JP2011073036A - Winding device on hot rolling line, method of winding material to be rolled in hot rolling and method of manufacturing hot-rolled metallic strip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a winding device on a hot rolling line, a method of winding a material to be rolled in the hot rolling and a method of manufacturing a metallic strip by which the occurrence of loosening and the occurrence of telescoping are prevented even when the material is high-strength ultra-thick material. <P>SOLUTION: Guide rolls 5a, 5b for making a bending moment in the same direction as a bending moment by which the material 8 to be rolled is bent with a pair of pinch rolls 1a, 1b act are installed annexing to a pair of pinch rolls 1a, 1b. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a winding device in a hot rolling line, a method for winding a material to be rolled in hot rolling, and a method for manufacturing a hot rolled metal strip.

  As an example, the case of a hot strip rolling line 100 as shown in FIG. 4 is taken as an example.

  Hot rolling is generally a slab-like metal material produced by continuous casting, ingot-making, or ingoting, heated in a heating furnace to several hundred to several hundreds of degrees Celsius, and then placed on a hot rolling line. It is a series of processes of extracting and winding thinly and winding it into a coil shape by rotating the roll while pinching with a pair or a plurality of pairs of rolls.

  A metal material 8 having a thickness of 150 to 300 mm (hereinafter referred to as a material to be rolled) heated to several hundred to several hundreds of degrees Celsius by the heating furnace 10 is rolled to a thickness of 1.2 to 25 mm by a roughing mill 12 and a finishing mill 18. After being thinly extended into a metal plate (metal strip) shape and cooled by the cooling equipment 26, the coil is wound up by a coiler (winding device) 24.

  The table roll 7 conveys the material to be rolled 8 between the rolling mills except between the rolling mills constituting the finish rolling mill 18. The table roll 7 between the finishing mill 18 and the coiler 24 is particularly called a run-out table 23.

  Reference numeral 14 is a crop shear, and 16 is a descaling device. In addition, various sensors for measuring the temperature, dimensions (thickness, width), shape, and the like of the material 8 to be rolled are installed at various locations in the hot rolling line 100. 50 is a control device, 70 is a process computer, and 90 is a business computer.

  FIG. 5A schematically shows the main part of the coiler (winding device) 24 extracted.

  The coiler (winding device) 24 includes a pair of pinch rolls 1, and while the material to be rolled 8 is being wound, the center of the pinch roll 1 b on the other side is centered on the other side of the pinch roll 1 a while the material 8 is being rolled. The material to be rolled 8 to be conveyed is inserted between the pair of pinch rolls 1a and 1b in a state offset in the conveying direction. By doing so, the conveyance direction of the material 8 to be rolled is changed downward in FIG.

  And by rotating the mandrel 2 in a state where the tip of the material 8 to be rolled is wound, tension is applied to the material 8 to be rolled between the pair of pinch rolls 1a and 1b. Wind up to.

  In FIG. 5, it is conveyed between the upper and lower pinch rolls 1a and 1b with the center of the upper pinch roll 1b offset from the center of the lower pinch roll 1a in the conveying direction of the material 8 to be rolled. When the material to be rolled 8 is inserted and the conveyance direction of the material to be rolled 8 is changed downward, the bending moment acting on the material to be rolled 8 when the material 8 is wound by rotating the mandrel 2 at that time. A pre-strain such that a bending moment in the same direction acts is applied to the material 8 to be rolled.

  3 is called a wrapper roll, and before the tip of the material 8 to be rolled approaches, a gap corresponding to the thickness of the material 8 to be rolled is provided between the mandrel 2 and the mandrel 2 as shown in FIG. Is rotated at substantially the same peripheral speed as that of the mandrel 2, and after the tip of the material 8 to be rolled is inserted, as shown in FIG. Retreat to a safe position.

  4 is called a throat guide, and guides the material 8 to be rolled toward the circumferential direction of the mandrel 2 from between the pinch rolls 1a and 1b.

  While winding the material to be rolled 8, by controlling the tension generated between the pinch rolls 1a and 1b and the mandrel 2, the material to be rolled 8 is wound tightly so as not to be loosened or rolled. It is possible to suppress the occurrence of unevenness in the width direction of the material 8, that is, so-called telescoing.

  By the way, it becomes difficult to change the conveyance direction of the to-be-rolled material 8 downward, so that the intensity | strength of the to-be-rolled material 8 becomes high or thickness becomes thick. This is because the bending rigidity of the material 8 to be rolled increases. Moreover, the tension | tensile_strength which can be generate | occur | produced between the pinch rolls 1a and 1b and the mandrel 2 is not enough, so that the intensity | strength of the to-be-rolled material 8 becomes high or thickness becomes thick. For this reason, there exists a problem that winding looseness arises or telescopic occurs.

  In particular, when the rearmost end of the material to be rolled 8 passes through the pinch rolls 1a and 1b, the tail end jumps up, so that the bending moment acting on the material 8 to be rolled and the pre-strain applied are finally reduced. .

  In Patent Document 1 and Patent Document 2, as shown in FIG. 6, a plurality of pairs of pinch rolls 1 a and 1 b are installed to share the generation of tension, and as a result, only a pair of pinch rolls are installed. Trying to secure high tension.

Japanese Patent Application Laid-Open No. 07-275932 JP 2006-281262 A

  However, as described above, the bending rigidity of the material to be rolled increases as the strength of the material to be rolled increases and the thickness increases. For example, the tensile strength at room temperature is 400 MPa or more. When it becomes a high-strength extra-thick material with a thickness exceeding 8 mm, the bending rigidity finally increases, and as shown in exaggeration in FIG. 7, the pair of upper and lower pinch rolls can no longer bend the material to be rolled, and the tension is also high. It becomes impossible to secure enough, and problems such as winding looseness and telescoping become obvious.

  In this regard, even if a plurality of pairs of pinch rolls are installed as in Patent Document 1 and Patent Document 2, significant improvement cannot be expected.

  The present invention was made to solve such problems of the prior art, and even in the case of a high-strength extra-thick material, in a hot rolling line that can prevent the occurrence of loosening of winding or telescopic occurrence. An object is to provide a winding device, a method for winding a material to be rolled in hot rolling, and a method for manufacturing a hot-rolled metal strip.

That is, the present invention is as follows.
(1) a pair of pinch rolls that allow the material to be rolled to be inserted between them;
A mandrel that winds the material to be rolled up to the tail end while applying tension to the material to be rolled between the pair of pinch rolls by rotating the tip of the material to be rolled.
Prior to the tip of the material to be rolled approaching, a gap corresponding to the thickness of the material to be rolled is formed between the mandrel and rotated at substantially the same circumferential speed as the mandrel. In addition, after the tip of the material to be rolled is inserted, a wrapper roll that retreats to a position that does not come into contact with the material to be rolled,
A throat guide for guiding the material to be rolled toward the circumferential direction of the mandrel from between the pair of pinch rolls;
In a winding device in a hot rolling line equipped with
A winding device in a hot rolling line, wherein a guide roll that applies a bending moment in the same direction as a bending moment that the pair of pinch rolls bends the material to be rolled is attached to the pair of pinch rolls.
(2) The material to be rolled that is hot-rolled and conveyed is inserted between a pair of pinch rolls to bend the material to be rolled,
In the winding method of the material to be rolled in hot rolling, by winding the mandrel wound around the tip of the material to be rolled,
While the guide roll attached to the pair of pinch rolls is brought into contact with the material to be rolled, and the bending material in the same direction as the bending moment that the pair of pinch rolls bends the material to be rolled is applied, the material to be rolled is A method for winding a material to be rolled in hot rolling, characterized by winding.
(3) A method for producing a hot-rolled metal strip using the method of (2).

  ADVANTAGE OF THE INVENTION According to this invention, even if it is a high-strength extra-thick material, the winding apparatus in a hot rolling line which can prevent that a winding looseness arises or telescopic production arises, winding of the to-be-rolled material in hot rolling A method and a method for producing a hot-rolled metal strip can be provided.

The diagram for explaining one embodiment of the present invention Diagram for explaining another embodiment of the present invention Diagram for explaining the effect of the present invention Diagram for explaining an example of a hot rolling line Diagram for explaining the prior art Diagram for explaining the prior art Diagram for explaining problems of the prior art

  (Embodiment of First Invention) FIG. 1 shows a winding device in a hot rolling line according to an example of an embodiment of the first invention.

  The winding device 24 in the hot rolling line according to an example of the first embodiment of the present invention shown in FIG. 1 allows the material 8 to be conveyed to pass therethrough, and is already in the center on one side. Between the pair of pinch rolls 1a and 1b by rotating the pair of pinch rolls 1a and 1b whose center on one side is offset in the conveying direction of the material to be rolled 8, and the tip of the material to be rolled 8 being wound. The mandrel 2 that winds up the material 8 to the tail end while applying tension to the material 8 to be rolled and the mandrel 2 before the tip of the material 8 approaches. A gap corresponding to the thickness of the material 8 is created and rotated at substantially the same peripheral speed as the peripheral speed of the mandrel 2, and after the tip of the material 8 is inserted, it does not come into contact with the material 8. A pair of pinches for the wrapper roll 3 retracted to the position and the material 8 to be rolled In the winding device 24 in the hot rolling line 100 or the like described with reference to FIG. 4, for example, with a throat guide 4 that is guided from between the rolls 1 a and 1 b toward the circumferential direction of the mandrel 2, Guide rolls 5a and 5b, which allow the pinch rolls 1a and 1b to apply a bending moment in the same direction as the bending moment for bending the material 8 to be rolled, are attached to the pair of pinch rolls 1a and 1b.

  From the viewpoint of preventing the tail end from jumping up and the bending moment acting on the material 8 to be rolled and the pre-strain applied from the tail end of the material 8 to be rolled up when the rearmost end passes through the pinch rolls 1a and 1b. It is preferable to install the guide rolls 5a and 5b as close to the pinch rolls 1a and 1b as possible, and the upper pinch roll 1b from the position where the guide roll 5a or the guide roll 5b contacts the material 8 to be rolled is used. It is desirable that the distances d1 and d2 to the position in contact with the head be 1000 mm or less.

  (Embodiment of the Second Invention) If the winding device 24 in the hot rolling line according to an example of the embodiment of the first invention described above is used, it is hot rolled and conveyed. The material to be rolled 8 is inserted between a pair of pinch rolls 1a and 1b, and the material to be rolled 8 is bent in a direction having components downward in the example of FIG. In the winding method of the material to be rolled 8 in hot rolling, which is wound by rotating the mandrel 2 wound with the guide rolls 5a and 5b, the guide rolls 5a and 5b attached to the pair of pinch rolls 1a and 1b are applied to the material 8 to be rolled. The material to be rolled 8 is wound while the bending moment in the direction indicated by the thick arrow in FIG. 1 is applied in the same direction as the bending moment in which the pair of pinch rolls 1a and 1b bends the material 8 to be rolled. Can be.

  According to the method of the second aspect of the present invention, it is possible to prevent loose winding or telescopic occurrence even with a high-strength extremely thick material.

  As described above, the present invention is not limited to the example of the embodiment described above. For example, as shown in FIGS. 2A and 2B, the object of the present invention can be achieved even when only one side of the guide rolls 5a and 5b is installed.

  In the embodiment of the present invention shown in FIG. 1, the pinch rolls 1 a and 1 b are offset from the center of one side in the conveyance direction of the material to be rolled 8, while the center of the other side is offset. However, the present invention is not limited to this. For example, the center of the other side is the material to be rolled with respect to the center of one side as in the case of the upstream pinch roll in the conveying direction A of the plurality of pairs of pinch rolls shown in FIG. Even if the present invention is applied to a pinch roll that is not offset in the conveyance direction 8, there is no circumstance that should prevent this.

  The diameter of the lower pinch roll 1a is 500 mm, the diameter of the upper pinch roll 1b is 900 mm, the diameter of the mandrel 2 when winding the material 8 to be rolled is 762 mm, and the diameter of the wrapper roll 3 is 370 mm. When a steel plate with a thickness of 10 mm with a tensile strength at room temperature of 650 MPa is inserted between the upper and lower pinch rolls 1 a and 1 b at 500 ° C., the conveying direction of the material to be rolled 8 is downward. The pre-strain in the same direction as the conveying direction A of the material to be rolled 8, which is applied to the upper surface of the steel plate by changing to the direction having the component, is the outer diameter of the material 8 rolled into a coil shape. Conventionally, when the diameter reaches 2000 mm, as shown in FIG. 3A, the method of the present invention is applied when there is only 0.33% (the plastic strain is only 0.03%).

  The distance from the position where the guide roll 5a or the guide roll 5b is in contact with the material 8 to be rolled to the position where the upper pinch roll 1b is in contact with the material 8 is 800 mm. When the material to be rolled 8 is pushed to the expected passage line (pass line) and a bending moment in the same direction as the bending moment at which the pair of upper and lower pinch rolls 1a and 1b bend the material to be rolled 8 is applied to FIG. As shown, a simulation result can be obtained that can give 1.96% as the pre-strain (plastic strain is 0.30%).

  In FIGS. 3A and 3B, the thin solid line indicates total strain, and the thick solid line indicates plastic strain. As shown in FIG. 3A, in the conventional case, the elastic strain after being wound by the mandrel 2 is 0.30% when the outer diameter of the rolled material 8 wound in a coil shape reaches 2000 mm. Although remaining, as shown in FIG. 3B, when the present invention is applied, only 0.20% remains, and winding looseness and accompanying telescopic are less likely to occur by the difference.

1a, 1b Pinch roll 2 Mandrel 3 Wrapper roll 4 Throat guide 5a, 5b Guide roll 7 Table roll 8 Rolled material 9 Width press 10 Heating furnace 12 Rough rolling mill 13 Edger roll 14 Crop shear 15 Finishing input side thermometer 16 Scaling device 18 Finishing mill 19 Work roll 19A Backup roll 20 Looper 21 Finishing side thermometer 22 Finishing side thickness gauge 23 Runout table 24 Coiler 25 Coiler inlet side thermometer 26 Cooling equipment 50 Control device 70 Process computer 90 Business computer 100 Hot rolling line A Conveying direction

Claims (3)

A pair of pinch rolls that allow the material to be rolled to be inserted between them;
A mandrel that winds the material to be rolled up to the tail end while applying tension to the material to be rolled between the pair of pinch rolls by rotating the tip of the material to be rolled.
Prior to the tip of the material to be rolled approaching, a gap corresponding to the thickness of the material to be rolled is formed between the mandrel and rotated at substantially the same circumferential speed as the mandrel. In addition, after the tip of the material to be rolled is inserted, a wrapper roll that retreats to a position that does not come into contact with the material to be rolled,
A throat guide for guiding the material to be rolled toward the circumferential direction of the mandrel from between the pair of pinch rolls;
In a winding device in a hot rolling line equipped with
A winding device in a hot rolling line, wherein a guide roll that applies a bending moment in the same direction as a bending moment that the pair of pinch rolls bends the material to be rolled is attached to the pair of pinch rolls. The material to be rolled that is hot rolled and conveyed
Bending the material to be rolled by inserting it between a pair of pinch rolls,
In the winding method of the material to be rolled in hot rolling, by winding the mandrel wound around the tip of the material to be rolled,
While the guide roll attached to the pair of pinch rolls is brought into contact with the material to be rolled, and the bending material in the same direction as the bending moment that the pair of pinch rolls bends the material to be rolled is applied, the material to be rolled is A method for winding a material to be rolled in hot rolling, characterized by winding.   A method for producing a hot-rolled metal strip using the method according to claim 2.

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