JP2002178006A - Equipment for rolling thick steel plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thick steel plate rolling equipment with which the occurrence of dents is prevented and the wear resistance of a work roll is improved when rolling a rolled stock with the thick steel plate rolling equipment provided with a light reduction mill. SOLUTION: In the thick steel plate rolling equipment which has at least a finishing mill and a cooling system for cooling a rolled plate which is rolled with the finishing mill and on which the apparatuses of the cooling system are arranged, in this thick steel plate rolling equipment, a device for removing the scale which is stuck to the surface of the rolled stock is arranged at least on the inlet side of the light reduction mill and/or a device for removing the scale which is stuck to the surface of the work roll of the rolling mill is arranged at least on the outlet side of the light reduction mill.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel plate rolling equipment equipped with a light rolling mill equipped with a scale removing and lubricating oil supply device for the purpose of ensuring excellent surface properties of a rolled material and preventing work roll wear. .

[0002]

2. Description of the Related Art In a steel plate rolling facility, that is, a plate rolling mill, a rolled plate after finishing rolling is transferred to a refining process such as shearing, heat treatment, shape correction, and painting through a cooling device and / or a cooling floor. And shipped here as a product. In the refining process, a relatively efficient correction method using a roller leveler and an extremely inefficient correction method using a hydraulic press device are used in combination for plate shape correction. This is because, in the roller leveler, the applicable plate thickness range is limited, and even in the applicable plate thickness range, an irregular plate shape defect that cannot be corrected by the roller leveler may occur. It is. If such plate shape correction can be made more efficient, it will be possible to greatly reduce the manufacturing cost of thick steel plates. For this purpose,
Technical developments concerning plate shape control in finish rolling and uniform cooling control in a cooling device have been carried out, but they have not yet achieved sufficient effects.

[0003] In order to solve such problems of the prior art, attention has been paid to a thick steel plate rolling equipment equipped with a light rolling mill for the purpose of correcting the shape of a sheet. Japanese Patent Application Laid-Open No. 2000-102805 discloses a thick steel sheet rolling equipment. A preferred embodiment of the structure of the light rolling mill in the above is disclosed.

[0004]

Although the plate shape control and the thickness defect are greatly improved by the above-mentioned plate rolling equipment equipped with a light rolling mill, depending on the type of steel, the scale formed on the surface of the plate may be reduced. The scale easily falls off and falls off or sticks to the work roll at the entrance and exit of the rolling mill, and the peeled scale is caught between the work roll and the backup roll of the rolling mill, and a flaw called an indentation flaw occurs. And may cause a new surface defect. When this mark is generated, it is necessary to replace the roll, and the productivity is impaired, and the amount of grinding for the roll increases, and the unit consumption of the roll deteriorates.

[0005] In addition, if there is a scale that is easily peeled, the coefficient of friction during light reduction rolling becomes high, and the roll wear becomes very fast, so that it becomes necessary to frequently replace the roll. Such a problem has caused an increase in manufacturing cost. An object of the present invention is to provide a rolling facility capable of eliminating poor surface properties of a thick steel plate and reducing the roll abrasion so as to be able to straighten it with high efficiency.

[0006]

SUMMARY OF THE INVENTION In order to solve the problems of the prior art as described above, the present invention provides a method for removing scale and lubricating oil, particularly for the purpose of ensuring excellent surface properties of rolled material and preventing work roll wear. The following thick steel plate rolling equipment equipped with a light rolling mill equipped with a supply device is disclosed.

[0007] Claim 1 of the present invention has at least a finishing mill and a cooling device for cooling the rolled sheet rolled by the finishing mill, and at least one light rolling mill downstream of the cooling device. The present invention relates to a thick steel plate rolling facility, characterized in that a device for removing scale adhered to the surface of the rolled material is arranged at least on the entry side of the light reduction rolling mill. A thick steel plate having at least a finishing mill and a cooling device for cooling a rolled sheet rolled by the finishing mill, and having at least one light rolling mill disposed downstream of the cooling device. The rolling equipment is characterized in that a device for removing scale adhered to the work roll surface of the rolling mill is provided at least on the exit side of the light reduction rolling mill. Is At least a finishing rolling mill and a cooling device that cools the rolled sheet rolled by the finishing rolling mill, and a plate rolling mill provided with at least one light rolling mill downstream of the cooling device; A thick steel plate rolling facility characterized in that an apparatus for supplying water or oil or a mixed oil of both water and oil to the surface of the rolled material is provided on the entrance side of the rolling mill. The rolling equipment according to claim 3, wherein a device for removing scale adhered to the surface of the rolled material at least on an input side of the light reduction rolling mill and / or a work of the rolling mill at least on an output side of the light reduction rolling mill. It is a thick steel plate rolling equipment characterized by being provided with a device for removing scale attached to the roll surface, claim 5 of the present invention, the light rolling mill, at least one of the upper and lower roll assembly, It has a mechanism to support the work rolls by divided backup rolls divided into three or more in the direction, and that each divided backup roll is provided with a load detecting device, a pressing-down device and a roll position detecting device independently of each other. The steel plate rolling equipment according to any one of claims 1 to 4, characterized in that:

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be specifically described below. FIG. 1 shows a preferred embodiment of the first, second, third and fourth inventions of the present invention. There are various types of thick steel plate rolling equipment, and at least a finishing mill 1 and a cooling device 2 for cooling a rolled plate rolled by the finishing mill 1, a light rolling mill 3, and a surface of the rolled material. A device having a device 8 for removing scale adhered to a steel sheet is an object of the first invention of the present invention, and further includes a cooling device for cooling at least a finishing mill 1 and a rolled plate rolled by the finishing mill 1 2. A facility provided with a device 7 for removing scale adhered to the surface of the work roll 4 of the rolling mill at least on the exit side of the light rolling mill 3 is a second invention object of the present invention; In addition, at least the finishing mill 1 and the cooling device 2 for the rolled plate rolled by the finishing mill 1 and the entry side of the light rolling mill 3, one of water and oil or water and oil To supply both mixed oils 6 is an object of the third invention of the present invention. In the third invention, a device 8 for removing scale attached to the surface of the rolled material and / or a work roll 4 of the rolling mill is provided. A facility provided with a device 7 for removing scale attached to the surface is a fourth object of the present invention.

As the finish rolling mill 1, a four-high rolling mill having a mechanism for supporting a pair of work rolls with a pair of backup rolls is often used in many cases, but a two-high rolling mill or a multi-high rolling mill having six or more high rolling mills is usually used. There may be. The cooling device 2 is located downstream of the finishing mill 1 and cools the steel plate after the rolling is completed to a predetermined temperature. The cooling device 2 generally uses equipment using water as a refrigerant, but may use other refrigerants. For example, when the rolled plate is cooled only by cooling on the cooling floor, the cooling floor corresponds to the cooling device 2. The finishing mill 1 and the cooling device 2
In some cases, a device such as a roller leveler is provided between the devices.

A light rolling mill 3 is provided downstream of the cooling device 2. FIG. 1 shows a four-high rolling mill having a mechanism in which a pair of work rolls 4 are supported by a pair of backup rolls 5, but may be a two-high rolling mill or a six-high rolling mill. The light rolling mill 3 performs rolling at a rolling reduction smaller than that of the finishing rolling mill 1, and usually operates at a rolling reduction of about 1%. However, when used for the purpose of sheet thickness correction,
A reduction of about 10% may be applied locally. Between the cooling device 2 and the light rolling mill 3, it is preferable to dispose a light rolling reduction machine front rolled material restraining device 9 and a light reduction rolling mill front rolled material forward / reverse transfer device 11. FIG. 1 shows a pinch roll having an upper roll whose diameter is larger than the upper work roll 4 of the light reduction rolling mill 3 as the light rolling reduction machine front rolled material restraining device 9. What is necessary is just to restrain. Therefore, although a small-diameter roll that is not driven may be used, it is more preferable to adopt a structure that can apply tension. Furthermore, it is preferable to provide an upper surface guide between the light reduction rolling mill front rolling material restraining device 9 and the light reduction rolling mill 3 to prevent a biting failure of the leading end of the rolled plate into the light reduction rolling mill 3. The forward / backward transfer device 11 for the rolled material in the front of the light reduction rolling mill is a device for transferring the rolled material in the rolled material advancing direction (forward direction) and in the direction opposite to the rolled material advancing direction (reverse direction). Indicated by rollers. The number of drive rollers is not limited.

A device 8 is provided between the front rolling material restraining device 9 for the light rolling mill and the light rolling mill 3 to remove the scale which is easily removed from the surface of the rolling material. The device 8 for removing the scale adhered to the surface of the rolled material includes a scale for weakly adhered scale generated by a light rolling reduction machine front rolled material restraining device 9, a light reduction rolling mill front rolled material forward and reverse transfer device 11, and the like. And there is no need to completely remove the scale. Large scale of the surface layer peels and falls off at the entry side of the rolling mill during rolling, and this scale adheres to the work roll 4 and the backup roll 5 to prevent indentation flaws particularly generated between the lower work roll and the lower backup roll. Play a role. As a device 8 for removing the scale that easily falls off from the surface of the rolled material, a non-contact type in which a medium such as air or water is sprayed onto a plate surface through a nozzle may be used, or a metal, plastic or fiber may be used. A contact type such as a brush or a wiper using a material such as

A device 6 for supplying one of water and oil or a mixed oil of water and oil to the surface of the rolled material is provided on the entry side of the light rolling mill 3. As the oil, oil having only a lubricating effect, only a rust-preventing effect, or an oil having both a lubricating effect and a rust-preventing effect may be used. The supply system may be a direct system, a recirculation system, or an atomizing system. The purpose of this apparatus is basically to improve the wear resistance of the work roll, but it can also serve as peeling of the above-mentioned weak adhesion scale depending on how it is applied.

Further, a device 7 for removing scale attached to the work roll surface 4 of the rolling mill is provided at least on the exit side of the light rolling mill 3. by this,
A small scale attached to the work roll 4 at the time of rolling is removed, and plays a role of preventing a pressing flaw between the work roll and the backup roll. As a device for removing the scale, a contact type such as a brush or a wiper using a material such as plastic, hard rubber, urethane, or metal may be used, or a non-contact type using high-pressure water or high-pressure air may be used. .

Downstream of the light reduction rolling mill 3, a rear rolling material restraining device 10 for a light reduction rolling mill and a forward / reverse transporting device 12 for a rear rolling material of the light reduction rolling mill are installed. FIG. 1 shows a pinch roll having an upper roll having a diameter larger than the upper work roll of the light reduction rolling mill 8 in the light rolling reduction machine rear surface rolled material restraining apparatus 10. It is not limited to this as long as it is bound. Therefore, although a small-diameter roll that is not driven may be used, it is more preferable to adopt a structure that can apply tension. Further, it is preferable to provide an upper surface guide between the light rolling reduction machine 3 and the light rolling reduction machine 3 between the light rolling reduction machine restraining apparatus 10 and the light reduction rolling mill 8 in order to prevent biting failure of the leading end of the rolled plate into the light reduction rolling mill 8. The rear rolling material forward / reverse transfer device 12 for the rear side of the light rolling mill is a device for transporting the rolled material in a rolled material traveling direction (forward direction) and in a direction opposite to the rolled material traveling direction (reverse direction). It is shown in a roller system. The number of drive rollers is not limited.

In FIG. 1, an apparatus 8 for removing scale is provided.
Is shown as being installed on the upper and lower surfaces, but may be installed on only one surface. Further, between the cooling device 2 and the light rolling mill 8, devices for a plurality of refining processes such as shearing and heat treatment may be provided. Rather, since the shearing and heat treatment steps may cause a change in the shape of the sheet, it is preferable to arrange the steps upstream of the light rolling mill 8. In addition, between the finishing mill 1 and the cooling device 2 and between the cooling device 2 and the light reduction mill 8, a form directly connected by a roller table is preferable from the viewpoint of productivity. It may be in the form of being connected by another transportation means.

Next, FIG. 2 shows a preferred embodiment of the fifth invention of the present invention. There are various types of light reduction mills of the thick steel plate rolling equipment shown in the first, second, third and fourth inventions, and at least one of the upper and lower roll assemblies is divided into three in the axial direction. A mechanism for supporting the work rolls by the divided backup rolls divided as described above, and each of the divided backup rolls is independently provided with a load detection device, a reduction device, and a roll position detection device. Equipment (hereinafter referred to as the intelligent rolling mill 3 ')
Of the invention. FIGS. 3A and 3B show an example of the light rolling intelligent rolling mill 3 '. In this example, the present invention is applied to a case where a rolled material P having a thickness of 5 to 60 mm and a width of 2500 to 4200 mm is lightly rolled. The intelligent rolling mill 3 'of this example has a mechanism in which upper and lower work rolls 4' are supported by divided backup rolls 5 'and 5 "divided into three or more in the axial direction in upper and lower inner housings. And each of the divided backup rolls 5'a to 5'h, 5 "a to 5"
g is independently provided with a load detecting device, a rolling-down mechanism, and a position detecting mechanism. Further, a work roll chock is provided in the inner housing.

On the front and rear sides of the light rolling intelligent rolling mill 3 ', a front rolling material restraining device 9 for a light rolling rolling mill and a rear rolling material restraining device 10 for a light rolling rolling mill are installed.
Between the light rolling reduction machine front rolled material restraining device 9 and the light rolling intelligent rolling mill 3 ', there is provided a device 8 for removing the scale which is attached to the surface of the rolled material and easily falls off. The device 8 for removing the scale adhered to the surface of the rolled material may be generated by the light rolling reduction machine front rolled material restraining device 9, the light reduction rolling mill front rolled material forward / reverse transfer device 11, or the like.
Since the scale having low adhesion is peeled off by the cracks in the surface scale layer, it is not necessary to completely remove the scale. At the time of rolling, large scale of the surface layer peels and falls off at the entry side of the rolling mill, and this scale adheres to the work rolls 4 'and the backup rolls 5' and 5 ", and is generated particularly between the lower work roll and the lower backup roll. The device 8 for removing the scale that easily adheres to the surface of the rolled material and removes the indentation flaw
A non-contact type in which a medium such as air or water is sprayed onto the plate surface via a nozzle may be used, or a contact type such as a brush or a wiper using a material such as metal, plastic, or fiber may be used.

Also, on the entry side of the light reduction intelligent rolling mill 3 ',
A device 6 for supplying water or oil or a mixed oil of water and oil to the surface of the rolled material is provided. As the oil, only a lubricating effect, only a rust preventing effect, or an oil having both a lubricating effect and a rust preventing effect may be used. The supply system may be a direct system, a recirculation system, or an atomizing system. The purpose of this apparatus is basically to improve the wear resistance of the work roll, but it can also serve as peeling of the above-mentioned weak adhesion scale depending on how it is applied.

Further, a device 7 for removing scale adhered to the work roll surface 4 'of the rolling mill is provided at least on the exit side of the intelligent rolling mill 3'. This serves to remove small scales adhering to the work roll 4 'during rolling, and to prevent press flaws between the work roll and the backup roll. As a device for removing the scale, a contact type such as a brush or a wiper using a material such as plastic, hard rubber, urethane, or metal may be used, or a non-contact type using high-pressure water or high-pressure air may be used. .

By using this intelligent rolling mill, for example, Japanese Patent Application Laid-Open No. 6-262228 filed by the inventors
By using the method disclosed in Japanese Patent Application Laid-Open Publication No. H11-115, it is possible to manufacture a product having excellent flatness in addition to the above-described effects.

[0021]

EXAMPLES Examples of the present invention are shown below. As the light rolling mill used, the thick steel plate rolling equipment shown in FIG. 2 was used. The light rolling mill 3 'is a light rolling intelligent rolling mill 3' shown in FIG.
Is the same as Although not shown, the light reduction intelligent rolling mill 3 'uses a pass line adjuster (a device for adjusting a pass line corresponding to a change in roll diameter when a roll is replaced) by an electric motor and a hydraulic reduction. Split backup rolls 5 ', 5 "with a diameter of 750 mm and a body length of 300 mm divided into 15 parts in the upper and lower inner housings which are moved up and down by the main lowering device (the lowering position is measured by detecting the position of the hydraulic cylinder). Has a mechanism for supporting upper and lower work rolls 4 'having a diameter of 350 mm and a body length of 4500 mm, and each of the divided backup rolls 5'a to 5'a to
Each of 5'h, 5 "a to 5" g is independently provided with a load detecting device, a pressing-down mechanism, and a position detecting mechanism.

Although not shown, the upper and lower work rolls 4 'are supplied with torque required for rolling by a drive motor. Further, a work roll chock is provided in the inner housing. The lightly-reduced intelligent machine rear-surface rolled material forward / reverse transport device 12 is a device for transporting a rolled material in a rolled material traveling direction (forward direction) and in a direction opposite to the rolled material traveling direction (reverse direction), and is a driving roller. On the front and rear surfaces of the light rolling intelligent rolling mill 3 ', a front rolling material restraining device 9 and a rear rolling material restraining device 10 for a light rolling rolling mill are installed, respectively. Is composed of a pair of upper and lower rolls 9 and 10 having a diameter of 500 mm and a body length of 4500 mm. Although not shown, these guide rolls are housed in an inner guide roll housing. The inner guide roll housing is supported by the guide roll housing, and can be moved up and down by upper and lower hydraulic cylinders provided in the guide roll housing. Further, although not shown, the electric motors installed above and below the inner guide roll housing enable measurement and adjustment of the upper and lower guide roll gaps, and these guide rolls are designed to prevent slippage with the rolled material. It is driving.

A device 8 is provided between the light rolling reduction machine front rolled material restraining device 9 and the light rolling intelligent rolling mill 3 'to remove scales which are easily removed from the surface of the rolling material. The device 8 for removing the scale adhered to the surface of the rolled material may be generated by the light rolling reduction machine front rolled material restraining device 9 or the light reduction rolling mill front rolled material forward / reverse transfer device 11 or the like. The peeling of the scale with weak adhesion due to the entered cracks does not remove the scale completely, but the scale of the large surface layer peels off at the rolling mill entry side during rolling, and the peeled scale becomes the work roll 4 '. And a role to prevent press-in flaws generated particularly between the lower work roll and the lower backup roll. A device for removing scale adhered to the surface of the rolled material. As No. 8, a non-contact type sprayed to the plate surface via air was used.

Also, on the entry side of the light reduction intelligent rolling mill 3 ',
A device 6 for supplying water or a mixed oil of water and oil is provided on the surface of the rolled material. Industrial water was used as the water, and a recirculation method was used with a mineral rolling lubricating oil having an emulsion concentration of 1% as a mixed oil of water and oil.

Further, a device 7 for removing the scale adhered to the work roll surface 4 'of the rolling mill is provided at least on the exit side of the intelligent rolling mill 3'. In this way, small scales adhered to the work rolls during rolling are removed to prevent the occurrence of indentation flaws between the work rolls 4 'and the backup rolls 5' and 5 ". A contact type with a wiper using a material was used.

The rolled material has a thickness of 20 mm and a width of 250
0-4000 mm, low carbon steel (proof strength: about 412 MPa) was used. In order to confirm each effect, rolling was carried out under various conditions, and each effect was verified. Table 1 shows the results. In Table 1, as a criterion, there is a device 8 for removing the scale, a device 6 for supplying water or a mixed oil of water and oil to the surface of the rolled material, and an indentation flaw when the device 7 for removing the scale is not used. The rate and roll wear were evaluated as 100%. According to the present invention, it has been confirmed that the plate shape is flat from the leading end to the trailing end of the rolled material, the occurrence of indentation flaws can be prevented and the wear resistance of the work roll can be significantly improved as compared with the conventional case.

[0027]

[Table 1]

[0028]

As described above, the flatness and surface properties of the end portion of the thick steel plate and the wear resistance of the work roll are remarkably improved by using the steel plate rolling equipment of the present invention described above. As a result, the manufacturing cost of thick steel plates can be significantly reduced, and the construction period can be shortened.

[Brief description of the drawings]

FIG. 1 is a diagram showing a preferred embodiment of first to fourth inventions of the present invention.

FIG. 2 is a diagram showing a preferred embodiment of the fifth invention of the present invention.

FIG. 3 shows an example of a light rolling intelligent rolling mill in FIG. 2;
(A) is a rolling mill part, and (b) is a divided backup row.
Is shown.

[Description of Signs] 1 Finishing rolling mill 2 Cooling device 3, 3 'Light rolling mill 4, 4' Work roll 5, 5 ', 5 "Backup roll 6 Apparatus for supplying water or oil or mixed oil of water and oil 7 Apparatus for removing scale adhering to the surface of a work roll 8 Apparatus for removing scale adhering to the surface of a rolled material 9 Light rolling reduction machine front rolled material restraining device 10 Light rolling reduction machine rear rolling material restraining device 11 Light rolling reduction Forward / reverse transfer device for front rolled material 12 Forward / reverse transfer device for rear rolled material on light rolling mill P Rolled material

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) B21C 51/00 B21C 51/00 N

Claims (5)

[Claims] 1. A thick steel plate rolling machine having at least a finishing mill and a cooling device for cooling a rolled sheet rolled by the finishing mill, and at least one light rolling mill arranged downstream of the cooling device. A thick steel plate rolling facility, wherein a device for removing scale adhered to the surface of the rolled material is arranged at least on an entry side of the light rolling mill. 2. A thick steel plate rolling machine having at least a finishing mill and a cooling device for cooling a rolled sheet rolled by the finishing mill, and at least one light rolling mill arranged downstream of the cooling device. A thick steel plate rolling plant, wherein a device for removing scale adhered to a work roll surface of the rolling mill is provided at least on an outlet side of the light rolling mill. 3. A steel plate rolling equipment having at least a finishing mill and a cooling device for cooling a rolled sheet rolled by the finishing mill, and having at least one light reduction mill arranged downstream of the cooling device. 3. A thick steel plate rolling facility, characterized in that a device for supplying water or oil or a mixed oil of both water and oil to the surface of the rolled material is provided at least on the entry side of the rolling mill. 4. The rolling equipment according to claim 3, wherein a device for removing scale adhering to the surface of the rolled material at least on an input side of the light reduction rolling mill and / or a device for removing scale attached to the surface of the light reduction rolling mill. A steel plate rolling equipment provided with a device for removing scale adhering to a work roll surface of a rolling mill. 5. The light rolling mill according to claim 1, wherein at least one of the upper and lower roll assemblies has a mechanism for supporting a work roll by a split backup roll divided into three or more in an axial direction. Wherein a load detecting device, a rolling-down device, and a roll position detecting device are provided independently of each other.
The thick steel plate rolling equipment according to any one of claims 4 to 4.