JP2010253510A - Conveying role, conveying apparatus and hot-rolling apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conveying role, a conveying apparatus and a hot-rolling apparatus which allow the costs for maintenance and replacement or the like of the conveying role to be reduced and also suppress a deterioration in quality of a conveyed article. <P>SOLUTION: The conveying role 51 (61) is used for conveying the conveyed article Y, and employs an approximately columnar base material 52 (62) having heat resistance. The conveying role 51 (61) includes covering layers 53 (63) having higher heat resistance and wear resistance than that of the base material 52 (62) and disposed at the outer peripheral surface of the base material 52 (62). The covering layers 53 (63) are provided respectively at positions corresponding to both edge parts of the conveyed article Y in the axial direction of the conveying role 51 (61). <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

 The present invention relates to a transport roll, a transport apparatus, and a hot rolling apparatus.

 Conventionally, a hot rolling apparatus for producing a metal plate or the like from a material such as metal by hot rolling has been used. Moreover, the conveyance apparatus which is equipped with this hot rolling apparatus and conveys the said heated material, and the conveyance roll which is equipped with this conveyance apparatus and supports the said material is used.

By the way, a metal oxide generated by heating, so-called oxide scale, adheres to the surface of the material in the hot rolling apparatus. The oxide scale peels off from the surface during the conveyance of the material, adheres to the outer peripheral surface of the conveyance roll, and is welded by heat, thereby forming a projection called build-up. This build-up caused a scratch or the like on the surface of the material, leading to a deterioration in the quality of the manufactured metal plate or the like.
Therefore, a transport roll having an outer peripheral surface with excellent machinability is used (see, for example, Patent Document 1). The outer peripheral surface of a conveyance roll is ground because the said material and conveyance roll contact during conveyance. And the buildup formed in the outer peripheral surface was removed with grinding of the outer peripheral surface.

Japanese Patent No. 2650774

However, since the outer peripheral surface of the transport roll is a material with excellent machinability, the transport roll is likely to be worn, maintenance and replacement work of the transport roll frequently occurs, and the cost increases. was there.
Furthermore, the grinding powder generated by grinding the outer peripheral surface of the transport roll again adheres to and welds to the outer peripheral surface of the transport roll to form a new build-up at another location.

 This invention is made in view of such a situation, and while reducing the cost of maintenance, replacement, etc. of a conveyance roll, the conveyance roll, conveyance apparatus, and hot rolling apparatus which can suppress the quality deterioration of a conveyed product are provided. The purpose is to provide.

In order to solve the above problems, the present invention employs the following means.
The transport roll of the present invention is a transport roll that is used for transporting a transported object and has a heat resistance and uses a substantially cylindrical base material, and is provided on the outer peripheral surface of the base material, and has heat resistance and wear resistance. The coating layer is provided, and the coating layer is provided corresponding to both edge portions of the conveyed product in the axial direction of the transport roll.
In general, the pressure applied to the outer peripheral surface of the transport roll from both edges in the axial direction of the transported object is greater than the pressure applied from the central part of the transported object, so the transport rolls corresponding to the both edges The outer peripheral surface wears faster than the outer peripheral surface corresponding to the central portion. Here, in the present invention employing the above-described configuration, since the outer peripheral surface corresponding to the both edge portions of the transport roll is provided with a coating layer having wear resistance, the outer peripheral surface of the transport roll becomes difficult to be ground, and grinding is performed. The resulting grinding powder is reduced.

In addition, the transport roll of the present invention adopts a configuration in which the coating layer has an MCrAlX alloy (where M is at least one of Ni, Co and Fe, and X is an element other than M, Cr and Al). To do.
In the present invention employing such a configuration, since the coating layer includes the MCrAlX alloy having wear resistance, the outer peripheral surface of the transport roll becomes difficult to be ground, and the grinding powder generated by the grinding is reduced.

Moreover, the conveyance roll of this invention employ | adopts the structure that a coating layer has ceramics.
In the present invention adopting such a configuration, since the coating layer has ceramics having wear resistance, the outer peripheral surface of the transport roll becomes difficult to be ground, and the grinding powder generated by grinding is reduced.

Moreover, the conveyance roll of this invention employ | adopts the structure that a coating layer has a cermet.
In the present invention employing such a configuration, since the coating layer has a cermet having abrasion resistance, the outer peripheral surface of the transport roll becomes difficult to be ground, and the grinding powder generated by grinding is reduced.

Moreover, the conveyance roll of this invention employ | adopts the structure that the thermal expansion coefficient of a coating layer is substantially the same as the thermal expansion coefficient of a base material.
In the present invention employing such a configuration, since the respective expansion coefficients of the base material and the coating layer when the transport roll is heated are substantially the same, the thermal stress generated between the base material and the coating layer is reduced. .

In addition, the transport roll of the present invention includes an intermediate layer that improves the bondability between the base material and the coating layer, and the material of the intermediate layer is selected based on the bonding characteristics of the base material and the coating layer. To do.
In the present invention employing such a configuration, since the bondability between the base material and the coating layer is improved, peeling of the coating layer from the base material is suppressed.

Moreover, the conveyance roll of this invention employ | adopts the structure that the thermal expansion coefficient of an intermediate | middle layer is substantially the same as the thermal expansion coefficient of a base material and a coating layer.
In the present invention adopting such a configuration, the respective expansion coefficients of the base material, the intermediate layer, and the coating layer when the transport roll is heated are substantially the same. The thermal stress generated between the layer and the coating layer is reduced.

Moreover, the conveyance apparatus of this invention employ | adopts the structure provided with the conveyance roll as described in any one of Claim 1 to 7.
In the present invention employing such a configuration, the outer peripheral surface of the transport roll provided in the transport device becomes difficult to be ground, and the grinding powder generated by grinding is reduced.

Moreover, the hot rolling apparatus of this invention employ | adopts the structure provided with the conveying apparatus of Claim 8.
In this invention which employ | adopts such a structure, the outer peripheral surface of the conveyance roll with which a hot rolling apparatus is equipped becomes difficult to grind, and the grinding powder produced by grinding reduces.

Moreover, the hot rolling apparatus of the present invention includes a heat-retaining furnace that heats the conveyed product and maintains the predetermined temperature, and the conveying apparatus is provided in at least one of the inside and the upstream side of the heat-retaining furnace. Adopt the configuration.
In the present invention employing such a configuration, the transport roll is disposed in an atmosphere maintained at a temperature suitable for the rolling process, and the outer peripheral surface of the transport roll disposed in such an atmosphere becomes difficult to be ground, Grinding powder generated by grinding is reduced.

According to the present invention, the following effects can be obtained.
According to this invention, since the outer peripheral surface of a conveyance roll becomes difficult to be ground, there exists an effect that the conveyance roll can prolong a lifetime and can reduce costs, such as a maintenance and replacement | exchange of a conveyance roll. Moreover, since the grinding | polishing powder which arises by grinding the outer peripheral surface of a conveyance roll reduces, there exists an effect that formation of the buildup in an outer peripheral surface can be suppressed and the quality fall of a conveyed product can be prevented.

1 is a schematic diagram showing an overall configuration of a hot rolling apparatus 1. FIG. FIG. 6 is a schematic diagram illustrating a configuration of a second transport roll 51 or a third transport roll 61. FIG. 10 is a schematic view showing a modification of the second transport roll 51.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The configuration of the hot rolling apparatus 1 according to this embodiment will be described with reference to FIG. FIG. 1 is a schematic diagram showing the overall configuration of the hot rolling apparatus 1.

The hot rolling apparatus 1 according to the present embodiment is an apparatus that manufactures a metal plate or the like from a material such as metal by hot rolling.
As shown in FIG. 1, the hot rolling apparatus 1 includes a heating furnace 2, a front table 3, a roughing mill 4, a rear table 5, a heat-retaining furnace 6, a shearing machine 7, and a finishing mill 8. And a cooling device 9 and a winder 10.

 The heating furnace 2 heats the slab (conveyed material) X containing copper and containing steel as a main component to raise the temperature to a temperature suitable for the rolling process before performing the rolling process in the roughing mill 4 described later. Is.

 The front table 3 is arranged on the downstream side of the heating furnace 2 and conveys the slab X carried out of the heating furnace 2 to the roughing mill 4, and the slab X is repeatedly rolled back and forth in the roughing mill 4. In this case, the slab X is supported from below. The front table 3 includes a plurality of first transport rolls 31 arranged in parallel in the transport direction of the slab X. A driving unit (not shown) that rotates the first transport roll 31 is connected to the first transport roll 31.

 The rough rolling mill 4 has a pair of rotating rolling rolls 41 and 42 and rolling the slab X between the rolling rolls 41 and 42 to form the slab X into a metal plate (conveyed material) Y. Is. The rolling rolls 41 and 42 rotate synchronously in opposite directions, and the rotation direction is freely reversible. Therefore, the rough rolling mill 4 can perform the rolling process repeatedly by reciprocating the slab X.

The rear table (conveying device) 5 is disposed on the downstream side of the roughing mill 4, transports the metal plate Y unloaded from the roughing mill 4 to the heat-retaining furnace 6, and uses the slab X in the roughing mill 4. When slab is reciprocated and repeatedly rolled, the slab X is supported from below. The rear table 5 has a length that prevents the metal plate Y from entering the heat-retaining furnace 6 while the slab X is reciprocated by the roughing mill 4 and formed into the metal plate Y in the conveying direction (for example, 70m).
The rear table 5 includes a plurality of second transport rolls (transport rolls) 51 arranged in parallel in the transport direction of the metal plate Y. The second transport roll 51 is connected to a drive unit (not shown) that rotationally drives the second transport roll 51. Details of the second transport roll 51 will be described later.

A heat-retaining furnace (conveying device, heat-retaining furnace) 6 is a so-called tunnel furnace, which is disposed on the downstream side of the rear surface table 5 and is suitable for a rolling process in a finishing mill 8 described later by heating the metal plate Y. This is for maintaining the metal plate Y at a temperature (for example, about 1100 ° C.). The heat insulating furnace 6 has substantially the same length (for example, about 70 m) as the entire length of the metal plate Y in the transport direction.
The heat-retaining furnace 6 includes a heating burner (not shown) and a plurality of third transport rolls (transport rolls) 61 arranged in parallel in the transport direction of the metal plate Y. The third transport roll 61 is connected to a drive unit (not shown) that rotates the third transport roll 61. Details of the third transport roll 61 will be described later.

The shearing machine 7 is installed on the downstream side of the heat insulating furnace 6 and is for cutting the tip of the metal plate Y carried out from the heat insulating furnace 6.
The finish rolling mill 8 is installed on the downstream side of the shearing machine 7, has a plurality of pairs of rotating rolling rolls 81 and 82, and further rolls the metal plate Y between the rolling rolls 81 and 82, thereby rolling the metal plate The shape of Y is adjusted.

The cooling device 9 is installed on the downstream side of the finishing mill 8, and cools the metal plate Y whose shape is adjusted by the finishing mill 8, and cools the metal plate Y with cooling water.
The winder 10 is installed on the downstream side of the cooling device 9 and winds up the metal plate Y cooled by the cooling device 9.

Next, the structure of the 2nd conveyance roll 51 and the 3rd conveyance roll 61 is demonstrated with reference to FIG. 2A and 2B are schematic views showing the configuration of the second transport roll 51 or the third transport roll 61, wherein FIG. 2A is a side view, and FIG. 2B is an AA thermal sectional view of FIG. Moreover, the arrow U in FIG. 2 shall show an upper direction.
In addition, since the 2nd conveyance roll 51 and the 3rd conveyance roll 61 in this embodiment have the same structure, in the following description, the 2nd conveyance roll 51 is demonstrated and description of the 3rd conveyance roll 61 is abbreviate | omitted. .

The 2nd conveyance roll 51 is for conveying, supporting the metal plate Y from the downward direction. The second transport roll 51 has a base material 52 and a coating layer 53.
The base material 52 is a member formed in a substantially columnar shape, and is formed of a material having heat resistance (for example, a material that can withstand 1100 ° C., which is the internal temperature of the heat-retaining furnace 6). Moreover, the diameter in the both ends 52a of the base material 52 is formed smaller than the diameter in other than that, ie, the center part 52b.

 The covering layer 53 is provided on the outer peripheral surface of the base material 52 and is disposed at a position corresponding to each of both edges in the width direction of the metal plate Y (the axial direction of the second transport roll 51). Further, even when the metal plate Y being conveyed is displaced in the width direction, the metal plate Y has a width that can support both edge portions of the metal plate Y. By providing the covering layer 53, the diameter at the central portion 52 b of the substrate 52 and the diameter at the outer peripheral surface of the covering layer 53 are substantially the same.

Moreover, the coating layer 53 has higher heat resistance and wear resistance than the base material 52, and MCrAlX alloy (where M is at least one of Ni, Co, and Fe, and X is M, Cr). And a metal material such as an element other than Al), ceramics or cermet. The cermet is a composite material of a metal material and ceramics, and examples of the metal material used for the cermet include MCrAlX alloy.
The coating layer 53 is joined to the base material 52 using a thermal spraying process, a welding process, a casting process, or the like. For this joining, a joining method that can withstand the pressure applied from the metal plate Y during conveyance is selected.

 In addition, since the structure of the 3rd conveyance roll 61 is the same as the 2nd conveyance roll 51 as mentioned above, the base material 62 and the coating layer 63 of the 3rd conveyance roll 61 are the base materials 52 of the 2nd conveyance roll 51. And the coating layer 53 has the same configuration.

 Next, the effect | action regarding the coating layer 53 of the 2nd conveyance roll 51 at the time of conveyance of the metal plate Y is demonstrated. In addition, since the effect | action regarding the coating layer 63 of the 3rd conveyance roll 61 is the same as that of the coating layer 53, the description is abbreviate | omitted.

The pressure received by the second transport roll 51 from the metal plate Y during transport is greater than the pressure received from the center in the width direction of the metal plate Y than the pressure received from both edges in the width direction of the metal plate Y. Tend. Therefore, the part facing the said both edge part of the 2nd conveyance roll 51 wears quickly compared with the other part.
But in this embodiment, the coating layer 53 is provided in the location which opposes the said both edge parts of the 2nd conveyance roll 51, and this coating layer 53 has abrasion resistance. Therefore, even if the coating layer 53 is pressed from the metal plate Y, the coating layer 53 is not easily ground.
Therefore, in the present embodiment, wear of the coating layer 53 is suppressed, and costs such as maintenance and replacement of the second transport roll 51 can be reduced.

 Moreover, since the coating layer 53 is not easily ground as described above, generation of grinding powder generated by grinding can be suppressed. Therefore, generation | occurrence | production of the new buildup which arises when this grinding powder adheres to the other part in the outer peripheral surface of the 2nd conveyance roll 51 can be suppressed. Therefore, it is possible to prevent the quality of the metal plate Y from being deteriorated due to the build-up causing a scratch or the like on the surface of the metal plate Y.

 Moreover, the 2nd conveyance roll 51 and the 3rd conveyance roll 61 in this embodiment are each provided in the upstream and the inside of the heat-retaining furnace 6, and those places become high temperature (about 1100 degreeC) all. Yes. Under such a high temperature atmosphere, the grinding generated when the metal plate Y is transported on the transport roll easily adheres to and adheres to other portions of the transport roll. By using the 2nd conveyance roll 51 and the 3rd conveyance roll 61 which concern, generation | occurrence | production of the buildup in the surface can be suppressed actively.

Therefore, according to the present embodiment, the following effects can be obtained.
According to this embodiment, since the outer peripheral surfaces of the second transport roll 51 and the third transport roll 61 are difficult to be ground, costs such as maintenance and replacement of the second transport roll 51 and the third transport roll 61 can be reduced. There is an effect. Moreover, since the grinding | polishing powder produced by grinding the outer peripheral surface of the 2nd conveyance roll 51 and the 3rd conveyance roll 61 reduces, formation of the buildup in the said outer peripheral surface is suppressed, and the quality fall of the metal plate Y is prevented. There is an effect that can be.

 Note that the operation procedures shown in the above-described embodiment, or the shapes and combinations of the components are examples, and can be variously changed based on process conditions, design requirements, and the like without departing from the gist of the present invention. is there.

 For example, in the above embodiment, the second transport roll 51 and the third transport roll 61 are provided with the coating layers 53 and 63 having wear resistance, but either one of the coating layers has wear resistance. May be provided. Further, the first transport roll 31 in the front table 3 may be provided with a coating layer having the same wear resistance as the coating layer 53.

 Further, the second transport roll 51 may include a cooling flow path for cooling the axial center portion of the base material 52. When a cooling fluid such as water or oil flows through the cooling channel, the central portion of the shaft of the base material 52 is cooled, and the life of the bearings of the base material 52 and the second transport roll 51 can be extended. . When the cooling flow path is provided, it is necessary to avoid a decrease in the temperature of the slab X and the metal plate Y, and therefore the outer peripheral surface of the base material 52 and the covering layer 53 are formed of a material having heat insulation properties. It is preferable. The cooling channel may be provided in the first transport roll 31 and the third transport roll 61.

 Further, the thermal expansion coefficient of the covering layer 53 may be substantially the same as the thermal expansion coefficient of the substrate 52. By setting it as such a structure, since each expansion coefficient of the base material 52 and the coating layer 53 when the 2nd conveyance roll 51 is heated becomes substantially the same, it arises between the base material 52 and the coating layer 53. Thermal stress is reduced and peeling of the coating layer 53 is suppressed. Such a configuration may be applied to the third transport roll 61.

Further, an intermediate layer 54 having heat resistance and improving the bondability between the base material 52 and the coating layer 53 may be provided between the base material 52 and the coating layer 53. The configuration of the intermediate layer 54 will be described with reference to FIG. FIG. 3 is a schematic view showing a modification of the second transport roll 51.
As shown in FIG. 3, an intermediate layer 54 is provided between the base material 52 and the covering layer 53. The intermediate layer 54 is selected based on the bonding characteristics between the base material 52 and the coating layer 53 and has the property of improving the bonding properties between the base material 52 and the coating layer 53. By providing such an intermediate layer 54, peeling of the coating layer 53 can be suppressed.
Further, the thermal expansion coefficient of the intermediate layer 54 may be substantially the same as the thermal expansion coefficients of the base material 52 and the covering layer 53. By setting it as such a structure, since each expansion coefficient of the base material 52, the coating layer 53, and the intermediate | middle layer 54 when the 2nd conveyance roll 51 is heated becomes substantially the same, the base material 52, the intermediate | middle layer 54, And the thermal stress generated between the intermediate layer 54 and the covering layer 53 is reduced, and peeling of the covering layer 53 can be suppressed. Note that the above configuration may be applied to the third transport roll 61.

DESCRIPTION OF SYMBOLS 1 ... Hot rolling apparatus, 5 ... Rear surface table (conveyance apparatus), 51 ... Second conveyance roll (conveyance roll), 52 ... Base material, 53 ... Cover layer, 54 ... Intermediate layer, 6 ... Incubator (conveyance apparatus) , Heat retention furnace), 61 ... third transport roll, 62 ... base material, 63 ... coating layer, X ... slab (conveyed object), Y ... metal plate (conveyed object)

Claims (10)

It is a transport roll that is used for transporting transported objects and has a heat resistance and uses a substantially cylindrical base material,
Provided on the outer peripheral surface of the substrate, comprising a coating layer having heat resistance and wear resistance from the substrate,
The transport roll, wherein the coating layer is provided corresponding to both edge portions of the transport object in the axial direction of the transport roll.  The said coating layer has a MCrAlX alloy (However, M is at least 1 sort (s) of Ni, Co, and Fe, X is elements other than M, Cr, and Al). Transport roll.  The transport roll according to claim 1, wherein the coating layer includes ceramics.  The transport roll according to claim 1, wherein the coating layer has a cermet.  The conveyance roll according to any one of claims 1 to 4, wherein a thermal expansion coefficient of the coating layer is substantially the same as a thermal expansion coefficient of the base material. Comprising an intermediate layer that improves the bondability between the substrate and the coating layer;
The material of the said intermediate | middle layer is selected based on the joining characteristic of the said base material and the said coating layer, The conveyance roll as described in any one of Claim 1 to 5 characterized by the above-mentioned.  The conveyance roll according to claim 6, wherein a thermal expansion coefficient of the intermediate layer is substantially the same as a thermal expansion coefficient of the base material and the coating layer.  A transport apparatus comprising the transport roll according to claim 1.  A hot rolling apparatus comprising the transfer device according to claim 8. A heat-retaining furnace for heating the conveyed product and maintaining it at a predetermined temperature;
The hot rolling apparatus according to claim 9, wherein the conveying device is provided in at least one of the inside and the upstream side of the heat-retaining furnace.

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