JP4434066B2 - Backing support device and arc welding device - Google Patents

Description

  The present invention relates to a backing support device that supports a backing material by supporting the backing material on the lower surface of a plate joint groove portion between steel plates to be welded on one side from below, and an arc welding apparatus using the same. This welding apparatus can be used for, for example, single-sided submerged arc welding of a relatively thick steel plate having a thickness of 10 mm to 35 mm, and can also be used for single-side gas shield arc welding of a relatively thin steel plate having a thickness of 6 mm to 9 mm, for example.

  Conventionally, as a high-efficiency welding method for thick steel plates, a single-sided submerged arc welding method has been actively applied mainly to shipbuilding. Since the backing member of the single-sided submerged arc welding apparatus has a length of several tens of meters, a flux spreading / recovering vehicle is used to automate the flux spreading / recovering operation. After the backing member is lowered to the retracted position by the backing support device, the flux spreading / collecting vehicle runs on the backing member to eliminate residual flux and slag that have undergone the welding process. And new flux is spread | dispersed on the upper surface of a backing member. When spraying is finished, the flux spraying / collecting vehicle moves to the retracted position, and the backing support device drives the backing member upward to press the flux against the joint part of the jointed steel plate panel. Then, plate welding is started. When this welding is finished, the backing support device lowers the backing member to the retracted position. A flux spreading / collecting vehicle runs on the backing member to eliminate residual flux and slag.

JP-A-10-128542 JP 2004-122138 A Japanese Patent Laid-Open No. 6-254683 JP-A-8-99178 Japanese Patent Laid-Open No. 5-337651.

  Patent Document 1 describes a flux spraying / collecting device that travels on a backing copper plate and removes and collects residual flux and slag used for welding from the backing copper plate and spreads a new flux on the upper surface of the copper plate. Patent Document 2 describes a backing copper plate support device including a chain conveyor or a screw conveyor that supports a backing copper plate and discharges and conveys the flux that the flux spreading / collecting vehicle excludes from the backing copper plate. The conveyor is below the backing copper plate and extends in the longitudinal direction of the backing copper plate.

  In recent years, there has been an increasing demand for higher welding efficiency, and a technique has been developed that enables welding at a high speed of 100 cm / min or more using three or more electrodes using a flux as a backing. For example, in Patent Document 3, a direct current is passed through the first electrode to concentrate the arc as a low voltage, and the voltage of the second electrode is increased to form a stable and sound back bead. In Patent Document 4, the width and height of the back bead are limited by high-speed welding by limiting the wire diameter of each electrode, the welding current of the first electrode and the second electrode, the distance between the electrodes, the spreading thickness and bulk density of the backing flux. Has a stable and smooth back bead. Furthermore, Patent Document 5 provides a weld metal free from defects by limiting the wire diameter of each electrode, the welding current of each electrode, the distance between electrodes, the back flux component, the front flux component, and the C amount of the wire with four electrodes. There is a technical disclosure.

  Flux copper backed multi-electrode single-sided submerged arc (latent arc) welding is a fast and efficient welding method used in many shipyards. To increase the welding efficiency, 4.8mmφ is used for the welding wire. , Using a large diameter wire of 6.4 mmφ, and pressing the back flux spread about 5-6 mm on the backing copper plate from the back of the steel plate to reduce the unevenness of the back bead. However, if the thickness of the spread flux is thin, if the steel sheet is distorted by welding heat, the flux pressing force from the back side will be reduced, or in the worst case, a space will be generated directly under the groove, and the back bead can be formed. Disappear (dripping, dropping off, etc.).

Therefore, in thin plate welding with a thickness of 6 to 10 mm, steel plate distortion (bending) due to welding heat occurs, and good back bead formation cannot be achieved. Therefore, CO ₂ shielded arc welding is performed in thin plate welding. However, in gas shielded arc welding such as CO ₂ shielded arc welding, the apparatus becomes large and complicated, such as using a solid backing material for forming a back bead.

  By the way, in the arc welding equipment for supporting the lower surface of the groove with the flux-spreading back copper plate of the shipbuilding large plate joint, the welding length of the large plate is as long as 15 to 30 m. It becomes long with 33m. A backing device equipped with a backing copper plate x drive mechanism for aligning the backing copper plate with the groove in the groove width direction x is located at both ends of the backing copper plate. In order to align with the groove, the backing copper plate is driven in the x direction by a backing device provided with an x drive mechanism, but there are cases where the backing copper plate maintains a straight line and does not translate in the x direction.

  Conventionally, the movement of the backing device in the groove width direction x (left and right) has been done by pushing and pulling the backing copper plate with two left and right adjustment jack mechanisms near the end of the backing copper plate (near the end of the backing copper plate). Although it is aligned with the groove line, it is difficult to align the entire length of the groove line by deforming the backing copper plate into an arc shape. That is, if the backing device equipped with the x drive mechanism at both ends of the backing copper plate is simultaneously driven in the same direction, even if both ends of the backing copper plate are moved in the same direction by a predetermined amount, the intermediate point of the backing copper plate is moved. The amount may be small and adjustment of the misalignment of the midpoint may be necessary. If the groove is not parallel to the backing copper plate, the end of the backing copper plate is opened by driving the backing copper plate with the backing device equipped with an x drive mechanism only on one side or one side at a time. Adjust the attitude of the backing copper plate to match the first, but the backing copper plate keeps a straight line around the stationary side end of the backing copper plate and the driving side end does not turn, but the closer to the driving side end The required amount of x movement may not be obtained as the curve is greatly bent and closer to the stationary side end.

  In particular, as shown in FIG. 16, since the steel plate 5 to be welded has a different thickness and has a step on the lower surface, the back flux 5rf is grooved by matching the taper surface of the step with the side taper surface of the backing copper plate 21. In the case of arc welding in pressure contact with the lower surface, if the backing copper plate 21 is displaced in the x direction with respect to the groove of the steel plate 5, the back flux 5rf of the required thickness is not evenly pressed against the groove lower surface, It becomes non-uniform, and in the extreme case, it becomes a problem that the back bead is burned out.

  Therefore, it is necessary to accurately position the backing copper plate 21 with respect to the groove as shown in FIG. 16 over the entire length of the groove, but this position adjustment may require a great deal of labor.

  An object of the present invention is to facilitate the position adjustment in the groove width direction x of the backing material covering the entire length of the groove extending in the y direction.

(1) Backing material (21) extending in the horizontal y direction;
Three or more backing support devices (12-15) distributed in the horizontal y direction, each supporting the backing material (21) below, each having a backing material lifting mechanism and a backing material horizontal x drive mechanism; ,
The horizontal x drive mechanism (12M) of the support device (12) at one end in the y direction in the backing support device group is not driven and the horizontal x drive mechanism (15) of the support device (15) at the other end ( 15M), the backing material horizontal x drive mechanism (13M, 14M) of the support device (13, 14) between the support devices (12, 15) at both ends is supported by the support devices (13M, 14M) at both ends. 12,15) The ratio (L1 / (L1 + L2 + L3), (L1 + L2) / (L1 + L2 + L3)) of the distance (L1, L1 + L2) from the support device (12) of the one end to the y-direction distance (L1 + L2 + L3) A backing device comprising a backing material x-drive device (100) that is simultaneously driven at a product speed of a product of the drive speed of the support device (15) of the part.

  In addition, in order to make an understanding easy, the code | symbol of the response | compatibility of the Example shown to a drawing and mentioning later or an equivalent element is added for reference for an illustration. The same applies to the following.

  Since there are three or more backing support devices having the backing material horizontal x driving mechanism, the backing material can be x-driven not only at both ends of the backing material but also between both ends. Then, in order to align the other end with the groove x while the one end of the backing material is stationary, when the other end is driven x, the back of the support device between the support devices at both ends is provided. The horizontal x-drive mechanism of the material has a backing material at a speed of a product of the ratio of the distance from the support device at one end to the distance in the y direction between the support devices at both ends and the drive speed of the support device at the other end. Drive simultaneously. Thereby, the backing material keeps a straight line with the one end portion on the stationary side as the center, and the other end portion on the driving side turns. All of the backing support devices having x drive mechanisms other than the support device at one end on the stationary side simultaneously apply the backing material at a speed necessary for the backing material to maintain a straight line corresponding to each device position on the turning radius. Since it drives, the drive load added to each support apparatus is lighter than the case where each support apparatus is driven individually, and a backing material rotates smoothly, maintaining a straight line.

  (2) Each backing horizontal x drive mechanism includes each pulse generator (12R-15R) for generating x drive synchronization pulses; the x drive device (100) is for x drive synchronization generated by each pulse generator Means for detecting the frequency of the pulse (12F-15F), and the frequency obtained by multiplying the frequency of the x-drive synchronization pulse generated by the pulse generator of the support device (15) at the other end with the ratio; The frequency of the x drive synchronization pulse generated by the pulse generator of the backing material horizontal x drive mechanism (13M, 14M) of the support device (13, 14) between the support devices (12, 15) of And means (13vdb, 13vdt, 13D / 14vdb) for driving the backing material horizontal x drive mechanism (13M, 14M) of the support device (13, 14) between the support devices (12, 15) at both ends. , 14vdt, 14D); the backing device according to (1) above.

  (3) The x driving device (100) includes one end side indicating means (91b, 92b) for instructing x driving of the supporting device (12) at the one end and x driving of the supporting device (15) at the other end. The other end side indicating means (91t, 92t), and the one end supporting device (12b) and the both end supporting devices (12) according to the x drive instruction of the one end side indicating means (91b, 92b) ( 12, 15) is driven, and the other end support device (15) and the both ends are driven according to the x drive instruction of the other end side indicating means (91t, 92t). The support device (13, 14) between the support devices (12, 15) of the part; the backing device according to (1) or (2) above.

  (4) The one end side instructing means (91b, 92b) and the other end side instructing means (91t, 92t) respectively instruct one of the forward driving and the backward driving in the x direction; Backing device.

  (5) The x drive device (100) includes center arrangement instruction means (91b, 91t), and in response to the center arrangement instruction of the center arrangement instruction means (91b, 91t), the backing support device group Each supporting device is driven to the center in the x direction; the backing device according to any one of (1) to (4) above.

(6) The backing device (12-15, 100) according to any one of (1) to (5) above;
Welding trolley traveling in the horizontal y direction (3);
A welding head base (4) supported by a lifting mechanism (53) and a horizontal x driving mechanism (52) equipped in the welding carriage (3) and driven in the vertical z and horizontal x directions;
A groove detector (54, 55) supported by the welding head base (4); and
Based on the groove detection of the groove detectors (54, 55), the elevating mechanism (53) and the horizontal x drive mechanism (52) are driven so that the welding head base (4) is predetermined with respect to the groove. Scanning control means (90) for controlling the height and the horizontal x position;
An arc welding apparatus comprising:

  (7) In the welding head base (4), a filler spraying device (58), a gas shield arc welding torch holder (61), a surface flux spraying nozzle (70,75) for submerged arc welding, and a plurality of Submerged arc welding torches (71, 74, 76) are supported side by side in the horizontal y direction; a gas shielded arc welding torch (61) held by the gas shielded arc welding torch holder (61) on the welding carriage (3) 60) means for supplying a gas shielded arc welding wire (69), means for supplying flux to the surface flux spray nozzle (70, 75) (73), and the submerged arc welding torch (71, 74, 76) Means (72) for supplying a submerged arc welding wire to each of the arc welding apparatus according to (6).

  According to this, it is possible to perform submerged welding of relatively thick steel plates using a plurality of submerged arc welding torches (71, 74, 76), as well as gas shielded arc welding torch holders (61). Gas shield arc welding of a relatively thin steel sheet while holding the shield arc welding torch (60) can be alternatively performed, and any back welding can form a good back bead.

  (8) From the head in the welding head direction (y), the groove detector (54, 55), the filler spraying device (58), and the gas shield arc welding torch are held on the welding head base (4). The tool (61) and the surface flux spray nozzle (70,75) for submerged arc welding and a plurality of submerged arc welding torches (71,74,76) were arranged in this order; the arc according to (7) above Welding equipment.

  (9) A first front flux distribution nozzle (70) is provided immediately before the foremost first submerged arc welding torch (71) among the plurality of submerged arc welding torches (71, 74, 76). The first submerged arc welding torch (71) is followed by a second submerged arc welding torch (74), the second submerged arc welding torch (74) is followed by a second surface flux spray nozzle (75), There is a third submerged arc welding torch (76) after the two front flux spray nozzles (75); the arc welding apparatus according to (8) above.

  (10) The flux recovery means (77) supported by the welding head base (4) is located at the most downstream position with respect to the welding traveling direction (y); the arc according to (8) or (9) above Welding equipment.

  (11) The apparatus further includes a rocking device (63) supported by the welding head base, which supports the gas shield arc welding torch holder (61) and rocks in the groove width direction x. 7) thru | or the arc welding apparatus as described in any one of (10).

  (12) The backing support device (14: 21s to 27) includes an elevating frame (22) for supporting the backing material (21) and a driving means for driving the elevating frame upward; ), A plurality of support arms (24, 25) that extend in the horizontal x direction and project outward from both sides in the x direction in the space in which the elevating frame (22) moves up and down, and each of the support arms A plurality of driving means (26, 27) for driving the upper side of the arc welding device according to any one of (7) to (11).

  (13) A chain conveyor (28) extending in the y direction for collecting the flux dropped from the backing member (21) is installed below the elevating frame (22); the arc welding apparatus according to (12) .

  (14) The backing support device according to (12) or (13), wherein the driving means (26, 27) is a multi-stage hydraulic jack.

  Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.

  FIG. 1 shows a partial outline of a large plate welding facility equipped with one embodiment of the present invention. A gate-type carriage 2 is on a rail 1 extending in the horizontal x direction perpendicular to the paper surface of FIG. 1 and can travel on the rail 1 in the horizontal x direction. A welding cart 3 that travels in the horizontal y direction is attached to the beam extending in the horizontal y direction of the portal type cart 2, and the welding head base 4 is supported by the welding cart 3. The base 4 is equipped with a multi-electrode single-sided submerged arc welding apparatus and a single-sided gas shielded arc welding apparatus.

  A large plate 5 in which a plurality of steel plates are connected by tack welding is transported in the horizontal x direction at a height (z position) shown in FIG. In addition, the single-sided welding apparatus 4 is driven in the horizontal y direction (the direction opposite to the arrow y), and is welded between two steel plates connected by tack welding, distributed in the horizontal x direction, of the large plate 5. The part is subjected to submerged arc welding or gas shielded arc welding. At that time, the backing copper plate 21 rises in the upward direction z and is in pressure contact with the spliced welded portion on the back surface of the large plate 5 via the flux dispersed on the upper surface thereof.

  On the floor surface (pit bottom surface), a plurality of rails 6 to 9,... Extending in the horizontal x direction are laid over several tens of meters in the horizontal y direction. Is listed. A plurality of backing support devices 12 to 16,... Are assembled to the carriage 11.

  FIG. 2 shows the backing support device 15 in an enlarged manner. The carriage 11 has vertical blocks 42 and 43, and a large plate conveying rollers 44 and 45, and a lower support fixing roller 46 and a lower support lifting / lowering adjustment roller 47 for adjusting the height of the plate joint. The plate joint is located directly above the backing copper plate 21, and the left steel plate in FIG. 2 is supported by a roller 46 below the plate joint, but the right steel plate is left by adjusting the lifting and lowering of the roller 47. The same steel plate and height are aligned.

  In the blocks 42 and 43, the elevating frame 22 is guided so as to be movable up and down z. A backing copper plate carriage 23 rides on the upper surface of the lifting frame so as to be movable in the left-right direction x, and the backing copper plate 21 is on the carriage 23.

  The elevating frame 22 has arms 24 and 25 protruding left and right, and these arms 24 and 25 are supported below by two-stage hydraulic jacks 26 and 27. The hydraulic jacks 26 and 27 are supported below by the backing copper plate carriage 11. A chain conveyor 28 is provided below the space in which the elevating frame 22 moves up and down, and is supported by the backing copper plate carriage 11.

  The endless chains 30 and 31 of the chain conveyor 28 are stretched so as to mesh with the sprocket wheel 32 (FIG. 1). It is something that sticks out. The scraping leg of the upper chain 30 is in sliding contact with the groove plate 29 (FIG. 2) extending in the y direction, and when it moves in the y direction, it is excluded from the backing copper plate 21 and falls into the groove plate 29. Residual flux and slag after welding are conveyed in the y direction, dropped onto a belt conveyor 48 extending in the x direction shown in FIG. 1, and carried out in the x direction by the belt conveyor 48.

  Residual flux and slag after welding on the backing copper plate 21 are removed by the flux spreading / collecting vehicle 49 and dropped onto the chain conveyor 28, and a new flux is applied to the backing copper plate 21 for the next welding. When spraying, the backing copper plate 21 is placed at the lower retracted position (z position) indicated by the solid line in FIG. The backing copper plate 21 sprayed with the new flux for welding is injected into the two-stage cylinder type hydraulic jacks 26 and 27, and the piston rod is protruded so that the position shown by the two-dot chain line in FIG. z position). FIG. 3A shows a state in which the backing copper plate 21 in which the new flux is spread on the plate joint is pushed up.

  3rf shown in FIG. 3A is the back flux dispersed on the backing copper plate 21. The upper drive of the backing copper plate 21 by the hydraulic jacks 26 and 27 is stopped when the upper surface of the backing copper plate 21 is at a position about 2 cm below the lower surface of the large plate 5 that is the material to be welded. Next, high-pressure air is supplied to an air hose 21h diverted from a high-pressure water supply hose for fire fighting, and the hose 21h swells into a circular shape, whereby the copper plate support 21s is driven upward, and the backing copper plate 21 is removed. The back flux 5rf, which is driven upward and is spread on the backing copper plate 21 to a thickness of about 5 mm, is pressed against the lower surface of the large plate 5. In this state, a plurality of submerged arc welders or one gas shielded arc welder on the welding head base 4 welds the plate joint while running in the y direction. During welding, the cut wire 5cw is fed to the groove of the large plate 5, and at the time of submerged arc welding, as shown in FIG. Inside, the arc of the welding wire Ew melts the cut wire 5cw. In the case of gas shielded arc welding, the surface flux is not dispersed, and the molten pool is wrapped with the shielding gas blown from the welding torch. When the welding in the full length in the y direction is finished, the backing copper plate 21 is returned to the lower retracted position (z position) indicated by the solid line in FIG.

  Since the chain conveyor 28 is below the lifting frame 22 and separated from the lifting frame 22 and fixedly supported by the carriage 11, it does not become a load of the hydraulic jack that supports the lifting frame 22 below. Conventionally, since the hydraulic jack is placed below the chain conveyor or screw conveyor and the lifting frame 22 is driven upward, the depth from the lower surface of the large plate (the upper surface position of the backing copper plate during welding) to the lower bottom of the hydraulic jack ( A deep pit in which the backing copper plate carriage 11 is installed is necessary (z distance) is deep (long).

  However, as shown in FIG. 2, the support arms 24 and 25 are projected to the outside of both sides in the x direction of the space in which the elevating frame 22 moves up and down, and these support arms 24 and 25 are connected to the hydraulic jacks 26 of the two-stage cylinder type. 27, the depth (z distance) from the lower surface of the large plate 5 to the lower bottom of the hydraulic jacks 26, 27 is made shallower (shorter), and the required depth of the pit where the backing copper plate carriage 11 is installed Can be shallow. That is, a shallow pit can be equipped with a backing support device and a conveyor for discharging residual flux.

  FIG. 4 is an enlarged view around the lifting frame 22 of the backing support device 15 shown in FIG. An upper end of a hanging frame 23a is fixed to a backing copper plate carriage 23 that can move in the left-right direction x on the elevating frame 22, and a tip of a screw rod 15ms extending in the groove width direction x is attached to the lower end of the hanging frame 23a. Is fixed. The screw rod 15 ms is screw-coupled to a nut with external teeth of the x reciprocating mechanism 15G2. A drive gear meshes with the external teeth of the nut, and the drive gear is connected to the output shaft of the speed reducer 15G1. The rotation shaft of the electric motor 15M is connected to the input shaft of the speed reducer 15G1. A rotary encoder 22 is connected to the rotating shaft of the electric motor 15M, and the rotary encoder 15R generates one rotation synchronization pulse for each rotation of the rotating shaft of the electric motor 15M at a predetermined minute angle. When the electric motor 15M rotates forward, the screw rod 15ms is drawn out in the left (L) direction, and the backing copper plate carriage 23 moves in the left (L) direction (the direction opposite to the x arrow direction in FIG. 4). When the electric motor 15M rotates in the reverse direction, the screw rod 15ms is pulled in the right (R) direction, and the backing copper plate carriage 23 moves in the right (R) direction (the direction of the arrow x in FIG. 4).

  A center sensor 15SN, a left limit sensor 15SL, and a right limit sensor 15SR are disposed below the elevating frame 22, and the center sensor 15SN is a virtual opening in which the center position of the backing copper plate 21 in the x direction extends in the y direction. When it is at the same x position as the previous reference line, it detects the drooping frame 23a and outputs a high level H signal (groove center detection signal), and when it is outside the x position, it outputs a low level L signal.

  The x drive mechanism similar to the above x drive mechanism (combination of 23a, 15ms, 15G2, 15G1, 15M, 15R, 15SN, 15SL and 15SR) is the groove welding direction y of the backing copper plate 21 shown in FIG. The first backing support device 12, the fourth backing support device 13, the seventh backing support device 14, and the tenth backing support device 15 on the starting end side of FIG. The other No. 2, 3, 5, 6, 8, 9, and 11 support devices are not provided. The backing copper plate lifting mechanism is provided in all backing support devices.

  The arrangement intervals L1, L2, and L3 in the y direction shown in FIG. 1 of the backing support devices 12, 13, 14, and 15 provided with the x drive mechanism are the same in this embodiment. Conventionally, only the backing support devices 12 and 15 close to the both ends of the backing copper plate 21 are provided with the x drive mechanism, but in the present embodiment, they are divided into three equal positions. The fourth backing support device 13 and the seventh backing support device 14 are also provided with the above-described x drive mechanism.

  FIG. 5 shows an x position adjustment system for the backing copper plate that drives the electric motors 12M, 13M, 14M and 15M of the x drive mechanism of the backing support devices 12, 13, 14 and 15 equipped with the x drive mechanism. The center array indicating switch 91b and the left / right indicating switch 92b (one end side indicating means) shown in FIG. 5 are connected to the ground control panel on the y welding traveling start end side (left side in FIG. 1) of the welding equipment shown in FIG. Mobile) on the operation terminal. The center arrangement indicating switch 91t and the left / right indicating switch 92t (the other end indicating means) shown in FIG. 5 are connected to the ground control panel on the y-welding traveling end side (right side in FIG. 1) of the welding equipment shown in FIG. It is in the (mobile) operation terminal.

  The center arrangement instruction switches 91b and 91t are push switches (reset switches) for instructing the x position initialization of the backing copper plate, and close while the operation button is pressed, and automatically return to open when the pressing force is lost. . When the operator depresses and releases the operation button of the center array indicating switch 91b or 91t, a high level H pulse appears on the center array indicating line, and the electric motors 12M, 13M, 14M and 15M of the x drive mechanism are respectively turned on. It is given to each motor driver 12D to 15D to be driven. For example, in response to the H pulse, the motor driver 15D drives the electric motor 15M to rotate forward, and when the center sensor 15SN outputs a groove center detection signal (H), the motor driver 15D stops driving forward. When the center sensor 15SN does not output the groove center detection signal (H) and the left limit sensor 15SL outputs the signal H that detects the hanging frame 23a, the forward rotation driving is stopped there. Thereby, the center position in the x direction of the backing copper plate 21 at the y position of the support device 15 becomes the x position of the groove reference line. The other motor drivers 12D to 14D operate in the same manner, and the center position in the x direction of the backing copper plate 21 is adjusted to the x position of the groove reference line at each y position of the support devices 12 to 14.

  The left and right instruction switches 92b (one end side instruction means) and 92t (other end side instruction means) are normally open selection switches, and the operation lever is raised from the panel surface of the operation terminal (switch open). It can be tilted in the direction labeled L (left) and the direction labeled R (right) on the board. The operator uses the left / right instruction switch 92b to position the end of the backing copper plate 21 on the y welding travel start end side (left side in FIG. 1) of the welding equipment, that is, the start end in the x direction with respect to the groove reference line. Can be adjusted. Further, the position of the end of the backing copper plate 21 on the y-welding travel end side (right side in FIG. 1), that is, the end, of the backing copper plate 21 is adjusted in the x direction with respect to the groove reference line using the left / right instruction switch 92t it can.

  When the operator tilts the operation lever of the left / right instruction switch 92b to the L (left) side, a high level H (left drive instruction signal) is given to the motor driver 12D, and the motor driver 13D passes through the diode d6 and the left drive instruction line. And 14D. However, this H (left drive instruction signal) is interrupted by the diode d8 and is not given to the motor driver 15D. In response to the left drive instruction signal H, the motor driver 12D drives the electric motor 12M to rotate forward at a speed corresponding to the divided voltage of the resistors R1 and R2. The rotary encoder 12R generates an electric pulse by the rotation of the electric motor 12M, and the F / V converter 12F converts the frequency into a voltage level (frequency signal: speed signal). The motor driver 12D is configured so that the frequency of the electric pulse generated by the F / V converter 12F, that is, the rotation speed of the electric motor 12M matches the divided voltage level (target frequency signal: target speed signal) of the resistors R1 and R2. The electric motor 12M is accelerated or decelerated. As a result, while the left drive instruction signal H is present, the electric motor 12M rotates forward at a speed specified by the divided voltage levels of the resistors R1 and R2.

  The motor driver 13D has (L2 + L3) / (L1 + L2 + L3) of the voltage level (frequency signal: speed signal) generated by the F / V converter 12F, and L1 = L2 = L3, so that the voltage level of 2/3 is the target speed. As the (target frequency), the electric motor 13M is driven forward so that the rotation speed of the electric motor 13M (the output voltage of the F / V converter 13F) becomes the target speed. Note that the 2/3 voltage division is performed by a resistance voltage divider similar to the voltage divider by the resistors R1 and R2. The same is true for the 1/3 partial pressure.

  The motor driver 14D has (L3) / (L1 + L2 + L3) of the voltage level (frequency signal: speed signal) generated by the F / V converter 12F, and L1 = L2 = L3. As the (target frequency), the electric motor 14M is driven forward so that the rotation speed of the electric motor 14M (the output voltage of the F / V converter 14F) becomes the target speed.

  When the operator tilts the operation lever of the left / right instruction switch 92b to the R (right) side, a high level H (right drive instruction signal) is given to the motor driver 12D, and the motor driver 13D passes through the diode d5 and the right drive instruction line. And 14D. However, this H (right drive instruction signal) is also cut off by the diode d7 and is not given to the motor driver 15D. In this case, the motor driver 12D drives the electric motor 12M in reverse at a speed corresponding to the divided voltage of the resistors R1 and R2. The motor driver 13D drives the electric motor 13M in the reverse direction with a voltage level that is 2/3 of the speed signal generated by the F / V converter 12F as a target speed. The motor driver 14D drives the electric motor 14M in the reverse direction with 1/3 of the speed signal generated by the F / V converter 12F as a target speed.

  As described above, when the position of the starting end of the backing copper plate 21 is adjusted in the x direction with respect to the groove reference line using the left / right instruction switch 92b, the x drive on the starting end side of the backing copper plate 21 by the support device 12 is performed. The support device 13 drives the backing copper plate 21 in the same direction at a speed 2/3 of the speed, and the supporting device 14 drives the backing copper plate 21 in the same direction at a speed of 1/3. The supporting device 15 on the end side of the backing copper plate 21 does not drive the backing copper plate 21. Therefore, the backing copper plate 21 maintains the linearity in the y direction and the start end side pivots in the x direction. Since the three points in the y direction of the backing copper plate 21 are driven simultaneously, the driving load of each part is lower than in the case of single driving, and the backing copper plate 21 moves smoothly. The z position adjustment with respect to the groove reference line on the starting end side of the backing copper plate 21 is easy.

  When the operator tilts the operating lever of the left / right instruction switch 92t to the L (left) side, a high level H (left drive instruction signal) is given to the motor driver 15D, and the motor driver 13D passes through the diode d8 and the left drive instruction line. And 14D. However, this H (left drive instruction signal) is interrupted by the diode d6 and is not given to the motor driver 12D. In response to the left drive instruction signal H, the motor driver 15D drives the electric motor 15M to rotate forward at a speed corresponding to the divided voltage of the resistors R3 and R4. The rotary encoder 15R generates an electric pulse by the rotation of the electric motor 15M, and the F / V converter 15F converts the frequency into a rotation speed signal. The motor driver 15D increases or decreases the speed of the electric motor 15M so that the rotation speed of the electric motor 15M matches the target speed signal of the resistors R3 and R4. As a result, while the left drive instruction signal H is present, the electric motor 15M rotates forward at a speed specified by the divided voltage level of the resistors R3 and R4.

  Since the motor driver 13D has L1 / (L1 + L2 + L3) and L1 = L2 = L3 of the voltage level generated by the F / V converter 15F, the rotational speed of the electric motor 13M (1/3) is set to the target speed. The electric motor 13M is driven forward so that the output voltage of the F / V converter 13F becomes the target speed.

  Since the motor driver 14D has (L1 + L2) / (L1 + L2 + L3) and L1 = L2 = L3 of the voltage level (speed signal) generated by the F / V converter 12F, the voltage level of 2/3 is used as the target speed. The electric motor 14M is driven forward so that the rotational speed of the motor 14M (the output voltage of the F / V converter 14F) becomes the target speed.

  When the operator tilts the operation lever of the left / right instruction switch 92t to the R (right) side, a high level H (right drive instruction signal) is given to the motor driver 15D, and the motor driver 13D passes through the diode d7 and the right drive instruction line. And 14D. However, this H (right drive instruction signal) is also cut off by the diode d5 and is not given to the motor driver 12D. In this case, the motor driver 15D drives the electric motor 15M in the reverse direction at a speed corresponding to the divided voltage of the resistors R3 and R4. The motor driver 13D drives the electric motor 13M in the reverse direction with the voltage level of 1/3 of the speed signal generated by the F / V converter 12F as a target speed. The motor driver 14D drives the electric motor 14M in reverse by setting 2/3 of the speed signal generated by the F / V converter 12F as a target speed.

  As described above, when the position of the end of the backing copper plate 21 is adjusted in the x direction with respect to the groove reference line by using the left / right instruction switch 92t, the driving device 15 drives the end side of the backing copper plate 21 to x. The supporting device 13 drives the backing copper plate 21 in the same direction at a speed of 1/3 of the speed, and the supporting device 14 drives the backing copper plate 21 in the same direction at a speed of 2/3. The support device 12 on the starting end side of the backing copper plate 21 does not drive the backing copper plate 21. Therefore, the backing copper plate 21 maintains the linearity in the y direction, and the end side pivots in the x direction. Since the three points in the y direction of the backing copper plate 21 are driven simultaneously, the driving load of each part is lower than in the case of single driving, and the backing copper plate 21 moves smoothly. The z position adjustment with respect to the groove reference line on the end side of the backing copper plate 21 is easy.

  6 and 7 show a support structure for the welding head base 4. A vertical frame 50 hangs down from the welding carriage 3, and an elevating frame 51 is supported by the frame 50 so as to be movable up and down in the vertical direction z and is driven up and down in the vertical direction z by a lifting mechanism including a lifting motor 53. The A welding head base 4 is suspended and supported on the lift frame 51 so as to be horizontally movable in the horizontal direction x (FIG. 7), and a horizontal x drive mechanism 52 including a horizontal drive motor (not shown) on the lift frame 51 is shown. To drive in the horizontal direction x, that is, the direction across the groove (width direction of the groove).

  As shown in FIG. 8, the welding head base 4 includes a scanning roller 54 of the groove detector, a horizontal x direction (width direction of the groove) and a vertical z direction (depth direction of the groove) of the scanning roller 54. ) And a groove position sensor 55 that detects a deviation in the x and z positions of the groove, and a position adjustment in the x and z directions so as to support these and make the copying roller 54 the center of the width of the groove. There is a manual adjustment mechanism 56 (setting), and a suspension leg 57 that supports the mechanism 56 is fixed to the welding head base 4. At the time of welding, the scanning controller on the control panel 90 (FIG. 7) sets the welding head base 4 in advance with respect to the groove based on the groove x and z position deviation signal of the groove position sensor 55. The elevating motor 53 of the elevating mechanism and the horizontal drive motor of the horizontal x driving mechanism 52 are driven so that the predetermined heights z and x are obtained.

  A spray nozzle of the cut wire spraying device 58 is located behind the scanning roller 54 in the welding movement direction y of the welding head base 4. The cut wire spraying device 58 is supported by a manual adjustment mechanism 56. A cut wire stored in a cut wire hopper 59 attached to the welding head base 4 is supplied to the cut wire spraying device 58.

  In the usage mode in which the gas shield arc welding is performed, the gas shield arc welding torch 60 is disposed behind the cut wire spray nozzle in the welding movement direction y of the welding head base 4 and attached to the holder 61, and the torch 60 side Is connected to the connector of the main body side cable supported by the welding head base 4. The holder 61 is detachable from the gas shield arc welding torch 60. In a usage mode in which submerged arc welding is performed, the gas shield arc welding torch 60 is detached from the holder 61, and a cable connector (not shown) on the torch 60 side is removed from the connector of the main body side cable supported by the welding head base 4. The welding torch 60 is separated from the welding head base 4. The cable on the torch 60 side and the main body side cable have a shield gas supply hose and a welding wire guide pipe, and the shield gas supply hose in the main body side cable is supplied with a shield gas from a gas cylinder (not shown) on the welding carriage 3. Is done. A gas shield welding wire discharged from the pail pack 69 (FIGS. 6 and 7) on the welding carriage 3 is fed to the welding wire guide pipe in the main body side cable. In the gas shield welding mode, the welding wire that passes through the welding wire guide pipe in the main body side cable, passes through the cable connector, passes through the welding wire guide pipe in the torch side cable, and is fed from the lower end of the torch 60 toward the groove. . The shield gas that has passed through the shield gas supply hose in the torch side cable blows out from the lower end of the torch 60 toward the groove through the shield gas supply hose in the main body side cable.

  The holder 61 is fixed to the lower end of the relay leg 62, and the upper end of the relay leg 62 is fixed to the tip of the swing arm 64 of the swing device 63 in the groove width direction. The swing device 63 is supported by a suspension leg 68, and the suspension leg 68 is fixed to the welding head base 4.

  A first flux distribution nozzle 70 is located at the rear of the gas shield arc welding torch 60 in the welding head moving direction y of the welding head base 4, and a first submerged arc welding torch 71 (L) is located behind it. Thus, the flux spray nozzle 70 is supported by the backbone of the submerged arc welding torch 71. The backbone of the submerged arc welding torch 71 is supported by the welding head base 4. A welding wire is delivered to the submerged arc welding torch 71 from one of three wire coils 72 (FIG. 6) on the welding carriage 3. Flux is supplied to the first flux spray nozzle 70 from a flux hopper 73 (FIGS. 6 and 7).

  There is a second submerged arc welding torch 74 (T1) at a position behind the first submerged arc welding torch 71 (L) in the welding movement direction y of the welding head base 4, and the backbone is the welding head. It is supported by the base 4. A welding wire is discharged from one of the three wire coils on the welding carriage 3 to the submerged arc welding torch 74. A second flux spray nozzle 75 is located behind the second submerged arc welding torch 74 (T1) in the welding movement direction y of the welding head base 4, and a third submerged arc welding torch is located behind the second flux merging nozzle 75. 76 (T2), and the second flux spraying nozzle 75 is supported by the backbone of the third submerged arc welding torch 76. The backbone of the submerged arc welding torch 76 is supported by the welding head base 4. A welding wire is discharged from one of the three wire coils on the welding carriage 3 to the submerged arc welding torch 76. The flux is supplied from the flux hopper 73 to the flux spraying nozzle 75.

  There is a flux collector (suction nozzle) 77 at a position considerably behind the third submerged arc welding torch 76 (T2) in the moving direction y of the welding head base 4 during welding, and its base is the welding head base. 4 is supported. The flux collector 77 sucks the flux remaining around the groove after welding and returns it to the flux hopper 73 (FIGS. 6 and 7).

  In FIG. 9, the support structure part of the gas shield welding torch 60 is enlarged and shown. The swing mechanism that reciprocates the swing arm 64 of the swing device 63 in the groove width direction x is driven by an electric motor 66 via a speed reducer 65. The electric motor 66 rotationally drives the input shaft of the speed reducer 65, the output shaft of the speed reducer 65 rotationally drives the eccentric cam of the swing mechanism 64, and the eccentric cam reciprocates the crank in the x direction. The crank has a swinging width adjusting mechanism that shifts the swinging center (swinging center) to change the swinging width, and the swinging width can be manually adjusted by turning a knob 67 coupled to the mechanism.

  FIG. 10 shows an enlarged cross section taken along line F10-F10 in FIG. FIG. 10A shows a state where the gas shield arc welding torch 60 is attached to the holder 61 as shown in FIGS. The holder 61 is a combination of a pair of pressing arms 81, 82 that can be freely opened and closed by a hinge 83. At the tip of the arms 81 and 82, there is a notch that is a concave shape that is transverse in the y and z planes (paper surface of FIG. 9), and a screw rod 84 is fitted therein. One end of the screw rod 84 is a pin extending in the x direction and is coupled to the tip of the arm 81 so as to be rotatable around the pin. A female screw knob 86 with a sleeve 87 is screwed onto the male screw on the other end side of the screw rod 84, and the end face of the sleeve of the knob 86 is fixed to the outer surface (x, y) of the arm 82. The arms 81 and 82 hold the torch 60 between them. By rotating the knob 86 in the direction of releasing (loosing) the screw connection with the screw rod 84 and turning the screw rod 84 clockwise as shown in FIG. The arm 82 can be opened and the gas shield arc welding torch 60 can be detached from the holder 61 as shown in FIG. The gas shield arc welding torch 60 can be separated from the welding head base 4 by removing the torch side connector from the main body side connector of the gas shield arc welding cable.

Next, the usage mode and test welding results of the welding equipment also used for abmer arc welding and gas shield arc welding shown in FIGS.
1. Submerged arc welding The gas shielded arc welding torch 60 of the above welding equipment is separated from the welding head base 4 and submerged arc welding is carried out by the above welding equipment, so that the effect of the gap gap and the difference in the thickness of the thin plate on the welding quality. Was examined. The test materials are shown in Tables 1 to 5.

  As shown in (b) to (c) of FIG. 11, the steel plate to be welded having the chemical composition shown in Table 1 has a width of 500 mm, a length of 1500 mm, and a groove angle of 40 °. Since it was a mistake, a backing material was pasted on the rear surface of the groove of the tacked portion and tack welded. As a result, the back bead penetrating the back surface of the steel plate was ground with a grinder, and the groove back surface was smoothed. FIG. 11A shows a tack welding location.

  The welding conditions were as shown in Table 6 and Table 7 below. Welding No. on Table 7 1 and 4 are examples in which the back side groove gap is zero. Welding No. 2 is an example in which the back side groove gap is 3 mm. Welding No. 3 is an example in which the back side groove gap is 5 mm. Welding No. No. 4 is combined with a plate thickness of 9 mm as shown in (c) of FIG.

FIG. 12 shows the groove section cross-sectional shape (macro cross-section) and bead appearance (plane) obtained by submerged arc welding under the welding conditions shown in Table 7. The upper section of the macro section field in FIG. 12 is the section of the stationary section, and the lower section is the section of the tacking section. The upper row of the bead appearance column is the front bead, and the lower row is the back bead. As is apparent from FIG. 12, good welding results were obtained even when the back side groove gap was 0 to 5 mm and the difference was 3 mm. In the case of plate thicknesses of 10 mm and 35 mm separately performed, the back side groove gap was 0 to 5 mm, and good results were obtained as in the case of the plate thickness of 16 mm.
2. Gas shield arc welding The gas shield arc welding torch 60 of the above welding equipment is attached to the welding head base 4 and the thin plate is welded on one side by single-sided gas shield arc welding with a flux copper backing, resulting in a gap gap for the welding quality. The effects of misunderstandings were examined. Tables 8 to 10 show the welding materials. The back flux is the same as that shown in Table 4.

  A steel plate having a thickness of 6 mm shown in Table 10 (width 250 mm, length 750 mm) was 40 ° V-type groove year shown in FIG. 13, and the back groove width was 0 to 5 mm. Table 11 shows the welding conditions. Carbon dioxide gas (30 liter / min) was used as the shielding gas during welding. The results are also shown in Table 11.

14 and 15 show a groove section cross-sectional shape (macro cross section) and a bead appearance (plane) obtained by CO ₂ shielded arc welding under the welding conditions shown in Table 11.

In the case of gas shield single-sided welding with a plate thickness of 6 mm in a V-shaped groove having a groove angle of 40 °, a cut wire is dispersed in the groove, and the flux steels in Table 11 are combined with a 1.4 mmφ welding wire and a backing flux. As a result of the backing CO ₂ single-sided welding, good welding of a thin plate was obtained in a back side groove gap of 0 to 5 mm. However, if the misalignment is 3 mm, the surplus height on the upper plate side of the front bead becomes minute, the adhesion of the back flux is slow, and the back bead shape is slightly inferior.

  In addition, also in the welding result with a plate thickness of 9 mm separately performed, good results were obtained in the same manner.

  As described above, a multi-electrode submerged arc welding apparatus and a one-electrode gas shielded arc welding apparatus using a flux copper backing are suspended on one carriage 3, and on the carriage 3, wires necessary for submerged arc welding, a table A flux, a thin diameter (1.0 mmφ to 2.4 mmφ) wire pail pack necessary for gas shielded arc welding, and a common filler (cut wire or iron powder) spraying device for both weldings are mounted simultaneously. The backing support device and the back flux spraying carriage are also used for both weldings, and the thick plate is submerged arc welded, and the thin plate is gas shielded arc welded. In both weldings, the groove is a V groove, and a filler is sprayed into the groove. Torch and other arrangements of the head portion from the top side, groove detector (54: FIG. 8) -cut wire spraying device 58-gas shield arc welding torch 60-first front flux spraying nozzle 70 for submerged arc welding- First submerged arc welding torch 71 -second submerged arc welding torch 74 -second front flux spray nozzle 75 for submerged arc welding -third submerged arc welding torch 76 -fourth submerged arc if necessary The welding torch-surface flux collector 77 is preferable. Although it is possible to place the gas shielded arc welding torch 60 behind the submerged arc welding torch, the gas shielded arc welding wire has a small diameter and the bead is small. It is considered that the shield arc welding torch 60 is advantageously arranged close to the groove detector (54).

It is a block diagram which shows the one part outline | summary of the large plate welding equipment which is the arc welding apparatus of one Example of this invention. FIG. 2 is an enlarged side view of the backing support device 14 shown in FIG. 1. FIG. 3 is an enlarged side view of the backing copper plate support structure portion shown in FIG. 2, (a) shows a state immediately after spraying the back flux 5rf on the backing copper plate 21, and (b) shows the back flux 5rf on the large plate 5. The state of the submerged arc welding press-contacted to the back surface of is shown. It is an enlarged side view which expands and shows the surroundings of the raising / lowering frame 22 of the backing support apparatus 15 shown in FIG. It is a block diagram which shows the structure of the x drive device 100 which drives the electric motors 12M-15M of the x drive mechanism of the support devices 12-15 shown in FIG. It is an enlarged front view of the welding head base 4 suspended from the welding carriage 3 shown in FIG. It is an enlarged side view which shows the outline | summary of the support structure of the welding head base 4 suspended by the welding cart 3 shown in FIG. It is an enlarged front view which expands and shows further the welding head base 4 of FIG. It is an enlarged front view which expands and shows the gas shield arc welding torch 60 and the rocking device 63 shown in FIG. FIG. 10 is an enlarged sectional view taken along line F10-F10 in FIG. 9, where (a) shows the state shown in FIG. 9 in which the gas shield arc welding torch 60 is held by the holder 61, and (b) is removed from the holder 61; Therefore, a state in which the screw tightening of the knob 86 to the screw rod 84 is loosened is shown, and (c) shows a state in which the arm 82 is opened and the torch 60 is removed from the holder 61. (A) is a top view which shows the tack welding position before welding of the test material which carries out submerged arc welding using the large plate welding equipment shown in FIG. 1, (b)-(c) is a test material. It is a right view which shows a groove shape. It is a table | surface which shows the photographic image of the cross section of the front and back surface bead and a welding part (groove part) of the test material which carried out the submerged welding. It is a right view which shows the groove | channel of the test material which carries out a gas shield arc welding using the large plate welding equipment shown in FIG. Of CO ₂ shielded arc welding were tested material, the front and back surfaces beads and weld (groove portion) is a table showing a photograph of the cross section. Of CO ₂ shielded arc welding were tested material, the front and back surfaces beads and weld (groove portion) is a table showing a photograph of the cross section. It is a side view which shows the one aspect | mode of the positioning of the backing copper plate 21 with respect to the groove | channel of welding object.

Explanation of symbols

1: Rail 2: Portal type truck 3: Welding truck 4: Welding head base 5: Large plate 5rf: Back flux 5ff: Front flux 5cw: Cut wire Ew: Submerged arc welding wires 6-9: Rail 11: Back copper plate Dolly 12-16: Backing support device 15SN: Center sensor 15SL: Left limit sensor 15SR: Right limit sensor 21s: Copper plate support 21h: Air hose 22: Lifting frame 23: Backing copper plate carriage 24, 25: Arms 26, 27 : Two-stage cylinder type hydraulic jack 28: Chain conveyor 29: Groove plate 30, 31: Endless chain 32: Sprocket wheel 41: Wheel 42, 43: Vertical block 44, 45: Large plate conveying roller 46: Fixed roller 47: Lifting adjustment Roller 48: Belt conveyor 49: Flux distribution / collection vehicle 50: Vertical frame 4: Copying roller 55 of groove detector: groove position sensor 56: manual adjustment mechanism 57 in the x and z direction position: suspension leg 58: cut wire spraying device 59: cut wire hopper 60: gas shield arc welding torch 61: Holder 62: Relay leg 63: Oscillator 64: Oscillator arm 65: Reducer 66: Electric motor 67: Pick 68: Suspension leg 69: Pail pack 70: First flux spray nozzle 71: First submerged Arc welding torch (L)
72: Wire coil 73: Flux hopper 74: Second submerged arc welding torch (T1)
75: Second flux spray nozzle 76: Third submerged arc welding torch (T2)
77: Flux recovery device 81, 82: Arm 83: Hinge 84: Screw rod 85: Pin 86: Pick 87: Sleeve 90: Control panel 91b, 91t: Center arrangement indicating switch 92b: Left / right indicating switch (one end side indicating means)
92t: Left and right instruction switch (other end side instruction means)

Claims (11)

Backing material extending in the horizontal y direction;
Three or more backing support devices distributed in the horizontal y direction, each supporting the backing material, each having a backing material lifting mechanism and a backing material horizontal x drive mechanism; and
When driving the horizontal x drive mechanism of the support device at the other end without driving the horizontal x drive mechanism of the support device at one end in the y direction in the backing support device group, the support devices at both ends The backing material horizontal x drive mechanism of the support device between the two is a ratio of the distance from the support device at one end to the distance in the y direction between the support devices at both ends and the drive speed of the support device at the other end. A backing device comprising: an x drive device for backing material that is simultaneously driven at a product speed of;   Each backing horizontal x drive mechanism includes a respective pulse generator for generating an x drive sync pulse; the x drive device detects means for detecting the frequency of the x drive sync pulse generated by each pulse generator; and The frequency of the x drive synchronization pulse generated by the pulse generator of the support device at the other end is multiplied by the ratio to the frequency of the backing material horizontal x drive mechanism of the support device between the support devices at the both ends. 2. A means for driving the backing material horizontal x drive mechanism of the support device between the support devices at both ends so that the frequency of the x drive synchronization pulse generated by the pulse generator matches. Backing device.   The x drive device includes one end side instruction means for instructing x drive of the support device at the one end portion and another end side instruction means for instructing x drive of the support device at the other end portion. In response to the x driving instruction, the one end supporting device and the supporting device between the both end supporting devices are driven, and in accordance with the x driving instruction from the other end side instructing means, The backing device according to claim 1 or 2, wherein a support device between the support devices at both ends is driven.   The backing device according to claim 3, wherein the one end side instruction means and the other end side instruction means respectively instruct one of forward drive and backward drive in the x direction.   The x drive device includes center arrangement instruction means, and drives each support device of the backing support device group to the center in the x direction in response to the center arrangement instruction of the center arrangement instruction means. 4. The backing device according to any one of 4. The backing device according to any one of claims 1 to 5;
A welding carriage that travels in the horizontal y direction; a welding head base that is supported by a lifting mechanism and a horizontal x drive mechanism mounted on the welding carriage and is driven in the vertical z and horizontal x directions;
A groove detector supported by the welding head base; and
Scanning control means for controlling the welding head base to a predetermined height and horizontal x position with respect to the groove by driving the elevating mechanism and the horizontal x driving mechanism based on the groove detection of the groove detector;
An arc welding apparatus comprising:   The welding head base supports a filler spraying device, a gas shield arc welding torch holder, a surface flux spraying nozzle for submerged arc welding, and a plurality of submerged arc welding torches arranged side by side in the horizontal y direction; A means for supplying a gas shielded arc welding wire to a gas shielded arc welding torch held by the gas shielded arc welding torch holder, a means for supplying flux to the surface flux spray nozzle, and a submerged arc welding torch. 7. An arc welding apparatus according to claim 6, further comprising means for supplying a submerged arc welding wire to each.   From the head in the welding head direction with respect to the welding head base, the groove detector, the filler spraying device, the gas shield arc welding torch holder, the surface flux spraying nozzle for submerged arc welding, and a plurality of submerged The arc welding apparatus according to claim 7, wherein the arc welding torches are arranged in this order.   A first front flux diffusing nozzle is provided immediately before the foremost first submerged arc welding torch among the plurality of submerged arc welding torches, and a second submerged arc welding torch is provided after the first submerged arc welding torch. 9. The arc welding apparatus according to claim 8, wherein there is a second surface flux spray nozzle after the second submerged arc welding torch, and a third submerged arc welding torch after the second surface flux spray nozzle.   The arc welding apparatus according to claim 8 or 9, wherein the flux recovery means supported by the welding head base is located at a most downstream position with respect to a welding traveling direction y. 10. The apparatus according to claim 6, further comprising a rocking device supported by the welding head base that supports the gas shield arc welding torch holder and rocks and drives in a groove width direction x. The arc welding apparatus described.

Images