JP3285487B2 - Coil box - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coil box, and more particularly, to a coil box capable of reducing a coil temperature drop.

[0002]

2. Description of the Related Art In a hot strip mill in which a thin plate is hot rolled, a rolled material (hereinafter referred to as a bar material) is wound once after rough rolling to form a coil, and then unwound to perform finish rolling. A coil box is used.

[0003] Since the bar material wound by the coil box is then subjected to hot finish rolling, it is necessary to prevent the temperature from decreasing over the entire length and width of the coil. For this reason, it is important to prevent the temperature of the inner surface and the end surface of the wound coil from decreasing.

[0004] In order to prevent the coil from being heated in the coil box, the following points must be considered. That is, since the rolling speed of the rough rolling is as fast as 240 m / min, the winding time of the bar material having a length of 40 to 90 m is generally about 10 to 22.5 sec. It is short. And the bar material is a crane composed of two rolls.
Wound on a roll without a mandrel. The wound coil has a mandrel inserted into its inner diameter,
The mandrel is turned around the center of rotation and transferred onto the cradle roller at the rewind position. Normally, rewinding is started before the coil is transferred. The coil is supported from both end faces by two mandrels. The unwinding time was 4 m since the speed on the entry side of the finishing mill was as slow as 60 m / min.
It is as long as 0 to 90 sec. Also, during rewinding, it is necessary to rewind the coil with the mandrel inserted into the inner diameter of the coil so that the coil is not carried to the finish rolling mill side.

[0005] When a cold mandrel is inserted into the coil, the temperature of the inner diameter of the coil decreases. Therefore, for example, as described in JP-A-3-193217, a method is known in which an electric heater is built in a mandrel of a coil box. Although the purpose is different from that of the coil box, Japanese Patent Application Laid-Open No. 3-47624 and
As described in Japanese Patent No. 17153, there is known a method in which a drum for winding a hot-rolled thin plate during finish rolling or rolling is heated in advance, and this method may be applied to a coil box. The method described in Japanese Patent Application Laid-Open No. 3-47624 is a method in which a winding drum is heated in advance by a combustion gas, and the method described in Japanese Patent Application Laid-Open No. 58-17153 discloses a method for winding a drum. Is previously heated electrically.

As a method for preventing heat from the end face of the coil wound around the coil box, for example, as described in JP-A-60-115305 and JP-A-3-193217, There is known a method of heating the same with a burner.

[0007]

First, a description will be given of the temperature drop in the inner diameter portion of the coil.
As described in Japanese Patent Application Laid-Open Publication No. H10-209, the system in which the electric heater is built in the mandrel of the coil box has a structure in which the heater is built in the mandrel itself, and thus has a problem that the strength of the mandrel is reduced.

Further, the methods described in JP-A-3-47624 and JP-A-58-17153 have different purposes from those of the coil box, and cannot be applied to the coil box as it is. That is, in either method, the position of the winding drum is fixed, and a heating device using a combustion gas or a heater is moved forward and backward with respect to the fixed winding drum to heat the winding drum. It is. However, in the coil box, the mandrel is not applicable to the coil box because the mandrel has a structure of turning to move the wound coil from the winding position to the unwinding position. In particular, in the case of a double mandrel in which two mandrels are inserted from both ends of the coil to support the coil, there is no appropriate position for disposing the heating device as in the above-described conventional method, and therefore, it cannot be applied as it is. Things.

Therefore, the conventional method has a problem that it is not possible to effectively prevent a temperature drop in the inner diameter portion of the coil.

Next, the prevention of the temperature drop at the end face of the coil will be described. The coil is transferred from the coil winding position to the coil rewinding position by the mandrel, and this is performed by the turning operation of the mandrel. Therefore,
The area where the mandrel turns is disclosed in Japanese Patent Application Laid-Open No. 60-1153.
There is a problem that a burner for heating the end face of the coil as described in Japanese Patent Application Laid-Open No. 2005-193217 or Japanese Patent Application Laid-Open No. 3-193217 cannot be installed, and the temperature drop in this region is not sufficiently prevented.

In particular, since the coil is rewound while the bottom surface thereof is supported by two cradle rollers, the diameter of the coil gradually decreases as the rewound proceeds. Looking at the temperature drop at the end of the coil, the time required for finish rolling is longer at the inner diameter portion than at the outer diameter portion of the coil end portion, so that the temperature drop is remarkable. However, since the center position of the inner diameter portion of the coil end surface changes with rewinding, if the heating position is fixed as in the related art, the coil end portion that needs to be effectively heated is required. The inner diameter cannot be heated.

[0012]

An object of the present invention is to provide a coil box that can effectively heat even the inner end portion of the coil end portion during rewinding, thereby preventing a temperature drop.

[0014]

[0015]

[0016]

[0017]

In order to achieve the above-mentioned object, the present invention is directed to a method of moving a coil made of a high-temperature bar material wound in a coil shape at a winding position in the direction of the inner diameter of the coil. A mandrel inserted into the inner diameter of the coil,
A turning means for turning and transferring the coil from the winding position to the rewinding position while the mandrel is inserted in the coil, and a coil box for performing a rewinding operation at the rewinding position; It turns with the turning means, and is provided with end face heating means for heating the end face of the coil. With such a configuration,
Since the end face heating means turns together with the turning means, the inner diameter portion of the coil can be efficiently heated.

In the above-mentioned coil box, preferably, the above-mentioned end face heating means is further provided with end face heating and retreating means for moving forward and backward with respect to the coil end face. Heating can be performed.

In the above coil box, preferably, the end face heating means includes first end face heating means for heating the vicinity of the inner diameter of the coil, and second end face for heating a position remote from the inner diameter of the coil. And a heating means. Particularly, the inner diameter of the coil can be heated.

In the above-mentioned coil box, it is preferable that an end face of the coil transferred to the unwinding position is further provided in the unwinding position and in an area outside the turning area of the end surface heating means. The heat insulating wall is provided so as to be opposed to the heat insulating wall, and the heat insulating wall can reduce heat radiation from the coil.

[0021] In the coil box, carp preferably further the heat insulating wall with respect to the coil end surface
And a first heat insulating wall advancing / retreating means which advances / retreats in the width direction of the shell.

In the coil box, preferably, the heat insulating wall covers a part of an upper portion of the coil transferred to the rewind position.

In the above-mentioned coil box, it is preferable that the coil box is provided with a second heat insulating wall retracting means for retreating the heat insulating wall covering the upper part of the coil from the position of the coil in the line direction. is there.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is an overall configuration diagram of a hot strip mill according to an embodiment of the present invention.

The slab 62 (having a width of 600 to 2200 mm) having a thickness of 200 to 250 mm is formed by
It is rolled into a bar material 2 having a thickness of 40 mm. Bar material 2 is tape
It is conveyed by the bull roller 3 and wound up by the coil box 90. The coil box 90 pushes the bar material 2 upward by the entry shoe 4 and performs bending by the bending roller 3 composed of three rollers.
The coil 6 is formed on the cradle roller 7. The formed coil 6 is supported by the mandrel 8. The mandrel 8 has an arm 9 around a pivot shaft 11 of a stand 10.
It has a structure that is turned. The coil 6 supported by the mandrel 8 is turned by the arm 9 and transferred to the rewind cradle 13.

The transferred coil 12 is rewound, and
The unwound bar material 64 is moved by the pinch leveler 14.
Straightened. The tail end of the preceding bar member 65 and the leading end of the following bar member 64 in the straightened bar members are sheared by the shearing machine 15, and both are joined by the joining machine 16. The joined bar material is continuously rolled by a finishing mill 17 to produce a hot-rolled thin plate 18.

Next, the heating structure of the mandrel in the coil box will be described with reference to FIG. FIG. 2 is a plan view showing a partial cross section of the coil box according to one embodiment of the present invention.

The bar material conveyed from the direction of arrow A is
It is wound up by a coil box and is mounted as a coil 6 on a cradle roller (not shown). The width of the wound coil is 2200 m of the coil 6 indicated by a solid line.
The coils 19-6 indicated by the dashed line
Various widths are wound up to as narrow as 00 mm. Coil diameter is 2,500 m with wide coil 6
m, the diameter of the coil 19 having a narrow width is about φ1500 mm.

At the time of transferring the coils 6 and 19, the mandrel 8 is inserted from both end faces of the coil 6 into the inner diameter 66 of the coil indicated by the broken line, and transferred to the rewinding side (indicated by a two-dot chain line on the right side in the figure). Is done. The transferred coil 12 is rewound and transported in the direction of arrow B, and a thin plate is manufactured by the finish rolling mill.

Next, the structure for inserting and turning the mandrel 8 will be described. The mandrel 8 has coils 6, 19
Are inserted independently from both ends of the coil so that they are inserted from both end faces of the coil. However, since both are symmetrical structures, only one of them will be described here.

The mandrel 8 has two bearings 24, 24 '.
Thereby, it is rotatably supported inside the inner cylindrical shaft 26. The inner cylindrical shaft 26 is formed by two bearings 25, 25 '.
It is slidably supported inside the outer cylindrical shaft 23 in the thrust direction. An end cover 27 is provided at one end of the inner cylindrical shaft 26.
Are fixed, and a bracket 30 is fixed to the end cover 27. A cylinder 28 is attached to the bracket 30. When the cylinder 28 operates in the direction of arrow C, the inner cylindrical shaft 26 is
3, the tip of the mandrel 8 moves in the direction of arrow D and is inserted into the inner diameter portions 66 of the coils 6 and 19.

Although the tip of the mandrel 8 is exposed,
The outer periphery of the base is covered by a heat insulating ring 22.
The insertion length of the mandrel 8 into the coil inner diameter 66 is a portion at the tip of the heat insulating ring 22 covering the mandrel 8.

The outer cylindrical shaft 23 has two arms 33, 36.
Has been fixed by. The arms 33 and 36 are fixed to two bosses 34. The bosses 34 are each fixed to the turning shaft 11. The pivot 11 is rotatably supported by two stands 10, 10 '. One end of the turning shaft 11 is connected to a pair of cylinders 35, 35 '.
Is engaged. Rack gears attached to the ends of the cylinders 35 and 35 'are configured to engage with pinion gears attached to one end of the pivot shaft 11, respectively, and drive the cylinders 35 and 35' in opposite directions. By transmitting the movement to the turning shaft 11 via the rack gear and the pinion gear, the turning shaft 11
Can be rotated in the direction of arrow E. Therefore, when the cylinder 11 is operated, the turning shaft 11 is turned, and the mandrel 8 supported by the outer cylindrical shaft 23 and the inner cylindrical shaft 26 is turned. Are transferred like a coil 12 indicated by a circle.

In the present embodiment, the mandrel 8 inserted into the inner diameter portion 66 of the coil is structured to be heated before insertion into the coil. That is, the temperature of the coil is 1100
This is because when the mandrel 8 at normal temperature is inserted into and brought into contact with the mandrel, a significant temperature drop occurs in the inner diameter portion of the coil in contact with the mandrel.

At the position where the mandrel 8 is retracted, the tip of the mandrel 8, that is, the coil supporting portion of the mandrel 8, is included in the heating furnace 80. Heating furnace 8
Reference numeral 0 denotes an iron shell 20 and an inner refractory 21 fixed inside the iron shell 20. The heating furnace 80 has a bar
A corner 41 is provided. The combustion flame 44 ejected from the burner 41 flows between the mandrel 8 and the refractory 21 to heat the mandrel 8 to about 800 ° C. Since the temperature of the coil is 1100 ° C. to 950 ° C., it is preferable that the mandrel 8 is also heated to the same temperature. I try to heat it. Therefore, a temperature difference occurs between the coil and the heated mandrel 8, but since the temperature difference is smaller than when the mandrel 8 is at room temperature, the mandrel 8 contacts the inner diameter portion 66 of the coil. However, the inner diameter portion 66 of the coil is
Temperature can be prevented.

The driving force of the motor 29 is transmitted to the other end of the mandrel 8 via belt transmission mechanisms 31 and 32. Mandrel 8 has bearings 25 and 2
It is rotatably supported by 5 ', and the mandrel 8 can be rotated by the motor 29, thereby preventing the partial heating of the mandrel 8. The rotation of the mandrel 8 is performed when the tip of the mandrel 8 is at a position where the mandrel 8 is heated by the burner 41 shown. Although one burner is provided, a plurality of burners may be provided, and when the number of burners is large, the mandrel can be heated relatively uniformly, so that a mandrel rotating mechanism is not required. Good.

The heating furnace 80 is supported by an arm 81. A refractory 21a is attached to a surface of the arm 81 opposite to the coils 6 and 19 so as to prevent radiant heat from the coils 6 and 19.

The arm 81 is fixed to a boss 82, and a shaft 39 is attached to the boss 82. Axis 39
Is slidably supported in the turning shaft 11. The cylinder 40 is mounted between the arm 81 and the boss 34. By operating the cylinder 40, the arm 81 can slide in the direction of arrow F, that is, in the direction of the end face of the coil.

When the width of the coil is wide like the coil 6, the cylinder 40 is not driven, and when the tip of the mandrel 8 is inserted into the inner diameter 66 of the coil 6, only the cylinder 28 is driven. Is driven, and the mandrel 8 slides in the direction of arrow D. However, when the width of the coil is narrow like the coil 19, the cylinder 28 is driven to protrude the mandrel 8 from the steel 20 by a predetermined amount, and then the cylinder 28 and the cylinder 40 are simultaneously driven. Then, the mandrel 8 and the arm 81 are simultaneously moved in the directions of the arrows D and F while the mandrel 8 is projected from the steel shell 20 and inserted into the inner diameter portion 66 of the narrow coil 19.

This is because the mandrel 8 has a narrow coil 19.
When the inner cylindrical shaft 26 is slid with a large stroke in the outer cylindrical shaft 23 when the inner cylindrical shaft 26 is inserted into the inner cylindrical portion 66, the heating furnace 80 and the inner cylindrical shaft 26 interfere with each other. To prevent this interference, the coil support of the mandrel 8 and the inner cylindrical shaft 26
When the heat insulating ring 22 provided therebetween is inserted into the heating furnace 80, the heating furnace 80 is pushed out to the coil end face side in synchronization with the mandrel 8 by the cylinder 40 to avoid interference.

The heating furnace 80 can move forward and backward in the direction of the coil end face. However, if the difference in the coil width is small, the heating furnace 80 may be fixed.

As described above, since the mandrel of the coil box is heated before being inserted into the inner diameter of the coil, even when the mandrel is inserted into the inner diameter of the coil, the temperature drop at the inner diameter of the coil is reduced. can do.

As a method of heating the mandrel, when the mandrel portion supporting the coil is retracted, this portion is enclosed in a heating furnace and heated, so that the temperature can be sufficiently increased before the coil is supported and transferred. In addition, when the inner diameter portion of the coil is supported, a decrease in temperature of the inner diameter portion of the coil can be reduced.

Further, the total length of the mandrel to be inserted can be shortened, and the time for inserting the mandrel into the inner diameter of the coil can be shortened. That is, if the temperature of the mandrel is low, the temperature of the coil drops only in the portion in contact with the mandrel, and if the mandrel is short, the temperature varies in the air inside the coil. In contrast to the need to insert a mandrel, by preheating the mandrel, even if a short mandrel is inserted, the temperature of the inner diameter of the coil does not drop, so the total length of the inserted mandrel can be shortened. is there.

The heating furnace is provided at a position retracted from the coil position, and the mandrel is heated by the heating furnace, so that interference between the heating furnace and the coil does not occur.

Further, since the heating of the mandrel is performed while idling, the mandrel does not become unevenly heated.

Further, since the heating furnace for the mandrel can move forward and backward with respect to the coil end face, it does not interfere with the member supporting the mandrel and can prevent the mandrel from being lengthened.

Further, since the heating furnace of the mandrel is structured so as to rotate simultaneously with the rotation of the mandrel, the heating furnace can be installed in a double mandrel type coil supporting coil box without interference between the heating furnace and the coil.

Further, since the mandrel employs a method in which the mandrel is heated from outside by a heating furnace, the strength of the mandrel does not decrease as in the method in which a heater is provided inside the mandrel.

Next, a method for preventing a temperature drop of the coil end surface will be described with reference to FIGS. FIG. 3 is a view as viewed in the direction of arrows XX in FIG. FIG. 4 is a view taken in the direction of the arrow YY in a state where the mandrel 8 has turned around the turning shaft 11 in the direction of the arrow E from the state shown in FIG.

First, a method of heating a coil end face by a burner will be described. In FIG. 3, the arm 81 is attached to the shaft 39, and the shaft 39 is slidable with respect to the turning shaft 11. At the tip of the arm 81,
An iron shell 21 is fixed, and a heat-resistant material 2 is provided on an inner peripheral surface of the iron shell 21.
0 is attached. The mandrel 8 is heated by the burner 41 attached to the arm 41.

The arm 81 has two burners 4.
2a and 42b are attached. Burners 42a, 4
From 2b, circular fuel flames 45a and 45b indicated by broken lines are ejected toward the end face of the coil to heat the end face of the coil. The burner 42a is arranged near the mandrel 8, and the burner 42b is arranged near the axis 39. Therefore, as shown in FIG. 4, the burner 42a heats the position near the inner diameter portion of the end face of the coil, and
2b heats the position near the outer diameter part.

When the diameter of the coil 12 is large, the burner 4
2b is also used, but when the coil 12 becomes smaller in diameter,
The combustion of the burner 42b is stopped. And the coil 12
The burner 42a for heating the end near the inner diameter of the coil is used to continue heating the coil end surface until the end of coil rewinding.

The rewinding coil 12 is placed on the two cradle rollers 13. As the rewinding of the coil 12 proceeds, the outer diameter of the coil 12 becomes smaller, and the arm 81 becomes , In the direction of arrow G. As the arm rotates, the position of the inner diameter portion of the coil 12 also gradually moves to a position closer to the cradle roller 13. Therefore, if the position of the burner for heating the coil end face is fixed, it is difficult to effectively heat the vicinity of the inner diameter portion of the coil, which is most affected by the temperature drop, but the arm that rotates together with the rewinding of the coil is difficult. By providing the burner 42 on 81,
It is possible to efficiently heat the coil end face, particularly in the vicinity of the inner diameter portion.

Next, a method for reducing the heat radiation from the coil end face will be described with reference to FIGS. As shown in FIG. 4, at the rewind position of the coil 12, the coil 12 for rewinding the two cradle rollers 13 is placed. The cover 52 is arranged close to the end face of the coil 12 to suppress heat radiation from the end face of the coil 12. The covers 52 are arranged on both end surfaces of the coil 12 as shown in FIG. A heat-resistant material is attached to the inner surface of the cover 52. The cover 52 is provided in an area other than the space through which the heating furnace attached to the arm 81 and the arm 18 passes when the mandrel 8 rotates.

The bracket 51 is located above the cover 52.
And an upper cover 48 that can be retracted in the direction of the arrow H by a cylinder 49 via a joint 50 is provided. Since the upper cover 48 covers the upper surface of the coil 12, the effect of preventing heat radiation is large. Although the cover 48 covers a part of the upper surface of the coil 12 in FIG. 2, the area of the cover can be further increased.

When the coil is turned from the winding position to the rewinding position, the cover 48 is retracted in the direction of arrow H by the cylinder 49. In the event of an accident, the coil 1
Since it is necessary to carry out the material 2 out of the line with a crane or the like, the upper cover 48 can be retracted in the line traveling direction (H direction) by the cylinder 49.

The covers 52 and 48 operate the support rods 46 and 46 ′ supported by the bearing 47 by the cylinder 53,
It is adapted to the width of the coil.

As described above, since the coil end face and the heat retaining wall on the coil upper portion are provided in a region where the mandrel heating furnace does not pass when the mandrel heating furnace rotates at the coil rewinding position, the coil has a large heat retaining effect.

Further, since the upper heat retaining wall of the coil can be retracted in the traveling direction of the bar material, it does not hinder the turning of the coil and does not hinder the unloading of the coil in the event of an accident.

Next, a coil box according to another embodiment of the present invention will be described with reference to FIG. FIG.
FIG. 7 is a plan view of a coil box according to another embodiment of the present invention. Note that the same reference numerals as those in FIG. 2 indicate the same parts.

The cylinder 60 is mounted between the arm 81 and the arm 36. By driving the cylinder 60, the arm 81 slides in the direction of arrow F ',
The arm 81 can be brought close to the end faces of the coils 6 and 19.

[0063]

[0064]

According to the present invention, it is possible to effectively heat even the inner end portion of the coil end portion during rewinding, thereby preventing a temperature drop.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a hot strip mill according to an embodiment of the present invention.

FIG. 2 is a plan view showing a partial cross section of the coil box according to one embodiment of the present invention.

FIG. 3 is a view as viewed in the direction of arrows XX in FIG. 2;

FIG. 4 shows a state in which the mandrel 8 is moved from the state shown in FIG.
FIG. 7 is a view taken in the direction of the arrow YY in a state of turning in the direction of the arrow E around the center.

FIG. 5 is a plan view showing a partial cross section of a coil box according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 5 ... Bend den roller 6, 12, 19 ... Coil 7 ... Cradle roller 8 ... Mandrel 11 ... Revolving shaft 13 ... Rewinding cradle roller 20 ... Iron shell 21 ... Heat resistant material 23 ... Outer cylindrical shaft 26 ... Inner cylindrical shaft 28,35,35 ', 40,49,53,60 ... Cylinder 29 ... Motor 41,42a, 42b ... Burner 48,52 ... Cover 66 ... Inner diameter part 81 ... Arm 90 ... Coil box

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Shigeru Nishibayashi 20-1 Shintomi, Futtsu-shi, Chiba Nippon Steel Corporation Technology Development Division (56) References JP-A-3-193217 (JP, A) ( 58) Field surveyed (Int. Cl. ⁷ , DB name) B21C 47/28 B21B 45/00 B21C 47/24

Claims (7)

(57) [Claims] 1. A mandrel which is movable in the direction of the inner diameter of a coil made of a high-temperature bar material wound in a coil shape at a winding position, and which is inserted into the inner diameter of the coil; And a turning means for turning and transferring the coil from the winding position to the rewind position in a state where the coil is inserted into the coil box. A coil box provided with an end face heating means for heating an end face of the coil. 2. The coil box according to claim 1, further comprising end face heating means for moving the end face heating means back and forth with respect to the coil end face. 3. The coil box according to claim 1, wherein the end face heating means heats a portion of the coil near an inner diameter portion, and a first end face heating means heats a position distant from the inner diameter portion of the coil. 2. A coil box, comprising: an end surface heating means according to claim 2; 4. The coil box according to claim 1, further comprising: a coil transferred to the unwinding position in the unwinding position and in an area outside a turning area of the end surface heating means. A coil box, comprising: a heat insulating wall disposed opposite to an end face of the coil box; and the heat insulating wall reduces heat radiation from the coil. 5. The coil box according to claim 4, further comprising a first heat insulating wall advance / retreat means for moving the heat insulating wall forward / backward with respect to the coil end surface in the width direction of the coil. And coil box. 6. The coil box according to claim 4, wherein said heat insulating wall covers a part of an upper portion of said coil transferred to said rewind position. 7. The coil box according to claim 6, further comprising a second heat insulating wall retracting means for retreating the heat insulating wall covering an upper part of the coil from the position of the coil in a line direction. A coil box.