Abstract: A method for controlling a bead, in one-side automatic welding wherein a backing metal strip is adhered to the back side of a pair of work pieces through an inorganic material and arc welding is applied to the work pieces on the surface side thereof, comprises:detecting an electrical signal between the work pieces and the backing metal strip to control a weld current so that the detected electrical signal can be equal to a predetermined reference signal; and detecting the controlled weld electrical current and putting the detected weld electrical current into a formula of V.sub.1 =V.sub.0 .multidot.I.sub.L /I.sub.L0 to calculate a welding speed; and controlling the welding speed in accordance with the calculated welding speed, where V.sub.1 represents the calculated welding speed, V.sub.0 an initial value of the welding speed, I.sub.L the detected weld electrical current and I.sub.L0 a predetermined reference weld current. The electrical signal can be an electrical current signal or a voltage signal.

Abstract: An automatic arc-welding method, which comprises, when welding two objects to be welded together by means of a welding wire along a first groove formed between the objects to be welded on a first side thereof, continuously determining by calculation a target welding current, with which a depth of penetration agrees with a target value thereof, on the basis of the root gap, the material of the welding wire and the like; continuously determining by calculation a target feeding rate of the welding wire, at which an extension length of the welding wire agrees with a target value thereof, on the basis of the welding current, the material of the welding wire and the like; continuously determining by calculation a target welding speed, at which a height of the weld bead agrees with a target value thereof, on the basis of the feeding rate of the welding wire, the material of the welding wire, the root gap and the like; and on the other hand, when welding the objects to be welded together by means of the welding wire

Abstract: An automatic arc-welding method, which comprises when welding two objects to be welded together by means of a welding wire along a groove formed between the objects to be welded, continuously detemrining by calculation a target welding current, with which a depth of penetration agrees with a target value thereof, on the basis of the root gap, the material of the welding wire and the like; continuously determining by calculation a target feeding rate of the welding wire, at which an extension length of the welding wire agrees with a target value thereof, on the basis of the welding current, the material of the welding wire and the like; continuously determining by calculation a target welding voltage, with which a length of the arc agrees with a target value thereof, on the basis of the welding current, the feeding rate of the welding wire, the material of the welding wire and the like; and automatically controlling the welding current, the feeding rate of the welding wire and the welding voltage on the basis

Abstract: An automatic arc-welding method, which comprises, when welding two objects to be welded together by means of a welding wire along a groove formed between the objects to be welded, continuously determining by calculation a target welding current, with which a depth of penetration agrees with a target value thereof, on the basis of the root gap, the material of the welding wire and the like; continuously determining by calculation a target feeding rate of the welding wire, at which an extension length of the welding wire agrees with a target value thereof, on the basis of the welding current, the material of the welding wire and the like; and continuously determining by calculation a target welding speed, at which a height of the weld bead agrees with a target value thereof, on the basis of the feeding rate of the welding wire, the material of the welding wire, the root gap and the like; thereby automatically controlling the welding current, the feeding rate of the welding wire and the welding speed on the basi

Abstract: An automatic fillet welding method for effecting the welding by rotating a welding electrode and thereby rotating an arc at a high speed. By rotating the arc with a predetermined rotation direction, rotation speed and rotation diameter, a weld metal is prevented from running downward thereby forming a bead having uniform leg lengths and an excellent depth of penetration.

Abstract: A groove tracing control method for a fillet welding effected by rotating a welding torch and thereby rotating an arc at a high speed. The groove tracing control of the welding torch is effected in accordance with variations in the voltage waveform of the rotating arc and in this way the groove tracing is effected in real time in a noncontact manner with a high degree of accuracy.

Abstract: A method and an apparatus for automatically setting the weaving reversing position in automatic arc welding wherein the welding electrode is subjected to weaving within the extent of the welding groove or bevel.The position of reversing the electrode weaving direction is set by using a mean value of the height levels of the welding electrode subjected to weaving along the groove bottom transversely of the proceeding direction of welding. In this manner, the weaving reversing position is stabilized to promote the formation of the optimum welding bead.

Abstract: A control method in which during arc welding a welding torch is moved in its axial direction so as to maintain the arc current or welding current at a predetermined value and thereby maintain the arc length constant and the torch is caused to weave in the width direction with respect to the direction of welding while changing the direction of the weaving each time the axial displacement or position of the torch attains a predetermined value. The weaving speed is decreased when the torch approaches each turning point of the weaving and the gain of the speed control for the torch axial movement is increased when the torch approaches each turning point in the course of its movement from the central area toward the turning point during each weaving cycle.

Abstract: A welding control method in which a deviation of a groove line or variation of a groove width is detected by utilizing the characteristics of a welding arc itself without using a separate sensor and a welding torch is caused to accurately follow the groove line. The oscillation width of the welding torch is detected and the proper welding speed for providing a weld bead of a predetermined height is calculated in accordance with the detected oscillation width thereby automatically controlling the welding speed in accordance with the calculated welding speed value for every cycle of the oscillation or every integral multiple thereof.

Abstract: In the multi-layer welding of a joint of two pieces of metal to be welded by arc welding, the proper number of passes and the desired tracing positions of a welding torch for each layer are automatically established during the welding of the preceding layer. The welding torch is subjected to a Y-axis control so as to maintain constant the arc voltage or current during the welding and simultaneously the torch is caused to weave in the direction of an X-axis within the groove. The tracing of the groove by the torch is accomplished by controlling the weaving turning positions of the torch in accordance with the X-axis and Y-axis direction displacement data of the torch and the torch displacements in the X-axis direction are compared with a predetermined value thereby determining the proper number of passes to be made in the welding of the next layer.

Abstract: A rotary arc-welding apparatus which comprises: a rotatable nozzle having in its interior thereof a passage for directing a consumable welding electrode eccentrically from the center axis of the nozzle toward a groove formed between objects of welding; a consumable welding electrode feeding mechanism for continuously directing the consumable welding electrode toward the groove through the nozzle; a welding current feeding mechanism for feeding a welding current to the nozzle, which comprises a current receiving plate fixed to the top end of the nozzle, a brush having on the upper surface thereof a current feeding plate, the brush and the current receiving plate having a flat contact interface therebetween, a plurality of rods for stationarily holding the brush and the current feeding plate, and a plurality of springs for applying a pressure onto the contact interface between the brush and the current receiving plate; a nozzle rotating mechanism for rotating the nozzle about the center axis thereof at a high s

Abstract: An arc-welding method, which comprises: arc-welding objects of welding together along the line of a groove formed between said objects of welding by continuously moving a welding electrode along the line of said groove while reciprocating said welding electrode in the width direction of said groove; characterized by: calculating at prescribed time intervals, for each one reciprocation of said welding electrode in the width direction of said groove, deviations (I-Io) of values (I) of one of arc current and arc voltage from a previously set reference value (Io), for each of left-side deviations (L) and right-side deviations (R) relative to the vertical plane which passes through the center of amplitude of said one reciprocation of said welding electrode and is parallel to the line of said groove; calculating at said time intervals, when said welding electrode moves over the left side of said groove relative to said vertical plane, differences (L-R) between said left-side deviations (L) and the immediately prece

Abstract: A welding method comprises rotating a nozzle (3) provided with a welding electrode (9) eccentrically from the center axial line (a) thereof within a groove (2). The center axial line (a) of the nozzle is aligned with the center of the groove (2) by smoothing values of variation in welding current or welding voltage for each of the left and right half cycles of the nozzle and controllably moving the nozzle horizontally at right angles to the welding direction so that the difference between these values becomes null. The height of the nozzle (3) relative to the groove (2) is maintained at a prescribed distance by smoothing values of variation in welding current or welding voltage and controllably moving vertically the nozzle (3) so that the difference between the thus smoothed value and a set value becomes null.

Abstract: In an automatic arc-welding method, which comprises: continuously moving a carriage along the longitudinal direction of a groove formed between the objects of welding; reciprocally moving in the width direction of the groove a welding electrode directed substantially vertically to said groove through a welding torch fitted to said carriage, following the groove face of said groove; producing an arc between the top of said electrode and said groove; moving said torch vertically up and down so that the value (E.sub.v) of the arc voltage or arc current agrees with a previously set value (E.sub.o); on the other hand, continuously detecting a vertical position of said torch as a value of voltage (e.sub.Y) indicated by a potentiometer; reversing the direction of movement of said torch in the width direction of said groove at the moment when said value of voltage (e.sub.

Abstract: In a rotary arc-welding method which comprises: directing a nozzle substantially vertically toward a weld zone of objects of welding; feeding a consumable welding electrode through said nozzle eccentrically from the center axis of said nozzle toward said weld zone; feeding welding current to said consumable welding electrode to produce an arc between the tip of said consumable welding electrode and said weld zone to weld said objects of welding with each other by means of the arc heat; rotating said nozzle to cause a circular movement of said arc from the tip of said consumable welding electrode corresponding to the eccentricity thereof; and, feeding a shielding gas toward said weld zone to shield said arc and said weld zone from the open air; the improvement characterized in that: the diameter of said consumable welding electrode is limited within the range of from 0.8 to 1.

Abstract: An arc-welding method comprises reciprocally moving a welding electrode substantially vertically toward a groove formed between objects of welding, in the width direction of the groove, following the face of the groove; producing, by a welding torch, an arc between the tip of the electrode and the groove; moving the torch vertically up and down so that one of an arc voltage and arc current of the arc agrees with a previously set value; continuously detecting the vertical position of the torch as a value of voltage indicated by a potentiometer; and reversing the direction of the movement of the torch in the width direction of the groove at the moment when the detected value of voltage agrees with a previously set value of voltage.

Abstract: An arc welding method in which with a welding electrode being oscillated within the groove in the width direction thereof, the movement of the electrode in the upright or vertical direction is controlled to always maintain the arc length constant. The groove of a predetermined shape is subjected to arc welding with predetermined welding speed and wire feed speed so that when a half cycle of the electrode oscillation is completed, the height direction displacement of the electrode is integrated over the time to obtain a cross-sectional area S.sub.o described by the electrode and also an oscillation stroke X.sub.o made by the electrode is obtained, thus storing the cross-sectional area S.sub.o and the oscillation stroke X.sub.o. When the next half cycle is completed, a cross-sectional area S and an oscillation stroke X are similarly obtained so that the welding speed or the wire feed speed is controlled to vary and thereby to vary the cross-sectional area of metal deposition by an amount .DELTA.