JPS5916554B2 - Pipe external vertical joint welding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION 5 The present invention provides a structure in which a plurality of arc welding torches arranged above the pipe to be welded and spaced apart from each other in the direction of the welding line and the pipe to be welded are arranged relative to each other in the longitudinal direction of the pipe. This invention relates to an apparatus for vertically welding the outer surface of a pipe, which performs arc welding in a downward position while moving the pipe vertically.

0- Generally, when forming a pipe by bending a steel plate, it is difficult to make the abutting part of the pipe completely parallel to the axis of the pipe, and the abutting part may form a spiral shape slightly twisted in the same direction. many.

Therefore, when performing welding by moving the welding torch and the pipe to be welded relatively in the longitudinal direction of the pipe, the position to be welded must be in a direction approximately perpendicular to the axis of the pipe (in this specification, this direction is referred to as left or right). direction) changes from moment to moment. Therefore, when welding), the relative position between the arc welding torch and the pipe to be welded must be corrected in the left-right direction.

In addition, the vertical position of the workpiece in the vicinity of each of the plurality of arc welding torches arranged at intervals in the welding direction is not necessarily the same, so as welding progresses, each welding torch and the workpiece It is also necessary to correct the relative position between them in the vertical direction. Therefore, conventional welding equipment of this type is equipped with a vertical position detection device that detects the vertical position of each welding torch with respect to the workpiece, and a horizontal position detection device that detects the horizontal position of the welding line with respect to each welding torch. The positions of the welding torches were adjusted by individually moving each welding torch in the left-right direction and up-down direction according to the detected amount by these detection devices.

In this conventional welding apparatus, the vertical position adjustment of each welding torch can be performed without any problem, but the horizontal position adjustment cannot be performed successfully for the reasons described below. In other words, when a left-right position detection device is provided for each welding torch as described above and the left-right position of each welding torch is individually adjusted according to the detected amount by the detection device, the direction of welding progress Due to the influence of the weld bead formed by the first welding torch, the detection accuracy of the left and right position detection devices placed near the second and subsequent welding torches is significantly reduced. The position sometimes deviated significantly from the weld line. SUMMARY OF THE INVENTION An object of the present invention is to provide an apparatus for vertically welding the outer surface of a pipe, which allows the lateral position of the second and subsequent welding torches to be adjusted with higher accuracy than before.

The present invention provides a plurality of left and right adjusting devices that are provided with movable members that can move in the left and right directions perpendicular to a weld line of a pipe to be welded and are arranged side by side in the direction of the weld line, and the movement of the plurality of left and right adjusters. A left and right drive mechanism with a drive source for moving a member in the left and right direction, a lifting device supported by the moving member of each of the left and right adjusting devices, an arter welding torch and the arc supported by the lifting and lowering members of each of the lifting devices. a vertical position detection device for detecting the vertical position of the welding torch; a vertical position control means for moving the lifting device up and down in accordance with the detection amount of the vertical position detection device; and a horizontal position control device for detecting the horizontal position of the welding line. and a position detecting device, the horizontal position of each arc welding torch is adjusted by controlling the left and right drive mechanism according to the detected amount of the left and right position detecting device, and the arc welding torch and the pipe to be welded are adjusted. In the apparatus of the present invention, the outer surface vertical joint welding apparatus performs downward arc welding by moving the pipes relative to each other in the longitudinal direction of the pipe to be welded, and in the present invention, the left and right position detection device One arc welding torch located at is supported on the supported elevating member, and the left-right position detection device detects the left-right position of the welding line at the unwelded part to be welded.

Then, one drive source of the left and right drive mechanism is controlled in accordance with the detected amount of the left and right position detection device to simultaneously move the plurality of arc welding torches by an equal amount in the left and right direction, thereby positioning each arc welding torch in the left and right position. A lateral position control means for adjusting the welding torches is provided, and welding is performed while the lateral positions of the plurality of welding torches are simultaneously corrected by equal amounts by the control means. As described above, if a left-right position detection device is installed near the first welding torch to detect the left-right position of the weld line in the unwelded part, the left-right position of the weld line can be increased without being affected by the weld bead. Can be detected with precision.

In addition, in general, the distance between the plurality of welding torches in pipe external longitudinal joint welding equipment is not so large, and the weld line is only slightly deviated in one direction with respect to the pipe axis (the weld line meandering). Therefore, if the left and right positions of each welding torch are simultaneously corrected by the same amount based on the left and right positions of the welding line that are accurately detected near the first welding torch, as described above, the second Subsequent deviations of the welding torch from the welding line can be suppressed to a negligible range. Therefore, according to the present invention, all the welding torches can be made to follow each other well, and unlike conventional welding equipment of this type, the second and subsequent welding torches are prevented from being significantly deviated from the welding line. You can eliminate the inconvenience. Embodiments of the present invention will be described below with reference to the drawings.

1 to 3, 1 is a frame body that is moved relative to the workpiece 2 in the XlX2 direction (the axial direction of the tube) in the drawing, and 3 is a frame body that is moved by a follow-up drive source 301 such as an electric motor. 1 member 302 at YlY, which is approximately perpendicular to the welding line 201.
Left and right drive mechanisms that drive in two directions (left and right), 4 and 5
are first and second left-right adjustment devices supported by the first member 302 of the left-right drive mechanism 3 with a gap in the X direction.
The left and right adjustment devices 4 and 5 each include first and second moving members 402 and 502 that are movable in the left and right directions (Y, Y2 directions) substantially perpendicular to the welding line 201, and these moving members 402 and 502. It is equipped with first and second adjustment driving machines 401 and 501 that respectively drive the left and right directions, and these first and second adjustment driving machines 401 and 501 can be rotated or rotated by pressing a push button. The first and second moving members 402 and 50 are moved by direct movement.
The positions of the two can be adjusted individually in the left and right directions. In addition, instead of providing one adjustment drive machine in this way,
The left and right positions of the first and second moving members 402 and 502 may be adjusted using a manual handle. First and second lifting devices 6 and 7 are supported by first and second moving members 402 and 502, respectively, whose positions are adjusted in the left-right direction among the left-right adjustment devices 4 and 5.

The first and second elevating devices each include first and second elevating drive sources (for example, electric motors) 601, 701 and first and second elevating members 602, 702. The first and second elevating members 602, 702 are moved ZlZ2 with respect to the welding line 201 by the drive sources 601, 701.
It is constructed so that it can be raised and lowered in both directions. 8 and 9 are first and second mounting members supported by the first and second elevating members 602 and 702, respectively, and the first and second support members 11 and 12 are welded to these mounting members, respectively. The support members 11 and 12 support first and second arc welding torches 15 and 16, respectively.

13 and 14 are first and second vertical position detection devices attached to the first and second support members 11 and 12.

These detection devices have a rotatable ball at the lower end, and detect changes in the position of the ball in the vertical direction (ZlZ direction) using a differential transformer or limit switch, and use this detection signal to control the vertical position. The vertical distance between the workpiece 2 and the first and second support members 11 and 12 (therefore, the welding torch 15, 16 and the pipe to be welded 2) is maintained constant. 17 is in the left and right direction (
This is a left-right position detecting device that is movably provided in YlY2 directions) and detects the left-right position of the welding line 201 with respect to the arc welding torch in an unwelded part to be welded. Among the welding torches 16, the welding torch 15 is disposed near the leading welding torch 15 in the welding progress direction and supported by the first support member 11.

The lateral position detection device of this embodiment uses a guide roll 17a that fits into the groove of the workpiece 2, and changes in the lateral position (Y, Y direction position) of this guide roll using a differential transformer or a limit switch. and a detector for detection.

Then, by controlling the drive source 301 of the left and right drive mechanism 3 according to the detected amount of the left and right position detector 17, the first and second
A left-right position control means is provided for adjusting the left-right position of the arc welding torches 15 and 16 by simultaneously moving the same amount in the left-right direction, and the control means controls the first and second arc welding torches. Welding is performed while the left and right positions of the welding torches are simultaneously corrected by equal amounts. Next, the operation of the above apparatus will be described assuming that welding is performed in the X1 direction while moving the frame 1 and the workpiece 2 relative to each other in the X direction in FIGS. 1 to 4. In this case, the planned welding line is shown by the XO-XO line, and the actual welding line is shown by the Xw-Xw line (see FIG. 4). Further, the center positions of the first welding torch 15 are indicated by symbols TlO to Tl2, and the center positions of the second welding torch 16 are indicated by symbols T2O to T22. Prior to the start of welding, the first and second support members 11 and 12 are connected to the first and second support members so that the distance between the first welding torch 15 and the second welding torch 16 becomes the desired distance L. placed on mounting members 8 and 9.

Thereafter, by manual operation means such as push button operation or manual handle operation, the moving member 4 of the left and right adjustment devices 4 and 5 is moved.
02,502 in the left and right direction (Y direction),
The positions of the second welding torches 15 and 16 are set at points T, l, and T2 on the welding line (Xw-Xw), respectively.
Next, the elevating drive sources 601 and 701 are operated to lower the elevating members 602 and 702. 1 drive sources 601 and 701 for lifting and lowering are vertical position detection devices 13 and 14
The ball stops at a neutral position (a position where no detection signal is generated) where it touches the surface of the workpiece 2, and at the same time the lifting member 60
2 and 702 are also stopped. In this state, welding is performed in the X direction while the guide roller of the left-right position detection device 17 supported by the first support member 11 is fitted into the groove of the workpiece 2 to be welded. In this case, as shown in Fig. 4, when the welding progresses in the X1 direction by a distance
line) and the actual welding line (Xw-Xw line) are not parallel, so in order to ensure welding, welding torches 15, 1
6 must be moved by ΔY in the Y2 direction. Therefore, in this embodiment, the lateral position of the welding line is detected by a lateral position detection device 17 having a guide roller that fits into the unwelded groove on the welding proceeding side of the workpiece 2, and the lateral position of the weld line is detected according to the detected amount. to drive the tracking drive source 301, and
302 is moved in the Y direction.

Therefore, the first and second welding torches 15 and 16 are
It is simultaneously displaced in the left-right direction (Y direction) together with the member 302 and follows the welding line 201. In this case, the left and right position detection device 17 detects the weld line 2 at the unwelded part to be welded on the side in the welding progress direction.
Since the left and right positions of 01 are detected, the position of the weld line can be detected with high precision without being affected by the weld bead.

When the welding line 201 is displaced by ΔY in the Y direction, the welding torches 15 and 16 are also displaced in the Y direction simultaneously by ΔY by the left and right drive mechanism 3 according to the amount detected by the left and right position detection device 17. , the welding torch will always be located on the actual welding line. When making a pipe by bending a steel plate, the butt part will be slightly inclined in one direction with respect to the axis of the pipe, but since the butt part will hardly meander along the extension line, the weld line will be By simultaneously moving the welding torches, which are spaced apart from each other, in a direction substantially perpendicular to the axis of the pipe, the welding torches can be brought almost in line with the line to be welded, as described above.

Furthermore, since the first and second lifting members 602 and 702 are provided with the first and second vertical position detection devices 13 and 14, respectively, even if the first and second welding torches 15
Even if the vertical position of the welded object differs in the vicinity of
is activated.

Therefore, the first and second lifting members 602 and 702
The second support members 11 and 12 are moved up and down so as to maintain the vertical positions relative to the pipe 2 to be welded in the initial state, thereby keeping the welding torches 15 and 16 always at a constant level with respect to the surface of the pipe 2 to be welded. Position at height. As described above, the welding torch is always positioned on the welding line and at a constant position relative to the surface of the workpiece, so that welding is performed perfectly.

FIG. 5 shows an embodiment in which a servo valve is used as the left-right position detection device 17, and a fluid pressure actuated cylinder is used as the follow-up drive source 301. In this embodiment, when the guide roller 17a is displaced from the neutral position by ΔY in the Y1 direction, the cylinder rod of the fluid pressure actuated cylinder is controlled to protrude by the displacement amount (detected amount) ΔY. Of course, in this case, the fluid-pressure-operated cylinder is no different from a fluid-pressure-operated rotary machine. FIG. 6 shows an embodiment in which the left and right position detection device detects the left and right positions without contacting the workpiece, and in this example, it has two fluid ejection holes 17b, 17b. The fluid detector 17 is placed at the abutting part of the workpiece as shown in the figure, and after the output pressure from both the jet holes is amplified by the pure fluid amplification element 171, the difference between the two amplified output pressures is equalized to the pneumatic pressure. The voltage is converted into a voltage by a voltage converter 172, and this voltage drives a tracking drive source 301 to cause the first member 302, welding torches 15 and 16, and left and right position detector 17 to follow the welding line. ing.

In addition, when a fluid-pressure-operated cylinder or rotary machine is used as the follow-up drive source 301, the pressure fluid can be switched by the voltage converted by the pneumatic-to-voltage converter 172, as shown by the two-dot chain line in FIG. The hydraulic cylinder or rotary machine 301 can be operated by switching the electromagnetic valve 173.

7 and 8 show the case where two sets of left and right drive mechanisms are arranged and each is provided with a following drive source, and the first and second left and right adjusting devices 4 and 5 are each provided with a following drive source. It was installed.

That is, the drive sources 401 and 501 shown in FIG. 1 are used as the follow-up drive sources 301 and 301, and in this case, of course, the drive source 301 and the first member 302 shown in FIG.
is not necessary. In the example shown in FIG. 7, electric motors are used as the drive source for follow-up, and each electric motor is activated simultaneously by detection signals from the left and right position detection devices, but in the case of manual operation, push button switches 181 to 184 are operated. As a result, each electric motor is arbitrarily driven to appropriately adjust the positions of the first and second moving members 402 and 502 in the Y direction. Figure 8 shows 2 drive sources for 1 tracking.
This example shows an example using a set of hydraulically operated cylinders or rotating machines. In this example, when performing left-right copying, both solenoid valves 174 and 175 are in the neutral position (
(closed state), and the copying solenoid valves 175 and 176 are operated so that their passages are mutually opened.

In addition, when manually operating a cylinder or rotating machine operated by fluid pressure, after the copying solenoid valves 175 and 176 are operated so that their passages are closed, the manual adjustment solenoid valves 175 and 176 are operated. The operation is performed by appropriately switching the spools 174 or 175 using push buttons.
In this case, it goes without saying that the manual adjustment solenoid valves 174 and 175 may be manually operated switching valves. FIG. 9 shows an embodiment using a sensor having a non-contact E-shaped core 19. In this embodiment, the central leg of the core 19 has an excitation winding 191 excited by an AC power source 192.
is wound, and the right and left legs each have a detection winding 1.
93 and 194 are wound. If the welding line is now shifted in the Y2 direction and the center leg of the E-shaped core 19 is positioned on the workpiece 2a, a magnetic path consisting of the center leg, the left workpiece 2a, and the left leg of the E-type core will be created. Magnetic resistance is the central leg of the core,
Since it is smaller than the magnetic resistance of the magnetic path consisting of the groove portion of the left workpiece 2a1, the workpiece 2b, and the right outer leg of the E-shaped core, a large amount of magnetic flux passes through the left outer core, and therefore the induced voltage Ea is It becomes larger than Eb. The difference between these voltages Ea - Eb
is supplied to the control device. The control device is the first member 302
, the welding torches 15, 16 and the left and right detection devices 17 are connected to Y2.
An output is supplied to the follow-up drive source 301 so as to move in the direction. If the welding line is shifted in the Y1 direction, the operation opposite to the above is performed. As shown in Figure 2, when the left and right drive mechanisms are configured to be driven by a single drive source, two
There is an advantage that the above welding torches are reliably moved simultaneously. In addition, as shown in Figures 7 and 8, if the left and right drive mechanisms are configured to be driven by the same number of drive sources as the welding torches, a mechanism to synchronize each drive is required, but the left and right drive mechanisms are This is advantageous because the adjusting device and the left/right drive mechanism can be used together.

Of course, in this case automatic and manual operation can be carried out by suitable switching means. In the description of the present invention, the vertical position detection device is a mechanism that does not make contact with the workpiece, for example, a mechanism that injects fluid pressure onto the workpiece and detects the height from the surface of the workpiece based on the back pressure. You can also do that.

Further, three or more welding torches may be provided.

By arranging three or more welding torches in this way, each welding torch can perform a small amount of welding.
It is also possible to reduce the heat input to the workpiece at each welding position, thereby preventing overheating of the workpiece and adverse effects on the metal structure. As described above, according to the present invention, the lateral position detection device is provided on the elevating member supporting the leading welding torch in the welding progress direction, and the lateral position of the weld line is detected in the unwelded part to be welded. , the left and right positions of the weld line can be detected with high precision without being affected by the weld bead, and multiple welding torches can be moved horizontally by the same amount at the same time according to the detected amount of this left and right position detection device. Since the left and right positions of each welding torch are adjusted, all the welding torches can be made to follow the welding line well.

Therefore, there is an advantage that a good welding result can be obtained without the inconvenience caused by the second and subsequent welding torches being largely deviated from the welding line. Furthermore, the structure can be simplified because the left-right position adjusting device only needs to be provided near the leading welding torch. Furthermore, the vertical position of each welding torch can be adjusted without any problem.

[Brief explanation of the drawing]

Fig. 1 is a front view showing an embodiment of the present invention, Fig. 2 is a side view of Fig. 1, Fig. 3 is a plan view of Fig. 2, Fig. 4 is an operation explanatory diagram of Fig. 3, and Fig. 5 9 to 9 are schematic configuration diagrams showing different modifications of the left and right drive mechanisms used in the present invention, respectively. 1... Frame, 2... Welded object, 201
...Welding line, 3... Left and right drive mechanism, 3
01...Following drive source, 4...First left and right adjustment device, 5...Second left and right adjustment device, 6
....First lifting device, 7...Second lifting device, 13...First vertical position detection device, 1
4...Second vertical position detection device, 15...
...First welding torch, 16... Second welding torch, 17... Left and right position detection device.

Claims (1)

[Scope of Claims] 1. A plurality of left and right adjustment devices that are provided with movable members that can move in the left and right directions perpendicular to the weld line of the pipe to be welded and are arranged side by side in the direction of the weld line, and the plurality of left and right adjustment devices. a left-right drive mechanism with a drive source for moving the movable member in the left-right direction, a lifting device supported by the moving member of each of the left-right adjustment devices, and an arc welding torch supported by the lifting member of each of the lifting devices. and a vertical position detection device for detecting the vertical position of the arc welding torch, a vertical position control means for moving the lifting device up and down in accordance with the detection amount of the vertical position detection device, and a vertical position control means for moving the lifting device up and down in accordance with the detected amount of the vertical position detection device, and a left-right position detection device for detecting, and controlling the left-right drive mechanism according to the detected amount of the left-right position detection device to adjust the left-right position of each arc welding torch and the In the external vertical joint welding device for pipes that performs downward arc welding by moving the pipe to be welded relative to the pipe in the longitudinal direction, the left and right position detection device is for arc welding located at the beginning in the welding direction. 1 on the lifting member on which the torch is supported.
The drive source of the left and right drive mechanism is controlled in accordance with the detection amount of the left and right position detection device, and 1. A pipe external vertical joint welding device, characterized in that the apparatus is provided with a left-right position control means for adjusting the left-right position of each arc welding torch by simultaneously moving the arc welding torches in the left-right direction by an equal amount. 2. The outer surface vertical joint welding apparatus for pipes according to claim 1, wherein only one drive source for the left and right drive mechanism is provided in common for the plurality of arc welding torches. 3. The external vertical joint welding apparatus for pipes according to claim 1, wherein a drive source for the left and right drive mechanism is provided individually for each of the arc welding torches.