JPH06344143A - Automatic tig multi-layer welding method and its equipment - Google Patents

Abstract

PURPOSE:To easily set up a guide rail where a welding torch is arranged along a weld line, to carry out automatic profile of the welding torch on second and succeeding layers and to simplify welding. CONSTITUTION:The groove face position passing both corner parts of the groove bottom face of a weld zone 11a by the specified width is detected in order from the change of the arc voltage at the time of root running, a center line of the weld zone 11a is calculated from the detected groove face position, then, the welding torch 15 is woven based on this center line and the second and succeeding layers are welding.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic TIG multi-layer welding method and apparatus, and more specifically, it can automatically copy a welding torch of the second and subsequent layers and arranges the welding torch along a welding line. TECHNICAL FIELD The present invention relates to an automatic TIG multi-layer welding method and apparatus that can perform automatic welding even if a guide rail is roughly arranged and simplify welding.

[0002]

2. Description of the Related Art TI has been conventionally used for welding stainless steel plates.
Multi-layer automatic welding using G (tungsten-inert-gas) welding has been performed, but the conventional TIG welding method is, for example, a trolley that moves on a guide rail arranged along the welding line of the material to be welded. A welding torch was attached to the welding torch, and the welding portion was automatically weaved as needed, and the welding portion was reciprocated a plurality of times to perform multi-layer welding.

[0003]

However, mounting the guide rail parallel to the welding line is an extremely laborious task, and if the guide rail is out of alignment, proper welding cannot be performed along the welding line. There was a point. Therefore, there is an inconvenience that the worker must constantly observe the welding state even during welding after setting the guide rail. The present invention has been made in view of such circumstances, and a guide rail for arranging the welding torch along the welding line can be easily installed, and further, the welding torch of the second and subsequent layers can be automatically copied to simplify welding. Automatic TIG
An object of the present invention is to provide a multi-layer welding method and apparatus.

[0004]

A method according to the above-mentioned object.
The described automatic TIG multi-layer welding method includes a welding torch attached to a trolley having a first drive means that moves in a length direction of a guide rail arranged along a welded portion of a material to be welded. , The first driving means and the second driving means for moving the welding torch in the width direction of the guide rail are weaved to perform welding of the first layer, and arc during welding of the first layer. From the change in the voltage, the groove surface position that has passed both corners of the groove bottom surface of the welded portion by a predetermined width is detected, the center line of the welded portion is calculated from the detected groove surface position, and the calculated The second and subsequent layers are welded while weaving the welding torch based on the center line.

An automatic TIG multi-layer welding apparatus according to a second aspect of the present invention has a first driving means and is provided on a guide rail arranged along the welded portion of the material to be welded in the longitudinal direction of the rail. A moving dolly, a welding torch attached to the dolly, second driving means for moving the welding torch in the width direction of the guide rail, and third moving means for moving the welding torch in the thickness direction of the guide rail An automatic TIG multi-layer welding apparatus comprising: a driving means of No. 1 and a control device of the first to third driving means, wherein the control device detects an arc voltage during welding and performs the third driving. Means for moving the welding torch in the thickness direction of the guide rail to control the arc length within a certain range, and the first and second driving means for driving the welding torch. Melted Groove face detection for weaving the welded part of the material and detecting the position of the groove face which has passed through both corners of the groove bottom face of the welded part by a predetermined width from the change of the arc voltage at the time of welding the first layer Means, and a centerline calculating means for calculating a centerline of the welded portion from the detected groove surface position,
Centerline reference welding means for weaving the welding torch by a pre-entered numerical value based on the calculated centerline and performing welding of the second and subsequent layers is provided.

[0006]

In the automatic TIG multi-layer welding method according to claim 1, the carriage is moved along the guide rail by the first driving means, and the welding torch is moved in the width direction of the guide rail by the second driving means. Thus, the first layer is welded while weaving the welding torch. Next, from the change of the arc voltage at the time of welding the first layer, the positions of the groove surfaces that have passed through the both corners of the groove bottom surface of the welded portion by a predetermined width are sequentially detected, and the position of the welded portion is detected from the detected groove surface position. Calculate the centerline. After that, since the welding torch is weaved on the basis of the calculated center line and the welding of the second and subsequent layers is performed, it is possible to automatically copy the welding torch of the second and subsequent layers, and the welding torch is welded. Even if the guide rails installed along the rails are roughly installed, automatic welding can be performed and welding can be simplified.

Further, in the automatic TIG multi-layer welding apparatus according to the second aspect, the carriage is moved along the guide rail by the first driving means, and the welding torch is moved in the width direction of the guide rail by the second driving means. The first layer is welded while weaving the welding torch by moving the welding torch. At this time, the arc voltage during welding is detected, and the arc length control means of the control device drives the third drive means based on the detection result to move the welding torch in the thickness direction of the guide rail. Control the length within a certain range. Then, from the change in the arc voltage at the time of welding the first layer, the groove surface position which has passed through both corners of the groove bottom surface of the welded portion by a predetermined width is detected by the groove surface detecting means of the control device, and detected. The center line calculation means of the control device calculates the center line of the welded portion from the groove surface position. afterwards,
Welding of the second and subsequent layers is performed while weaving the welding torch according to the numerical values input in advance by the centerline reference welding means of the control device, using the calculated centerline as a reference. Automatic welding of the torch is enabled, and even if the guide rails for arranging the welding torch along the welding line are roughly installed, automatic welding can be performed and welding can be simplified.

[0008]

Embodiments of the present invention will now be described with reference to the accompanying drawings to provide an understanding of the present invention. In the embodiment, the length direction of the guide rail is the Z direction, the width direction of the guide rail is the X direction, and the thickness direction of the guide rail is the Y direction. 1 is a perspective view showing a state of use of an automatic TIG multi-layer welding apparatus according to an embodiment of the present invention, FIG. 2 is a front view thereof, FIG. 3 is a bottom view thereof, and FIG. 4 is a side view thereof. 5 is a block diagram of a control device of the automatic TIG multi-layer welding apparatus of the embodiment, FIG. 6 is an overall flow chart of the control device of FIG. 5, FIG. 7 is a main part flow chart of the control device of FIG. 5, and FIG. 6 is a graph showing control over time by the control unit of FIG.

As shown in FIG. 1, an automatic TIG multi-layer welding apparatus 10 according to one embodiment of the present invention is arranged along a welded portion 11a of a stainless steel plate 11 which is an example of a material to be welded and has a suction cup 11b. The long thin base material 12 which has, the guide rail 13 attached to the thin base material 12, and the carriage 14 provided on the guide rail 13 and movable in the Z direction.
A welding torch 15 attached to the trolley 14, a wire supply device 17 for supplying a pair of wires 16 which is a filler material attached to the trolley 14, and a thin base material 12 provided on the stainless plate 11. It is provided with electric chain blocks 18 and 18a for suspending and a control device 19.

As shown in FIG. 3, both side edges of the guide rail 13 are wheel contact surfaces inclined at 45 degrees, and four wheels provided on the carriage 14 are provided on these wheel contact surfaces. Abutted. In order to ensure the contact of the wheels,
A wheel pressing mechanism 20 is provided on one side of the guide rail 13. Further, a rack 21 is provided on one side of the guide rail 13, and the rack 21 has a first motor 22 which is a first drive means arranged in the carriage 14 as shown in FIG. The pinion 23 fixed to the output shaft 22a of the vehicle meshes with each other, and by driving the first motor 22, the carriage 14 moves in the Z direction along the guide rail 13.

Further, as shown in FIG. 3, a second welding torch 15 for moving the welding torch 15 in the X direction is provided on the central portion of the carriage 14.
An X-direction moving mechanism 25 having a second motor 24, which is an example of a driving unit of the above, is provided. Torch lateral movement mechanism 2
A Y-direction moving mechanism 27 having a third motor 26, which is an example of a third driving means for moving the welding torch 15 in the Y direction, is provided at the tip of the No. 5. By driving the first and second motors 22 and 24, the carriage 14 moves in the Z direction, the welding torch 15 moves in the X direction, and the weaving of the welding torch 15 is performed. In addition, the third motor 2
By driving 6 to move the welding torch 15 in the Y direction, the distance from the welded portion 11a to the welding torch 15 is kept within a certain range, whereby the arc length during welding can be controlled within a certain range. The first to third motors 22,
24 and 26 include encoders 22b, 24a, and
26a is provided. Next, the wire supply device 17 will be described in detail with reference to FIGS.

As shown in FIGS. 2 and 4, the wire feeding device 1
The wire feeding unit 7 has a pair of supply reels 28 provided on both sides of the rear end of the carriage 14 and a feed motor 30, and is attached to both sides of the front end of the carriage 14 via a plate member 29. 31 and a wire feeding tip 33 arranged below the welding torch 15 via an arm 32 attached to the front end of the carriage 14. The wire feeding section 31 is operated by the feed motor 30, and the wire 16 wound around the supply reel 28 is fed to the wire feeding tip 33 at a preset speed. Next, the control device 19 of the automatic TIG multi-layer device 10 will be described in detail with reference to the block diagram of FIG.

As shown in FIG. 5, the control device 19 includes a control unit 34 having a built-in personal computer, first to third motors 22,
It has three amplifiers 35 for amplifying the current of the drive command to 24 and 26, and a keyboard 36 for inputting welding conditions, and the controller 34 detects the arc voltage during welding and detects the third voltage. An arc length control means for controlling the arc length within a certain range by moving the welding torch 15 in the Y direction by the motor 22 and the first and second motors 24, 26 are driven to move the welding torch 15 to the welding portion 11a. A groove surface detecting means for weaving the groove surface and detecting the position of the groove surface that has passed through both corners of the groove bottom surface of the welded portion 11a by a predetermined width from the change in the arc voltage during the welding of the first layer is detected. The center line calculating means for calculating the center line of the welded portion from the groove surface position and the weaving of the welding torch based on the calculated center line by the previously input numerical value to perform the welding of the second and subsequent layers. Center line reference melting It has deployed the means.

In the control unit 19, the keyboard 36
Welding conditions are input from the control unit 34 to the control unit 34, and drive command currents amplified by the amplifiers 35 from the control unit 34 based on the input data are supplied to the first to third motors 22 and 2.
4, 26, and these motors 22, 2
Encoders 22b, 24a, 26 directly connected to
While the weaving while inputting the output value of a into the control unit 34 to judge its position, the welding torch 15 welds the welded portion 11a, and the Y-direction moving mechanism 27 keeps the arc length during welding constant. Control in range. Also,
In addition to the above, the control unit 34 includes a welding power source 37, an electromagnetic valve 39 for supplying the argon gas (hereinafter, referred to as Ar gas) from the gas cylinder 38 to the welding torch 15, and the supply reel 28 by increasing or decreasing the rotation speed of the feed motor 30. Wire 1 wound around
6 is connected to a wire supply control unit 40 for controlling the feeding of the welding No. 6 and controls the supply of voltage for arc welding to the welding torch 15 and the stainless steel plate 11 by the welding power source 37 and the supply of Ar gas to the welding torch 15. It also controls.

Next, the automatic TIG according to the embodiment of the present invention.
An automatic TIG multi-layer welding method using the multi-layer welding device 10 will be described. As shown in FIG. 1, the thin base material 12 is suspended near the welded portion 11a of the stainless steel plate 11 by the electric chain blocks 18 and 18a, and the position is corrected so that the welded portion 11a and the guide rail 13 are substantially parallel to each other. Then, the thin base material 12 is fixed to the stainless steel plate 11 using the suction cup 11b. Next, the control of the controller 34 will be described in detail with reference to the flowcharts of FIGS. 6 and 7 and the graph of FIG.

First, the setting value necessary for welding such as a temporary weaving width (however, weaving about twice as large as this setting width is possible) WW ', voltage change amount VV, etc., which will be described later, is given to the control unit 34 by the keyboard 36. Enter. Then, as shown in FIGS. 6 and 8, the start button of the automatic TIG multi-layer welding apparatus 10 is pressed. In step 101, the solenoid valve 3
9 to open and weld Ar gas from gas cylinder 38 torch 1
The preflow to be supplied to No. 5 is performed. The voltage change amount VV
Is a voltage change amount that sets how much the arc voltage decreases from the voltage value VC at the center of the weaving to detect the left and right ends of the weaving.

Next, in step 102, the welding torch 15 is lowered by the third motor 26, and the torch 1
The tip of 5 is brought into contact with the surface of the welded portion 11a to generate a touch current. Next, in step 103, it is confirmed that the welding machine has generated an arc by detecting the touch current, and the welding torch 15 is raised by 1 mm in the Y direction by the third motor 26 (step 104). then,
In step 105, a preset initial current is output to the welding torch (see polygonal line a in FIG. 8), and the third motor 26 causes the welding torch 15 to move in the Y-axis direction up to a preset height from the groove bottom surface. And the arc length corresponding to the length from the surface of the groove to the tip of the welding torch 15 is set, and the traveling of the carriage 14 by the first motor 22 is started (see also the broken line b in FIG. 8).

Next, at step 106, the current is gradually increased (see the broken line a in FIG. 8).
At this time, the first and second motors 22 and 24 are driven to gradually weave the welding torch 15 (the broken line c in FIG. 8).
reference). Then, in step 107, when the current reaches the set value, the current continues to flow, and in step 108, welding of the welded portion 11a is started while supplying the wire 16 wound around the supply reel 28 by the feed motor 30 (( (See polygonal lines ad in FIG. 8). The welding torch 1
The weaving of No. 5 reached the set speed before the slow-up was completed (see the broken line c in FIG. 8).

When the stop push button 109 is pressed after the welding of the welded portion 11a is completed, the arc current gradually slows down to prevent welding cracks as shown in step 110, and the weaving of the welding torch 15 also slows down. It goes down (see the broken line c in FIG. 8), and the supply of the wire 16 is stopped (see the broken line d in FIG. 8). However, trolley 14
The running state of No. continues (see the broken line b in FIG. 8). Next, in step 110, a crater process is performed on the weld end, in step 111 the supply of the arc current is stopped (see broken line a in FIG. 8), and the carriage 14 is stopped (see broken line b in FIG. 8) to perform welding. The weaving of the torch 15 is also stopped (see the broken line c in FIG. 8).

After that, in step 112, an after flow for continuing the supply of the Ar gas to the welding torch 15 for a predetermined time is performed, the electromagnetic valve 39 is closed, and the supply of the Ar gas from the gas cylinder 38 to the welding torch 15 is stopped. Here, referring to the flowchart of FIG.
The control by the control unit 34 during the welding of No. 8 will be described in detail.

In step 201, the welding torch 15 is weaved 5 to 6 times based on the set temporary weaving width WW ', and in step 202,
Arc voltage V at the left end, center, and right end of the weaving
The average value of L, VC, and VR is stored in the control unit 34. Then, in step 203, the weaving width WW '
Welding of the first layer is performed while weaving based on. At this time, in step 204, the arc voltage Va during welding is measured.

In step 205, the welding torch 15
Detects the arc voltage while moving to the left, Va ≦
It is determined whether or not it becomes VC-VV. At this time, since the welding torch 15 is out of the center position of the welded portion 11a, the arc length is not controlled by detecting the arc voltage. In step 206, Va ≦
The control unit 3 sets the X direction position of the left end of the welding torch 15 when it becomes VC-VV as the left end position XL of the weaving.
The x and y coordinates are stored in 4.

In step 207, the welding torch 15
Detects the arc voltage while moving to the right, Va ≦
It is determined whether or not it becomes VC-VV. Step 208
In X, the position of the right end of the welding torch 15 in the X direction when Va ≦ VC−VV is the right end position XR of the weaving.
Then, the x and y coordinates are stored in the control unit 34. In step 209, the measured weaving width WW is calculated from the width between the left end position XL and the right end position XR.

In step 210, the control unit 34 controls the first motor 22 based on the weaving width WW to control the moving speed of the carriage 14 in the Z direction so that the thickness of the welding is constant. . In step 211, the center line calculation means of the control unit 34 connects the midpoint XC between the detected left end position XL and right end position XR to calculate the weaving center line CL. Step two
At 12, when the welding of the first layer is completed in this way, the welding of the second layer and thereafter is performed by the center line reference welding means of the control unit 34 with the center line CL as the center of the weaving. Welding is performed by weaving the welding torch 15 by the numerical value (weaving width) input for.

As described above, the groove surface positions XL and XR which have passed the both corners of the groove bottom surface of the welded portion 11a by the predetermined width are detected from the change of the arc voltage during the welding of the first layer, and are detected. Center line CL of welded portion 11a from groove surface positions XL and XR
Then, the welding torch 15 is weaved on the basis of the calculated center line CL to perform the welding of the second and subsequent layers.
It is possible to save time such as positioning of the welding torch 15 and perform welding without failure.

The present invention is not limited to this embodiment, and any change in design within the scope of the invention is included in the present invention. For example, in the embodiment, each time the welding torch moves to the left and right and weaves, an opening that passes through both corners of the groove bottom surface of the welded portion by a predetermined width from the change of the arc voltage at the time of welding the first layer. Although the center line of the welded portion is calculated by obtaining the front face position, the present invention is not limited to this, and the center line may be obtained from two or more groove face positions. Further, in the above-mentioned embodiment, the welding line is a vertical welding in which the welding line is vertical, but the present invention can be applied to the welding in which the welding line is horizontal or inclined.

[0027]

In the automatic TIG multi-layer welding method and apparatus according to the first and second aspects, both corners of the groove bottom surface of the welded portion are separated by a predetermined width from the change of the arc voltage during the welding of the first layer. The position of the groove surface that has passed is detected, the center line of the weld is calculated from the detected groove surface position, and then the welding torch is weaved based on the calculated center line while welding the second and subsequent layers. Since this is performed, it is possible to automatically follow the welding lines of the second and later welding torches. Therefore, it is not necessary to accurately set the guide rails of the carriage along the welding line, and welding can be performed extremely easily. In addition, even if the welding line is slightly curved, T
Since IG welding is performed, the welding work can be saved and the welding time can be shortened.

[Brief description of drawings]

FIG. 1 is a perspective view showing a use state of an automatic TIG multi-layer welding apparatus according to an embodiment of the present invention.

FIG. 2 is a front view of the same.

FIG. 3 is a bottom view of the same.

FIG. 4 is a side view of the same.

FIG. 5 is a block diagram of a control device of the automatic TIG multi-layer welding apparatus according to the embodiment.

6 is an overall flowchart of the control device of FIG.

7 is a flow chart of the main parts of the control device of FIG.

FIG. 8 is a graph showing control over time by the control unit of FIG.

[Explanation of symbols]

 10 Automatic TIG Multi-Layer Welding Device 11 Stainless Steel Plate 11a Welding Part 11b Sucker 12 Thin Base Material 13 Guide Rail 14 Truck 15 Welding Torch 16 Wire 17 Wire Supply Device 18 Electric Chain Block 18a Electric Chain Block 19 Control Device 20 Wheel Pressing Mechanism 21 Rack 22 1st motor (1st drive means) 22a Output shaft 22b Encoder 23 Pinion 24 2nd motor (2nd drive means) 24 Encoder 25 Torch lateral movement mechanism 26 3rd motor (3rd drive means) ) 26 Encoder 27 Y-direction moving mechanism 28 Supply reel 29 Plate material 30 Feed motor 31 Wire feeding section 32 Arm 33 Wire feeding tip 34 Control section 35 Amplifier 36 Keyboard 37 Welding power source 38 Gas cylinder 39 Solenoid valve 40 Wire supply control section

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masataka Ikeda 1-1, Tsukiji-cho, Yawatanishi-ku, Kitakyushu, Fukuoka Prefecture Takada Industry Co., Ltd. (72) Hideyuki Kono 1-1, Tsukiji-cho, Hachimansai-ku, Kitakyushu, Fukuoka Takada Industry Co., Ltd. (72) Inventor Toshio Anzai 1-1 Tsukiji-cho, Hachimansai-ku, Kitakyushu, Fukuoka Prefecture Takada Industry Co., Ltd. (72) In Yasuto Tomonaga 1-1, Tsukiji-cho, Hachiman-nishi-ku, Kitakyushu, Fukuoka Takada Industry Co., Ltd.

Claims (2)

[Claims] 1. A welding torch attached to a carriage having a first drive means for moving in a length direction of a guide rail arranged along a welded portion of a material to be welded, the welding torch being the first Welding of the first layer is performed by weaving the driving means and the second driving means that moves the welding torch in the width direction of the guide rail, and the first layer welding is performed. The position of the groove surface that has passed both corners of the groove bottom surface of the welded portion by a predetermined width is detected, the center line of the welded portion is calculated from the detected groove surface position, and the calculated center line is used as a reference. An automatic TIG multi-layer welding method, wherein the second and subsequent layers are welded while weaving the welding torch. 2. A dolly having a first drive means and moving in the length direction of the rail on a guide rail arranged along the welded portion of the material to be welded, and a welding torch attached to the dolly. A second driving means for moving the welding torch in the width direction of the guide rail, a third driving means for moving the welding torch in the thickness direction of the guide rail, and the first to third driving means. Automatic TIG with control device
A multi-layer welding apparatus, wherein the control device detects an arc voltage during welding and moves the welding torch in the thickness direction of the guide rail by the third driving means to keep the arc length constant. Arc length control means for controlling the range and the first and second driving means to drive the welding torch with respect to the welded portion of the workpiece, and the arc voltage at the time of welding the first layer. And a groove face detecting means for detecting a groove face position that has passed through both corners of the groove bottom face of the welded portion by a predetermined width, and a center line of the welded portion is calculated from the detected groove face position. Center line calculating means, and center line reference welding means for weaving the welding torch by a pre-input numerical value based on the calculated center line to perform welding of the second and subsequent layers. TIG multi-layer welding apparatus.