JP2006312186A - Arc length control method of double-side arc welding, and double-side arc welding equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a double-side arc welding method and double-side arc welding equipment using consumable electrode type welding and the non-consumable electrode type welding to consistently control the arc length of both sides of a base material, or the heat input of the non-consumable electrode type welding. <P>SOLUTION: In the double-side arc welding method, the arc length of a consumable electrode arc 1 is controlled to be a fixed value during the welding by setting the value of the sum (Vall) of the non-consumable electrode arc voltage (Vgta) measured by a non-consumable electrode arc voltage measurement circuit 11 and the arc voltage (Vgma-constant) on the consumable electrode side which is a preset fixed value to be the output voltage (Vout). The preset reference arc voltage (Vgta-const) on the non-consumable electrode side is corrected by the welding current value measured by a welding current measurement circuit 17. By comparing the corrected arc voltage value with the non-consumable electrode arc voltage (Vgta) measured by the non-consumable electrode arc voltage measurement circuit 11, the torch height of a non-consumable electrode welding torch 8 is adjusted so that the arc length of a non-consumable electrode arc 6 is controlled to be the fixed value. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a double-sided arc welding method in which consumable electrode welding and non-consumable electrode welding are combined, and in particular, an arc length control method suitable for stably and automatically controlling the arc length on both sides and a welding apparatus using the same. About.

  In the consumable electrode type gas shielded arc welding method, an arc is generated between an electrode (wire in the case of a consumable electrode type) connected to a DC or AC welding power source and a base material which is a material to be welded. And a method of welding by melting a base material. In this welding method, if the balance between the melting speed of the electrode wire and the feeding speed of the wire is broken for some reason, there are the following problems. That is, when the arc length is shortened, the wire is stabbed (stubbed), or conversely, when the arc length is lengthened, it is welded (burnback) to the power supply member, and the arc disappears and welding becomes impossible. For this reason, in the consumable electrode type gas shielded arc welding method, automatic control means for keeping the arc length constant is indispensable.

In general, when the distance between the electrode tip and the weld pool surface in consumable electrode arc welding is the apparent arc length La, the change in the apparent arc length La is expressed by the following equation.
dLa / dt = Vm−Vf (1)
Here, Vm: wire melting speed, Vf: wire feeding speed.

  The wire melting speed Vm mainly depends on the current after the wire material, the wire diameter, the type of shield gas, and the protruding length (distance between the power feeding portion and the wire tip) are determined. Therefore, the method of automatically increasing or decreasing the current according to the change in the arc length is effective for making the arc length constant.

As means for controlling the wire melting rate Vm with an actual welding apparatus, there are roughly the following two methods.
The first method is a method that utilizes the self-control action of a constant voltage characteristic welding power source often used in consumable electrode type gas shielded arc welding. FIG. 3 is a graph showing the arc length self-control characteristic of a constant voltage characteristic power source used in consumable electrode type welding.

  The arc characteristics with respect to the constant arc lengths La1 and La2 (La1 <La2) are characteristics in which the voltage gradually rises with respect to the current as shown in FIG. Assuming that the characteristic S of the welding power source that intersects this arc characteristic is set, when the arc length is increased from the length La1 to the length La2 for some reason, the arc voltage is slightly increased due to a slight increase in the arc voltage. The operating point moves from P1 to P2, and the current sharply decreases by ΔI. For this reason, when the wire melting speed Vm decreases and the wire feed speed is constant, the arc length is shortened to return to the length La1, and the operating point is also returned to P1.

  The second method is a method in which the current is feedback-controlled according to the arc length. In recent consumable electrode type gas shielded arc welding, a pulse current is often used, and in this case, a welding power source having a constant current characteristic is often used. In other words, in order to stabilize the droplet transfer due to the periodically pulsating pulse current, the current value is constant at a preset value. For this reason, the self-control action of the arc length by the constant voltage characteristic cannot be expected.

  FIG. 4 is an explanatory diagram showing an arc length control method in pulse arc welding in consumable electrode welding in which the wire 2 is supplied between the consumable electrode torch 5 and the base material 18 to generate the consumable electrode arc 1. In the case of a welding power source with constant current characteristics, a method is used in which the arc voltage that is approximately proportional to the change in the apparent arc length is detected, and this value is compared with the set reference voltage to increase or decrease the pulse frequency or pulse width. ing.

  FIG. 4A shows a pulse frequency modulation method in which the pulse width Tp is constant and the period T (T1, T2,...) Is changed to increase or decrease the average current. FIG. 4B shows a pulse width modulation method in which the period T is constant and the pulse width Tp is changed to increase or decrease the average current.

  That is, the arc length control method of FIG. 4 increases the current value because the arc length is short when the detected arc voltage is lower than the reference voltage, and conversely when the detected arc voltage is higher than the reference voltage, the arc length is shortened. Since the length is long, the current value is decreased to control the arc length to be constant.

  When using a welding power source with constant voltage characteristics, the output voltage from the welding power source is constant, and the resistance value fluctuation on the ground side causes voltage fluctuation, so the arc voltage fluctuates and the arc length fluctuates. . In addition, when using a welding power source with constant current characteristics, the arc voltage is measured to control the arc length. However, since the resistance fluctuation on the ground side causes voltage fluctuation, the measured arc voltage is actually measured. Arc voltage + fluctuating voltage, and the arc length is controlled by the measured value, so that the arc length fluctuates. Variations in arc length cause bead width variations, welding defects such as undercut, and troubles that increase spatter.

  In consumable electrode type gas shielded arc welding, an installation method of an earth cable to a workpiece is important. In automatic welding machines, it has been devised to perform this grounding automatically. For example, as in the invention of Japanese Patent No. 2500841, a method is adopted in which a grounding plate is pressed against a workpiece. However, some workpieces have a rough surface or are painted, and the resistance value of the contact part varies and the welding condition varies from workpiece to workpiece. was there. Further, when the workpiece is long, for example, as in the invention described in Japanese Patent Application Laid-Open No. 10-166152, a method is adopted in which the ground plate and the workpiece are brought into contact and slid. However, even in this case, some workpieces have a rough surface or are painted, and the resistance value of the contact part may fluctuate or the ground plate may be worn out. This may cause a problem that the resistance value of the contact portion fluctuates.

  Furthermore, if the installation position of the earth cable on the workpiece is inappropriate in consumable electrode gas shielded arc welding, the magnetic field formed by the welding current and the magnetic field formed by the earth current flowing through the workpiece and welding current It is known that the welding arc is deflected in the load direction of Lorentz force (electromagnetic force) during welding by this electromagnetic action (this phenomenon is generally referred to as magnetic blowing). When this magnetic blowing phenomenon is severe, welding defects such as frequent spattering, poor penetration, bead meandering and bead shape may occur, and countermeasures such as those disclosed in Japanese Patent Application Laid-Open No. 2001-300728 are proposed. May be required.

A double-sided arc welding method (US Pat. No. 5,990,446) has been developed by Yuming Zhang as one of the welding methods that are not affected by the resistance value fluctuation on the ground side.
In this welding method, welding torches are respectively installed on both sides of an object to be welded, and welding is performed by generating two arcs with one welding power source. The advantage of this welding method is that welding is performed from both sides at the same time, so the penetration into the base metal becomes deeper, and if the work is performed under appropriate conditions, the base metal can be welded through one side of the base material generated by welding. It is possible to reduce the angular deformation of the wire and to eliminate the installation of the ground wire.

  In particular, when the ground wire is not installed, the above-described troubles related to ground installation are eliminated. As a welding method described in US Pat. No. 5,990,446, a combination of plasma welding of a non-depressing electrode and TIG welding and a welding method of a combination of a consumable electrode and a non-consumable electrode have been proposed.

  The non-consumable electrode type gas shielded arc welding method is a method in which an arc is generated between a tungsten electrode connected to a welding power source having direct current or alternating current constant current characteristics and a base material, and the base material is welded by the generated heat. When adding a wire, it is the method of welding by melting a wire. In this non-consumable electrode welding, the wear of the tungsten electrode is small, the distance between the tip of the tungsten electrode and the base metal becomes the apparent arc length, and the variation in the distance between the tip of the tungsten electrode and the base material becomes the fluctuation of the arc length.

The arc characteristics with respect to the constant arc lengths La1 and La2 (La1 <La2) are characteristics in which the voltage gradually rises with respect to the current as shown in FIG. In the non-consumable electrode type welding, since a welding power source having a constant current characteristic is used, the P1 point of the arc length La1 moves to the P3 point when the arc length changes to La2, and the voltage increases. Therefore, by measuring the arc voltage and moving the tungsten electrode (welding torch) up and down with a slider or the like so that the measured voltage becomes the reference voltage compared with the preset reference voltage, the arc length can be controlled constantly. it can.
Patent No. 2500841 Japanese Patent Laid-Open No. 2001-300728 `` Welding of austenitic stainless steel using double sided are welding process '' Materials Science and Technology, October 2001 Vol.17 P1280-1284

Consists of a consumable electrode welding torch, a non-consumable electrode welding torch and a constant voltage DC power supply. A consumable electrode welding torch and a non-consumable electrode welding torch are installed with a base material sandwiched between them. In the double-sided arc welding method in which welding is performed by generating an arc from both sides of the base metal by connecting the positive electrode of the non-consumable electrode welding torch and the negative electrode of the constant voltage DC power supply, The output voltage value Vout is the sum of the arc voltage value Vgma for consumable electrode welding and the arc voltage value Vgta for non-consumable electrode welding, assuming that the voltage drop in the power supply cable and the voltage drop in the electrode power feeding portion can be ignored.
Vout = Vgma + Vgta (2)

  If the arc length of non-consumable electrode welding is constant, that is, the arc voltage value Vgta of non-consumable electrode welding is constant, the arc length of consumable electrode welding is kept constant by the self-control action of the constant voltage DC power supply. However, when the arc length of non-consumable electrode welding changes, there is a problem in that the arc length of consumable electrode welding is affected by the influence and the arc length is not constant.

  The arc length for non-consumable electrode welding is a constant arc length measured by measuring the arc voltage and moving the tungsten electrode (welding torch) up and down so that the measured voltage becomes the reference voltage compared to the preset reference voltage. Although a method of performing control has been invented, this method is established when the current value is constant using a welding power source with constant current characteristics, and when the current value fluctuates with a power source with constant voltage characteristics. Had the problem that this method could not be applied.

Furthermore, the heat input Q (J / cm) of welding is obtained by dividing the product of the current A (A) and the current V (V) by the welding speed S (cm / min), and is obtained by Expression (3).
Q = 60 × A × V / S (3)

  In general, in non-consumable electrode welding using a power supply having a constant current characteristic, if the current is constant and the welding speed is constant, the amount of heat input is also made constant by performing arc length control. However, the welding method has a problem that the amount of heat input is not constant because the current value fluctuates even when the arc length is controlled by voltage.

  Similarly, it consists of a consumable electrode welding torch, a non-consumable electrode welding torch, and a constant current type DC power source. A consumable electrode welding torch and a non-consumable electrode welding torch are installed with a base material interposed therebetween, and the wire of the consumable electrode welding torch A double-sided arc welding method in which a positive electrode of a current type DC power source is connected, a tungsten electrode of the non-consumable electrode welding torch is connected to a negative electrode of the constant current type DC power source, and an arc is generated from both sides of the base material to perform welding The arc length control of consumable electrode welding can be performed by increasing or decreasing the average current value according to the non-consumable electrode arc voltage value. However, in non-consumable electrode type welding, the current value fluctuates despite the use of a welding power source with constant current characteristics, so there is a problem similar to the double-sided arc welding method using a welding power source with constant voltage characteristics. It was.

  The object of the present invention is to propose a double-sided arc welding method and apparatus using consumable electrode welding and non-consumable electrode type welding that stably control the arc length on both sides of the base material or the heat input amount of non-consumable electrode type welding. There is to do.

The problems of the present invention are solved by the following means.
The invention according to claim 1 includes a consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant voltage DC power source 14 provided between the torches 5 and 8. The consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are installed with the base material 18 sandwiched therebetween, and the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant voltage type DC power source 14 are connected. In the double-sided arc welding method in which the tungsten electrode 7 and the negative pole of the constant voltage type DC power source 14 are connected and arcs 1 and 6 are respectively generated from both sides of the base material 18 to perform welding, the base material 18 and the constant voltage type DC power source are connected. Based on a non-consumable electrode arc voltage measurement circuit 11 that measures the voltage between the negative poles of the power supply 14, a current sensor 16 that measures the amount of power supplied to the torches 5, 8, and a detection value of the current sensor 16. A welding current measuring circuit 17 for measuring the contact current is provided, and a voltage value indicating circuit for indicating the voltage value of the constant voltage type DC power source 14 based on the measured value of the non-consumable electrode arc voltage in the non-consumable electrode arc voltage measuring circuit 11 15 is provided, and at the start of welding, a constant voltage type direct current is set to the sum (Vall-const) of the arc voltage value (Vgma-const) on the consumable electrode side and the arc voltage value (Vgta-const) on the non-consumable electrode side. The output voltage value (Vout) of the power supply 14 is output as a set value of the reference arc voltage. During welding, the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measurement circuit 11 and the predetermined constant value are set. The arc length of the consumable electrode 1 is controlled to be a constant value by making the output voltage value (Vout) the sum (Vall) of the arc voltage value (Vgma-const) on the consumable electrode side, and welding Welding power measured by the current measuring circuit 17 The reference arc voltage value (Vgta-const) set in advance on the non-consumable electrode side is corrected by the flow value, and the corrected arc voltage value and the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11 are corrected. Is a double-sided arc welding method in which the torch height of the non-consumable electrode welding torch 8 is adjusted to control the arc length of the non-consumable electrode arc 6 to be a constant value.

  The invention according to claim 2 includes a consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant voltage DC power source 14 provided between the torches 5, 8. The consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are installed with the base material 18 sandwiched therebetween, and the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant voltage type DC power source 14 are connected. In the double-sided arc welding method in which the tungsten electrode 7 and the negative pole of the constant voltage type DC power source 14 are connected and arcs 1 and 6 are respectively generated from both sides of the base material 18 to perform welding, the base material 18 and the constant voltage type DC power source are connected. Based on a non-consumable electrode arc voltage measurement circuit 11 that measures the voltage between the negative poles of the power supply 14, a current sensor 16 that measures the amount of power supplied to the torches 5, 8, and a detection value of the current sensor 16. A welding current measuring circuit 17 for measuring the contact current is provided, and a voltage value indicating circuit for indicating the voltage value of the constant voltage type DC power source 14 based on the measured value of the non-consumable electrode arc voltage in the non-consumable electrode arc voltage measuring circuit 11 15 is provided, and at the start of welding, a constant voltage DC is applied to the sum (Vall-const) of the arc voltage value (Vgma-const) on the consumable electrode side and the arc voltage value (Vgta-const) on the non-consumable electrode side. Output as a set value of the reference arc voltage of the output voltage value (Vout) of the power supply 14, and during welding, the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11 and the predetermined constant value By controlling the consumable electrode side arc voltage value (Vgma-const) as the output voltage value (Vout), the arc length of the consumable electrode arc 1 is controlled to be a constant value. Measured with consumable electrode arc voltage measurement circuit 11 By comparing the power value that is the product of the determined non-consumable electrode arc voltage value (Vgta) and the welding current value measured by the welding current measuring circuit 17 with the preset power value during welding on the non-consumable electrode side, A double-sided arc welding method in which the arc length of the non-consumable electrode arc 6 is controlled by adjusting the torch height of the non-consumable electrode welding torch 8 so that the power value at the time of welding on the non-consumable electrode side becomes the set power value. is there.

  The invention according to claim 3 includes a consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant current type DC power source 20 provided between the torches 5, 8. The consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are installed with the base material 18 sandwiched therebetween, and the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant current type DC power source 20 are connected. In the double-sided arc welding method in which the tungsten electrode 7 and the negative electrode of the constant current type DC power source 20 are connected and the arcs 1 and 6 are generated from both sides of the base material 18 respectively, welding is performed. A non-consumable electrode arc voltage measuring circuit 11 for measuring the voltage between the negative poles of the power source 20 and a consumable electrode arc voltage measuring circuit 2 for measuring the voltage between the positive poles of the base material 18 and the constant current DC power source 20 A current sensor 16 for measuring the amount of power supplied to the torches 5 and 8, a welding current measuring circuit 17 for measuring the welding current based on the indicated current value of the current sensor 16, and a consumable electrode arc voltage measuring circuit 22. Is provided with a current value indicating circuit 21 for indicating the current value of the constant current type DC power supply 20 based on the consumable electrode arc voltage value (Vgma) measured by the consumable electrode arc voltage value (Vgma). ) Is compared with the reference voltage value (Vgma-const) of the consumable electrode arc 1 set in advance by the current value indicating circuit 21, and the output current value from the constant current type DC power supply 20 is adjusted. The reference arc voltage value (Vgta-const) on the non-consumable electrode side set in advance by the welding current value measured by the welding current measuring circuit 17 is corrected so that the arc length is constant. By comparing the voltage value with the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11, the arc length of the non-consumable electrode arc 6 is adjusted by adjusting the torch height of the non-consumable electrode welding torch 8. Is a double-sided arc welding method in which the value is controlled to be a constant value.

  The invention according to claim 4 includes a consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant current type DC power source 20 provided between the torches 5 and 8. The consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are installed with the base material 18 sandwiched therebetween, and the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant current type DC power source 20 are connected. In the double-sided arc welding method in which the tungsten electrode 7 and the negative electrode of the constant current type DC power source 20 are connected and the arcs 1 and 6 are generated from both sides of the base material 18 respectively, welding is performed. A non-consumable electrode arc voltage measuring circuit 11 for measuring the voltage between the negative poles of the power source 20 and a consumable electrode arc voltage measuring circuit 2 for measuring the voltage between the positive poles of the base material 18 and the constant current DC power source 20 A current sensor 16 for measuring the amount of power supplied to the torches 5 and 8, a welding current measuring circuit 17 for measuring a welding current based on a detection value of the current sensor 16, and a consumable electrode arc voltage measuring circuit 22. Is provided with a current value indicating circuit 21 for indicating the current value of the constant current type DC power source 20 based on the measured value of the consumable electrode arc voltage, and the consumable electrode arc voltage value (Vgma) measured by the consumable electrode arc voltage measuring circuit 22 is defined as a current. The arc length of the consumable electrode arc 1 is adjusted by adjusting the output current value from the constant current type DC power supply 20 in comparison with the reference voltage value (Vgma-const) of the consumable electrode arc 1 preset by the value indicating circuit 21. Is controlled to be a constant value, and a power value that is a product of the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measurement circuit 11 and the welding current value measured by the welding current measurement circuit 17; The torch height of the non-consumable electrode welding torch 8 is adjusted so that the power value at the time of welding on the non-consumable electrode side becomes the set power value by comparison with the power value of the non-consumable electrode set for the This is a double-sided arc welding method for controlling the arc length of the non-consumable electrode arc 6.

  The invention described in claim 5 includes a consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant voltage DC power source 14 provided between the torches 5, 8. The consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are installed with the base material 18 sandwiched therebetween, and the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant voltage type DC power source 14 are connected. In the double-sided arc welding apparatus for connecting the negative electrode of the tungsten electrode 7 and the negative electrode of the constant voltage DC power supply 14 and performing welding by generating arcs 1 and 6 from both sides of the base material 18, respectively, the constant voltage DC power supply 14 is The output voltage of the constant voltage DC power supply 14 at the start of welding is the sum of the arc voltage value (Vgma-const) on the consumable electrode side and the arc voltage value (Vgta-const) on the non-consumable electrode side (Vall-const). Output voltage (Vou t) is output as a set value. During welding, the sum of the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11 and the arc voltage value (Vgma-const) set on the consumable electrode side in advance. (Vall) is set to an output voltage value (Vout) so that the arc length of the consumable electrode arc 1 is controlled to a constant value, and further, between the base 18 and the negative pole of the constant voltage DC power supply 14 A non-consumable electrode arc voltage measuring circuit 11 for measuring the voltage of the current, a current sensor 16 for measuring the amount of power supplied to the torches 5, 8, and a welding current measuring circuit for measuring the welding current based on the detected value of the current sensor 16. 17, a voltage value indicating circuit 15 that indicates the voltage value of the constant voltage DC power supply 14 based on the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11, and a welding current measuring circuit 17. Welding measured with The arc voltage value (Vgta-const) set in advance on the non-consumable electrode side is corrected by the flow value, and the corrected arc voltage value and the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11 The non-consumable electrode arc length adjustment circuit 10 for adjusting the torch height of the non-consumable electrode welding torch 8 so as to control the arc length of the non-consumable electrode arc 6 to a constant value, and the non-consumable electrode arc length It is a double-sided arc welding apparatus provided with a slider 9 operated by an adjustment circuit 10.

  The invention described in claim 6 includes a consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant voltage DC power source 14 provided between the torches 5, 8. The consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are installed with the base material 18 sandwiched therebetween, and the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant voltage type DC power source 14 are connected. In the double-sided arc welding apparatus for connecting the negative electrode of the tungsten electrode 7 and the negative electrode of the constant voltage DC power supply 14 and performing welding by generating arcs 1 and 6 from both sides of the base material 18, respectively, the constant voltage DC power supply 14 is The output voltage of the constant voltage DC power supply 14 at the start of welding is the sum of the arc voltage value (Vgma-const) on the consumable electrode side and the arc voltage value (Vgta-const) on the non-consumable electrode side (Vall-const). Output voltage (Vou t) is output as a set value. During welding, the sum of the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11 and the arc voltage value (Vgma-const) set on the consumable electrode side in advance. (Vall) is set to an output voltage value (Vout) so that the arc length of the consumable electrode arc 1 becomes a constant value, and further, between the base material 18 and the negative pole of the constant voltage DC power supply 14. A non-consumable electrode arc voltage measuring circuit 11 for measuring a voltage, a current sensor 16 for measuring the amount of power supplied to the torches 5 and 8, and a welding current measuring circuit 17 for measuring a welding current based on a detection value of the current sensor 16. And a power value that is the product of the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measurement circuit 11 and the welding current value measured by the welding current measurement circuit 17 and a preset non-consumable electrode. By comparison with the power value The non-consumable electrode arc for controlling the arc length of the non-consumable electrode arc 6 by adjusting the torch height of the non-consumable electrode welding torch 8 so that the power value at the time of welding on the non-consumable electrode side becomes the set power value. This is a double-sided arc welding apparatus provided with a length adjusting circuit 10 and a slider 9 operated by a non-consumable electrode arc length adjusting circuit 10.

  The invention according to claim 7 includes a consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant current type DC power source 20 provided between the torches 5, 8. The consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are installed with the base material 18 sandwiched therebetween, and the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant current type DC power source 20 are connected. In a double-sided arc welding apparatus that connects the negative electrode of the tungsten electrode 7 and the negative electrode of the constant current type DC power source 20 and generates arcs 1 and 6 from both sides of the base material 18 respectively, welding is performed. Based on a non-consumable electrode arc voltage measurement circuit 11 that measures the voltage between the negative poles of the power supply 20, a current sensor 16 that measures the amount of power supplied to the torches 5, 8, and a detection value of the current sensor 16. A welding current measuring circuit 17 that measures the contact current, a consumable electrode arc voltage measuring circuit 22 that measures a voltage between the base 18 and the positive electrode of the constant current type DC power source 20, and a consumable electrode arc voltage measuring circuit 22 Based on the measured value (Vgma) of the consumable electrode arc voltage, a current value indicating circuit 21 for indicating the consumable electrode arc output current value from the constant current type DC power supply 20 in comparison with a preset reference voltage, and a welding current The preset arc voltage value (Vgta-const) on the non-consumable electrode side is corrected by the welding current value measured by the measurement circuit 17, and the obtained corrected arc voltage value and the non-consumable electrode arc voltage measurement circuit 11 are measured. The non-consumable electrode arc length is controlled by adjusting the torch height of the non-consumable electrode welding torch 8 by comparing with the non-consumable electrode arc voltage value (Vgta) so that the arc length of the non-consumable electrode arc 6 becomes a constant value. The integer circuit 10, a double-sided arc welding apparatus provided with a slider 9 which is actuated by a non-consumable electrode arc length adjusting circuit 10.

  The invention according to claim 8 includes a consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant current type DC power source 20 provided between the torches 5, 8. The consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are installed with the base material 18 sandwiched therebetween, and the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant current type DC power source 20 are connected. In a double-sided arc welding apparatus that connects the negative electrode of the tungsten electrode 7 and the negative electrode of the constant current type DC power source 20 and generates arcs 1 and 6 from both sides of the base material 18 respectively, welding is performed. Based on a non-consumable electrode arc voltage measurement circuit 11 that measures the voltage between the negative poles of the power supply 20, a current sensor 16 that measures the amount of power supplied to the torches 5, 8, and a detection value of the current sensor 16. Welding current measuring circuit 17 for measuring the contact current, consumable electrode arc voltage measuring circuit 22 for measuring the voltage between the base 18 and the positive electrode of the constant current type DC power source 20, and the consumable electrode arc voltage measuring circuit 22 A current value indicating circuit 21 for indicating a consumable electrode arc output current value from the constant current type DC power source 20 in comparison with a preset reference voltage based on the consumable electrode arc voltage value (Vgma), and a non-consumable electrode A power value that is a product of a non-consumable electrode arc voltage value (Vgta) measured by the arc voltage measuring circuit 11 and a welding current value measured by the welding current measuring circuit 17 and a preset power value of the non-consumable electrode. By comparison, the non-consumable that controls the arc length of the non-consumable electrode arc 6 by adjusting the torch height of the non-consumable electrode welding torch 8 so that the power value during welding on the non-consumable electrode side becomes the set power value. Electrode arc This is a double-sided arc welding apparatus provided with a length adjusting circuit 10 and a slider 9 operated by a non-consumable electrode arc length adjusting circuit 10.

(Function)
According to the double-sided arc welding method and apparatus comprising the consumable electrode welding torch 5, the non-consumable electrode welding torch 8 and the constant voltage DC power supply 14 according to claim 1 and claim 5, the output voltage of the constant voltage DC power supply 14 is At the start of welding, the sum of the arc voltage value (Vgma-const) on the consumable electrode side and the arc voltage value (Vgta-const) on the non-consumable electrode side is set to the output voltage value (Vout) at the output of the constant voltage DC power supply 14 The reference arc voltage is set as a set value (Vall-const). During welding, the non-consumable electrode arc voltage measurement circuit 11 measures the voltage between the negative electrode of the base material 18 and the constant voltage DC power supply 14. The voltage of the consumable electrode arc 1 is made constant by setting the sum (Vall) of the consumable electrode arc voltage value (Vgta) and the preset arc voltage value (Vgma-const) on the consumable electrode side as the output voltage value (Vout). Self power of welding power supply with constant voltage characteristics Arc length of the consumable electrode arc 1 by control action is constant. Further, the arc voltage value (Vgta-const) on the non-consumable electrode side set in advance is corrected according to the arc characteristics shown in FIG. 3 based on the welding current value measured by the welding current measuring circuit 17 during welding. By adjusting the torch height of the non-consumable electrode welding torch 8 by comparing the measured non-consumable electrode arc voltage value with the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measurement circuit 11 The length of the side arc 6 can be controlled to be a constant value.

  According to the double-sided arc welding method and apparatus comprising the consumable electrode welding torch 5, the non-consumable electrode welding torch 8, and the constant voltage DC power source 14 according to claim 2 and claim 6, a consumable electrode set in advance at the start of welding. The sum of the arc voltage value (Vgma-const) on the side and the arc voltage value (Vgta-const) on the non-consumable electrode side (Vall-const) is the reference arc voltage of the output voltage value (Vout) of the constant voltage DC power supply 14 It is output as a set value. During welding, the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11 and the arc voltage value (Vgma-const) on the consumable electrode side which is the preset constant value. The non-consumable electrode arc measured by the non-consumable electrode arc voltage measuring circuit 11 is controlled so that the arc length of the consumable electrode arc 1 becomes a constant value by making the value of the sum (Vall) the output voltage value (Vout). Voltage value (Vgta) and welding current measurement circuit By comparing the power value that is the product of the welding current values measured in step 7 and the preset power value during welding on the non-consumable electrode side, the power value during welding on the non-consumable electrode side becomes the set power value. Thus, the arc length of the non-consumable electrode arc 6 is controlled by adjusting the torch height of the non-consumable electrode welding torch 8. Thus, the voltage value is controlled even if the current value fluctuates, so that the power amount (heat input amount) of the non-consumable electrode can be made constant.

  Further, according to the double-sided arc welding method and apparatus comprising the consumable electrode welding torch 5, the non-consumable electrode welding torch 8 and the constant current type DC power source 20 according to claim 3 and claim 7, the consumable electrode arc voltage measuring circuit 22 The measured consumable electrode arc voltage value (Vgma) is compared with the reference voltage of consumable electrode arc 1 preset by the current value indicating circuit 21 to adjust the consumable electrode arc output current value from the constant current type DC power supply 20. Thus, the arc length of the consumable electrode arc 1 is controlled to be a constant value, and the arc voltage value (Vgta-const) on the non-consumable electrode side set in advance is shown by the welding current value measured by the welding current measuring circuit 17. 3 is corrected, and the non-consumable electrode arc voltage value measured by the non-consumable electrode arc voltage measurement circuit 11 is compared with the non-consumable electrode arc voltage value (Vgta). Arc length of the non-consumable electrode 7 can be controlled to a constant value by adjusting the electrode torch height of the welding torch 8.

  According to the double-sided arc welding method and apparatus comprising the consumable electrode welding torch 5, the non-consumable electrode welding torch 8, and the constant current pressure type DC power source 20 according to claim 4 and claim 8, the consumable electrode arc voltage measuring circuit 22 is used. By comparing the consumable electrode arc voltage value (Vgma) with the reference voltage of the consumable electrode arc 1 preset by the current value indicating circuit 21, the consumable electrode arc output current value from the constant current type DC power source 20 is adjusted. The arc length of the consumable electrode arc 1 is controlled to be a constant value, the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11 and the welding current measured by the welding current measuring circuit 17. By comparing the power value, which is the product of the values, with the preset power value for welding on the non-consumable electrode side, the power value for welding on the non-consumable electrode side is set to the set power value. Electrode welding Adjust the height of the torch Ji 8 controls the arc length of the non-consumable electrode arc 6. Thus, the voltage value is controlled even if the current value fluctuates, so that the power amount (heat input amount) of the non-consumable electrode can be made constant.

  A double-sided arc welding method and apparatus comprising the constant voltage type DC power source 14 according to claims 1, 2 and 5 and 6 and the constant current type DC power source 20 according to claims 3, 4 and 7, 8. Therefore, in double-sided arc welding using consumable electrode type welding and non-consumable electrode type welding, the arc length on both sides or the electric energy (heat input) of non-consumable electrode type welding can be controlled stably. Further, double-sided arc welding using consumable electrode welding and non-consumable electrode welding can be stably performed. As a result, it is possible to stably carry out double-sided welding without installing a ground wire, and it is possible to carry out welding with little deformation after welding by simultaneously welding from both sides.

  Hereinafter, examples of the present invention will be given and described in more detail with reference to the drawings.

FIG. 1 is a schematic view showing a first embodiment of an arc length control method in the double-sided arc welding method of the present invention.
The consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are opposed to each other with the base material 18 as a material to be welded interposed therebetween. A wire 2 that becomes a consumable electrode is fed to the consumable electrode welding torch 5 by a feed roller 4 attached to a feed motor 3. On the other hand, a non-consumable tungsten electrode 7 is attached to the non-consumable electrode welding torch 8. Further, the positive electrode of the constant voltage DC power supply circuit 14 and the wire 2 of the consumable electrode welding torch 5 are connected by a consumable electrode power supply cable 13, and the negative electrode of the power supply power circuit 14 and the tungsten electrode 7 of the non-consumable electrode welding torch 8 are connected. The non-consumable electrode power supply cable 12 is used for connection.

  A voltage value indicating circuit 15 is connected to the constant voltage type DC power source power circuit 14 to control the output voltage from the constant voltage type DC power source power circuit 14. A voltage is applied between the wire 2 and the tungsten electrode 7 by the constant voltage DC power supply power circuit 14, and the consumable electrode arc 1 from the tip of the wire 2 and the non-consumable electrode arc 6 from the tip of the tungsten electrode 7 are transformed into the base material 18. Each occurs towards. FIG. 1 shows a state where the base material 18 is moving leftward, and a weld bead 19 is formed.

  The consumable electrode arc 1 is blown from the consumable electrode welding torch 5, and the non-consumable electrode arc 6 is blown from the non-consumable electrode welding torch 8 to the base material 18 side, respectively, argon gas, carbon dioxide, or a mixture of argon gas and carbon dioxide. It is shielded from air by shielding gas such as gas.

  A non-consumable electrode arc voltage measuring circuit 11 is provided between the base material 18 and the non-consumable electrode feeding cable 12 to measure the arc voltage of the non-consumable electrode (tungsten electrode 7). Further, a current sensor 16 and a current measurement circuit 17 are provided in a circuit through which the welding current flows to measure the current. The non-consumable electrode welding torch 8 is attached to the slider 9 so that the arc length corresponding to the distance between the base material 18 and the tip of the tungsten electrode 7 can be changed by moving the non-consumable electrode welding torch 8 up and down. It has become.

  The slider 9 is operated by a control signal from the non-consumable electrode arc length adjusting circuit 10. Further, the voltage value indicating circuit 15 and the non-consumable electrode arc length adjusting circuit 10 can capture the non-consumable electrode arc voltage value measured by the non-consumable electrode arc voltage measuring circuit 11. The non-consumable electrode arc length adjustment circuit 10 can take in the current value measured by the current measurement circuit 17.

  The arc voltage value Vgma-const of the consumable electrode arc 1 and the arc voltage value Vgta-const of the non-consumable electrode arc 6 are input to the voltage value indicating circuit 15 in advance. The voltage value indicating circuit 15 adds the arc voltage value Vgma-const of the consumable electrode arc 1 and the arc voltage value Vgta-const of the non-consumable electrode arc 6 to the constant voltage DC power supply circuit 14 as the reference arc voltage value Vall-const. When instructed, the constant voltage DC power supply circuit 14 applies an output voltage between the wire 2 and the tungsten electrode 7 to form the consumable electrode arc 1 and the non-consumable electrode arc 6, and welding starts.

  When the positions of the consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are constant and welding proceeds, the distance between the base material 18 and the consumable electrode welding torch 5 and the distance between the base material 18 and the non-consumable electrode welding torch 8 vary. First, the arc length of the non-consumable electrode arc 6 corresponding to the distance between the tip of the tungsten electrode 7 and the base material 18 varies.

  As shown in the above equation (2), the output voltage value Vout from the constant voltage type DC power supply circuit 14 assumes that the voltage drop in the power supply cable and the voltage drop in the electrode power supply part can be ignored. It is the sum of the value Vgma and the arc voltage value Vgta of non-consumable electrode welding.

  Since the output voltage value Vout is the reference arc voltage value V all-const at the start of welding, when the arc voltage value Vgta for non-consumable electrode welding varies, the arc voltage value Vgma for consumable electrode welding also varies. That is, when the arc length of the non-consumable electrode arc 6 is shortened, the arc length of the consumable electrode arc 1 is long, and when the arc length of the non-consumable electrode arc 6 is long, the arc length of the consumable electrode arc 1 is short.

  Therefore, after starting welding, the arc voltage value Vgta of the non-consumable electrode arc 6 is measured by the non-consumable electrode arc voltage measurement circuit 11 and the non-consumable electrode arc voltage value Vgta is set in advance by the voltage value indicating circuit 15. The indicated value is output to the constant voltage DC power supply circuit 14 as the new reference arc voltage value Vall-const as the sum of the arc voltage values Vgma-const, and the new reference arc voltage value Vall is output from the constant voltage DC power supply circuit 14 To do.

 Even if the arc voltage value Vgta of the non-consumable electrode arc 6 fluctuates by this control, the voltage between the wire 2 and the base material 18 of the consumable electrode welding torch 5 becomes the reference consumable electrode arc voltage value Vgma-const. The arc length of the consumable electrode arc 1 becomes constant due to the self-control action of the constant voltage characteristic of the DC power supply power circuit 14.

  Further, as a conventional method, the arc length control of the non-consumable electrode arc 6 is performed by measuring the non-consumable electrode arc voltage value Vgta by the non-consumable electrode arc voltage measuring circuit 11 and setting the reference arc preset by the non-consumable electrode arc length adjusting circuit 10. The arc length is obtained by moving the non-consumable electrode torch 8 up and down with the slider 9 so that the measured arc voltage value Vgta becomes the reference arc voltage value Vgta-const in comparison with the voltage value Vgta-const and the measured arc voltage value Vgta. The constant control of has been performed. However, this control method can be applied when the current value does not fluctuate using a welding power source with constant current characteristics, but when the current value fluctuates as in the double-sided arc welding method of this welding method, the heat input is the same. Otherwise, the weld bead becomes uneven and becomes unstable.

  Therefore, when the arc length is constant, the welding current is measured by the current sensor 16 and the current measurement circuit 17, and the non-consumable electrode preset by the welding current value measured by the non-consumable electrode arc length adjustment circuit 10 is measured. The reference arc voltage value Vgta-const is corrected according to the arc characteristics shown in FIG. 3, and the corrected arc voltage value Vgta-const of the non-consumable electrode and the non-consumable electrode arc voltage value Vgta measured by the non-consumable electrode arc voltage measurement circuit 11. By comparing the torch height of the non-consumable electrode welding torch 8 with the slider 9 by the comparison, the arc length of the non-consumable electrode 7 can be controlled constant.

  Furthermore, the amount of heat input during welding is expressed by equation (3). If the welding speed is constant, the amount of heat input is proportional to the power value that is the product of current and voltage. When a constant control of the arc length is performed by non-consumable electrode welding, the arc voltage is substantially constant, so the amount of heat input is proportional to the current. In the double-sided arc welding of this welding method, since the current value fluctuates, the heat input amount on the non-consumable electrode welding side also fluctuates. However, when the workpiece to be symmetric is thin, it is better to keep the heat input constant in order to make the weld bead constant.

  Therefore, the non-consumable electrode arc voltage measurement circuit 11 measures the non-consumable electrode arc voltage value Vgta, the current sensor 16 and the welding current measurement circuit 17 measure the welding current value, and the non-consumable electrode arc length adjustment circuit 10 measures the arc voltage. A power value that is the product of the current value and the current value is obtained, and the torch height of the non-consumable electrode welding torch 8 is adjusted by the slider 9 so that the two power values become the same by comparing with a preset power value. Thus, the amount of heat input can be made constant.

  Specifically, if the power value that is the product of the arc voltage value and the current value is greater than the set power value, the arc voltage is reduced by moving the welding torch 8 so that the arc length is shortened. The power value that is the product of the current values approaches the set power value.

  As described above, the double-sided arc welding including the constant voltage type DC power source 14 can stably control the arc length on both sides or the heat input amount of the non-consumable electrode type welding. Double-sided arc welding using welding can be performed stably. As a result, it is possible to stably carry out double-sided welding without installing a ground wire, and it is possible to carry out welding with little deformation after welding by simultaneously welding from both sides.

Another embodiment of the present invention is shown in FIG. FIG. 2 is a schematic diagram showing a second embodiment of the arc length control method of double-sided arc welding according to the present invention.
The consumable electrode welding torch 5 and the non-consumable electrode welding torch 8 are opposed to each other with the base material 18 as a material to be welded interposed therebetween. A wire 2 that becomes a consumable electrode is fed to the consumable electrode welding torch 5 by a feed roller 4 attached to a feed motor 3. A non-consumable tungsten electrode 7 is attached to the non-consumable electrode welding torch 8.

  The positive electrode of the constant current type DC power supply power circuit 20 and the wire 2 of the consumable electrode welding torch 5 are connected by the consumable electrode power supply cable 13, and the negative electrode of the power supply power circuit 20 and the tungsten electrode 7 of the non-consumable electrode welding torch 8 are nonconsumable. Connection is made with the electrode feeding cable 12.

  A current value indicating circuit 21 is connected to the constant current type DC power source power circuit 20 to control the output current from the constant current type DC power source power circuit 20. A consumable electrode arc voltage measurement circuit 22 is provided between the base material 18 and the consumable electrode power supply cable 13 to measure the arc voltage value Vgma of the consumable electrode. The current value indicating circuit 21 can capture the consumable electrode arc voltage value Vgma measured by the consumable electrode arc voltage measuring circuit 22. A non-consumable electrode arc voltage measurement circuit 11 is provided between the base material 18 and the non-consumable electrode feeding cable 12 to measure the arc voltage value Vgta of the non-consumable electrode.

  Further, a current sensor 16 and a current measurement circuit 17 are provided in a circuit through which the welding current flows, and current is measured. The non-consumable electrode welding torch 8 is attached to the slider 9, and the arc length corresponding to the distance between the base material 18 and the tip of the tungsten electrode 7 can be changed by moving the non-consumable electrode welding torch 8 up and down. ing.

  The slider 9 is operated by a control signal from the non-consumable electrode arc length adjusting circuit 10. The non-consumable electrode arc length adjustment circuit 10 can capture the non-consumable electrode arc voltage value measured by the non-consumable electrode arc voltage measurement circuit 11 and the current value measured by the current measurement circuit 17.

  The arc length control of the consumable electrode welding is performed by comparing the consumable electrode arc voltage value Vgma measured by the consumable electrode arc voltage measuring circuit 22 with a reference non-consumable electrode arc voltage value V gma-const preset by the current value indicating circuit 21. Then, the output current value from the constant current type DC power supply power circuit 20 is adjusted so that the voltage difference between them becomes zero. Specifically, if the measured consumable electrode arc voltage value Vgma is lower than the reference value, the output current value is increased to increase the consumable electrode arc length. Conversely, if the measured consumable electrode arc voltage value Vgma is higher than the reference value, the output current is increased. Decrease the value to shorten the consumable electrode arc length.

  Further, the reference arc voltage value Vgta-const on the non-consumable electrode side is corrected by the welding current value measured by the welding current measuring circuit 17, and the non-consumable electrode arc voltage measuring circuit 11 measures the corrected reference arc voltage value Vgta-const. By comparing with the consumable electrode arc voltage value Vgta, the torch height of the non-consumable electrode welding torch 8 is adjusted so that the arc length of the arc 8 of the non-consumable electrode 7 becomes a constant value.

  Further, in order to make the power value (heat input) of the non-consumable electrode 7 constant, similarly to the first embodiment, the non-consumable electrode arc voltage value V gta measured by the non-consumable electrode arc voltage measurement circuit 11 and welding are used. The torch height of the non-consumable electrode welding torch 8 is such that both power values are the same by comparing the power value that is the product of the welding current values measured by the current measuring circuit 17 with a preset power value. Can be adjusted to control the arc length of the non-consumable electrode 7.

  Thus, the double-sided arc welding comprising the constant current type DC power supply 20 can stably control the arc length on both sides or the heat input amount of the non-consumable electrode type welding. Double-sided arc welding using welding can be performed stably. As a result, it is possible to stably carry out double-sided welding without installing a ground wire, and it is possible to carry out welding with little deformation after welding by simultaneously welding from both sides.

  According to the double-sided arc welding method and apparatus comprising the constant voltage type DC power source 14 and the constant current type DC power source 20 of the present invention, the arc length on both sides of the base material 18 or the heat input amount of non-consumable electrode type welding can be stabilized. Since it can be controlled, it is possible to stably perform double-sided arc welding using consumable electrode welding and non-consumable electrode welding, so that welding with little deformation after welding can be performed in a wide range of technical fields. There is a possibility of becoming.

It is a schematic diagram which shows 1st embodiment of the arc length control method of the double-sided arc welding of this invention. It is a schematic diagram which shows 2nd embodiment of the arc length control method of the double-sided arc welding of this invention. It is a graph which shows the arc length self-control characteristic of the constant voltage characteristic power supply used by consumable electrode type | mold welding. It is explanatory drawing which shows the arc length control method in the pulse arc welding of consumable electrode type | mold welding.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Consumable electrode arc 2 Wire 3 Feeding motor 4 Feeding roller 5 Consumable electrode welding torch 6 Non-consumable electrode arc 7 Tungsten electrode 8 Non-consumable electrode welding torch 9 Slider 10 Non-consumable electrode arc length adjustment circuit 11 Non-consumable electrode arc voltage measurement Circuit 12 Non-consumable electrode power supply cable 13 Consumable electrode power supply cable 14 Constant voltage type DC power supply power circuit 15 Voltage value indicating circuit 16 Current sensor 17 Current measuring circuit 18 Base material 19 Welding bead 20 Constant current type DC power supply power circuit 21 Current value indicating Circuit 22 Consumable electrode arc voltage measurement circuit

Claims (8)

A consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant voltage DC power source 14 provided between the torches 5, 8 are provided. The electrode welding torch 8 is installed with the base material 18 sandwiched, the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant voltage DC power source 14 are connected, and the tungsten electrode 7 of the non-consumable electrode welding torch 8 and the constant voltage type. In the double-sided arc welding method in which the negative pole of the DC power supply 14 is connected and arcs 1 and 6 are respectively generated from both sides of the base material 18 to perform welding,
A non-consumable electrode arc voltage measurement circuit 11 that measures the voltage between the negative electrode of the base material 18 and the constant voltage DC power supply 14, a current sensor 16 that measures the amount of power supplied to the torches 5, 8, and the current sensor 16 A welding current measuring circuit 17 for measuring the welding current based on the detected value of
Furthermore, a voltage value indicating circuit 15 for indicating the voltage value of the constant voltage DC power supply 14 based on the measured value of the non-consumable electrode arc voltage in the non-consumable electrode arc voltage measuring circuit 11 is provided,
At the start of welding, the constant voltage DC power supply 14 outputs the sum (Vall-const) of the arc voltage value (Vgma-const) on the consumable electrode side and the arc voltage value (Vgta-const) on the non-consumable electrode side. The set value of the reference arc voltage of the voltage value (Vout) is output, and during welding, the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measurement circuit 11 and the consumable electrode which is the preset constant value. By controlling the sum of the arc voltage value (Vgma-const) on the side (Vall) as the output voltage value (Vout), the arc length of the consumable electrode arc 1 is controlled to be a constant value,
The preset reference arc voltage value (Vgta-const) on the non-consumable electrode side is corrected by the welding current value measured by the welding current measuring circuit 17, and the corrected arc voltage value and the non-consumable electrode arc voltage measuring circuit 11 are measured. By comparing with the non-consumable electrode arc voltage value (Vgta), the torch height of the non-consumable electrode welding torch 8 is adjusted to control the arc length of the non-consumable electrode arc 6 to be a constant value. Double-sided arc welding method. A consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant voltage DC power source 14 provided between the torches 5, 8 are provided. The electrode welding torch 8 is installed with the base material 18 sandwiched, the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant voltage DC power source 14 are connected, and the tungsten electrode 7 of the non-consumable electrode welding torch 8 and the constant voltage type. In the double-sided arc welding method in which the negative pole of the DC power supply 14 is connected and arcs 1 and 6 are respectively generated from both sides of the base material 18 to perform welding,
A non-consumable electrode arc voltage measurement circuit 11 that measures the voltage between the negative electrode of the base material 18 and the constant voltage DC power supply 14, a current sensor 16 that measures the amount of power supplied to the torches 5, 8, and the current sensor 16 A welding current measuring circuit 17 for measuring the welding current based on the detected value of
Furthermore, a voltage value indicating circuit 15 for indicating the voltage value of the constant voltage DC power supply 14 based on the measured value of the non-consumable electrode arc voltage in the non-consumable electrode arc voltage measuring circuit 11 is provided,
At the start of welding, the constant voltage DC power supply 14 outputs the sum (Vall-const) of the arc voltage value (Vgma-const) on the consumable electrode side and the arc voltage value (Vgta-const) on the non-consumable electrode side. The set value of the reference arc voltage of the voltage value (Vout) is output, and during welding, the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measurement circuit 11 and the consumable electrode which is the preset constant value. By controlling the sum of the arc voltage value (Vgma-const) on the side (Vall) as the output voltage value (Vout), the arc length of the consumable electrode arc 1 is controlled to be a constant value,
A power value that is the product of the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11 and the welding current value measured by the welding current measuring circuit 17 and a preset welding on the non-consumable electrode side. In comparison with the power value at the time, the arc of the non-consumable electrode arc 6 is adjusted by adjusting the torch height of the non-consumable electrode welding torch 8 so that the power value at the time of welding on the non-consumable electrode side becomes the set power value. A double-sided arc welding method characterized by controlling the length. A consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant current type DC power source 20 provided between the torches 5, 8 are provided. The electrode welding torch 8 is installed with the base material 18 sandwiched, the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant current type DC power source 20 are connected, and the tungsten electrode 7 of the non-consumable electrode welding torch 8 and the constant current type. In the double-sided arc welding method in which the negative pole of the DC power supply 20 is connected and arcs 1 and 6 are generated from both sides of the base material 18 for welding, respectively.
A non-consumable electrode arc voltage measuring circuit 11 that measures the voltage between the negative electrode of the base material 18 and the constant current type DC power supply 20, and a consumable electrode that measures the voltage between the positive electrode of the base material 18 and the constant current type DC power source 20. An arc voltage measuring circuit 22; a current sensor 16 for measuring the amount of power supplied to the torches 5 and 8; and a welding current measuring circuit 17 for measuring a welding current based on an indicated current value of the current sensor 16;
Furthermore, a current value indicating circuit 21 for indicating the current value of the constant current type DC power supply 20 based on the consumable electrode arc voltage value (Vgma) measured by the consumable electrode arc voltage measuring circuit 22 is provided.
A constant current equation in which the consumable electrode arc voltage value (Vgma) measured by the consumable electrode arc voltage measuring circuit 22 is compared with the reference voltage value (Vgma-const) of the consumable electrode arc 1 preset by the current value indicating circuit 21. By adjusting the output current value from the DC power supply 20, the arc length of the consumable electrode arc 1 is controlled to be a constant value,
The preset reference arc voltage value (Vgta-const) on the non-consumable electrode side is corrected by the welding current value measured by the welding current measuring circuit 17, and the corrected arc voltage value and the non-consumable electrode arc voltage measuring circuit 11 are measured. By comparing with the non-consumable electrode arc voltage value (Vgta), the torch height of the non-consumable electrode welding torch 8 is adjusted to control the arc length of the non-consumable electrode arc 6 to be a constant value. Double-sided arc welding method. A consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant current type DC power source 20 provided between the torches 5, 8 are provided. The electrode welding torch 8 is installed with the base material 18 sandwiched, the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant current type DC power source 20 are connected, and the tungsten electrode 7 of the non-consumable electrode welding torch 8 and the constant current type. In the double-sided arc welding method in which the negative pole of the DC power supply 20 is connected and arcs 1 and 6 are generated from both sides of the base material 18 for welding, respectively.
A non-consumable electrode arc voltage measuring circuit 11 that measures the voltage between the negative electrode of the base material 18 and the constant current type DC power supply 20, and a consumable electrode that measures the voltage between the positive electrode of the base material 18 and the constant current type DC power source 20. An arc voltage measuring circuit 22; a current sensor 16 for measuring the amount of power supplied to the torches 5 and 8; and a welding current measuring circuit 17 for measuring a welding current based on a detection value of the current sensor 16;
Furthermore, a current value indicating circuit 21 for indicating the current value of the constant current type DC power supply 20 based on the measured value of the consumable electrode arc voltage in the consumable electrode arc voltage measuring circuit 22 is provided,
A constant current equation in which the consumable electrode arc voltage value (Vgma) measured by the consumable electrode arc voltage measuring circuit 22 is compared with the reference voltage value (Vgma-const) of the consumable electrode arc 1 preset by the current value indicating circuit 21. By adjusting the output current value from the DC power supply 20, the arc length of the consumable electrode arc 1 is controlled to be a constant value,
The power value that is the product of the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11 and the welding current value measured by the welding current measuring circuit 17 and the preset power value of the non-consumable electrode As a result, the arc length of the non-consumable electrode arc 6 is controlled by adjusting the torch height of the non-consumable electrode welding torch 8 so that the power value during welding on the non-consumable electrode side becomes the set power value. A double-sided arc welding method characterized by that. A consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant voltage DC power source 14 provided between the torches 5, 8 are provided. The electrode welding torch 8 is installed with the base material 18 sandwiched, the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant voltage DC power source 14 are connected, and the tungsten electrode 7 of the non-consumable electrode welding torch 8 and the constant voltage type. In a double-sided arc welding apparatus that connects the negative pole of the DC power source 14 and generates arcs 1 and 6 from both sides of the base material 18 to perform welding.
The constant voltage DC power supply 14 determines the output voltage value of the constant voltage DC power supply 14 at the start of welding based on the arc voltage value (Vgma-const) on the consumable electrode side and the arc voltage value (Vgta-const) on the non-consumable electrode side. ) (Vall-const) is output as the set value of the output voltage value (Vout), and during welding, the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measurement circuit 11 and the preset consumption It has a configuration that controls the arc length of the consumable electrode arc 1 to be a constant value by making the sum (Vall) of the arc voltage value (Vgma-const) on the electrode side the output voltage value (Vout),
Furthermore, a non-consumable electrode arc voltage measurement circuit 11 that measures the voltage between the negative electrode of the base material 18 and the constant voltage DC power supply 14,
A current sensor 16 for measuring the amount of power supplied to the torches 5, 8;
A welding current measuring circuit 17 for measuring a welding current based on a detection value of the current sensor 16;
A voltage value indicating circuit 15 for indicating the voltage value of the constant voltage DC power supply 14 based on the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11;
A preset arc voltage value (Vgta-const) on the non-consumable electrode side is corrected by the welding current value measured by the welding current measuring circuit 17, and the corrected arc voltage value and the non-consumable electrode arc voltage measuring circuit 11 measure the non-consumable electrode arc voltage value. Non-consumable electrode arc length adjustment that controls the arc length of the non-consumable electrode arc 6 to a constant value by adjusting the torch height of the non-consumable electrode welding torch 8 by comparison with the consumable electrode arc voltage value (Vgta) Circuit 10;
A slider 9 actuated by the non-consumable electrode arc length adjustment circuit 10;
A double-sided arc welding apparatus characterized by comprising: A consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant voltage DC power source 14 provided between the torches 5, 8 are provided. The electrode welding torch 8 is installed with the base material 18 sandwiched, the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant voltage DC power source 14 are connected, and the tungsten electrode 7 of the non-consumable electrode welding torch 8 and the constant voltage type. In a double-sided arc welding apparatus that connects the negative pole of the DC power source 14 and generates arcs 1 and 6 from both sides of the base material 18 to perform welding.
The constant voltage type DC power source 14 uses the arc voltage value (Vgma-const) on the consumable electrode side and the arc voltage value (Vgta-const) on the non-consumable electrode side, based on the output voltage of the constant voltage DC power source 14 at the start of welding. Is output as the set value of the output voltage value (Vout), and during welding, the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measurement circuit 11 and a preset consumable electrode are output. It has a configuration that controls the arc length of the consumable electrode arc 1 to be a constant value by making the sum (Vall) of the arc voltage value (Vgma-const) on the side the output voltage value (Vout),
Furthermore, a non-consumable electrode arc voltage measurement circuit 11 that measures the voltage between the negative electrode of the base material 18 and the constant voltage DC power supply 14,
A current sensor 16 for measuring the amount of power supplied to the torches 5, 8;
A welding current measuring circuit 17 for measuring a welding current based on a detection value of the current sensor 16;
The power value that is the product of the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measuring circuit 11 and the welding current value measured by the welding current measuring circuit 17 and the preset power value of the non-consumable electrode As a result, the arc length of the non-consumable electrode arc 6 is controlled by adjusting the torch height of the non-consumable electrode welding torch 8 so that the power value during welding on the non-consumable electrode side becomes the set power value. A non-consumable electrode arc length adjustment circuit 10;
A slider 9 actuated by a non-consumable electrode arc length adjustment circuit 10;
A double-sided arc welding apparatus characterized by comprising: A consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant current type DC power source 20 provided between the torches 5, 8 are provided. The electrode welding torch 8 is installed with the base material 18 sandwiched, the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant current type DC power source 20 are connected, and the tungsten electrode 7 of the non-consumable electrode welding torch 8 and the constant current type. In a double-sided arc welding apparatus that connects the negative pole of the DC power source 20 and generates arcs 1 and 6 from both sides of the base material 18 for welding, respectively.
A non-consumable electrode arc voltage measuring circuit 11 for measuring the voltage between the negative electrode of the base material 18 and the constant current type DC power supply 20,
A current sensor 16 for measuring the amount of power supplied to the torches 5, 8;
A welding current measuring circuit 17 for measuring a welding current based on a detection value of the current sensor 16;
A consumable electrode arc voltage measuring circuit 22 for measuring the voltage between the base material 18 and the positive electrode of the constant current type DC power source 20;
Based on the measured value (Vgma) of the consumable electrode arc voltage in the consumable electrode arc voltage measuring circuit 22, the consumable electrode arc output current value from the constant current type DC power supply 20 is indicated in comparison with a preset reference voltage. Current value indicating circuit 21 to perform,
The preset arc voltage value (Vgta-const) on the non-consumable electrode side is corrected by the welding current value measured by the welding current measuring circuit 17, and the obtained corrected arc voltage value and the non-consumable electrode arc voltage measuring circuit 11 are corrected. A non-consumable electrode that controls the arc length of the non-consumable electrode arc 6 to a constant value by adjusting the torch height of the non-consumable electrode welding torch 8 by comparison with the measured non-consumable electrode arc voltage value (Vgta) An arc length adjusting circuit 10;
A slider 9 actuated by a non-consumable electrode arc length adjustment circuit 10;
A double-sided arc welding apparatus characterized by comprising: A consumable electrode welding torch 5 having a wire 2, a non-consumable electrode welding torch 8 having a tungsten electrode 7, and a constant current type DC power source 20 provided between the torches 5, 8 are provided. The electrode welding torch 8 is installed with the base material 18 sandwiched, the wire 2 of the consumable electrode welding torch 5 and the positive electrode of the constant current type DC power source 20 are connected, and the tungsten electrode 7 of the non-consumable electrode welding torch 8 and the constant current type. In a double-sided arc welding apparatus that connects the negative pole of the DC power source 20 and generates arcs 1 and 6 from both sides of the base material 18 for welding, respectively.
A non-consumable electrode arc voltage measuring circuit 11 for measuring the voltage between the negative electrode of the base material 18 and the constant current type DC power supply 20,
A current sensor 16 for measuring the amount of power supplied to the torches 5, 8;
A welding current measuring circuit 17 for measuring a welding current based on a detection value of the current sensor 16;
A consumable electrode arc voltage measuring circuit 22 for measuring the voltage between the base material 18 and the positive electrode of the constant current type DC power source 20;
Based on the consumable electrode arc voltage value (Vgma) measured by the consumable electrode arc voltage measuring circuit 22, the consumable electrode arc output current value from the constant current type DC power supply 20 is indicated in comparison with a preset reference voltage. A current value indicating circuit 21;
The power value that is the product of the non-consumable electrode arc voltage value (Vgta) measured by the non-consumable electrode arc voltage measurement circuit 11 and the welding current value measured by the welding current measurement circuit 17 and the preset power of the non-consumable electrode The arc length of the non-consumable electrode arc 6 is controlled by adjusting the torch height of the non-consumable electrode welding torch 8 so that the power value at the time of welding on the non-consumable electrode side becomes the set power value by comparison with the value. A non-consumable electrode arc length adjustment circuit 10,
A slider 9 actuated by a non-consumable electrode arc length adjustment circuit 10;
A double-sided arc welding apparatus characterized by comprising:

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