JP3036871B2 - Bar material joining method and apparatus for hot strip rolling - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for joining a bar material for hot strip rolling, in which a preceding bar material and a following bar material are joined before finish rolling in order to continuously finish-roll a hot strip. .

[0002]

2. Description of the Related Art Numerous techniques have been disclosed for joining methods and joining apparatuses for bar materials. A typical example is shown in JP-A-60-40601. In this example, 2
The front and rear ends of the two bar materials are simultaneously cut by two cutting machines provided in the joining machine, and immediately thereafter, the two cut surfaces are pressed by a bar material butting device and joined.

[0003] There is no cutting machine in the joining machine,
When cutting the leading and trailing ends of a bar with two cutting machines, when each bar is passed through the joining machine, two bars are required in the joining machine due to the inclination of the bar and the bending of the end of the bar. It is difficult to abut the cut surfaces of the two bar members in the plate width direction without gaps. Therefore, as disclosed in JP-A-61-165286 or JP-A-59-141302, the abutting of the front and rear end surfaces of the bar material is abandoned, and the leading and trailing ends of both bar materials are abandoned. A method is employed in which the rear ends are overlapped and joined. The superposed members are joined by rolling the overlapped portion in Japanese Patent Application Laid-Open No. Sho 61-165286, and by driving a nail-shaped material into the overlapped portion in Japanese Patent Application Laid-Open No. Sho 59-141302.

[0004]

SUMMARY OF THE INVENTION Japanese Patent Application Laid-Open No. 60-4060
If two cutting machines are provided in the joining machine as shown in Japanese Patent Publication No. 1 (1993), it is possible to very reliably perform the joining of the front and rear end surfaces of the bar material for joining. However, the dimensions of the actual bar material are 30 to 50 mm in thickness, and the maximum plate width is 2,0.
A cutting force of about 1500 tons per machine is required for the cutting of 00 mm. It is not practical to mount two such cutting machines in the joining machine because the equipment becomes extremely large. For this reason, one cutting machine fixedly arranged in front of the finishing mill as in the prior art cuts the end portions of the preceding and succeeding bar materials, and then cuts into the joining machine provided on the next stage. It is desired to transfer the two cut portions and join the two cut end portions by abutting each other. However, 2
Since the two bar materials are transported independently, there is always a slope between the two bar materials, and the leading and trailing ends of the bar materials are often bent, so cutting these two bar materials It is difficult to match the surfaces over the entire surface in the plate width direction. For this reason, abandon the butt joining of the cut surface,
As described above, a method of overlapping and joining the cut portions of two bar materials is employed. However, this overlapping method has a drawback that the rolls are flawed because the amount of rolling in this portion is suddenly increased.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method and an apparatus for joining a bar material for hot strip rolling, which can solve the above-mentioned disadvantages and perform reliable joining.

[0006]

In order to achieve the above object, according to the present invention, one cutting machine, a bar joining machine, and a finishing mill are arranged in this order. Then, one cutting machine cuts the rear end of the preceding bar material and the front end of the following bar material. Then, the ends of the two bar members are transferred into the joining machine, and both end surfaces are abutted. Before performing the butting operation, both bar members are narrow-pressure supported by two clamp devices provided in the joining machine. Then, the clamp device that supports at least one bar member under narrow pressure is brought close to the clamp device that supports the other bar member under narrow pressure by a translational motion while allowing a rotational motion to abut the end surfaces of the two bar members. You.

[0007] The end faces of the two bar members butted in this manner are joined by heating. For heating the bar end face, 2
At least two or more loop-shaped non-contact voids closed in the width direction of the plate are provided at the butted end surfaces of the two bar members. Then, an alternating magnetic field is caused to flow through the loop-shaped gap in the thickness direction. It is assumed that the alternating magnetic fields flowing in adjacent gaps are 180 degrees out of phase with each other. After applying an alternating magnetic field for a predetermined time (3 to 5 seconds), the butted end faces of the two bar members are pressed and joined.

[0008] The loop-shaped gap portion provided at the butted end face of the bar material is formed by inserting a gauge of a predetermined shape between both end faces and pressing and butting the two bar materials with the gauge interposed therebetween.

[0009]

The butting operation of the two bar members is performed in such a state that the two bar members are each narrowly supported by the clamp device, and at least one of the clamp devices is narrowly supported by the bar material.
The other bar is moved forward by translational movement toward the clamp device that supports the narrow pressure, and the end faces of the two bars are abutted. At this time, since the translational movement of the clamp device allows the rotational movement, if the end surface of the bar material is in a one-side contact state, a moment force is generated by the translational force of the clamp device,
As a result, the clamp device rotates and the end face on the other side also starts to contact, and a good contact state is obtained over the entire surface.

In performing the butting operation of the end surfaces of the two bar members, a gauge for forming a required loop-shaped gap is inserted between the end surfaces of the two bar members. , A corresponding recess is formed in the butted end surface of the bar material. Therefore, if the gauge is released from the butt end surface, a loop-shaped non-contact gap is generated at the butt end surface at the boundary between the two bar members. In the present invention, two or more gaps are formed discontinuously in the width direction of the butted end faces.

Then, an alternating magnetic field is applied in the thickness direction in the loop-shaped gap. At this time, the application of the alternating magnetic field to the adjacent gaps is 180 degrees out of phase with each other. For example, when there are two gaps, the butting boundary surface between the two bar members becomes three places, Of course,
The induced current also flows through the central boundary surface, and the butted end surface is heated and heated. When this interface is heated to approximately 1350 ° C. or more in joining steel materials, the oxide scale (F
Since eO) melts and flows out, the two contact surfaces can be joined.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows an arrangement of components of a main part of a continuous hot rolling facility provided with a joining device according to an embodiment of the present invention. In this continuous hot rolling equipment, when a typical steel material is processed, a thickness of about 1000 to 1100 ° C manufactured by rough rolling or a thin slab continuous casting machine, a thickness of about 30 to 50 mm, a sheet width of 700 to 2000 mm, and a sheet length of 60 are used. Bar materials of up to 80 m are sequentially joined, and a continuous rolling operation is performed by the finishing mill 11.

That is, the rear end 90 of the preceding bar member 8 is cut by rotating the two drums 2 provided with the blades 3 in the shearing machine 1 in the direction of the arrow shown in the figure. And the rear end 9 of this bar material 8
Numeral 0 is narrowly supported by the clamp device 14 in the joining machine 4.
During this time, the rolling of the bar material by the finishing mill 11 is advanced. At this time, the supply of the bar material 8 to the finishing mill 11 is performed by adjusting the speed of the input / output pinch rollers 6 and 7, and This is done by releasing. The difference between the rolling speed and the loop feed speed is compensated by pulling and rotating the wheels 12 of the welding machine 4 with the cylinder 5 and moving the welding machine 4. In such a state, the leading end 91 of the following bar material
Is also cut by the above-mentioned shearing machine 1, transferred into the joining machine 4, and supported by the clamping device 15 under a narrow pressure.

The butting of the two bars 8, 9 and the synchronized movement of the joining machine 4 with the bars 8 are performed as shown in FIG. That is, the arrival state of the bar material on the entry side of the welding machine 4 is detected by the camera 92 on the entry side, and the butting state of the bar material in the welding machine 4 is detected by the camera 93 arranged in the middle. Based on this detection signal, the controller 80 supplies a clamp signal for the two bar members to the clamp cylinder 16 to support the bar members 8 and 9 in the joining machine 4 under a narrow pressure. Further, in order to compensate for the difference between the rolling and the loop speed described above, the amount of oil from the hydraulic source 94 is controlled by a valve 81 by a signal from the controller 80 to operate the hydraulic cylinder 5, and the bar members 8, 9 and the joining machine are connected. 4 is synchronized.

FIG. 7 shows a cross section taken along line BB of FIG. In this figure, the clamp device 14 has a clamp frame 14a fixed to the joining carriage 13 with bolts 26, and the preceding bar 8 is supported in the clamp frame 14a. That is, the bar member 8 is narrowly supported by the upper pressing plate 33a which is raised and lowered by the piston 32 of the cylinder 16 and the lower pressing plate 33b which is raised and lowered by the cylinder 36.

The following bar member 9 is supported as shown in FIG. 8 showing a cross section taken along the line CC of FIG. That is, the clamping device 15
Has a clamp frame 15a, and the following bar 9 is narrowly supported by the upper and lower pressing plates 35a and 35b in the clamp frame 15a as in the case of FIG. However, this clamp frame 15a is not fixed to the joining cart 13 but is loaded via the seat 41 so as to be slidable on the upper surface 34 of the cart. The seat 41 is guided by the guide 28. The outer edge of the seat 41 has an arcuate curved surface 97.
Are formed.

FIG. 3 shows a cross section taken along the line AA in FIG.
In this figure, a clamp frame 14 a for narrowly supporting the bar member 8 is fixedly attached to the joining carriage 13 with bolts 36. On the other hand, the clamp frame 15 a for narrowly supporting the bar member 9 is loaded on the carriage 13 via the seat 41. Then, the clamp frame 15a pushes and pulls the frame 95 provided on the clamp frame 15a by the two right and left cylinders 21 attached to the overhang frame 29 of the carriage 13, and abuts the end faces 27 of the two bar members 8,9. . In this butting operation, two bar materials are used as the holding plates 33a and 33.
b and 35a, 35b.

The end surfaces of the two bar members 8 and 9 are butted by pressing the clamp frame 15a for narrowly supporting the bar member 9 toward the preceding bar member 8 by two cylinders 21. At this time, even if one plate width end of the end surfaces of the two bar members 8 and 9 first hits, the outer edge of the seat 41 is an arc-shaped curved surface 97, so the clamp frame 15a is connected to the guide 28. The frame 15a rotates on the side where the end surfaces of the bar members 8, 9 are not in contact, and the end surfaces of the bar members 8, 9 over the entire width are abutted.

In the above description, one clamp device 14 shown in FIG. 2 is fixed, but it is also possible to allow at least this to perform a translational movement in the longitudinal direction of the bar material. In this case, the preceding bar material 8 is
When there is an error with respect to a predetermined joining position after the pressure is supported by the narrow pressure, it is possible to adjust the position by moving the clamp device 14 forward and backward.

In FIG. 3, two loop-shaped gaps 60a and 60b are provided at the butted end surfaces of the two bar members 8 and 9. An alternating magnetic field is applied to this portion as shown in FIG. FIG. 6 is a diagram showing a central section taken along line DD in FIG. In the figure, two gaps 60a,
The magnetic poles 17a and 17b are connected to the cylinder 45 from the left and right in the 60b portion.
To move and set. The coils 46a and 46b are set up and down on one magnetic pole 17a, and the coils 18a and 18b are set up and down on the other magnetic pole 17b. An alternating current is applied to these coils by an inverter 46. Since currents having phases different by 180 degrees flow through the coils of the two magnetic poles 17a and 17b, the directions of the magnetic fields 97 and 98 generated in the magnetic poles 17a and 17b are opposite to each other. For this reason, as shown in FIG. 9, induced currents ia and ib flow in opposite directions around the loop-shaped gaps 60a and 60b at the butted end surfaces of the two bar members 8 and 9. In this way, the current flowing through the central boundary surface 27b becomes the same direction by the two currents ia and ib, and the three boundary surfaces 27a,
All parts 27b and 27c are heated and heated.

Next, a method of forming a gap at the end face where the two bar members meet will be described with reference to FIG. 4 showing a cross section taken along line EE in FIG. In this figure, before the two bar members 8 and 9 abut each other, the arm 5 is moved up and down by moving the cylinder 53 up and down.
4 sets a gauge 50 suspended between the fork 51 and the end 52 between the two bar members 8 and 9. A hole 89 is formed in the center of the gauge 50, and the edge 88 is formed stepwise. FIG. 5 shows a state in which the gauge 50 is interposed between the two bar members. That is, the position of the step edge portion 88 of the gauge shown in FIG. 4 is determined according to the width of the bar material.
Then, as shown in FIG. 5, the real part of the gauge 50 forms loop-shaped gaps 60a, 60b intermittently formed at the butted end faces of the two bar members 8, 9.

In FIG. 5, the two bar members 8 and 9 are clamped by respective pressing plates 33a and 33b and 35a and 35b. In this example, the lower pressing plates 33a and 33b
33b is moved in the direction of the arrow to form a recess in the real part of the gauge 50. Therefore, by releasing the gauge 50 from the state of FIG. 5 and abutting the bar members 8 and 9 again, FIG.
As shown in (2), two loop-shaped gaps 60a and 60b are formed.

FIG. 10 shows another example of the shape of the gauge. The gauge 62 shown in FIG. 10 does not have a hole at the center, and the gauge 62 is connected to two bar members 8, 9 as shown in FIG.
When the gauge is inserted into the gap and presses the boundary surface, the gauge 62 is pulled out and butted again, and one loop-shaped void 64 is formed as shown in FIG. When one magnetic pole 63 is set in the gap 64 as shown in FIG. 12 and an alternating current is applied to the coils 64a and 64b, a magnetic field is generated in the vertical direction. Therefore, an induced current flows as shown in FIG.
The boundary surfaces 87a and 87b on the plate width end side are heated and joined. By the way, since the joining by the above-mentioned method is performed only at the end portion of the sheet width, it is difficult to perform the rolling in the next step by applying a sufficient tension.

An embodiment which solves the above disadvantages will be described with reference to FIGS. The gauge 70 in FIG. 14 has a shape that can be set in the state shown in the figure with respect to the cross section of the bar member 9 indicated by the two-dot chain line. That is, the center of the sheet width is a solid gauge for the entire sheet thickness, and the other portions are shaped and arranged such that only a part of the sheet thickness has a solid gauge. FIG.
Shows a state in which such a gauge 70 is inserted between the two bar members 8 and 9 to perform a pressing operation. This gauge 70
Is removed, the two bar members 8 and 9 are again butted to obtain a state as shown in FIG.

That is, although a loop-shaped gap 72 is provided at the center, the other part of the butted end face is a U-shaped groove with a part of the plate thickness recessed, and the joining area is reduced. . This is advantageous in that the joining section in the plate width direction increases.

In the present invention, the frequency of the induction heating current is 100 to 1000 Hz, and the current to be used varies depending on the plate material to be handled.

[0027]

(1) In joining the two preceding and succeeding bar materials before the hot strip finish rolling is performed,
The joining surfaces of the two bar members are abutted against each other by narrowing pressure support of the two bar members with the respective clamp devices, and at least one of the clamp devices is moved forward by the translational motion while allowing the other clamp device to rotate. As a result, uniform butting over the entire bar material is possible.

(2) At the butted end face of the two bar materials,
By providing two or more intermittent loop-shaped gaps, and applying alternating magnetic fields having a phase difference of 180 degrees in the thickness direction to each of the adjacent gaps, circulation is performed in opposite directions in the loop-shaped adjacent gaps. Since the induced current is induced, it is possible to join not only at both ends in the width direction, but also at the center at the butted end faces in the plate width direction, and it is possible to increase the joining strength, and to stabilize the joining bar material. Continuous rolling becomes possible.

(3) A loop-shaped gap at the butted end face of the two bar materials, which is required in the induction heating type joining method of the bar materials, is obtained by inserting a gauge between the two bar materials and
The two bars can be easily formed by butting using the pressing force of the butting means of the two bars, then removing this gauge and butting the two bars again. Various loop-shaped voids can be formed by changing the shape of the gauge.

(4) As described in the above item (1), the butting of both end surfaces of the bar material to be joined can be performed extremely accurately over the entire width of the plate. The present invention can be applied not only to the joining by the induction heating method but also to any joining method such as an arc welding method, a high-frequency induction heating method, and a gas burner cutting welding method.

[Brief description of the drawings]

FIG. 1 is a view showing a continuous hot rolling equipment provided with a bar joining apparatus according to one embodiment of the present invention.

FIG. 2 is a front view of the bar joining apparatus shown in FIG.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is a view showing a state of forming a loop gap in a bonding surface by inserting a gauge of the bar bonding apparatus, as viewed in a section EE of FIG. 2;

FIG. 5 is a plan view showing a state where a loop gap is formed in a joint surface by inserting the gauge of FIG. 4 from above.

FIG. 6 is a sectional view taken along line DD of FIG. 2;

FIG. 7 is a sectional view taken along line BB of FIG. 2;

FIG. 8 is a sectional view taken along line CC of FIG. 2;

FIG. 9 is a diagram showing a state of generation of an induced current in a two-loop gap.

FIG. 10 is a front view of a gauge forming a one loop gap.

FIG. 11 is a diagram showing a state of forming one loop gap.

FIG. 12 is a diagram showing a magnetic pole for one loop gap.

FIG. 13 is a diagram showing a state of generation of an induced current in one loop gap.

FIG. 14 is a front view of a gauge forming a U-grooved one-loop gap.

FIG. 15 is a diagram showing a use situation of the gauge shown in FIG. 14;

FIG. 16 is a diagram showing the shape of a U-grooved one-loop gap and the state of generation of induced current.

[Explanation of symbols]

 Reference Signs List 4 joining machine 8, 9 bar material 13 traveling carriage 14, 15 clamping device 17 magnetic pole 21 cylinder 41 seat 50 gauge 60a, 60b loop-shaped gap 62 gauge 70 gauge 97 curved surface

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-4-89109 (JP, A) JP-A-4-89120 (JP, A) JP-A-63-49307 (JP, A) JP-A-51- 95950 (JP, A) JP-A-49-97739 (JP, A) JP-A-4-288913 (JP, A) JP-A-4-89115 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B21B 15/00 B21B 1/26 B23K 20/00 340 H05B 6/10 381 B23K 101: 16

Claims (10)

(57) [Claims] 1. A bar material joining method for joining a rear end surface of a preceding bar material and a front end surface of a succeeding bar material in order to continuously finish-roll the hot strip, wherein each of the two bar materials is clamped. Bar material joining characterized in that at least one of these clamping devices is advanced by a translational motion while allowing a rotational motion to abut the end surfaces of the two bar materials, and then the both end surfaces are joined. Method. 2. The method of joining bar materials according to claim 1, wherein
The joining machine equipped with the two clamp devices is configured to be able to travel, and when the preceding bar material rear end face approaches the joining position of the joining machine, the joining machine starts moving together with the bar material, and the preceding bar material rear end face is moved. When reaching the predetermined position of the welding machine, the preceding bar material is narrowly supported by the preceding bar material clamping device, and the preceding material and the welding machine are moved in synchronization with each other, and then the succeeding bar material reaching the welding position is trailing. Narrow pressure support by the bar material clamp device, the forward bar material clamp device is advanced by translational motion while allowing the rotary motion, but the leading end surface of the following bar material abuts the rear end surface of the preceding bar material, A bar material joining method comprising joining both end surfaces. 3. A bar joining apparatus for joining a rear end face of a preceding bar material and a wire end face of a succeeding bar material in order to continuously finish-roll the hot strip, wherein each of the two bar materials is subjected to a narrow pressure. Two clamping devices to be supported, and moving butting means for advancing at least one of the two clamping devices by a translational motion while allowing a rotational motion to abut the end faces of the two bar members;
And a joining means for joining the butted end faces. 4. A bar joining apparatus according to claim 3, wherein
A traveling unit having the two clamping devices, the moving butting unit and the joining unit mounted thereon, wherein the moving butting unit moves the following bar material clamping device forward by a translational motion while allowing a rotational motion, and A means for abutting a front end surface of the bar member on a rear end surface of the preceding bar member. 5. A bar joining apparatus according to claim 4, wherein
A joining machine including the two clamping devices, the moving butting means, the joining means, and the traveling means; and control means for the joining machine, wherein the control means is arranged such that a preceding bar material rear end face is located at a joining position of the joining machine. When approached, the movement of the joining machine by the traveling means starts, and when the preceding bar material rear end surface reaches a predetermined position of the joining machine, the preceding bar material is narrowly supported by the preceding bar material clamping device, and The joining machine is moved synchronously, and then the following bar material reaching the joining position is narrowly supported by the following bar material clamping device, and the following bar material clamping device is moved forward by translation while allowing the rotary motion. A bar joining apparatus characterized in that the leading end face of the following bar is brought into contact with the trailing end of the preceding bar, and then a joining machine is operated to join both end faces. 6. A bar joining apparatus for joining and joining a rear end surface of a preceding bar member and a front end surface of a succeeding bar member in order to continuously finish-roll the hot strip, wherein the two bar members are joined. A gauge means for forming at least two or more separate loop-shaped voids in the width direction of the end face;
Alternating magnetic fields having different degrees of phase are applied in the width direction of the bar material, and the induced current induced thereby is caused to flow in the opposite direction in the loop-shaped gap adjacent to the loop-shaped gap in a loop-like manner.
Heating means for raising the temperature of the butted end surface of both bar materials adjacent to the loop-shaped gap by the induced current, and butting means for pressing the butted end surfaces of both bar materials and joining both end surfaces simultaneously with the temperature increase A bar joining apparatus characterized by the above-mentioned. 7. A bar material joining method for abutting and joining a rear end surface of a preceding bar material and a front end surface of a succeeding bar material in order to continuously finish-roll the hot strip, wherein the end surfaces of the two bar materials are joined. Before butting the two bar materials, a gauge having a predetermined shape is inserted between the end surfaces of the two bar materials, and then the two bar materials are pressed and joined in a state where the gauges are inserted. At least one loop gap is formed at a location corresponding to the gauge, then the pressing force is released, the gauge is extracted, and the end faces of the two bars are abutted again. Then, an induced current is generated around the loop gap. A bar that is heated to heat the butted end face portion adjacent to the loop-shaped gap, and simultaneously presses the butted end faces of both bar materials to join both end faces. Material joining method. 8. The bar material bonding method according to claim 7 , wherein
When forming a loop-shaped gap in the butted end surfaces of the two bar materials, a groove having a U-shaped cross section is formed in the width direction of the butted end surfaces using the same gauge. 9. A bar joining apparatus for joining and joining a rear end surface of a preceding bar member and a front end surface of a following bar member in order to continuously finish-roll the hot strip, wherein the two bar members are joined. Abutting means for abutting and pressing the end faces, and the two bars inserted between the end faces of the two bar members and pressed by the abutting means.
A gauge means for forming at least one or more loop-shaped gaps at the butted end surfaces of the two bar materials, and an induced current flowing around the loop-shaped gap while the two bar materials are pressed against each other by the butting means. Heating means for raising the temperature of the butted end face portion adjacent to the loop shape. 10. A bar material joining apparatus according to claim 9 , wherein said gauge means forms said loop-shaped gap at the abutting end surface of said two bar materials and has a U-shaped cross section in the width direction of said abutting end surface. A bar material joining device having a shape for forming a groove.