JPH04190916A - Device and method for heating apron and end part of sheet bar on hot rolling line - Google Patents

Abstract

PURPOSE:To prevent the temperature of both sides of sheet bar from reducing and to prevent the downward warping by making an apron arranged with a sheet bar end edge part heating device movable to the sheet bar lateral direction between rollers of a table roller. CONSTITUTION:Because an apron 8 is movable to the lateral direction of a sheet bar 3, so the induction heating coils 6A, 6B can be set at the both sides of right and left of this apron 8. Accordingly, the induction heating coils 6A, 6B are co-existed with the apron 8 and made to co-operate freely between rollers of the table roller 5, 5, the end part of the sheet bar 3 can be heated, also the downward warped sheet bar 3 can be prevented from creeping under the roll 5 with the exsistence of the apron 8. Further, beccause the apron is made movable in the width of the sheet bar, the sheet bar 3 is always guided on the table roller 3.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides an apron for a hot rolling line for preventing abnormal sheet passing in a hot sheet bar and compensating for a temperature drop at the end of the sheet bar. The present invention relates to a sheet bar end heating device and its heating method.

[Conventional technology]

In a continuous hot rolling line, the stored heat of the rolled material during the processing process is gradually lost due to the atmosphere, the rolls and their cooling water, descaling by high-pressure water, etc. Even in heat removal, the amount of heat removed from the widthwise ends is larger than that from the center, and as a result, the widthwise ends become lower in temperature, leading to material defects.

Therefore, to solve this problem, for example, "Tetsu-to-Hagane JVO1
, 72; 1986 No. 2 P 177-178 is already in common use.

However, the edges of the material to be rolled become cold only in the width direction, and the amount of heat removed near the tip in the longitudinal direction is large because it is bitten by the cooling rolls during rolling.
On the other hand, in the central part in the longitudinal direction, the roll is heated by heat input due to contact from the rolled material and heat input due to processing heat, so the amount of heat removed is quite small compared to the tip part.

In addition, heat is removed from the end face of the tip near the tip of the rolled material due to descaling with high-pressure water, etc., so the total amount of heat is removed from the front and back surfaces of the tip, both widthwise end faces, and the above-mentioned end faces. Since heat is removed from the 5 sides, it is natural that the center part in the longitudinal direction (7 has a larger amount of heat removal than the 4 sides). This will result in material defects due to oxidation.This material defect will naturally result in a rejected product, so the first way to solve the problem is to use a finishing mill group as shown in Figure 7. The easiest method is to cut it off with the crop 7 noya 4 placed in front of 2, and the second method is as proposed by the present applicant in Japanese Patent Application Laid-Open No. 1-32100.
No. 9, as shown in Japanese Unexamined Patent Publication No. 2-6002,
A pair of end heating devices disposed opposite to each other in the width direction of the seat bar are moved in the width direction of the seat bar to compensate for the temperature drop at the tip end.

[Invention or problem to be solved]

However, in the first method described above, there is a problem that the thickness of the truncation is too large to be cut off as a material defect, and the product yield is reduced.In addition, the temperature drop when finishing rolling is performed after the tip is truncated. It was not a sufficient countermeasure because it did not contribute in any way to the problem.

In addition, the second method mentioned above solves all of the problems in the first method, or there are problems as described below, and I will explain this point by attaching a diagram from the same bulletin in Figure 5. .

This figure is a view of the sorter 3 viewed from the direction of movement, and the thickness and width of the sheet bar 3 are shown. Same figure (B)
When the induction heating coil (hereinafter abbreviated as inductor) GA on the operation side is conveyed to the seat bar 3 or directly below it, it moves in the direction of the arrow toward the drive side and heats the note bar 3 among other things. .

At this time, the operation side inductor 6A moves to the center in the width direction of the seat bar. Thereafter, as shown in FIG. 2(c), the driving side inductor 6B heats the seat bar 3 while moving toward the operation side H in the opposite direction as described above, and moves to the center in the width direction. At this time, the operating side inductor 6A moves toward the operating side while being heated in the same way to avoid collision. Finally, as shown in FIG. 3D, the drive side inductor 6B is heated while moving toward the drive side, and returns to the widthwise end heating position of the seat bar 3.

The above is the specific content of the prior art, and the equipment for realizing this is shown in FIG. , Ishidaku 6A,
A space is required for the seat bar 6B to move from the end in the width direction of the seat bar to the center. Therefore, the apron 7, which is located between the common table rollers 5, cannot be placed at the location where an end heating device such as an inductor is installed.

On the other hand, the phenomenon of upward or downward warping in L-Dopa is caused by various factors, such as the rolling reduction rate during rough rolling, the difference in roll surface roughness of the F lower rolling roll, and the temperature difference between the front and back surfaces of N-1 Hepar. Kaari,
It is unavoidable that some percentage of this will occur due to fluctuations in operation. If the downward curvature is large, in the worst case scenario, it is expected that the table roller will slip under the table roller, so to prevent this from happening, the apron 7 mentioned above is generally installed between the rollers.

By the way, the prior art has a major problem in that since no apron is installed, it is impossible to completely eliminate the possibility of an accident due to the above-mentioned bowing.

This invention was made in view of the above-mentioned conventional problems, and by configuring an apron to be movable in the width direction of the steering bar, and arranging inductors on both left and right sides of the apron, The purpose is to solve the above issues.

[Means to solve the problem]

In order to achieve the above-mentioned object, the present invention has been developed to provide the following advantages:
In the apron provided between the rollers of the table rollers, which is provided with a sheet bar edge heating device that is movable in the sheet bar width direction and has a heating function for the longitudinal ends of the sheet bar, It is preferable that the sheet bar end heating device be used as the apron of a movable hot rolling line, and that induction heating coils are disposed on both sides of the nib one in the line direction. Furthermore, when the heating device heats the tip of the sheet bar, the movable apron between the table rollers is moved in the width direction of the sheet bar in accordance with the movement of the sheet bar end heating devices disposed on the left and right sides of the apron in the line direction. fart,
It is desirable to adopt a method of heating the tip of the seat bar by moving it within the width of the seat bar.

[Effect]

Since the present invention is constructed as described above, the apron is movable in the width direction of the seat bar, so inductors can be provided on both the left and right sides of the apron. In other words, the inductor, which could freely move in the width direction of the sheet bar between rollers without an apron as in the past, can now coexist and cooperate with the apron, and the end of the sheet bar can be heated as in the past. ,
The presence of the apron can prevent the downwardly curved sheet bar from slipping under the roll. Furthermore, since this movable apron is adapted to be moved within the width of the seat bar, the seat bar can always be guided onto the table roller.

〔Example〕

The present invention will be explained below with reference to the drawings. 1 to 4 are diagrams for explaining one embodiment of the present invention.

1 to 3 are general views of a movably constructed apron according to the present invention, in which FIG. 1 is a side view in the line direction, FIG. 2 is a view in the direction of arrow A in FIG. 1, and FIG. It is a view taken along arrow B in FIG. 1, and FIG. 4 is a diagram explaining the heating method according to the present invention.

In the figure, the apron 8 has both lower ends connected to the trolley 13.1.
It is supported and fixed by 3. The cart 13 has wheels 9 attached to it via a support stand 13a for fixing the apron 8 and bearing boxes 12 provided at both ends of the lower part of the support stand, so that it can move on rails 14.

However, this rail 14 is laid so that the apron 8 can move between the table rollers 5.5 of the rolling line in its longitudinal direction, that is, in the width direction of the sheet bar.

Note that the moving distance of the trolley 13 depends on the width of the seat bar.
A separate means (not shown) is provided to keep the width within that width.

Next, the sheet bar end heating device and the heating method using the same will be explained sequentially over time with reference to FIG. 4 as shown in (A) to CG'). In addition, illustration of the table roller 5 is omitted in the drawings from FIG. B onwards.

The seat bar end heating device is configured such that a pair of induction heating coils (inductors) 6, which are provided close to the seat bar 3 and facing each other, are movable.

Now, when the sheet bar 3 is conveyed and approaches the end heating device 6 (A), the operating side inductor 6A moves toward the center Y in the width direction of the sheet bar, and waits for the sheet bar 3 at the center Y. At this time, since the apron 8 is supported by the wheels 9, it is pushed by the operation side inductor 6A and moves to the drive side. This position when moved is the position shown in (B), or the apron 8 is within the width of the seat bar 3, so that the apron's original function is performed, that is, it prevents the accident of the downwardly warped seat bar from crawling under the roller 5. It does not cause any problem when turned on.

Next, when the seat bar 3 is conveyed to a predetermined heating position (C), the seat bar 3 is brought into a state where it can be considered stopped.

And the operating side inductor 6A and the driving side inductor 6B
While heating the end portion of the seat bar 3, move it toward the operation side (lower side in the figure) (D). The moved operating side inductor 6A is at the end position in the width direction (the seat bar 3
(E) to prepare for heating the widthwise edges of the seat bar 3 (E).

On the other hand, the drive-side inductor 6B moves while heating the width direction center Y (D), or pushes the apron 8 in the same direction when moving. Then, after heating in the width direction,
Move in the opposite direction to 6A in the same way as 6A (E).

When both the operating side and driving side inductors 6A, 6B return to their predetermined positions (F), the sheet bar 3 is in a conveying state, and both edges in the width direction thereof are heated (G).

Here, since the apron 8 is within the width of the seat bar 3 at any timing between (A) and (G) above,
The above-mentioned accidents caused by the downward warping of the seat bar 3 can be prevented. That is, according to the present invention, it is possible to heat the longitudinal end portion of the seat bar without worrying about accidents caused by a downwardly warped seat bar, so that it is possible to completely compensate for heat loss from five sides of the seat bar.

In this example, the case is shown in which the apron is pushed by the inductor and driven, but the inductor may be controlled and moved in synchronization with the apron.

Further, in the above embodiments, an example is shown in which the inductor is moved between the same rollers, but an inductor may be provided between each roller on either the drive side or the operation side.

〔Effect of the invention〕

FIG. 8 shows the effect of heating the tip end in the longitudinal direction of the sheet bar according to the present invention. This is shown as the difference between In other words, it is shown that if there is no heat increase, the temperature at the tip of the seat bar will drop significantly, causing a material problem, or if there is a heat increase, there will be no problem.

The present invention may directly bring about this effect, and when used as a device that heats the tip of the seat bar, it can have the effect of preventing accidents caused by the stochastic downward curvature of the seat bar.

[Brief explanation of the drawing]

FIG. 1 is a side view of an apron according to the present invention in the line direction, FIG. 2 is a view taken in the direction of arrow A in FIG. 1, and FIG.
4 shows the sheet bar heating method according to the present invention in the chronological order (A), (B), (C), (D).
, (E'), (, F'), and Figure 5 shows the conventional heating method in chronological order (A), (B), (C).
, (D), and FIG. 6 shows equipment for carrying out the conventional heating method, where (A) is a side view in the line direction, and (B) is a side view of the same (A). Plan view, No. 7
The figure is a conceptual diagram of a general sheet bar rolling line, and FIG. 8 is a graph showing the effect of heating the tip of the sheet bar in the longitudinal direction according to the present invention in comparison with a conventional example in which the tip is not heated. 2... Finishing rolling machine, 3... Sheet bar, 5... Table roller, 6A, 6B...
...Induction heating coil (inductor), 7... Apron, 8... Movable apron.

Claims (3)

[Claims] (1) A sheet bar edge heating device installed on both sides of the sheet bar in the width direction of the continuous hot rolling line, which is movable in the width direction of the sheet bar and has a function of heating the longitudinal ends of the sheet bar. 1. An apron for a hot rolling line, characterized in that the apron is provided between rollers of a table roller on which a sheet bar is disposed, and is configured to be movable in the width direction of a sheet bar. (2) A sheet bar end heating device in a continuous hot rolling line, characterized in that induction heating coils are disposed on both left and right sides in the line direction of an apron configured to be movable in the width direction of the sheet bar. (3) To heat the tip of the seat bar, move the movable apron between the table rollers in the width direction of the seat bar in accordance with the movement of the seat bar end heating devices disposed on both the left and right sides of the apron in the line direction; A method for heating a tip of a seat bar, characterized in that the tip of the seat bar is moved within the width of the seat bar.