JP2849243B2 - Non-consumable nozzle type two electrode electroslag welding method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-consumable nozzle type electroslag welding method in which a groove surrounded by a metal and a base material is electroslag welded with two electrodes.

[0002]

2. Description of the Related Art Electroslag welding is widely used as a vertical automatic welding method. In particular, a welding nozzle type electroslag welding is used as a simple electroslag welding method for welding a diaphragm blind portion of a steel box column used for a building such as a building, or disclosed in, for example, JP-A-57-156883. Non-consumable nozzle electroslag welding, such as, is commonly employed.

[0003]

On the other hand, with the recent increase in the height of buildings such as buildings, the thickness of the steel material of the box columns used is extremely thick steel of 60 to 100 mm. In the above-mentioned consumable nozzle type electroslag welding and non-consumable nozzle type electroslag welding, welding can only be performed up to a plate thickness of about 60 mm. A fusion zone occurs. For example, FIG.
The space (groove) surrounded by the side plate 1, the diaphragm 2 and the abutments 3 and 4 shown in FIG.
As shown in FIG. 7A, when the nozzle 80 is oscillated and welded, an unmelted portion is generated at a location indicated by a black triangle in FIG. 7A.

[0004] Therefore, in the case of extremely thick steel, the groove is welded by two electroslag welding machines. However, since the nozzles of separate welding machines are inserted into the same groove, it takes a long time to prepare for welding and also requires welding. Time control also involves operating each of the two operation panels individually. Further, the penetration of the welding may be large at both ends of the groove, and may cause an unmelted portion at the center. For example, when two nozzles 80 and 90 are inserted into a groove as shown in FIG. 7B and welded simultaneously while stopping them, a black semicircle shown in FIG. In some places, unmelted portions may occur.

An object of the present invention is to make the penetration of electroslag welding of a large thickness such as extremely thick steel uniform without welding defects.

[0006]

SUMMARY OF THE INVENTION The present invention relates to
A non-consumable nozzle type two-electrode electroslag in which a groove surrounded by a surface along the X direction and a surface along the Y direction of the base material (1, 2) is simultaneously welded with two electrodes inserted side by side in the Y direction. in welding, the feed nozzle of the second electrode (80,9
0) were simultaneously swinging in the same direction in their arrangement direction, Y direction
Energy in the vicinity of the tip of the open direction and the center of the groove in the Y direction.
And the current energy Wh at the time of stopping the open end portion and the current energy Wc at the time of stopping near the center of the groove, Wc <Wm <Wh
Further, the power supply nozzles (80, 90) are pulled up so as to maintain the welding wire protrusion length (L) at which the welding current reaches the target current value. The symbols in parentheses indicate corresponding elements shown in the drawings.

[0007]

The operation will be described below with reference to the drawings and the like. FIG. 2 shows an overall outline of one electroslag welding machine used to carry out the present invention, FIG. 3 shows a front view of a stand of the welding machine, FIG. 4 shows a cross section taken along line 4a-4a in FIG. FIG. 5 is an enlarged cross section taken along line 5a-5a of FIG. 3, and FIG.
Fig. 6 shows a cross section taken along line a-6a. First, the structure of the welding machine will be described with reference to these drawings. The clamper 11 placed on the upper end surface of the side plate 1 (FIG. 3), which is one of the base materials, has a U-shaped cross section, Similar to the force, one leg of the U-shape has a screw 12 (FIG. 4) with a lever rod. Clamper 11
Is the side plate 1 in the form of receiving the side plate 1 between the U-shaped legs.
And fixed to the side plate 1 by tightening the screw 12. A swing mechanism 20 is mounted on the clamper 11 via a position adjustment mechanism 10 in the X direction (horizontal direction orthogonal to the longitudinal direction Y of the side plate 1) Tx1 (FIG. 2). Tx
The adjustment screw 13 (FIG. 3) of the one-way position adjustment mechanism 10
4) extends in the Tx1 direction and is rotatably fixed to the clamper 11. A nut (not shown) screwed to the adjusting screw 13 is fixed to a base 21 engaged with a rail (not shown) on the clamper 11 extending in the Tx1 direction.
When the adjusting screw 13 is turned clockwise (FIG. 3), the base 21 is rotated.
Moves to the right in FIG. 4, and when turned counterclockwise, the base 21 moves to the left.

The base 21 of the swing mechanism 20 has the above-mentioned T
Two guide rails 22 and 23 (FIG. 5) extending in the Y direction orthogonal to the x1 (X) direction and the height direction Z are fixed, and a carriage 28 is mounted on these rails 22 and 23.
It is mounted movably in the Y direction. A rack 37 extending in the Y direction is fixed to the carriage 28, and a pinion 36 meshes with the rack 37. Pinion 3
6 is an output shaft 35 of the speed reducer 33 fixed to the base 21.
It is stuck to. An input shaft (not shown) of the speed reducer 33 is driven to rotate by an electric motor 34. When the electric motor 34 rotates forward, the pinion 36 rotates forward and the carriage 28 moves rightward in FIG. 3, and when the electric motor 34 rotates reversely, the pinion 36 rotates reversely and the carriage 28 moves leftward. I do.

A screw rod 24 (FIGS. 5 and 6) extending in the Y direction and having knobs 25 and 26 is rotatably mounted on the base 21, and a guide bar 27 is provided in parallel with the screw rod 24. Extends and is fixed to the base 21. Screw rod 24
Has a right-hand thread in the first half, a left-hand thread in the second half, and a first magnet 31 in the first half.
The support of FIG. 6 is screwed into the second half with the support of the second magnet 32.
At 7, it is movably supported in the Y direction. First magnet 31
And the second magnet 32 are provided for defining the left and right turning points of the swing of the carriage 28 in the Y direction. One magnetic sensor (not shown) is provided on the upper end surface of the carriage 28. When an electric circuit (not shown) detects the magnetism of the first magnet 31, the electric motor 3
4 is stopped, and the electric motor 34 is turned forward.
When the magnetic sensor detects the magnetism of the second magnet 32, the electric motor
The energization of the motor 34 is stopped and the electric motor 34 is reversely energized. Thereby, the carriage 28 reciprocates (oscillates) in the Y direction. The width of this swing is increased or decreased by turning the knobs 25 and 26 to increase or decrease the distance between the first magnet 31 and the second magnet 32. That is, the swing width of the carriage 28 in the Y direction (this is the swing width of the power supply nozzles 80 and 90 in the Y direction) can be adjusted by turning the screw rod 24.

The carriage 28 is provided with a stand base 29 vertically (Z direction).
9 is inserted into the lower opening of the main trunk 41 of the stand. That is, the stand main body 41 is erected perpendicularly to the carriage 28 and can rotate about the Z axis. This rotation direction is indicated by an arrow Rz1 in FIG. A vertical groove 43 is cut at the lower end of the main stand 41, and two protrusions having an Ω-shaped cross section are formed so as to compress or expand the lower end. One protrusion is formed by a lock lever 44. The screw to which is fixed penetrates and is screwed to another projection. Lever 44
When the is rotated clockwise, the Ω-shaped opening is narrowed, and the main trunk 41 is tightened to the stand root 29, so that the main trunk 41 cannot rotate (Rz1). When the lever 44 is turned counterclockwise, the Ω-shaped opening widens and the main trunk
1 can be rotated (Rz1). This stand master 41
Further, an arm 58 is supported via a vertical and horizontal slide mechanism 50 (FIGS. 3 and 2).

The cross section of the vertical and horizontal slide mechanism 50 is Ω.
The main slide 41 penetrates the circular space of the Z-axis slider 51 (FIG. 3). A screw fixing a lock lever 54 similar to the lock lever 44 passes through one of the two Ω-shaped protrusions of the slider 51 and is screwed to the other. There is a pinion 53 between both projections, and this pinion 5
A knob 52 for adjusting the Z-direction position is integrated with 3 and these are rotatably supported by both projections. A rack 45 is fixed to the main trunk 41, and a pinion 53 is engaged with the rack 45. When the lock lever 54 is turned counterclockwise, the slider 51 can move up and down in the Z direction. Therefore, the knob 52 is turned to adjust the position of the slider 51 (arm 58) in the vertical direction Tz1 (FIG. 2). And
By turning the lever 54 clockwise, the slider 51 is locked. The Z-axis slider 51 has a Y-axis slider 55 (FIG. 1).
The arm 58 penetrates through the slider 55. The Y-axis slider 55 is also provided with a Y-direction position adjustment knob 56 similar to the Z-direction position adjustment knob 52,
A lock lever 57 (FIG. 4) similar to the lock lever 54 and a pinion similar to the pinion 53 are provided, and an arm 58 is provided with a rack similar to the rack 45.
Thus, the position of the arm 58 (the power supply nozzles 80 and 90) in the Y direction Ty2 (FIG. 2) can be adjusted. Arm 58
At the right end of (FIG. 1), a pull-up and interval adjusting mechanism 60 (FIGS. 1 and 5) is mounted.

The first support plate 62 of the lifting and spacing adjustment mechanism 60 is rotatably connected to a pin 61 fixed to the right end of the arm 58 and extending in the X direction. (FIG. 2). First support plate 62
A base of a ball joint 63A is fixed to the shaft, and a tip of an angle adjusting screw 64A is rotatably connected to a connecting rod integral with the ball of the ball joint 63A. The screw stem of the angle adjusting screw 64A is screwed into and penetrates a nut (not shown), and the nut is fixed to the right end of the arm 58. When the adjusting screw 64A is turned clockwise, the screw 64A moves rightward in FIG. 3 and pushes the first support plate 62 rightward (FIG. 3) via the ball joint 63A. The support plate 62 rotates around the pin 61 in the counterclockwise direction in FIG. When the adjusting screw 64A is turned counterclockwise, the screw 64A moves to the left in FIG. 3, which pulls the first support plate 62 to the left (FIG. 3) via the ball joint 63A. One support plate 62 rotates clockwise around the pin 61 in FIG. The angle (R) of the first support plate 62 (the feed nozzles 80 and 90 supported thereby) with respect to the vertical line is
x1) can be adjusted. The first support plate 62 has three guide rods 63 to 65 (FIG. 3) penetrating the second support plate 66.
4) is fixed at one end, and the other end of the
7 (FIG. 3) is fixed. A spacing adjusting screw 68 is rotatably connected to the opposing plate 67 but is integrally connected in the Y direction. The adjusting screw is screwed to the second support plate 66. The second support plate 66 is Y-shaped with guide rods 63 to 65.
The distance adjustment screw 6 is guided
Turning clockwise 8 moves the second support plate 66 to the right in FIG. 3 (the power supply nozzle 90 moves to the right to widen the interval between 80 and 90). When the interval adjusting screw 68 is turned counterclockwise, the second support plate 66 moves to the left in FIG. 3 (the power supply nozzle 90 moves to the left, and the interval between 80 and 90 becomes narrower).
Thus, the position of the second support plate 66 in the Y direction Ty3 (FIG. 2) with respect to the first support plate 62 (the distance in the Y direction of the power supply nozzle 90 with respect to the power supply nozzle 80) can be adjusted by the spacing adjustment screw 68. A speed reducer 69d is fixed to the first support plate 62, and its output shaft 69 passes through the first support plate 62 and the second support plate 66. The rotation shaft of the electric motor 69m is connected to the input shaft of the speed reducer 69. A first drive roller 71 is fixed to the output shaft 69. A key groove extending in the direction Y in which the shaft 69 extends is cut on the side peripheral surface of the output shaft 69, and the output shaft 69 is moved to the second position where the key groove is present.
It passes through the driving roller 91. Since the second drive roller 91 has a key protruding from the key groove, it slides in the longitudinal direction Y with respect to the output shaft 69 but is mechanically connected in the rotational direction. As a result, when the motor 69m rotates forward,
Both the first and second drive rollers rotate forward (this causes the power supply nozzles 80 and 90 to rise at the same speed: Tz in FIG. 2).
2).

On the first support plate 62, a pin 72 (FIG. 4) is rotatably erected, and a first rotating arm 73 is fixed to the pin 72. At a substantially intermediate portion of the first rotating arm 73, a first driven roller is opposed to the first driving roller 71.
LA 75 is mounted. In FIG. 4, a screw rod 84 extending in the direction of the upper end of the first rotating arm 73 penetrates.
One end of the screw rod 84 is rotatably connected to the first support plate 62 with a pin 83. The other end of the threaded rod 84 penetrating the spring seat and the compression coil spring 85 is provided with an adjusting nut 8.
4 is screwed. When the screw 86 is tightened, the first rotating arm 73 is pushed so as to rotate counterclockwise through the compression coil spring 85 and the spring seat, and the first power supply nozzle 80 is driven by the first driving roller. Press on 71. First
A pin 78 is rotatably erected on the support plate, and an eccentric cam 79 having a lever 81 is fixed to the pin 78. When the lever 81 is turned counterclockwise by 90 degrees, the eccentric cam 79 turns the first turning arm 73 back and forth 15 degrees clockwise against the repulsive force of the compression coil spring 85. , The driven roller 75 is the first power supply nozzle 80
Move away from On the first support plate 62, two roller shafts are set up, and driven rollers 76 and 77 are rotatably mounted on these roller shafts, and these driven rollers 76 and 77 are rotatably mounted. 7
At 7, the first power supply nozzle 80 is guided movably in the vertical direction Z. The gap between the driven rollers 76 and 77 can be adjusted with the adjusting screw 82.

The above-described first drive roller 71 and first drive arm
A second power supply nozzle pulling mechanism having the same structure as the first power supply nozzle pulling mechanism, which is a combination of the system 73, the first driven roller 75, and the like, is provided on the second support plate 66 (FIG. 3). The driven roller 9 which supports the second power supply nozzle 90 and is similar to the driven rollers 76 and 77 and the adjusting screw 82 described above.
6, adjustment screws 102 are mounted on the second support plate 66, and these guide the second power supply nozzle 90 movably in the vertical direction Z.

In the electroslag welding machine described above, the space between the first power supply nozzle 80 and the second power supply nozzle 90 is adjusted by the space adjustment screw 68 (FIG. 3) in a state of being mounted on the side plate 1 as shown in FIG. Can be adjusted (in the Ty3 direction). With the angle adjusting screw 64A (FIG. 3), the power supply nozzle 80,
90 is adjusted in parallel with the gold 3, 4 (Fig. 2) (Rx1 direction)
can do. In addition, a knob 5 for adjusting the position in the Y direction
6, the positions of the power supply nozzles 80 and 90 in the Y direction are adjusted (Ty
Knob for adjusting the position in the Z direction 5
2, the height of the feeding nozzle pulling mechanism such as the first support plate 62 (T
z1 direction) can be adjusted. Further, the lock lever 44 (FIG. 3) is loosened and the main trunk 41 is rotated with respect to the carriage 28 to adjust the plane including both the power supply nozzles 80 and 90 parallel to the vertical plane of the side plate 1 (Rz1 direction). The position of the power supply nozzles 80 and 90 in the X direction can be adjusted (Tx1 direction) with the adjustment screw 13. In addition, turning the knobs 25 and 26 to feed the power supply nozzles 80 and 9
The swing width in the Y direction (Ty1) of 0 can be adjusted.

Wire feeding devices 112 and 122 (FIG. 2) are attached to the power feeding nozzles 80 and 90, respectively.
Unwinds and feeds the welding wire wound on the side plate 1
Between the power supply nozzles 80 and 90 and the welding power supply 11
4, 124 (FIG. 2) supply the welding current. Welding current,
The voltage value, the swing speed and the pulling speed of the power supply nozzles 80 and 90 are set on the operation panel 115.

First, a plate thickness t1 = t2 shown in FIG.
= 100 mm, gap G = 25 mm
Non-consumable electroslag welding was performed under various conditions, and the presence or absence of penetration and defects was examined by macro sectional inspection. FIG.
FIG . 1B shows a cross-sectional view taken along the line 1b-1b in FIG . 1
25 is a slag, 126 is a molten metal, 127 is a weld metal, and the penetration region is in the range of 126,127.

As shown in FIG. 7A, in the case of welding by swinging one power supply nozzle 80, the swinging movement from one end (solid line) to the other end (dashed line) and vice versa. While doing
The molten slag at the open end (the surface of the gold 4 and the surface of the gold 3) begins to solidify, making the arc at the open end unstable.
An unmelted portion (black triangle) was formed at the open tip.

As shown in FIG. 7 (b), when the two power supply nozzles 80 and 90 are inserted into the groove and welding is performed so that they are not oscillated, the nozzle does not oscillate. An unmelted portion (a black semicircle ) was formed at the center of the groove, particularly near the welding start portion.

As shown in FIG. 7C, when the two power supply nozzles 80 and 90 are continuously oscillated and the welding current and the voltage are set to a predetermined condition and the welding is performed, the open end portion (the contact metal 4) is used. The current energy (product of welding current and voltage) at the surface and the surface of the metal 3 is low, the penetration at the open end is small, and the range of welding conditions is narrow. Further, since the penetration amount at the central portion of the groove is large and the cooling rate at the central portion of the weld metal is slow, the crystal grains become large, and the toughness particularly at the central portion of the weld metal is deteriorated.

FIG. 7D shows that two power supply nozzles 80 and 90 are connected to the open front end (the surface of the contact 4) by the method of the present invention.
Penetration (12) when welding is performed by swinging while temporarily stopping at the turning point near the surface of the metal 3 and at the center of the groove.
7) is shown. The penetration at the open tip is sufficient, and the penetration amount near the center is also appropriate. In this case, as welding conditions, current energy Wm at the time of nozzle swing and current energy Wh at the time of stopping at the turning point near the open front end,
Current energy Wc when paused at the center of the groove
Needs to satisfy Wc <Wm <Wh. Wm =
If Wc or Wm <Wc, the penetration amount in the central portion of the weld metal is large, and the cooling rate in the central portion of the weld metal becomes slow, so that the crystal grains become large, and the toughness particularly in the central portion of the weld metal deteriorates. If Wm = Wh or Wm> Wh,
If the amount of penetration at the open tip is small, especially if Wm> Wh, an unmelted portion will be formed at the open tip. In the present invention, the power supply nozzles 80 and 90 are simultaneously swung in the same direction and are temporarily stopped near the turning point near the open front end and near the swing center point. When the nozzles 80 and 90 approach relatively at the time point and swing relatively away at another time point, the penetration amount in the central portion of the groove increases even if Wc <Wm, and the central portion of the weld metal Since the cooling rate of the metal becomes slow, the crystal grains become large, and the toughness particularly at the central portion of the weld metal deteriorates.

In the welding of the present invention, one power supply nozzle 80
Is stopped at the left turn, its current energy is W
h, the other power supply nozzle 90 is stopped near the center (the left turning point of the nozzle 90), and its current energy is Wc. While one of the nozzles 80 is moving from the left turning point to the vicinity of the center (the right turning point of the nozzle 80),
The other power supply nozzle 90 moves from the vicinity of the center toward the right turn point, and the current energy of both power supply nozzles 80 and 90 is Wm. When one power supply nozzle 80 stops near the center (right turn point), its current energy is Wc, and the other power supply nozzle 90 stops at the right turn point and its current energy is Wh. While one of the nozzles 80 is moving from the vicinity of the center (right turn point) to the left turn point, the other power supply nozzle 90 is moving from the right turn point to the vicinity of the center part (left turn point),
The current energy of both power supply nozzles 80 and 90 is Wm.
As described above, according to the present invention, the two power supply nozzles 80 and 90 are swung synchronously in the same direction, temporarily stopped at the turning point, and
The welding conditions such that c <Wm <Wh are determined so as to obtain sufficient penetration at the open end and avoid excessive penetration at the center of the groove. In addition, Wm of both power supply nozzles 80 and 90 is the same,
It is preferable that Wm be the same and Wh be the same, since uniform penetration can be obtained over the entire groove.

Next, the raising of the power supply nozzles 80 and 90 is as follows.
The welding current is detected and controlled so that it becomes the target current value. As the welding proceeds, the level of the molten metal rises, and this rise shortens the wire projection length L (FIG. 1b) and increases the welding current. The motor 69m (FIG. 3) is urged forward so that the welding current becomes the target value.
0 and 90 are pulled up. That is, the feeding nozzle 8 is set so that the wire protrusion length L becomes a value corresponding to the target current value.
0 and 90 are pulled up. The power supply nozzles 80 and 9
The swing width of 0, the distance between the nozzles, and the pause time during the swing may be appropriately selected and adjusted according to the groove size and other welding conditions, but the above-mentioned t1 = t2 = 100 m
When m and G = 25 mm, the swing width is preferably 10 to 40 mm, the distance between the nozzles is in a range where the nozzles do not contact the abutments 3 and 4 due to the swing, and the pause time is preferably 2 to 7 sec.

[0024]

EXAMPLES First, the thickness of the chemical components shown in Table 1 was 80 mm.
And 100 mm SM490B steel as shown in FIG. 2 was used as a material to be welded (side plate 1, diaphragm 2,
4), and the gap G of the groove was G = 25 mm. Groove depth (welding length = height of side plate 1: Tz2 direction in Fig. 2)
Is 750 mm.

[0025]

[Table 1]

Electroslag welding was performed on the groove with two electrodes using commercially available wires having the chemical components shown in Table 2 and the welding conditions shown in Table 3. The welding conditions were the same for both electrodes. Moreover, the slag bath depth in welding so that the 15 mm, welded Star - was charged medium manganese oxide based flux during slot. The wire protruding length L was within the range of L = 25 to 30 mm for both electrodes.

[0027]

[Table 2]

After welding, 100 m from the welding start
m, 100 from center of weld depth and weld crater
Macro test pieces were sampled from three places of mm, and the presence or absence of welding defects was examined. Further, an impact test piece of JISZ3111 No. 4 was sampled from the center of the weld metal of the test plate having no defect, and the test was conducted. Table 3 shows the results.

[0029]

[Table 3]

As a result, the results of Experiment No. 1
Nos. 3 to 3 had uniform penetration, as shown in FIG. 7 (d), had no welding defects, and also satisfied the toughness of the central portion of the weld metal. In the comparative examples, Experiment Nos. Reference numeral 4 denotes a nozzle position H (a turning point on the coin side of the swing), M (moving area), and C
Since the current energy at (the return point near the center of the swing) is Wh = Wm = Wc (= 16650), the penetration at the open tip is small and the penetration at the center of the groove is too large. As shown in FIG. 7 (a), the crystal grains at the center of the weld metal became large and the toughness was slightly poor. Experiment N
o. In Fig. 5, since the nozzle was not swung, the molten pool was divided into right and left, as shown in Fig. 7 (b), and the center of the groove in the macro section at 100mm from the welding start portion. An unmelted portion was formed in. Experiment No. In No. 6, since the current energy at the nozzle positions H, M, and C is Wh <Wm <Wc, the current energy is as shown in FIG. The penetration at the center of the groove was too large.

[0031]

As described above, according to the method of the present invention, the electroslag welding of an extremely thick steel is performed simply and uniformly, and welding with no defects and excellent toughness is realized. Therefore, the industrial utility value of the present invention is high.

[Brief description of the drawings]

1A is a side plate 1 and a diaphragm 2 shown in FIG.
And enlarged plan views of the golds 3 and 4, (b) is 1b of (a)
FIG. 2 is a sectional view taken along line -1b.

FIG. 2 is a perspective view showing an outline of one electroslag welding machine embodying the present invention.

FIG. 3 is an enlarged front view of the electroslag welding machine shown in FIG.

FIG. 4 is a sectional view taken along line 4a-4a in FIG.

FIG. 5 is an enlarged sectional view taken along line 5a-5a in FIG. 3;

FIG. 6 is a sectional view taken along line 6a-6a in FIG.

FIG. 7 is a plan view showing a groove surrounded by a side plate, a diaphragm, and a metal plate for performing electroslag welding.

[Explanation of symbols]

1: side plate 2: diaphragm 3, 4: contact metal 10: position adjustment mechanism 11: clamper 12: screw 13: adjustment screw 20: swing mechanism 21: base 22, 23: guide rail 24: screw rod 25, 26: Knob 27: Guide bar 28: Carriage 29: Stand base 31, 32: Magnet 33: Reduction gear 34: Electric motor 35: Output shaft 36: Pinion 41: Stand main body 43: Vertical groove 44: Lock lever 45: Rack 50: Up / down, left / right slide mechanism 51: Z-axis slider 52: Knob 53: Pinion 54: Lock lever 55: Y-axis slider 56: Knob 57: Lock lever 58: Arm 60: Pull-up and spacing adjustment mechanism 61: Pin 62: first support plate 63A: ball joint 64A: angle adjusting screw 63: guide rod 64: guide rod 65 : Guide rod 66: Second support plate 67: Opposing plate 68: Spacing adjusting screw 69: Shaft 69 d: Reducer 69 m: Electric motor 71: First drive roller
72: pin 73: first rotating arm 75: first driven roller 76: driven roller 77: driven roller 78: pin 79: eccentric cam 80: first power supply nozzle 81: lever 82: adjusting screw 83: pin 84: screw rod 85: compression coil spring 86: screw 90: second power supply nozzle 91: second driving roller 96: driven roller 102: adjusting screw 111, 121: spool 112, 122: Wire feeding device 113,123: Relay member 114,124: Welding power supply 115: Operation panel 116,117: Welding wire 125: Slag 126: Molten metal 127: Weld metal t1: Side plate thickness t2: Diaphragm thickness (groove width) G: Gap L: Projection length of welding wire

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Shigeo Kamimae 7-6-1, Higashi Narashino, Narashino City, Chiba Prefecture Nippon Steel Welding Industry Co., Ltd. Equipment Division (56) References JP-A-52-31935 (JP, A) Fully open sho 59-153088 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B23K 25/00 B23K 9/00 501 B23K 9/022 B23K 9/12

Claims (1)

(57) [Claims] 1. A surface along the X direction of the metal and a Y direction of the base material .
Parallel to groove which is enclosed formed at a surface along, it in the Y direction
Non-consumable nozzle type 2 for simultaneous welding with all inserted 2 electrodes
In the electrode electroslag welding, the two feeding nozzle electrodes simultaneously swung in the same direction in their arrangement direction, open distal end and also the Y-direction in the Y direction
In the vicinity of the center of the groove, the current energy Wm when the power supply nozzle swings, and the current energy Wh when the front end of the groove stops.
And the current energy Wc when stopped near the center of the groove, W
A non-consumable nozzle type two-electrode electroslag welding method, characterized in that c <Wm <Wh, and furthermore, the power supply nozzle is pulled up so as to maintain a welding wire protrusion length at which a welding current reaches a target current value.