JPH05185240A - Seam welding equipment - Google Patents

Abstract

PURPOSE:To determine and evaluate the welding quality directly after welding by providing rolls to crush a seam-welded weld zone, a detection means to detect a shift for the welding finished thickness of these rolls and an evaluating means to execute valuation based on this detected information. CONSTITUTION:The rear end of a preceding strip 1 and the tip of a succeeding strip 2 are cut by a shearing machine, respectively, the cut ends of both strips are superposed on each other and seam welding is performed along the superposed part thereof. The seam welding equipment is provided with the swaging rolls 12 to crush the seam-welded weld zone, the detection means 19 to detect these rolls following the welding finished thickness and shifting and the evaluating means 20 to evaluate the welding quality based on the detected information. Consequently, the welding quality is determined and evaluated directly after welding and a finished state of welding and welding abnormality and detected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seam welding device for seam welding a trailing end of a leading strip and a leading end of a trailing strip.

[0002]

2. Description of the Related Art FIG. 3 (a) is a view for explaining the outline of a seam welding apparatus used in a steel process line,
FIG. 3B is a detailed view of the carriage portion. As shown in the figure, the seam welding device is provided to connect the leading strip 1 and the trailing strip 2 (or 2a) to continuously pass the steel in the processing device of the steel process line. In FIG. 3 (a), the upper strip 2a and the lower strip 2 are attached to the trailing strip.
There is a configuration example in which the connection time between the strips is shortened.

The structure of a conventional seam welding apparatus is shown in FIG.
This will be described with reference to (a) and (b). An input side clamp 4 and an output side clamp 5 are mounted on the common base 3, and a carriage 6 is arranged between the both clamps. The carriage 6 is moved by a carriage driving device 7 using a guide mechanism (not shown) installed on the common base 3 as a guide.

The carriage 6 has a guillotine shear 8 for cutting a strip, an electrode 9 for welding, a secondary conductor 10 for supplying a welding current, a welding transformer 11, and a rear portion of the electrode 9. A swaging roll 12 for positioning and rolling the finished part is mounted.

Next, the operation will be described with reference to FIGS. First, as shown in FIG. 4 (a), after the trailing end of the leading strip 1 and the leading end of the trailing strip 2 stop at the center of the guillotine shear 8 (within the double-cut shear tooth width), The strips are clamped and restrained by the output side clamps 5, respectively, and the guillotine shear 8 cuts the trailing end of the preceding strip 1 and the leading end of the following strip 2.

Next, as shown in FIG. 4B, the cut leading strip 1 is slightly tilted upward by the output side clamp 5, and the trailing strip 2 is indexed (advanced) by the input side clamp 4 to be indexed. When is completed, the output side clamp 5 returns the tilting to the original state, and the superposing operation is completed.

The overlapping portion is seam welded by the electrode 9 as shown in FIG. 4 (c). The welding method is as follows: The overlapping portions of the strips are pressed by the upper and lower electrodes 9 supplying a welding current from the welding transformer 11 shown in FIG. 3 via the secondary conductor 10, and the electrodes 9 are driven by the carriage driving device 7. The carriage 6 is rotated along with the carriage 6 while being moved.

As shown in FIG. 4 (d), the welded portion is the electrode 9
Crush it with a swaging roll 12 located at the rear of the to finish it flat. After the completion of swaging (crushing work), the inlet side clamp 4 and the outlet side clamp 5 are released to start passing the line.

FIG. 5 shows a swaging condition, in which t represents the thickness of strips 1 and 2,
T indicates the thickness of the finished weld.

As described above, in the case of seam welding, particularly mash seam welding, since the welding is performed while crushing the overlapped portion, a side force in the line direction, that is, a force in the direction of increasing the clamp interval acts. This force gradually increases as the electrode progresses from the welding start end to the welding end, and becomes maximum at the welding end. As a result, it works as a force that changes the overlap margin at the welding start end and the welding end. Although various considerations have been made in terms of structure so that the overlap margin does not change due to such a phenomenon, the overlap margin often changes and welding defects occur.

The causes of the abnormality in the welded part are: When the overlap margin changes due to the side force in the line direction described above. Besides, b. Insufficient penetration (such as when welding current is too low) or too much strip overlap, resulting in a welding thickness T that is greater than the thickness during normal welding relative to the plate thickness t. C. Excessive penetration (eg when welding current flows too much)
Or the strip overlap margin is too small, resulting in plate thickness t
On the other hand, when the weld thickness T is smaller than that during normal welding.
(In an extreme case, t = T when the strip escapes and the overlap margin becomes 0).

[0012]

The conventional seam welding apparatus is constructed as described above, and if the swaging after welding is completed, the line threading is started. I didn't have the proper means to easily detect the anomaly. For this reason, there is a problem that defective welding products are passed through the plate and disturb the line.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a seam welding device capable of detecting a welding abnormality by judging and evaluating the quality of welding immediately after welding. ..

[0014]

SUMMARY OF THE INVENTION A seam welding apparatus according to the present invention comprises a swaging roll for crushing a welded portion welded by an electrode, and a detecting means for detecting the displacement of the roll following the welding finish thickness. And an evaluation means for evaluating based on the detected information.

Further, a roll which is displaced in accordance with the finished thickness of the welded portion welded by the electrode and a detection means for detecting the displacement of the roll are provided, and an evaluation means for evaluating based on the detected information is provided. Is.

[0016]

The seam welding apparatus according to the present invention continuously detects the finished thickness of the welded portion by detecting the displacement of the roll arranged behind the welding electrode, which serves as a reference under the conditions. Welds are evaluated by comparison with the data.

[0017]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of a swaging roll portion of a seam welding apparatus according to the present invention, showing a state during swaging. The line threading direction is from right to left in the figure,
The swaging roll moves in the direction perpendicular to the paper surface. The mechanism other than the swaging roll portion and the welding procedure are the same as in the conventional example, and thus the description thereof is omitted.

As shown in FIG. 1, the swaging roll 12
Consists of lower roll 13 and pressing roll 14,
13 is attached to the carriage 6 and the level of the upper surface of the roll is matched with the lower level of the strips 1 and 2.
The pressing roll 14 has a structure in which a fluid cylinder 15 attached to the carriage 6 presses the welded portion via a guide shaft 17. A guide 18 is provided to smooth the movement of the guide shaft 17. The displacement of the guide shaft 17 is detected by the detector 19, and this detection information is input to the evaluation means 20 in the control device (not shown).

Next, the operation will be described. Upper and lower electrodes (not shown), lower roll 13, pressing roll 14 during welding
Touches strips 1 or 2. Then, it travels between the front and rear clamps, reaches the welding end, and when the end is detected, the electrode upper part and the pressing roll 14 rise. Therefore, since the pressing roll 14 is displaced vertically while following the welding finish thickness while traveling, the guide shaft that interlocks with it
If the displacement of 17 is detected, the thickness of the finished weld can be measured continuously and reliably. The detected displacement information, that is, the welding finish thickness information is input to the evaluation means 20.

FIG. 2 shows an example of a welding quality evaluation flow in the evaluation means 20. In advance, the relationship between the weld finish thickness and the welding quality of each target welding target material is grasped by inspection and verification, and it is stored in the database 21. For example, it is data of the relationship between the welding finish thickness and the change rate of the finish thickness between the welding start end and the welding end (welding finish thickness change rate) such as the overlap margin, the welding current, the welding speed, and the clamping force. ..

First, the comparison unit 22 compares the detection information from the detector, that is, the welding finish thickness information with the data stored in the database 21 under the condition.

Next, the judging unit 23 judges and evaluates. At 23a, the absolute evaluation of the finished thickness is carried out to judge whether the welding quality is good or bad mainly due to the excess or deficiency of the welding current and the size of the overlap margin. In the case of, the defect factor is estimated. In step 23b, the rate of change in the finished thickness is evaluated to judge the quality of the welding quality, which is mainly due to equipment such as a defective clamp or defective index, and if it is defective, the cause of the defect is estimated.

As a result of the judgment and evaluation made by the judging section 23, if the welding quality is appropriate, an instruction to start striping is issued, and if the welding quality is abnormal, the failure factor previously estimated on the display section 24 is displayed abnormally. To do.

The welding quality information can be fed back to a control device (not shown) and used for controlling the welding current, welding speed, index amount and the like.

Example 2. In the above-mentioned embodiment, the displacement of the swaging roll 12 is detected to detect the welding finish thickness, but in this embodiment, a measuring roll located behind the electrode and displaced following the welding finish thickness is provided. A detecting means for detecting the displacement and an evaluating means for evaluating based on the detected information are provided. If the swaging roll 12 of the first embodiment is replaced with a measuring roll, the configuration and operation are the same, so the description thereof is omitted. However, since the measuring roll does not have a swaging action, its size, strength, etc. may be smaller than that of the swaging roll 12, and the pressure cylinder part may be a simple one, for example, a spring or the like may be substituted. it can.

[0026]

As described above, according to the present invention, the welding finish thickness is detected and the welding quality is evaluated based on the information. Therefore, the welding quality can be judged and evaluated immediately after the welding. It has the effect of being able to detect the finished state and welding abnormalities.

[Brief description of drawings]

FIG. 1 is a sectional view of a swaging roll portion of a seam welding apparatus according to an embodiment of the present invention.

FIG. 2 is a flow chart of an evaluation unit of the seam welding apparatus according to the embodiment of the present invention.

3A and 3B are perspective views showing a seam welding device in a steel process line.

4A to 4D are operation explanatory views of the mash seam welding apparatus.

FIG. 5 is a diagram showing a swaging state.

[Explanation of symbols]

 1 Leading strip 2 Trailing strip 4 Inlet side clamp 5 Outer side clamp 8 Guillotine shear 9 Electrode 12 Swaging roll 19 Detector 20 Evaluation means

Claims (2)

[Claims] 1. A seam welding apparatus for cutting a rear end of a preceding strip and a front end of a following strip with a shear, superposing cut ends of both strips, and performing seam welding along the overlapping portion. A seam characterized by comprising a roll for crushing a seam-welded welded portion, a detection means for detecting a displacement of the roll with respect to a welding finish thickness, and an evaluation means for evaluating based on the detected information. Welding equipment. 2. A seam welding apparatus for cutting the rear end of a preceding strip and the front end of a trailing strip with a shear, superposing the cut ends of both strips, and performing seam welding along the overlapping portion. A seam welding apparatus comprising: a roll that is displaced in accordance with a finished thickness of a welded portion, a detection unit that detects the displacement of the roll, and an evaluation unit that evaluates based on the detected information.