JP3258787B2 - Transfer route switching method and apparatus for hot-dip coated steel sheet and cold-rolled steel sheet - 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 switching a steel sheet transport route of a combined production facility capable of producing a hot-dip coated steel sheet and a cold-rolled steel sheet by the same equipment.

[0002]

2. Description of the Related Art Conventionally, in a plating apparatus section disposed on a line of a hot-dip galvanizing equipment, a sink roll 3 and support rolls 8a, 8b in a plating bath 2a in a plating tank 2, as shown in FIG. In-bath equipment such as the above is disposed, and the steel sheet 1 for hot-dip plating entering from the heat treatment furnace 5 which is a pretreatment facility is led into the plating bath 2a in the plating tank 2 via a snout 6 for isolating from the oxidizing atmosphere. It has become.

[0003] While the steel sheet 1 immersed in the plating bath 2a is hot-dip galvanized, the traveling direction of the steel sheet 1 is changed upward through a sink roll 3, and a pair of support rolls in the bath arranged opposite to each other. It is supported by 8a and 8b and pulled up vertically, pulled out from the plating bath 2a, and wiped off excess molten zinc by a gas jet injected from a pair of gas wiping nozzles 4a and 4b to obtain a predetermined zinc adhesion amount. Further, a top roll 9 for changing the plated steel sheet 1 in a horizontal direction is provided considerably above the plating tank 2.

In order to use a hot-dip galvanized steel sheet production line requiring such a plating treatment as a cold rolled steel sheet production facility, the steel sheet conveyance path is switched so that the steel sheet does not enter the plating bath of the plating tank. There must be. Until now, in order to switch the transport route of the steel sheet, the steel sheet is cut near the plating unit and the steel sheet is transported without being immersed in the plating bath using the transport roll installed above or near the plating tank. That is, so-called pass replacement is performed.

[0005] As described above, it is necessary to cut the steel plate, change the transfer route to the transfer rolls, connect the steel plate, and the like for the path change. Therefore, there is a problem that not only productivity is lowered but also maintenance work is increased. In order to solve such a problem, JP-A-2-34762 discloses that a hot rolled steel sheet is manufactured using a sink roll immersed in a plating bath in a plating tank, while a cold rolled steel sheet is manufactured using the sink roll. Using a sink roll as a deflector roll at a raised position has been proposed.

[0006] However, it is extremely difficult to use the sink roll as it is as a deflector roll simply by dipping it in a plating bath and pulling up the used sink roll during the production of a cold-rolled steel sheet. For example, plating metal is wrapped around and adhered to the body of the sink roll where the cold rolled steel sheet contacts,
Unless this is completely removed, there is a problem that flaws are generated in the cold-rolled steel sheet. Furthermore, in the sink roll bearing, the plating metal has entered the bearing,
When the sink roll is pulled upward from the plating bath, there is a problem that the plated metal solidifies and cannot be used as a bearing.

On the other hand, in the continuous galvanizing line, since the plating operation is continuous by combining steel sheets of various sizes, it is necessary to adjust the plating processing conditions to the plating conditions of each plated steel sheet. Therefore, various plating steel sheets are plated in a predetermined processing order so that plating conditions (for example, pretreatment conditions, plating bath conditions, steel sheet running conditions, etc.) do not suddenly change. However, under the current situation where demand is diversifying, it is difficult to sufficiently satisfy plating treatment conditions only by such measures. Therefore, in reality, a continuous plating process is performed by appropriately inserting a dummy material (hereinafter, referred to as a passing plate material) for adjusting plating conditions. In addition, when a manufacturing facility is stopped and restarted for maintenance work or the like, a passing material is used to adjust plating conditions. Moreover, since these pass-through materials are plated in the same manner as the process materials to be shipped as products, it is impossible to reuse the pass-through materials that have been used once, resulting in an increase in cost.

[0008]

In order to be able to use a hot-dip coated steel sheet manufacturing facility as a cold-rolled steel sheet manufacturing facility, it is necessary to easily and quickly switch the strip conveyance path in the plating apparatus. However, as described above, simply pulling the sink roll used during the production of hot-dip coated steel sheets above the plating bath causes flaws on the strip due to the wrapping of the molten metal around the roll body and adhesion of the molten metal to the bearings. Non-rotation of the sink roll due to solidification or the like causes deterioration in quality, such as generation of scratches, and it is extremely difficult to use the sink roll as it is during cold rolled steel sheet production.

The present invention solves the above-mentioned problems, and makes it possible to switch from hot-dip coated steel sheet production equipment to cold-rolled steel sheet production equipment or from cold-rolled steel sheet production equipment to hot-dip coated steel sheet production equipment as quickly and easily as possible. It is an object of the present invention to provide a method and an apparatus for switching a steel sheet transport path of a manufacturing facility for both a hot-dip coated steel sheet and a cold-rolled steel sheet. In addition, when used as a hot-dip plating facility, when the dimensions of the strip to be treated change significantly, or when the production facility is stopped and restarted for maintenance work, the passing plate material that is necessary is not passed through the plating bath without immersion. It is an object of the present invention to provide a method and an apparatus for switching a steel sheet transport path, in which a sheet can be formed and a path can be changed to a plating path quickly and easily when processing conditions are satisfied.

[0010]

According to the present invention, there is provided a method for switching a steel sheet transport route of a combined production facility capable of producing a hot-dip coated steel sheet and a cold-rolled steel sheet by the same equipment. A plating tank is fixedly arranged, and a sink roll is arranged so as to be able to move up and down between a plating position and an upper evacuation position, and a deflector roll is retracted to the side of the line between the plating position and a lower evacuation position. When manufacturing a hot-dip coated steel sheet, the sink roll is lowered to the plating position using a lifting device, and immersed in the plating bath in the plating tank when manufacturing the hot-dip coated steel sheet between the position and the position in the line. While the deflector roll is retracted to the side of the line using the forward and backward moving device, the hot-dip coated steel sheet is wound around the sink roll and transported upward. When manufacturing cold-rolled steel sheets, the sink roll is raised from the plating position to the retreat position above the plating tank where the fixed roll is fixed, and the deflector roll is moved from the retreat position on the side of the line using the forward and backward moving device to a position within the line. A method of switching the transport path of a hot-dip coated steel sheet and a cold-rolled steel sheet, wherein the cold-rolled steel sheet is wound around a deflector roll and transported upward in a state where the steel sheet has been moved to a deflector roll.

[0011] According to a second aspect of the invention, the plating bath in the steel plate conveyance path switching apparatus of the alternate production facilities that can be produced by the same facilities dip plated steel sheet and cold rolled steel sheet, and arranged fixedly to the plating position And a sink roll arranged to be able to move up and down between the plating position and the upper evacuation position, a lifting device that supports the sink roll and moves up and down between the plating position and the upper evacuation position, and the plating position A deflector roll arranged horizontally movable between a retreat position on the line side and an in-line position between the upper sink roll retreat position and a deflector roll, and the deflector roll is moved to a retreat position on the line side and an in-line position. And a forward / backward moving device for moving forward and backward between the hot rolled steel sheet and the cold rolled steel sheet.

[0012]

[Action] When manufacturing a hot-dip coated steel sheet, the sink roll is lowered to the plating position, the sink roll is immersed in the plating bath, and the hot-dip coated steel sheet is wound around the sink roll, transported upward, and then cold rolled. When manufacturing steel sheets, raise the sink roll to the upper evacuation position, move the deflector roll from the side of the line to the in-line position between the plating tank at the plating position and the sink roll at the evacuation position, and cold roll. It switches so that a steel plate may be wound around a deflector roll and conveyed upward.

Therefore, unlike the conventional case where the sink roll is used as a deflector roll, it is possible to prevent the occurrence of defects such as the generation of flaws on the cold-rolled steel sheet due to the adhesion and solidification of the plated metal to the sink roll and the non-rotation of the sink roll. Not only that, the time for switching between the hot-dip coated steel sheet and the cold-rolled steel sheet can be reduced.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. In the hot-dip galvanized steel sheet manufacturing equipment of the present invention shown in FIG. 3, the plating tank 2 is arranged in accordance with the pass line of the steel sheet 1 sent from the continuous heat treatment furnace 5. A transport roll 7 for immersing the steel sheet 1 in the plating bath 2a is disposed on the entrance side of the plating tank 2 to change the running direction of the steel sheet 1 entering the plating bath 2a in the plating tank 2 and pull it upward. Are attached. Further, a top roll 9 for pulling up the plated steel sheet 1 from the plating bath 2a and changing its running direction to the horizontal direction is provided considerably above the plating tank 2.

In the manufacturing process of such a hot-dip coated steel sheet, a sink roll 3 is placed in a plating bath 2 a in a plating tank 2.
Wiping by immersing and disposing equipment in the bath to form a transport path for the steel sheet 1 to pass through the plating bath 2 and placing a plating solution attached to the steel sheet 1 drawn from the plating bath 2 directly above the plating bath 2 Controlling to a predetermined plating thickness by wiping with the nozzles 4a and 4b is the same as in the case of the conventional example shown in FIG.

In the present invention, as shown in FIGS. 1 and 2, the hot-dip plating bath 2 is fixedly disposed on a base 28, while a bath equipment such as a sink roll (hereinafter collectively referred to as a sink roll 3). Is raised and lowered by using the lifting device 10. A pair of screw jacks 23 provided in the elevating device 10 support the support frame 22 so as to be able to move up and down, and the screw jack 23 is engaged with a screw member 27. One screw member 27 is connected to the motor 26 and is connected to the other screw member 27 via the shaft coupling 25 and the intermediate shaft 24.

Therefore, when the motor 26 rotates forward or backward, the screw members 27 rotate in synchronism, whereby the pair of screw jacks 23 move up or down, so that the sink roll 3 supported by the support frame 22 is moved up and down. .
For this reason, as shown in FIGS. 1 and 3, the sink roll 3 is lowered and the plating position where the sink roll 3 is immersed in the plating bath 2a of the plating tank 2 and the upper part of the plating tank 2 fixed and arranged as shown in FIGS. It can be moved up and down between the retracted position.

As shown in FIGS. 1 and 2, between the plating position of the plating tank 3 and the upper sink roll retreat position, a deflector roll 11 moves back and forth between the retreat position on the side of the line and the position in the line. It is arranged so as to be able to advance and retreat using the moving device 12. The slide frame 13 of the forward and backward moving device 12 has a structure that horizontally moves on a slide base 15, and a screw shaft 17 is screwed into a nut member 16 attached to one end of the slide frame 13, The proximal end of the screw shaft 17 is rotatably supported by a bearing 15a, and is connected to a motor 18 via a shaft coupling 19.
When the motor 18 rotates forward or backward, the nut member 16 moves forward or backward integrally with the slide frame 13 only in the direction indicated by the arrow A as the screw shaft 17 rotates.

A bearing 14 mounted on the slide frame 13 supports a support shaft 11a of a deflector roll 11, and a base end of the support shaft 11a is connected to a motor via a shaft coupling 21.
The deflector roll 11 is rotated by rotating the motor 20. Next, the operation of the present embodiment will be described.

In the case of manufacturing a hot-dip coated steel sheet, the deflector roll 11 is retracted out of the line by using the forward and backward moving device 12, while the motor 26 of the elevating device 10 is rotated to rotate through the screw member 27. Screw jack
When the 23 is lowered, the support frame 22 supported by the screw jack 23 is lowered integrally with the sink roll 3, and the equipment in the bath such as the sink roll 3 is immersed in the plating bath 2 a in the plating tank 2. Then, as described above, the steel sheet 1 is
by molten zinc plating transported upward it is subjected wound around the sink roll 3 in a.

When switching from the hot-dip coated steel sheet manufacturing process to the cold-rolled steel sheet manufacturing process, as shown in FIGS. 2 and 4, the sink roll 3 is raised from the plating position to the upper evacuation position by using the elevating device 10. Let it. Next, the tension applied to the steel sheet 1 wound around the sink roll 3 is relaxed so that a slack of the steel sheet 1 is formed between the plating tank 2 and the sink roll 3 at the retracted position.

Next, the motor 18 of the forward and backward moving device 12 is rotated forward, for example, to rotate the screw shaft 17, whereby the slide frame 13 is advanced through the nut member 16. In this way, when the deflector roll 11 mounted on the slide frame 13 is moved forward from the retracted position on the side of the line to the position in the line, the steel sheet 1 in a state of slack between the sink roll 3 and the plating tank 2 is moved. The deflector roll 11 is inserted into the loop. Thereafter, a tension is applied to the steel sheet 1 and the steel sheet 1 is wound around a deflector roll 11 to switch to a conveyance path for manufacturing a cold-rolled steel sheet as shown in FIGS.

At the time of such switching, the in-bath support rolls 8a and 8b and the wiping nozzles 4a and 4b
It is preferable that each interval is kept open so as not to interfere with the steel plate 1. Further, since plating metal adheres to the in-bath equipment such as the sink roll 3 and the in-bath support rolls 8a and 8b, It is desirable to remove this. The switching from the cold-rolled steel sheet manufacturing process to the hot-dip coated steel sheet manufacturing process may be performed in the reverse operation of the switching from the hot-dip coated steel sheet manufacturing process to the cold-rolled steel sheet manufacturing process, and thus the detailed description is omitted.

[0024] Furthermore, the method is not immersed in the plating bath when using the passing plate material is widely used in hot-dip plating steel sheet production process provided by carrying out the switches Uh same to cold-rolled steel sheet production process from the hot dip plated steel sheet production process The good point is clear as described above, and the detailed description is omitted.

In this embodiment , a specific example in which the support of the deflector roll 11 is supported from only one side has been described. However, after the deflector roll 11 is inserted into the line, the deflector roll 11 is also supported on the non-insertion side. It is also possible to

[0026]

As described above, according to the present invention, the following effects can be obtained. The production of the cold-rolled steel sheet and the hot-dip coated steel sheet can be switched as quickly and easily as possible, so that the operation rate of the production equipment can be greatly improved. When the dimensions of the strip to be processed during the production of hot-dip coated steel sheets change significantly, or when the production equipment is stopped and put into operation after maintenance work, it is not necessary to immerse the passing material into the plating bath. It can be used and the production cost can be reduced. Uses a dedicated deflector roll without the use of a sink roll or other in-bath equipment used in the production of hot-dip coated steel sheets such as sink rolls during the production of cold-rolled steel sheets. High quality products can be stably and reliably manufactured.

[Brief description of the drawings]

FIG. 1 is a front view showing the arrangement of a plating tank and a deflector roll during production of a hot-dip coated steel sheet according to the present invention.

FIG. 2 is a front view showing the arrangement of a plating tank and deflector rolls during the production of a cold-rolled steel sheet according to the present invention.

FIG. 3 is a side view showing an arrangement of the apparatus at the time of manufacturing a hot-dip coated steel sheet according to the present invention.

FIG. 4 is a side view showing an arrangement of the apparatus at the time of manufacturing a cold-rolled steel sheet according to the present invention.

FIG. 5 is a side view showing an arrangement of the apparatus at the time of manufacturing a hot-dip plating of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steel plate 2 Plating bath 3 Sink roll 4 Gas wiping nozzle 5 Heat treatment furnace 6 Snout 7 Conveyance roll 8 Support roll in bath 9 Top roll 10 Lifting device 11 Deflector roll 12 Forward and backward moving device 13 Slide frame 14 Bearing 15 Slide base 16 Nut member 17 Screw shaft 18 Motor 19 Shaft joint 20 Motor 21 Shaft joint 22 Support frame 23 Screw jack 24 Intermediate shaft 25 Shaft joint 26 Motor 27 Screw member 28 Base

Claims (2)

(57) [Claims] In a method for switching a steel sheet transport route of a combined production facility capable of producing a hot-dip coated steel sheet and a cold-rolled steel sheet by the same equipment, a plating tank containing a plating bath is fixed and arranged, and a sink roll is plated. Between the plating position and the upper evacuation position, and the deflector roll is horizontally movable between the line side evacuation position and the in-line position between the plating position and the upper evacuation position. When manufacturing a hot-dip coated steel sheet, lower the sink roll to the plating position using an elevating device, immerse it in the plating bath in the plating tank, and use the forward and backward moving device to move the deflector roll to the line side. When the hot-dip coated steel sheet is wound around a sink roll and conveyed upward while the cold-rolled steel sheet is manufactured, Of the cold-rolled steel sheet from the plating position to the retracted position above the fixedly arranged plating tank and the deflector roll moved from the retracted position on the side of the line to the in-line position using the forward and backward moving device. A method for switching the transport path of a hot-dip coated steel sheet and a cold-rolled steel sheet, wherein the transport path is wound around a deflector roll and transported upward. 2. A hot dip plated steel sheet and steel sheet conveyance path switching device of the alternate production facilities for the cold-rolled steel sheet can be produced by the same facilities, a plating tank which is disposed fixed to the plating position, the plating position and the upper A sink roll disposed so as to be able to move up and down between the retracted position, a lifting device that supports the sink roll and moves up and down between the plating position and the upper retracted position, and the plating position and the upper sink roll retracted position. A deflector roll disposed horizontally to be able to reciprocate horizontally between a retreat position on the line side and an in-line position, and forward and backward moving the deflector roll between a retreat position on the line side and an in-line position A transfer route switching device for a hot-dip coated steel sheet and a cold-rolled steel sheet, comprising a moving device.