JPS61286065A - Teaching play-back type piping welding device - Google Patents

Abstract

PURPOSE:To obtain a flat bead by calculating a welding wire feed quantity in accordance with a difference between a torch storage position before welding and a torch position which has been detected in the course of welding, and executing an automatic control. CONSTITUTION:When a driving part is brought to one round on a fixed pipe 205 in order to store a torch position, a position data which has been detected by a position detector is stored in a torch position storage part. After this teaching has been ended, when a start button in a handy operating case 4 is pushed, a stored welding current value is outputted as a target value to a welding power source 3. Also, a welding speed and a wire feed quantity are controlled in accordance with a target value of a feed motor in a running truck 201. In the torch position after several seconds have passed after the start, its height is detected by the position detector, and a difference between the stored torch position and the torch position corresponding to the present position on the inner fixed pipe 205 is calculated and stored in the torch position storage part. Welding is further advanced, the torch position is always detected, and a difference between this position and the stored torch position is calculated. A corrected value against the set value of the wire feed quantity is calculated and it becomes a target value of the wire feed quantity.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention memorizes the torch position before welding, uses a non-consumable electrode, and automatically uses preset welding parameters as target values while feeding the welding wire. This invention relates to a teaching playback type pipe welding device for welding.

[Technical background of the invention and its problems]

Welding of pipes and tubes often involves all-position welding, and in particular, uranami welding is a technically difficult field that requires skilled skills. Particularly in nuclear couplers and chemical plants, there are many pipes that are fixed horizontally, and the pitch between the pipes is small, and there are many parts with narrow mutual spacing, so there is an especially strong demand for automation of this welding. For this reason, various automatic pipe welding devices have been developed. An example of this is shown in FIG.

In the apparatus shown in FIG. 4, welding parameters such as welding current and welding wire feed amount are inputted into a welding parameter setting section 101 using input keys (not shown) in the control device 100, and are stored in a welding parameter storage section 102. be done. In addition, before welding starts, the torch position detected by a position detector (not shown) in the drive unit 2 is determined by the interface 103.
It is stored in the position storage unit 104 through 1--. When a welding start button (not shown) is pressed to start welding, the welding parameters stored in the welding parameter storage section 102 and the torch position data stored in the torch position storage section 104 are transferred to the interface 103.
The target values are sent to the drive section 2 and the welding power source 3 through the reference numeral 2, and welding is performed.

In such automatic pipe welding equipment, defects are prevented by wrapping the welding bead with the starting end at the welding end, but when welding wire is being fed, a convex part may occur on the bead at the lapped part. .

In addition, not only the weld lap portion but also all welded portions may not be able to form a flat bead, resulting in unevenness. The effects of these irregularities appear up to the final layer of welding, and a grinder is required after welding to flatten the bead, so even though welding itself has been automated, subsequent manual work cannot be eliminated. At present, it cannot be said that this process has been automated as a series of processes.

[Purpose of the invention]

The present invention has been made in consideration of the above circumstances, and it is possible to weld fixed pipes in all positions using non-consumable electrodes while feeding the welding wire. It is an object of the present invention to provide a pipe welding device having a welding wire feed control section that can flatten the bead even when the front bead is uneven.

[Summary of the invention]

In order to achieve the above object, the present invention provides a detection means for detecting the torch position during welding, and a welding wire feed according to the deviation between the torch position detected by the detection means and the torch position stored in advance. a storage section that stores a function for calculating the amount; a means for calculating a welding wire feed amount according to the deviation according to the function stored in the storage section; The present invention is characterized in that it includes means for outputting as a.

[Embodiments of the invention] FIG. 3 shows the equipment arrangement of the pipe welding apparatus according to the present invention.

In FIG. 3, a fixed pipe 205 as a pipe to be welded
A guide rail 204 is fixed to the guide rail 204 via a fixing jig 206. A welding carriage 201 carrying a welding torch 202 and a welding wire feeding device 203 runs on this guide rail 204 to perform welding work. Welding power is supplied from the welding power source 3 via the welding torch 202. Memory of torch position, control of torch position, welding current/
The control device 10 controls the welding speed, wire feed amount, etc.
It is carried out by Further, the start and end of torch position memory and the start and end of welding are performed by a switch (not shown) on the hand control box 4.

FIG. 1 shows an example of the configuration of a control device 10 that constitutes the essential part of the present invention. Inside the control device 10, there is a welding parameter setting section 101 for inputting and setting welding parameters such as welding current/speed and welding wire feed rate, and the welding parameters set here are stored in a welding parameter storage section 102. Ru. In addition, the torch position storage unit 104 stores data from the torch position detector 208 in the drive unit 2 to the Δ/D converter 1 at the time of teaching.
09, the digitized torch position data is stored. A central processing unit (CPIJ) is used to control input and readout of welding parameters and torch positions, data calculations, and output of command values to the welding power source 3 and drive unit 2.
) 108 are provided.

The welding power source control circuit 301 in the welding power source 3 is connected to the control device 1
The welding current is controlled using the output value of the D/A converter 105 within 0 as the target value. Further, the control device 10 controls the drive motor 207 in the drive unit 2 by using the set value stored in the welding parameter storage unit 102 as a target value.
and the amplifier 107, or similarly control the drive motor 207 in the drive unit 2 using the value stored in the torch position storage unit 104 as a target value.

FIG. 2 shows the stored contents of the welding parameters 102. This welding parameter storage unit 102 stores the welding current ■, voltage V, speed F1, welding wire feed rate W0, groove shape data, and welding wire feed rate set using the welding parameter setting unit 101 shown in FIG. A constant a is stored to represent a function that determines an increase or decrease in ff1W.

Now, before welding the fixed tube 205, first, in order to memorize the torch position, when the drive section 2 is rotated around the fixed tube 205, the torch position is stored in the torch position storage section 104 as detected by the position detector 208. The position data is A
/D converter 109 and stored. After this teaching is completed, when a start button (not shown) in the hand control box 4 is pressed, the welding current value stored in the welding parameter storage section 102 is outputted to the welding power source 3 as a target value, and the welding current is increased. controlled.

Further, the welding speed and the welding wire feed rate are each controlled according to target values of a feed motor (not shown) in the welding traveling carriage 201. Welding is automatically controlled in this way, and the height zWl of the torch position several seconds after the start is considered to be stable is detected by the position detector, and the previously memorized torch position is fixed. Difference between the current position on the tube 205 and the corresponding torch position Z ΔZo = ZwIl
1-70 is calculated and stored in the torch position storage section 104.

Welding is further progressed, but at this time too, the torch position Z is always welding. is detected, and the difference ΔZn=Zwn-7n from the already stored torch position 2 is calculated. Then, the increase/decrease of ΔZo with respect to ΔZo used as the previous reference = Δ
Zo−ΔZo is calculated, and the current wire feed rate ■ correction value W=Wo−a−L with respect to the wire feed amount setting value Wo.
is calculated, and 1IiII'm is performed using this corrected value W as a new target value for the welding wire feed amount. Note that the difference between the torch position during teaching and the torch position during welding is caused by fluctuations in welding speed, welding voltage, wire feeding speed, etc., and in the case of multi-layer welding, due to unevenness of the bead in the previous layer, etc. It is something.

As described above, according to this embodiment, if the surface shape during welding is different from the surface shape of the weld line in the groove of the welded pipe during teaching, for example, unevenness may be applied to the bead of the previous layer due to multilayer welding. If this is the case, for example, due to the occurrence of an arc, it is possible to obtain a flat bead that is equal to the height of the additional buildup in a stable state of the arc immediately after the start. Since a flat and smooth bead can be obtained throughout, it is possible to omit a grinder operation for shaping the bead after welding, and it is also possible to obtain a bead of high quality.

Next, other embodiments of the present invention will be described.

In this embodiment, first, the torch position storage unit 104
The torch position P along the welding line before welding is stored in the RAM area of
,P,...P, memorize. Thereafter, welding current 1, voltage V, speed F, and welding wire feeding speed W, which are set and stored in advance in the RAM area of welding parameter storage unit 102. Welding is started using target values such as , etc., and automatic control is performed. After the start, an arc is generated, the welding wire is fed, and the torch position (height) Zwl, II when the welding reaches a stable state B (about several seconds after the start) is detected by the position detector 208, Calculate the difference between the value Z and the value Z stored in the torch position storage unit 104, and calculate this as ΔZo=Zw
It is stored in the torch position storage unit 104 as lIl-Zm. Also, the welding wire feed rate ff1W at this time. The remaining thickness ff1H6 at that time is calculated from the groove shape data stored in the welding parameter storage unit 102 and stored in the welding parameter storage unit 102. Next, when the welding progresses to the previous start position and the state for further welding (lap) is reached (the previous torch position storage unit 104
7), detect the torch position and use it in 7. . shall be.

The difference from the corresponding torch position Z stored before welding is calculated and calculated as Δ2 = 2. . −nn Z. Furthermore, the previously stored difference between Δzo and the like is calculated, and this is set as L=ΔZ −ΔZo.

Next, the difference H8-L from the previously stored excess IH is calculated. Since this is considered to be approximately equal to the ideal welding height at the current position, the groove shape data stored in the welding parameter storage section 102 and this ideal welding height H8-
From L, the appropriate welding wire feed amount W at this position
The welding wire feed rate W is calculated and previously set and stored. Instead, automatic control is performed using the current W as the target value. As a result, a welding wire feed rate is achieved in the lap portion such that the lap portion becomes flat, and the lap portion becomes flat. By controlling the welding wire feed rate in this manner, it is possible to eliminate the need for a grinder to remove the protrusion of the welding wire after welding.

(Effects of the Invention) As described above, according to the present invention, the welding wire is It is automatically controlled using the wire feed amount as the target value, so you can
Even in the uneven parts of the trap part, welding end part, temporary attachment part, and front bead, the welding wire feed rate is such that the bead becomes flat. It is possible to provide a teaching playback type piping welding device that can eliminate the occurrence of defects in bead protrusions that require work.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is an explanatory diagram showing the stored contents of the welding parameter storage section in FIG. 1, and FIG. 3 is a diagram showing a teaching playback type pipe welding device according to the present invention FIG. 4 is a block diagram of a conventional pipe welding device. DESCRIPTION OF SYMBOLS 10... Control device, 101... Welding parameter setting part, 102... Welding parameter storage part, 103...
Interface, 104...Torch position storage unit, 1
05.106...D/A converter, 107...Amplifier, 108...Central processing unit, 109...A/D converter, 2...Drive unit, 201...Welding travel Trolley, 2
02... Welding 1 to -chi, 203... Welding wire feeding device, 204... Guide rail, 205... Fixed pipe, 206... Fixing jig, 207... Drive motor, 2
08...Position detector, 3...Welding power source, 301...
- Welding power supply control circuit, 4...hand control box.

Claims (1)

[Claims] 1. Teaching playback type pipe welding in which the torch position is memorized before welding, and a non-consumable electrode is used to automatically weld while feeding the welding wire and using preset welding parameters as target values. The device stores a detection means for detecting the torch position during welding, and a function for calculating the welding wire feed amount according to the deviation between the torch position detected by the detection means and the torch position stored in advance. a storage unit that stores a welding wire, a means for calculating a welding wire feed amount according to the deviation according to a function stored in the storage unit, and a means for outputting the calculation result as a welding wire feed amount target value. This teaching playback type piping welding device is characterized by: 2. The function stored in the storage unit is W_0 for the set and stored welding wire feed rate, W for the corrected welding wire feed rate, and memory for the torch before welding at the point where the arc stabilized after welding started. The torch detection position during welding is Z_w_m, the torch position during welding is Z_w_n, the torch position during welding is Z_w_n, and the arc is stabilized after welding starts.
The torch memory position before welding corresponding to _w_n is Z_n,
Let the constant be a, W=W_0-a{(Z_w_n-Z_
n)-(Z_w_m-Z_m)} The teaching playback type pipe welding device according to claim 1, characterized in that the teaching playback type pipe welding device is represented by the following formula.