JPH07114994B2 - Coating steel plate baking equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is a method for baking a coated steel sheet, in which a coating film applied to the surface of a strip steel sheet is baked onto a strip steel sheet to continuously produce a strip-coated steel sheet. Regarding the device.

[Prior Art] FIG. 2 is a schematic view of an example of a conventional baking furnace for coated steel sheets.

FIG. 2 (A) is an example of a single-sided coated steel sheet, in which the strip-shaped steel sheet 1 traveling in the direction of arrow 11 has a coating film formed on the upper surface by the coating roll 3-1 and in the baking furnace 2 the coating film becomes a strip-shaped steel sheet. It is baked and processed in the cooling / drying device 6 to obtain a coated steel plate.
Since the coating film is not formed on the lower surface of the strip-shaped steel sheet 1 with the one-side coated steel sheet, the strip-shaped steel sheet in the baking furnace 2 is supported from below by the support roll 8
Even if it is supported by, the coating film will not be damaged. However, this furnace cannot manufacture double-sided coated steel sheets with one baking.

FIG. 2 (B) shows an example of a double-sided coated steel sheet. The strip-shaped steel sheet 1 has a coating roll 3-1 having a coating film formed on its upper surface and a coating roll 3-2 having a coating film formed on its lower surface. When the strip-shaped steel sheet 1 is supported by the support roll 8 in FIG. 2 (A) in the case of a double-sided coated steel sheet, the coating film on the lower surface has not been baked yet. Peel and damage. Therefore, in the case of a double-sided coated steel sheet, in order to keep the lower surface in non-contact until the baking is completed, the strip steel sheet 1
Causes the catenary 4-1 to be formed between the coating roll 3-2 on the lower surface and the exit-side roll 5 to run in the baking furnace 2. In the figure, 9 is a tension detecting end of the strip steel plate 1, 7 is a tension control unit, and 8 is a tension applying device for applying tension to the strip steel plate, for example, a bridle roll. In this device, the shape of the catenary 4-1 is the tension applying device 8
Is applied to the strip-shaped steel sheet 1 to control the strip-shaped steel sheet 1 between the coating roll 3-2 and the exit roll 5 by a tension that balances with the weight of the strip-shaped steel sheet 1. For example, while the strip steel plate having the same thickness and width travels in the baking furnace 2, the coating roll 3-2 and the delivery roll 5
Since the self-weight of the strip-shaped steel sheet 1 between and is always the same, tension is applied so that the tension of the strip-shaped steel sheet becomes constant by using the tension detecting end 9 and the tension control unit 7 that controls the tension of the strip-shaped steel sheet to be constant. Rotating the device 8 keeps the catenary 4-1 in the same shape. In a baking apparatus for coated steel sheets, strip-shaped steel sheets having different thicknesses and widths are welded to each other at the front end and the tail end in sequence and continuously run to manufacture various strip-shaped steel sheets having different thicknesses and widths. However, in the apparatus of FIG. 2 (B), the following problems occur when processing strip steel plates having different thicknesses and widths. In FIG. 2 (B), for example, 1-1 is a preceding thin strip steel plate, and 1-2 is a thick strip steel plate whose tip is welded to the tail end of 1-1. In this case, paint roll 3
-2 and the exit side roll 5 self-weight of the strip | belt-shaped steel plate increases one by one, while the welding joint part 10 moves to the exit side roll 5 from the coating roll 3-2. Therefore, until the tension control unit 7 is set to the strip steel plate 1-1, for example,
The catenary has a shape of 4-2, which causes a problem that the strip steel plate rubs the bottom of the baking furnace. Further, for example, when the tension control unit 7 is set in conformity with the strip steel plate 1-2, there arises a problem that the thin strip steel plate 1-1 is pulled and cut or deformed.

FIG. 2 (C) shows a catenary drying furnace described in Japanese Utility Model Publication No. 55-149194. In this catenary furnace, nozzle units 12-1, 12-2, 12-3, 12-4, which are divided in the longitudinal direction, are arranged so as to be bendable, and the nozzle units 12-1, 12-2, 12-3, 12-4 are arranged according to the shape 4 of the catenary of the strip steel plate 1. A furnace that bends bonds. However, this catenary furnace is a furnace on the assumption that the shape of the catenary of the strip steel sheet changes, and is not a furnace that reduces the change of the catenary shape.

[Problems to be Solved by the Invention] In the present invention, when the strip-shaped steel sheets having different thicknesses and widths are connected to each other at the leading end and the tail end and sequentially and continuously run, the shape of the catenary of the strip-shaped steel sheet is always a predetermined shape. A feature of the invention is to provide a baking device for coated steel sheets that can be controlled within a range.

[Means and Actions for Solving the Problems] FIG. 1 is an explanatory view of an example of a printing apparatus of the present invention. In the present invention, a shape detection sensor that detects the shape of the catenary is used. The shape detection sensor 13-1 does not detect when the catenary is below 4-3, but detects that when it reaches 4-3. Similarly, the shape detection sensor 13-2 does not detect when the catenary is above 4-4, but 4-4
When it reaches, the fact is detected. Therefore shape sensor
Using 13-1 and 13-2, the catenaries are 4-3 and 4
It is possible to detect whether or not the shape is between -4. The present invention also has a tension command unit 14. When the shape of the catenary moves upward and reaches 4-3, the shape detection sensor 13-
1 is the tension command unit that the catenary has reached 4-3
The tension command unit 14 commands the tension control unit 7 to reduce the tension of the strip steel sheet. This command causes the tension applying device, for example, the bridle roll 8, to slow down in rotation speed, and the catenary moves downward from 4-3. Therefore, the catenary is 4-3
It does not move upwards.

When the catenary reaches 4-4, the shape detection sensor
13-2 instructs the tension command unit 14 to that effect, but the command of the tension command unit 14 causes the bridle roll 8 to have a faster rotation speed, and the catenary moves upward from 4-4. Therefore, the catenary does not move below 4-4.

As described above, in the present invention, the tension command unit 14 sets the catenary based on the instructions of the shape detection sensors 13-1 and 13-2.
The tension of the strip steel plate is changed so that the shape is within the range of -3 and 4-4.

As the shape detection sensors 13-1 and 13-2, known non-contact detection sensors can be used.

FIG. 1 has a tension detecting end 9 and a tension control unit 7, and normally keeps the tension of the strip steel plate constant on the basis of these commands, and the catenary has an upper limit within a predetermined range 4-3 and 4-4. Although the example of operating to change the tension when reaching the lower limit or the lower limit has been described, the distance 15 from the detection sensor to 15 is accurately detected using a non-contact type detection sensor, for example, the strip steel plate. It is apparent that the same effect can be obtained by directly controlling the rotation speed of the tension applying device, for example, the bridle roll, so that the tension command unit 14 maintains the distance 15 at a certain value or less based on the above instruction. Therefore, it is natural that the tension detecting end 9 and / or the tension control unit 7 are not provided, or the shape detecting sensors 13-1 and 13-2 and the tension command unit 14 of the present invention also have these functions. Included in the present invention.

Further, FIG. 1 shows an example in which the rotating speed of the tension applying device (bridle roll) 8'on the input side is constant and the rotating speed of the tension applying device 8 on the output side is adjusted. In order to control the shape of the catenary of the strip steel plate 1, the rotational speed of the tension applying device 8 on the output side is kept constant, the command from the tension control unit 7 is transmitted to the tension applying device 8'on the input side, and 8 ' It can also be achieved by adjusting the rotation speed.

Further, although an example in which the delivery roll 5 is arranged in front of the cooling / drying device 6 has been described with reference to FIG.
Can also be arranged on the rear surface of the cooling / drying device 6.

EFFECTS OF THE INVENTION By using the baking apparatus for coated steel sheets of the present invention, the catenary can be controlled within a narrow shape range to manufacture strip-shaped coated steel sheets having different dimensions. Therefore, when the present invention is used, the strip steel plate does not rub the bottom of the baking furnace. Further, by using the present invention, the height of the baking oven shown by H in FIG. 1 can be reduced, and as a result, the coating film can be baked with high thermal efficiency.

[Brief description of drawings]

FIG. 1 is an explanatory view of an example of an apparatus for baking a coated steel sheet of the present invention, and FIG. 2 is a schematic view of an example of a conventional baking furnace for a coated steel sheet. 1 (1-1, 1-2): Strip steel plate, 2: Baking furnace, 3-1, 3-2:
Coating roll, 4 (4-1,4-2,4-3,4-4): Shape of catenary, 5: Delivery roll, 6: Cooling / drying device, 7: Tension control unit, 8 (8 '): Tensioning device,
9: tension detection end, 10: welded joint of strip steel plate, 11: running direction of strip steel plate, 12-1, 12-2, 12-3, 12-4: nozzle unit, 13-1, 13-2: Shape sensor, 14: Tension command unit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideo Otani 1 Kimitsu, Kimitsu-shi, Chiba Nippon Steel Co., Ltd. Kimitsu Steel Co., Ltd. (72) Inventor Osa Renji Kimitsu, Kimitsu-shi, Chiba Shin Nippon Steel Stock company Kimitsu Works (72) Inventor Hideaki Iwakura No. 1 Kimitsu, Kimitsu City, Chiba Shin Nippon Steel Co., Ltd. Kimitsu Works (56) References Japanese Patent Publication 53-14488 (JP, B2) Actual Public Sho 62 -14037 (JP, Y2)

Claims (1)

[Claims] 1. A coated steel sheet baking apparatus for forming a catenary, running and heating a coated steel sheet (1) to bake a coating film on the steel sheet (1). It has a shape detection sensor (13-1, 13-2) that detects the upper limit position and the lower limit position (4-3 to 4-4), and can be used as an instruction for both shape detection sensors (13-1, 13-2). A baking apparatus for coated steel sheet, comprising a tension command unit (14) for changing the tension of the strip steel sheet (1) so that the catenary falls within a predetermined shape range.