JPH01271075A - Method and equipment for welding metal strips - Google Patents

Abstract

PURPOSE:To prevent deformation such as wrinkles and strain in welding the title metal strips by pressing either clamp pad of the inlet side and the outlet side clamping devices on a contact part to perform welding in a packed state. CONSTITUTION:A preceding strip 1 and a succeeding strip 2 are fed onto a strip traveling line and both strips 1 and 2 ends are clamped and held respectively by the inlet side clamping device 3 and the outlet side clamping device 4. A movable carriage 5 then starts to move in the direction to cross the strip traveling line by a cylinder 7. Both strips 1 and 2 ends which are clamped and held are cut by an upper blade 18 and a lower blade 19. After cutting is completed, the inlet side clamping device advances and the cutting parts of both preceding and succeeding strips are superposed slightly on each other extending over the overall length of the strip width. Thus, the movable carriage 5 advances and the welding is started while the lap part being crushed by upper and lower electrodes 8 and 9. In this case, the clamp pad 44 is backed up by the lower electrode ring 9 and the upper electrode ring 8 is pressed and welding is performing by carrying high current thereto.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a welding method and apparatus for connecting the trailing end of a leading strip to the leading end of a trailing strip, and more particularly relates to a welding method and apparatus for connecting the trailing end of a leading strip to the leading end of a trailing strip, and more particularly, to The present invention relates to a metal strip welding method and apparatus for welding metal strips while suppressing wrinkles during welding.

BACKGROUND OF THE INVENTION Process lines such as pickling and annealing lines in steel mills commonly use arc welding and laser welding, as well as flash and seam welding, to weld metal strips.

Matush seam welding is generally known as a method of seam welding metal strips.

In this process, the stacked plates are pinched between upper and lower electrode rings, and simultaneously crushed and welded. Generally, the rear end of the leading strip and the tip of the trailing strip are placed relative to each other on the strip running line. After the clamped end of the strip is cut by a shear device, the clamping device is moved to overlap the two ends by the required amount, and the overlapped contact portion is cut. The metal part is sandwiched from the end between an upper electrode ring and a lower electrode ring, applying a strong pressure and a large current, and welding proceeds while the heated and softened metal part is flattened by the electrode ring.

(Problems to be Solved by the Invention) In the case of conventional Manche seam welding, the overlap margin at the end of the strip is generally smaller than the electrode width, and the overlap margin can be sufficiently crushed, and the welding speed is high. It is mentioned as.

However, when welding thin plates, this welding method applies sufficient pressure to form a sufficient crushing margin, and if a difference occurs between the moving speed of the electrode wheel and the rotational peripheral speed of the electrode wheel, , a phenomenon occurs in which the electrode ring pulls the end of the clamped strip, resulting in the formation of fine wrinkles with a wavy cross section over the entire length of the weld.

Therefore, when welding thin plates, it remains a major problem how to eliminate wrinkles and form a sufficient crushing margin.

(Means for Solving the Problems) Therefore, the present invention provides a welding method and device that solves the above problems, and its technical means consists of an entry side clamp device arranged on the running line and an exit side clamp device arranged on the running line. The rear end of the leading strip and the tip of the trailing strip are each clamped and held by a clamp device, the ends of both strips held by the clamp are cut via a shear device, and the cut ends are overlapped. Thereafter, in a metal strip welding method in which the contact portion is softened and joined by heating, the welding is performed in a state in which the clamp pad of one of the clamp devices is pressed against the joint portion and buffed.

In order to carry out the above method, an entry side clamp device and an exit side clamp device that clamp the leading strip and the trailing strip at opposing positions are provided, and both strips are held between the two clamp devices. A shearing device for cutting an end by advancing an upper blade and a lower blade in a direction transverse to a strip running line, a means for overlapping the ends cut by the shearing device by a required amount, and a contact portion of the overlapping. In a seam welding machine having an upper electrode ring and a lower electrode ring which proceed with welding by heating and softening, one of the clamping devices has a bank bar function which is banked up by the electrode ring in addition to the original clamping function. We provide welding equipment with both

(Function) According to the present invention, the clamp pad of the clamping device on either the entry side or the exit side of the metal strip welding device is pressed against the contact portion of both ends of the strip, also serving as a back bar, and the backing is performed. By performing welding in the welding state, even if there is a difference in the moving speed and rotational circumferential speed of the electrode ring during mash seam welding of thin plates, the large gap between both electrodes can be uniformly applied to the welding area via the back bar. Since pressing force can be applied, the weak thin plate workpiece is not pulled by the electrode wheel, and deformation such as wrinkles and distortion can be prevented. Furthermore, it can be easily attached to an existing clamp device by simply changing the material and length of the clamp pad. Also, when cutting the strip, the clamp pad extension can be set back to the same position as the normal clamp pad extension, and after the strip is cut, it can be advanced to a position where the overlapping margin of both strips can be sufficiently backed. Therefore, it can be used for laser welding, arc welding, etc. in addition to seam welding, and it is easy to set welding conditions according to the strip thickness.

(Example) Below, regarding the apparatus for carrying out the welding method of the present invention,
Examples thereof will be described with reference to the drawings.

Fig. 1 schematically shows the overall structure of a metal stripping device consisting of a mash seam welding machine with a built-in rotary shear device, and an entry clamp device and an exit clamp device arranged on the strip running line. FIG. Moreover, FIG. 2 is a schematic front view thereof. Fig. 3 is a front view of main parts showing an embodiment in which a lower clamp pad with a clamp function and a back bar function is fixed to the entry side clamp device, and Fig. 4 is a front view of the main parts of the lower clamp pad having a clamp function and a back bar function. FIG. 2 is a front view of main parts showing an embodiment of an entry side clamp device that can be adjusted arbitrarily.

1 indicates a leading strip, and 2 indicates a trailing strip.

The arrow indicates the direction of travel of the strip running line.

3 is an entry side clamp device, and 4 is an exit side clamp device.

Reference numeral 5 denotes a moving table corresponding to the main body of the C-frame welding machine.

The movable table 5 is guided on rails 6 and is moved forward and backward by a driving source such as a cylinder 7 from a direction perpendicular to the strip running line. Reference numeral 8 denotes an upper electrode ring, and this electrode is supported under a frame 10 which is rotatably supported at the tip of the upper arm 11 of the movable table 5 via the rotation axis P, and is mounted on the tip of the upper arm 11. The cylinder 12 moves up and down together with the frame 10. and frame 1
A pressure cylinder 13 mounted on the electrode provides a large electrode pressure necessary for welding.

Reference numeral 9 denotes a lower electrode ring corresponding to the upper electrode ring 8, which is fixed to the lower arm 14 of the movable table 5 so as to be vertically adjustable.

15 is a rotating rotary shear device for cutting the ends of the metal strip 1.2. This shear device consists of a moving platform 5
A shear frame 17 is equipped with a vertical frame 16 having a vertical frame 16 at the tip of a lower arm 14 so as to be movable in the vertical direction with a cylinder 27, and this shear frame 17 has an upper blade 18 having two rotating blades of a rotary shear type. A lower blade 19 having two rotary blades corresponding thereto is provided.

Note that the shear device may be of a guillotine shear type.

Reference numeral 20 is used to crush the plate thickness of the welded part to a final constant thickness using a reduction roll, and can be equipped as required.

The entry side clamping device 3 and the exit side clamping device 4 are arranged at opposing positions on the strip running line, and clamp stands 23 and 24 are mounted on the upper part of each of the entry and exit side clamp bases 21 and 22. Vertical frames 25.26 and 40.41 are fixed on both sides of the frame, and horizontal frames 28 and 29 are respectively fixed between the vertical frames. And each of the horizontal frames 28 and 29 on the entry side and the exit side,
A clamping cylinder 32,33 is fixed in each case, the piston rod 3 of this clamping cylinder 32,33
At the tips of 4.35, upper clamp beams 36.37 on the entry side and exit side are supported so as to be movable up and down while being guided on both sides.

Lower clamp beams 38 and 39 corresponding to the upper clamp beams 36 and 37 on the entry and exit sides, respectively, are fixed to the respective clamp stands 23 and 24, respectively.

The details of the clamping device will be described below as shown in FIGS. 3 and 4.
Attached to the lower side of 7 are upper clamping pads 42 and 43, respectively, which face the upper side of the metal strip 1.2.

Also on the upper side of each lower clamping beam 38.39 are lower clamping pads 44 and 45 which are in contact with the lower side of the metal strip 1.2 corresponding to the upper clamping pad 42.43.
are each fixed.

The lower clamp puff ρ44 on the entry side shown in FIG. 3 is made of a conductive material, and the tip of the pad is (
As shown in FIG. 5b), the clamp pad tip is longer than the other clamp pad tips to the extent that it does not interfere with the side surface of the lower blade 19.

Lower clamp pad 4 of entry side clamp device 3 shown in FIG.
Reference numeral 4 is a cylinder 46 fixed to the lower crushing beam 38, which is movable in the front and rear directions, and is configured so that the amount of protrusion of the tip of the clamp pad can be adjusted. By doing this, for example, when cutting a strip, it is normally retracted to a distance that matches the extension dimension (e) of the other upper clamp pad 42, and after cutting the strip, the overlapping allowance of both strips can be sufficiently backed. The extension can be extended to the desired position. Therefore, in addition to seam welding, it can also be used as a back bar for laser welding, arc welding, etc.

Although this embodiment describes the case where the lower clamp pad 44 of the entry side clamp device is used together with the back bar, it can be used depending on the purpose, for example, if the direction of applying pressure to the upper electrode ring 8 or the lower electrode ring 9 is taken into consideration. It is also possible to use upper or lower clamp pads on the back bar, either on the entry or exit side.

Next, the operation of the present invention will be explained based on FIGS. 5a to 5d.

First, the rotary shear device 15 is waiting at the original position A-A.

When the leading strip 1 and the trailing strip 2 are fed onto the strip running line in this state, the ends of both strips are clamped and held by the entry side clamping device 3 and the exiting side clamping device 4, respectively. (See Figure 5a).

Next, the moving table 5 starts to be moved by the cylinder 7 in a direction across the strip running line. The ends of both clamped strips are cut by an upper blade 18 and a lower blade 19. In this case, the lower blade 19 enters the front surface of the lower clamp pad 44 of the entry side clamp device 3, and the end of the leading strip 1 is cut at a position equivalent to the length of the lower clamp pad 44 (see Figure 5b). ).

When the cutting is completed, the entry clamp device 3 moves forward to slightly overlap the cut portions of both the leading and trailing strips over the entire width of the board (see Figure 5C).

Thus, the movable table 5 moves forward and welding is started while crushing the overlapping portion with the upper and lower electrode wheels 8.9. In this case, the back bar 44 is backed up by the lower electrode ring 9, pressurizes the upper electrode ring 8, and welds by flowing a large current (see Fig. 5d).

When the welding is complete, both clamping devices 3.4 are opened and the strip is threaded through. Then, the shear device 15 rises again to the strip clamp line and prepares for the next operation.

Although the above embodiment describes an example in which the present invention is applied to matsch seam welding equipped with a rotating rotary shear device, the essence of the present invention is not limited to this. For example, arc welding and laser welding Various applications are possible for welding, etc.

(Effects of the Invention) As described above, according to the method of the present invention, the clamp pad of the clamping device on either the entry side or the exit side of the metal strip welding device can be used to overlap the ends of both strips in addition to the original clamping function. By pressing it against the bank bar and also functioning as a back bar, even if there is a difference in the rotational circumferential speed and moving speed of the electrode ring during mash seam welding of thin metal strips, the strong force between the two electrodes can be maintained through the bank bar. Since it is possible to uniformly apply pressure to the welded part, deformations such as wrinkles and distortion can be prevented. Furthermore, according to the device of the present invention, only the material and length of the lower clamp pad can be changed.
The structure is simple and can be easily retrofitted to existing clamping devices, and the length of the lower clamp pad can be automatically adjusted, allowing welding with sufficient backing of both strips. Moreover, it enjoys many excellent effects such as being able to easily set welding conditions according to the strip thickness.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view showing an example of the basic configuration of a metal strip welding device incorporating a matshu seam welding machine. FIG. 2 is also a schematic front view. FIG. 3 is a schematic front view showing an example of the main part configuration of a clamp device for carrying out the method of the present invention;
The figure is a schematic front view showing another embodiment of the device of the present invention. Chapter 5a
Figures 5 to 5d are explanatory views of the operation of the present invention. (Explanation of symbols)

Claims (1)

[Claims] 1. An entry side clamp device and an exit side clamp device arranged on the running line clamp and hold the rear end of the leading strip and the tip of the trailing strip, respectively, and both strips held by the clamps. In a metal strip welding method in which the ends of the metal strip are cut through a shear device, the cut ends are overlapped, and the contact portions are softened and joined by heating, the clamp of either one of the two clamp devices is used. A metal strip welding method in which welding is performed with the pad pressed against the contact area and backed. 2. An entry side clamp device and an exit side clamp device that clamp the leading strip and the trailing strip at opposite positions, and the ends of both strips held between the clamp devices are moved across the strip running line. a shear device for cutting by advancing an upper blade and a lower blade in a direction; a means for overlapping the ends of both strips cut by the shear device by a required amount; and heating and softening of the overlapping contact portion to perform welding. A seam welding machine having a moving upper electrode wheel and a lower electrode wheel, characterized in that one of the clamping devices has a back bar function backed up by the electrode wheel in addition to the original clamping function. Metal strip welding equipment.