JP3176838B2 - Equipment for manufacturing welded H-section steel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention provides manufacture of welded H-shaped steel
Relates equipment relates manufactured ZoSo location suitable welding H-shaped steel to a temperature matching in particular welding point of the flange material and the web material.

[0002]

2. Description of the Related Art FIG. 3 is a side view of a main portion near a welding point showing a general method for manufacturing a welded H-section steel. The pair of pinch rolls 2 apply a rolling force to press the flange material 3 and the web material 4, which are components of the welded H-section steel 1, against each other, and convey them to the left.

A current is applied to the flange member 3 and the web member 4 by a voltage applied from a high-frequency power source 6 through a contact 5 slidably contacting the flange member 3 and the web member 4. The electric current generates Joule heat as it passes through the flange material 3 and the web material 4 and heats them, and at the same time, they flow intensively at the welding points 7 where they come into contact with each other to melt this portion. Therefore, the flange material 3 and the web material 4 are pressed down by the pinch roll 2 at the welding point 7 where they are in a molten state, and are welded and joined. Reference numeral 8 denotes a power supply cable for connecting the high-frequency power supply 6 and the contact 5, which is insulated.

The reason why a high-frequency power source is adopted as a welding power source for welding an H-section steel is that a high-frequency current is applied to an extremely narrow portion (upper and lower end surfaces of the web material and the end surface of the web material of the flange material) necessary for welding a member to be welded. (A central portion of the width of the steel sheet) to be effectively heated and melted.

[0005] In the case of a welded H-section steel, the flange material and the web material to be welded are different in size, and the temperature of the flange material is generally hard to rise because the thickness of the flange material is larger. Further, the flange material is heated in the width direction because the central portion is heated, whereas the web material is heated at the upper and lower end portions of the width, so that the heat is relatively difficult to escape. For this reason, it is difficult to make the two temperatures match at the welding point, resulting in insufficient heating of the flange material or overheating of the web material, which in turn results in poor welding and insufficient strength of the welded portion of the welded H-section steel.

In order to solve this problem, a preheating auxiliary means for strengthening preheating by supplying a current other than this current near the current path in the flange material is additionally provided with the welding machine, whereby the flange material is provided. There has been proposed a technique for generating Joule heat larger than that of a web material so as to match the temperatures of the flange material and the web material at a welding point. For example, Japanese Unexamined Patent Publication No. 62-199274 discloses a preheating table as such a preheating auxiliary means for flowing an induced current near a welded portion of a flange material.

However, even in this case, when the size difference between the flange material and the web material is large, it has not yet been possible to completely eliminate the temperature difference between the welding points of the two.

[0008]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a welding method which can further enhance the preheating of the flange material and can eliminate the temperature difference between the flange material and the web material at the welding point even when the size difference is large. and to provide a manufacturing ZoSo location of H-section steel.

[0009]

[0010]

According to the present invention, there is provided a pinch roll for feeding a flange material and a web material while pressing the flange material and a web material at a welded portion, and a flange material and a web material which are closer to a welding point which is a pressed portion. One end is connected to each of the first and second contacts that can slidably contact the flange material and the web material at the position of the V seam formed therebetween, and the first and second contacts, respectively. In a manufacturing apparatus for a welded H-section steel having first and second power supply cables and a high-frequency power supply for supplying power to the other ends of the first and second power supply cables from opposite poles, respectively, The first contact is located farther than the second contact, and the first power supply cable is arranged at a short distance from the first contact to the welding point along the welded portion of the flange material , V
V-shaped angle between the flange material and the web material forming the seam
The apparatus for manufacturing a welded H-section steel is provided with a V-section angle adjusting means capable of adjusting the angle .

In the present invention, the contact of the flange material (first contact) with respect to the welding point is replaced with the contact of the web material (second contact).
The preheating time of the welded portion of the flange material that is difficult to preheat is longer than the preheating time of the web material that is likely to be preheated, and the temperature difference between the flange material and the web material at the welding point is reduced. It is easier to resolve. Further, a power supply cable (first power supply cable) connected to the contact (first contact) of the flange material is connected to the welded portion of the flange material (the current path at the center of the width) from the contact to the vicinity of the welding point. Because the arrangement is made so that the currents flow in opposite directions, a proximity effect acts between the welded portion of the flange material and the first power supply cable, and the induced current is superimposed on the welded portion of the flange material. As a result, even if the size difference between the flange material and the web material is large, the temperature difference between the two at the welding point can be effectively eliminated.

The proximity effect is a property that a high-frequency current induces a current in a direction opposite to the facing surface, that is, a current having a phase difference of 180 °, by electromagnetic induction. Since the strength of the magnetic field created by the current wire element at a distance r is inversely proportional to r ² , the proximity effect is more significant as the opposing surface is closer. ("Welding and Joining Handbook" edited by The Japan Welding Society, published on September 30, 1990, Maruzen, p.422
See) Further, Oite this onset Ming, can adjust the flange material and the V shape angle formed between the web material forming the front Symbol V seam V
Since as comprising a shape angle adjusting means, the temperature matching between the flange member and the web material at the weld point is further facilitated.

[0013]

FIG. 1 is an external perspective view of an essential part showing an embodiment of the present invention. In FIG. 1, 1 is a welded H-section steel,
2 is a pinch roll, 3 is a flange material, 4 is a web material, 5
Numerals 1 and 52 are contacts of a flange material and a web material (first and second contacts), 6 is a high-frequency power source, 7 is a welding point (pressure contact), and 81 and 82 are first and second power supplies, respectively. cable,
10 is a V seam, 30 and 40 are welded portions of a flange material and a web material, respectively.
Mean bottom.

Since the apparatus for manufacturing the welded H-section steel is arranged vertically symmetrically, only the upper part will be described with reference to FIG. The same can be said for the lower part (A at the end of the code).
Can be read as B). In the present embodiment, the pinch roll 2 for feeding the flange material 3A and the web material 4 while pressing them at the welded portions (30A, 40A), and the flange material 3A and the web material closer to the welding point 7A which is the pressure contact portion. First and second contacts (51A, 52A) which can slidably abut the flange material 3A and the web material 4 at the position of the V seam 10A formed between the first and second V seams 10A.
First and second power supply cables (81A, 82A) each having one end connected to the second contactor (51A, 52A);
In an apparatus for manufacturing a welded H-section steel 1 having a high-frequency power supply 6A for supplying power from opposite poles to the other end of the second power supply cable (81A, 82A), a first contact 51A is connected to a welding point 7A. It is placed farther than the second contact 52A, and the first power supply cable 81A is arranged from the first contact 51A to the vicinity of the welding point 7A so as to follow the welded portion 30A of the flange material 3A at a close distance. I have. This distance can be finely adjusted freely.

The welding point 7A and the first and second contacts (51A,
52A) is the distance between the flange material 3A and the web material 4A.
70-150mm, 100-500mm respectively
Is suitable, and adjustment can be made within this range. Since the power supply cable 81A is brought close to the welded portion 30A and brought from the first contact 51A to the vicinity of the welding point 7A, the first contact 51 is shown in FIG. As described above, it is preferable to make contact with the flange material 3A on the surface not facing the web material 4, but from the viewpoint of the preheating effect, it is more effective to make contact with the flange material 3A on the side facing the web material 4. .

The frequency of the applied high frequency current is 8 to
About 400 kHz is preferable. High frequency current is 6A
A first power supply cable 81A, a first contact 51A, a welding point 7A, a second contact 52A, a second power supply cable 82A, and a high-frequency power supply 6A. The path from the first contact 51A to the welding point 7A to the second contact 52A is shown in FIG.
Is shown by hatching. This hatched area is preheated by high-frequency electric heating and induction heating.

As shown, the first contact 51A along the welded portion 30A of the flange material 3A to the flange preheating section at the welding point 7A are connected to the second contact 52A along the welded portion 40A of the web material 4. ~ Take longer than the web preheating section of welding point 7A,
Moreover, the first power supply cable for the flange preheating section
Because the 81A was placed in parallel at a close distance, the preheating of the flange material, which is less likely to rise in temperature than the web material, was further strengthened by the preheating time extension and the proximity effect, and the temperature of both welded portions at the welding point 7A was reduced by the welding temperature. Tolerance (1500
(± 50 ° C).

Further, the present embodiment is provided with a V-shaped angle adjusting means 20A shown in a side view of a main part of FIG. This is because the flange member 3A is sandwiched between a pair of support rolls 15A from above and below the first contactor 51A, and the pair of support rolls 15A is lifted by an elevating device 16A.
It is configured to be able to move up and down with A. According to the present embodiment, the preferable range of the V-shaped angle is 3 to 6 degrees. Thereby, the proximity effect acting between the welded portions (30A, 40A) of the flange material 3A and the web material 4 near the welding point 7A can be controlled, so that the temperature difference between the two can be more easily eliminated.

[0019]

[Example] When the present invention was applied to a welding H-section steel production line having a minimum size of H100 × 100 × 3.2 × 3.2 and a maximum size of H300 × 150 × 4.5 × 6.0, the defect rate due to preheating failure was 8.2%, which was the conventional value. Was sharply reduced to 0.5%, and the effect of the present invention was clearly exhibited.

[0020]

According to the present invention, in the production of a welded H-section steel, the preheating of the flange material can be further strengthened than before.
Even if the size difference between the flange material and the web material is large,
This has a remarkable effect that the temperature difference between the two at the welding point can be eliminated.

[Brief description of the drawings]

FIG. 1 is an external perspective view of a main part showing an embodiment of the present invention.

FIG. 2 is a side view of a main part of the V-shaped angle adjusting means.

FIG. 3 is a side view of a main part near a welding point, showing a general method for manufacturing a welded H-section steel.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Welded H-section steel 2 Pinch roll 3 Flange material 30 Flange material welded part 4 Web material 40 Web material welded part 5 Contact 51 Flange material contact (first contact) 52 Web material contact (Second contact) 6 High frequency power supply 7 Welding point (pressure contact) 8 Power supply cable 81 First power supply cable 82 Second power supply cable 10 V seam 15 Support roll 16 Lifting device 20 V-shaped angle adjusting means A Upper part B beneath

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B23K 13/04 B23K 13/08 530

Claims (1)

(57) [Claims] 1. A pinch roll for feeding a flange material and a web material while pressing the same at a welded portion, and a V seam formed between the flange material and the web material closer to a welding point which is a pressed portion. First and second contacts that can slidably abut the flange material and the web material at the respective positions, and first and second power supply cables each having one end connected to the first and second contacts, respectively. And a high-frequency power supply for supplying power to the other ends of the first and second power supply cables from opposite poles, respectively, in the apparatus for manufacturing a welded H-section steel, wherein the first contact is formed between the welding point and the second contact. The first power supply cable is located farther than the first contact, and the first power supply cable is arranged at a short distance from the first contact to the vicinity of the welding point and along the welded portion of the flange material.
Equipped with V-shaped angle adjusting means that can adjust the V-shaped angle between the eb material
An apparatus for manufacturing a welded H-section steel.