixed speed control.Root is welded The supply of the welding wire that road shape impact is maximum controls to be constant speed, and the second electrode of disposable sheet weld bead shape is not by electric arc phase Mutually the exchange of the impact of dry, arc blow, therefore obtains surface back side quality the most excellent in the 3rd embodiment.

Then, the 3rd comparative example is illustrated.

No.3-5 is currently used typical case.The two poles of the earth all use exchange droop characteristic voltage FB speed Control.Although Internal flaw, table weld bead shape on the contrary do not have special problem, but speed Control is unsuitable for root weld, root pass shape The worst.It addition, compared with above-mentioned first embodiment, the second embodiment, the thickness of slab of steel plate is less, therefore root pass shape Bad table weld bead shape is also had an impact of shape and make it be deteriorated.

In No.3-6, the first combination of electrodes AC constant current characteristic fixed speed control, do not carry out in this combination The Stabilization Control of welding arc length, therefore welds instability, not only produces the bad of root pass shape, and due to based on the The bonding layer of one electrode is the most unstable, thus bad also producing fusion with the junction portion of the second electrode.If picture first embodiment, Second embodiment makes electrodeplate become many like that, then root pass shape based on the first electrode is bad less to table welding bead shape Shape produces impact, but owing to this example is two electrode constructions, therefore table weld bead shape is brought by the instability of root pass shape Affect and cause it and be deteriorated.

In No.3-7, constant voltage this combination of characteristic fixed speed control of the first electrode in scope of the invention, but Gage of wire is relatively thin and reaches 2.0mm.Result: cannot form root pass, the rear side at steel plate produces depression.In order to be formed Root pass, needs take into account stronger arc force and reduce it without the thickness of the fusion pool of impact.In order to be adapted to this combination, Effectively making electric current density diminish, gage of wire is the biggest more favourable.That is, gage of wire be 2.0mm be inadequate.

In No.3-8, constant voltage this combination of characteristic fixed speed control at the category of invention, but only with an electricity Pole completes root pass simultaneously and is formed and the formation of table welding bead, is that tool is challenging.But, although root pass can obtain well Shape, but table weld bead shape cannot be made good.Owing to being formed specific to the effect that root pass is the first electrode, therefore Welding conditions is the most unrestricted, and table weld bead shape is had to the convex becoming narrow width.If more than two electrodes, then it is used for The welding condition that table weld bead shape is good is made, it is possible to formed at leading electrode at rear row electrode (especially final electrode) Thin and protruding fusion pool shape is repaired, and cannot share this effect, be therefore unsuitable for root weld in an electrode construction.

In No.3-9, leading electrode uses AC constant current characteristic voltage FB speed Control.Lack although internal Fall into, table weld bead shape does not on the contrary have special problem, but speed Control is unsuitable for root weld, and root pass shape is the most not Good.

The leading electrode of No.3-10, the rear row electrode of No.3-11, No.3-12 are set to constant voltage characteristic voltage FB speed Control, either direct current still exchanges, and for constant voltage characteristic, relative to the variation of welding arc length, voltage is not How changing, therefore the feedback control of monitoring voltage is low as the performance of welding arc length control device, thus welding instability, root Portion's weld bead shape, table weld bead shape all produce bad order, also produce fusion in junction portion bad.

The rear row electrode of No.3-13, No.3-14 is set to constant current characteristic fixed speed control, but whether direct current is also Being exchange, all do not carry out the Stabilization Control of welding arc length in this combination, therefore weld instability, root pass shape, table weld Road shape all produces bad order, also produces fusion in junction portion bad.

It is explained, in the first embodiment, to four electrode one side submerged-arc weldings use liner solder flux 401 and liner copper coin 402 are illustrated as the situation of cushion part 400.It addition, in a second embodiment, use in three electrode one side submerged-arc weldings Lower surfacing agent 411, liner solder flux 412 and air hose 413 are illustrated as the situation of cushion part 400.And then, the 3rd In embodiment, soft liner material 421 is used to be illustrated as the situation of cushion part 400 in two electrode one side submerged-arc weldings. But, the quantity of the electrode of multi-electrode one side submerged-arc welding and the composition of cushion part 400 are not limited to combinations of the above, can be to this Combination suitably changes.

Symbol description

1 ... welder, 10 ... the first welding unit, 11 ... the first feedway, 12 ... first source of welding current, 20 ... Two welding units, 21 ... the second feedway, 22 ... second source of welding current, 30 ... the 3rd welding unit, 31 ... the 3rd supply dress Put, 32 ... the 3rd source of welding current, 40 ... the 4th welding unit, 41 ... the 4th feedway, 42 ... the 4th source of welding current, 50 ... platform Car driving means, 60 ... control device, 70 ... the first welding flux feeding device, 80 ... the second welding flux feeding device, 90 ... chassis, 110 ... the first welding wire, 120 ... the second welding wire, 130 ... the 3rd welding wire, 140 ... the 4th welding wire, 200 ... workpiece, 201 ... the first steel Plate, 202 ... the second steel plate, 300 ... table solder flux, 400 ... cushion part, 500 ... welding metal, 600 ... groove packing material.

Claims

1. a multi-electrode one side submerged-arc welding method, it is characterised in that be the use of leading electrode and after this leading electrode The multi-electrode one side submerged-arc welding method of row electrode,

The welding wire of more than diameter 2.4mm is used respectively in described leading electrode and described rear row electrode,

Speed control to the power supply mode of the power supply that each welding wire is powered and external behavior with the feed speed of each welding wire Mode processed is as follows:

Described leading electrode is set to described power supply mode be exchange, described external behavior be constant voltage characteristic, described Speed control method is constant speed control,

In the rear row electrode is set to following in any one, i.e.

(a) described power supply mode be direct current, described external behavior be constant voltage characteristic, described speed control method be constant speed Degree controls,

B () described power supply mode is exchange, described external behavior is constant voltage characteristic, described speed control method is constant speed Degree controls,

C () described power supply mode is exchange, described external behavior is constant current characteristic, described speed control method is based on electricity The Voltage Feedback of arc voltage controls,

D () described power supply mode is exchange, described external behavior is droop characteristic, described speed control method is based on electric arc electricity The Voltage Feedback of pressure controls, and

(e) described power supply mode be direct current, described external behavior be that constant current characteristic, described speed control method are for based on electricity The Voltage Feedback of arc voltage controls.

Multi-electrode one side submerged-arc welding method the most according to claim 1, it is characterised in that described rear row electrode package is containing continuing institute State multiple electrodes of leading electrode and constitute,

Respectively by described power supply mode, described external behavior and described speed in the plurality of electrode constituting described rear row electrode Degree control mode is set as any one in described (a)～described (e).

Multi-electrode one side submerged-arc welding method the most according to claim 2, it is characterised in that constituting described rear row electrode In the plurality of electrode, from the point of view of described leading electrode, it is positioned at the final electrode of rear side by described power supply mode, described outside Characteristic and described speed control method are set as described (c) or described (d).

4. according to the multi-electrode one side submerged-arc welding method according to any one of claims 1 to 3, it is characterised in that make apparatus In the case of having the described power supply of described constant voltage characteristic, the slope of the voltage versus current in operating point i.e. differential value dV/ DI is-12.0 × 10^-3(V/A) more than.

Multi-electrode one side submerged-arc welding method the most according to claim 1, it is characterised in that there is described constant electricity in use In the case of the described power supply of properties of flow or described droop characteristic, the slope of the voltage versus current in operating point i.e. differential value DV/dI is-24.0 × 10^-3(V/A) below.

6. the manufacture method welding thing, it is characterised in that by employing leading electrode and after this leading electrode The manufacture method of the welding thing that mother metal is welded by the one side submerged-arc welding of row electrode,

The welding wire of a diameter of more than 2.4mm is used respectively in described leading electrode and described rear row electrode,

In the rear row electrode is set to following any one, i.e.