Temper rolling method for metal strip, temper rolling mill for metal strip, and manufacturing method of metal strip

Abstract

To provide a temper rolling method for a metal strip and related others capable of suppressing formation of an edge mark in a work roll while maintaining proper surface roughness.SOLUTION: There is provided a temper rolling method for a metal strip using a temper rolling mill in which multiple rolling stands are arranged in one direction, each rolling stand including a pair of work rolls arranged vertically and a pair of backup rolls supporting the pair of work rolls. The method includes: a first installation step of installing the work roll having roughness of 1.50-1.90 μm in one of the roll stands; a second installation step of installing the work roll having a crown of 5 / 100 mm or less in the other of the roll stands disposed downstream of the one of the roll stands in the one direction; and a pressure control load setting step of setting a pressure control load of the one of the roll stands to 0.60 to 0.95×10 kN / mm.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a method for temper rolling a metal strip, a temper rolling mill for a metal strip, and a method for manufacturing a metal strip.

Background Art

[0002] Various types of rolling mills have been put into practical use as rolling mills used for cold rolling and temper rolling of metal strips. Examples of such rolling mills include a four-high rolling mill having a pair of work rolls that press a rolling target and a pair of backup rolls that support the work rolls, and a six-high rolling mill having intermediate rolls in addition to the work rolls and backup rolls, which are generally used.

[0003] In such a rolling mill, when a metal strip of the same width is rolled for a long time, the edge portions of the work rolls are unevenly worn due to contact with the metal strip. Such uneven wear of the work roll is also referred to as, for example, an edge mark.

[0004] When rolling a metal strip having a width wider than the length between edge marks using a work roll with edge marks, there is a problem that the edge marks are transferred to the surface of the metal strip, resulting in an inappropriate state of the appearance of the product.

[0005] The roughness of the work roll is directly related to the appearance of the surface of the product. Therefore, the work roll is replaced in a short period from the start of rolling until its surface roughness decreases. The replacement of the work roll is relatively easy and can be done in a short time. Therefore, the influence on the manufacturing ability of the product due to the replacement of the work roll is small.

[0006] By the way, when an edge mark occurs on the work roll, the edge mark is also transferred to the backup roll in contact with the work roll. When the edge mark is transferred to the backup roll, even if the work roll is replaced, the edge mark will be transferred from the backup roll to the work roll. Therefore, when an edge mark is formed on the work roll, it is also necessary to replace the backup roll. Since replacing the backup roll requires a long production line stop, there is a problem that the production capacity decreases.

[0007] Therefore, in order to prevent the edge mark from being transferred to the metal strip, for example, rolling a metal strip with a gradually decreasing width from a wide metal strip is performed. When the rolling of the narrowest metal strip is completed, the work roll is replaced, the backup roll is maintained, or the replacement is carried out. Also, by adjusting the pressure of the dummy material with the dull roll, the edge mark is removed from the work roll.

[0008] However, just using the method of gradually rolling a metal strip with a decreasing width from a wide metal strip has a problem that the productivity decreases when replacing the work roll and the backup roll. Also, when replacing the work roll and the backup roll, an additional process is required due to the occurrence of an unrolled metal strip, resulting in an increase in production cost.

[0009] Also, in the method of adjusting the pressure of the dummy material with the dull roll, there is a problem that the manufacturing cost increases due to the use of the dummy material. Also, when replacing the dull roll, the production line must be decelerated, resulting in a decrease in productivity.

[0010] As a method for improving the above problems, for example, in Patent Document 1, when rolling a metal strip using a multi-roll mill, the edge mark is prevented by rolling while reciprocating the intermediate roll in the roll axis direction.

[0011] In Patent Document 2, a metal strip with a wide width is gradually rolled into a metal strip with a narrow width, and when the rolling of the metal strip with the narrowest width is completed, a high-roughness material is rolled.

[0012] Furthermore, in Patent Document 3, the surface portion of the rolling roll is blasted with shot grains or grit.

Prior Art Documents

Patent Documents

[0013]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0014] However, in the method described in Patent Document 1, when the metal strip is moved in the axial direction of the roll, it becomes difficult to obtain uniform reduction in the width direction of the metal strip, which may affect surface properties such as the shape and roughness of the steel plate.

[0015] In addition, the method described in Patent Document 1 is limited to a six-high rolling mill having an intermediate roll and a shift function for the intermediate roll. For this reason, there is a problem that it cannot be applied to a four-high rolling mill without an intermediate roll. Also, there is a problem that it cannot be applied to a six-high rolling mill without a shift function for the intermediate roll.

[0016] In the method described in Patent Document 2, a high-roughness material is not always available in sufficient quantity. For this reason, when the high-roughness material is insufficient, the number of applicable times is limited, which affects productivity.

[0017] In the method described in Patent Document 3, a blasting device is required. Therefore, when applying it to an existing rolling mill that does not have a blasting device, there are problems of high installation costs and increased maintenance loads.

[0018] The present invention has been made in view of the above problems, and an object thereof is to provide a temper rolling method for a metal strip and the like that can suppress the formation of edge marks on a work roll while maintaining an appropriate surface roughness of the metal strip.

Means for Solving the Problems

[0019] To solve the above problems, the present invention has the following features. [1] A temper rolling method for a metal strip using a temper rolling mill in which a plurality of rolling stands including a pair of work rolls for rolling the metal strip are arranged in one direction, A first installation step of installing the work roll having a roughness of 1.50 to 1.90 μm in one rolling stand; A second installation step of installing the work roll having a crown of 5 / 100 mm or less in another rolling stand arranged downstream of the one rolling stand in the one direction; A pressure setting step of setting the pressure load of the one rolling stand to 0.60 to 0.95 × 10 kN / mm; A temper rolling method for a metal strip, including: [2] A first pressure setting step of setting the pressure load of the one rolling stand to a first set load when the work roll of the one rolling stand is replaced; After the first pressure setting step is performed, a second pressure setting step of setting the pressure load of the one rolling stand to a second set load higher than the first set load, and In the first pressure setting step, the first set load is set to 0.50 to 0.70 × 10 kN / mm. The temper rolling method for a metal strip according to [1]. [3] The second installation step is performed on the rolling stand arranged at the most downstream among the rolling stands arranged in the one direction, and is the method for temper rolling of a metal strip according to [1] or [2]. [4] In the first installation step, the work roll having a higher roughness than the work roll installed in the other rolling stand is installed in the one rolling stand, and is the method for temper rolling of a metal strip according to any one of [1] to [3]. [5] A temper rolling mill for a metal strip in which a plurality of rolling stands each including a pair of work rolls arranged to face each other are arranged in one direction, It has rolling load setting means for setting the rolling pressure load of one of the rolling stands arranged in the one direction to be lower than that of the other rolling stands arranged downstream of the one rolling stand in the one direction, The roughness of the work roll of the one rolling stand is 1.50 to 1.90 μm, A temper rolling mill for a metal strip, wherein the crown of the work roll of the other rolling stand is 5 / 100 mm or less. [6] A method for manufacturing a metal strip using a temper rolling mill in which a plurality of rolling stands each including a pair of work rolls for rolling the metal strip are arranged in one direction, A first installation step of installing the work roll having a roughness of 1.50 to 1.90 μm in one rolling stand, A second installation step of installing the work roll having a crown of 5 / 100 mm or less in the other rolling stand arranged downstream of the one rolling stand in the one direction, A rolling pressure load setting step of setting the rolling pressure load of one of the rolling stands arranged in the one direction to be lower than the rolling pressure load of the other rolling stands arranged downstream of the one rolling stand in the one direction and to be 0.60 to 0.95 × 10 kN / mm, After the first installation step, the second installation step, and the rolling pressure load setting step are executed, a rolling step of rolling the metal strip with the temper rolling mill, A method for manufacturing a metal strip having

Advantages of the Invention

[0020] According to the temper rolling method and the like of the metal strip of the present invention, by having the first installation step, the second installation step, and the roll pressure setting step, it is possible to suppress the formation of edge marks on the work roll while maintaining an appropriate surface roughness of the metal strip.

Brief Description of the Drawings

[0021]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0022] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a temper rolling machine 100 for a metal strip. The temper rolling machine 100 for a metal strip is arranged in equipment for performing continuous temper rolling.

[0023] As shown in FIG. 1, the temper rolling machine 100 for a metal strip has a rolling unit 10 for rolling the metal strip SS and a roll lowering device 20 for adjusting a part of the rolling conditions of the rolling unit 10. The metal strip SS is not particularly limited, and for example, a steel sheet manufactured for cans can be mentioned. In addition, the metal strip SS preferably has a plate width of 650 mm to 1100 mm, for example. If the plate width is 650 mm or more, the generation of edge marks can be suppressed more effectively. If the plate width is 1100 mm or less, the roughness difference in the width direction can be made smaller.

[0024] The rolling section 10 has rolling stands 11a and 11b arranged in a plurality in one direction D1. In this embodiment, one direction D1 is the same as the rolling direction (hereinafter also referred to as the pressure regulating direction) in which the metal strip SS is rolled and conveyed. Also, the number of rolling stands provided is not particularly limited as long as it is plural, but in this embodiment, two rolling stands are provided.

[0025] Each of the rolling stands 11a and 11b includes a pair of work rolls 12a and 12b provided in the vertical direction so as to face each other. The pair of work rolls 12a and 12b are supported by a pair of backup rolls 13a and 13b. The pair of work rolls 12a and 12b are provided with a space in the vertical direction.

[0026] Therefore, the pair of work rolls 12a and 12b contact the metal strip SS and apply rolling reduction by passing the metal strip SS, which is the material to be rolled, between them. Also, the backup rolls 13a and 13b support the pair of work rolls 12a and 12b from above and below, and suppress the deflection of the work rolls 12a and 12b. Note that each of the rolling stands 11a and 11b is not limited to the four-high rolling mill shown in FIG. 1, and may be a six-high rolling mill.

[0027] The roughness of the work rolls 12a and 12b of the rolling stand 11a arranged on the front stage side in one direction D1 is preferably 1.50 to 1.90 μm. The roughness of the work rolls 12a and 12b can be measured as follows, for example, using a contact type surface roughness measuring instrument. On the work roll barrel part, surface roughness meters are installed at a total of three positions at a position 200 mm from the center and both edge parts. Then, the average value of Ra when measured three times at each width position is taken as the average Ra value at each width position. Then, the average Ra values at each width position obtained above are further averaged to obtain the roughness of the work roll. Note that, as the contact type surface roughness measuring instrument, for example, a small surface roughness measuring instrument (SURFTEST SJ-210 series SJ-210 (standard drive·0.75 mN type): manufactured by Mitutoyo Corporation) can be used.

[0028] The roughness of the work rolls 12a and 12b of the rolling stand 11a arranged on the front stage side is preferably higher than the roughness of the work rolls 12a and 12b of the rolling stand 11b arranged on the rear stage side, which is another rolling stand. For example, the roughness of the work rolls 12a and 12b of the rolling stand 11a arranged on the front stage side is preferably 0.75 to 0.85 μm higher than the roughness of the work rolls 12a and 12b of the rolling stand 11b arranged on the rear stage side.

[0029] The roughness of the work rolls 12a and 12b can be set using, for example, the settings used for the surface roughness of the metal strip to be maintained when the metal strip is manufactured using the existing temper rolling mill 100 of the metal strip. As a method for setting the roughness of the work rolls 12a and 12b, the following method can be used.

[0030] In addition, when three or more rolling stands are provided, the work rolls of the rolling stand provided at the foremost stage are preferably set to the above roughness.

[0031] The rolling reduction device 20 adjusts the arrangement interval of the work rolls 12a and 12b of each rolling stand 11a and 11b, that is, the roll gap, so that the rolling load applied to the metal strip SS becomes a predetermined value. Therefore, the metal strip SS is applied with a predetermined rolling reduction adjusted by the rolling reduction device 20 by passing between the work rolls 12a and 12b of each rolling stand 11a and 11b. In addition, the rolling reduction device 20 can individually adjust the roll gap of the work rolls 12a and 12b of each rolling stand 11a and 11b.

[0032] The rolling reduction device 20 sets the rolling pressure load of one rolling stand 11a arranged on the upstream side in one direction D1 to be higher than that of another rolling stand 11b arranged on the rear stage of the one rolling stand 11a in the one direction D1. In other words, the rolling reduction device 20 functions as a rolling load setting means.

[0033] Figure 2 shows the distribution of the pressure regulating load applied to the metal strip. Figure 2(a) shows a mode of rolling the metal strip using a work roll with a higher crown than the work roll shown in Figure 2(b). Figure 2(b) shows a mode of rolling the metal strip using a work roll with a lower crown than the work roll shown in Figure 2(a). In the present embodiment, the crown is described as meaning a so-called convex crown that protrudes outward from the axis of the work roll.

[0034] As shown in Figures 2(a) and (b), in the width direction of the metal strip, the pressure regulating load decreases from the central side toward the end. This tendency is more prominent in the mode shown in Figure 2(a) where the crown of the work roll is higher.

[0035] Figure 3 shows the surface roughness in the width direction of the metal strip. More specifically, Figure 3 shows the surface roughness in the width direction of the metal strip when the load of the rolling stand 11a arranged on the front stage side, the work roll crown, and the load of the rolling stand 11b arranged on the rear stage side are not changed, and the work roll crown of the rolling stand 11b arranged on the rear stage side is changed. As also shown in Figure 3, in the width direction of the metal strip, the surface roughness increases from the central side toward the ends in the width direction, i.e., the operator's cab side and the side opposite to the operator's cab. This tendency is more prominent in the mode where the crown of the work roll of the rolling stand 11b arranged on the rear stage side is higher.

[0036] In the rolling stands 11a and 11b, the crown of the work roll of the rolling stand 11b provided on the rear stage side is set lower than the crown of the work roll of the rolling stand 11a on the front stage side. The rolling stand 11b provided on the rear stage side makes the crown of the work roll 5 / 100 mm or less. By setting the crown of the work roll of the rolling stand 11b on the rear stage side in this way, the pressure regulating load applied to the edge portion of the metal strip SS can be increased, and the roughness in the pressure regulating direction can be made appropriate.

[0037] When three or more rolling stands are provided, the crown of the work roll of the rolling stand provided at the last stage is preferably set to 5 / 100 mm or less. The crown of the work roll can be measured by obtaining the difference in the work roll diameters between the center part and the outermost edge part of the work roll using a caliper gauge.

[0038] Next, a method for manufacturing a metal strip using the temper rolling mill 100 for the metal strip described above will be described. Fig. 4 shows a flow chart for manufacturing a metal strip. As shown in Fig. 4, By installing a work roll having a roughness of 1.50 to 1.90 μm in the rolling stand 11a on the front stage side, a first installation step is executed (step S101).

[0039] Next, by installing the work roll having a crown of 5 / 100 mm or less in the rolling stand 11b arranged on the rear stage side, a second installation step is executed (step S102). Note that either the first installation step of step S101 or the second installation step of step S102 may be performed first, or they may be performed simultaneously.

[0040] Furthermore, the pressure regulating load of the rolling stand 11a on the front stage side is set higher than the pressure regulating load of the rolling stand 11b on the rear stage side. More specifically, after the first installation step of step S101 and the second installation step of step S102 are performed, a first pressure regulating load setting step of setting the pressure regulating load of the rolling stand 11a on the front stage side to a first set load is executed (step S103). The first set load is a load lower than the pressure regulating load of the rolling stand 11b on the rear stage side, which is another rolling stand. Also, the first set load is preferably set to 0.50 to 0.70 × 10 kN / mm.

[0041] After the first installation step of step S101, the second installation step of step S102, and the pressure regulating load setting step of step S103 are executed, a rolling step is executed by rolling the metal strip with the temper rolling mill 100 for the metal strip (step S104).

[0042] When the rolling step of step S104 is executed, it is determined whether or not the first coil of the metal strip being rolled has ended since the execution of the first pressure regulating load setting step of step S103 (step S105). That is, when the coil of the metal strip being rolled is the first coil (step S105: NO), the rolling step of step S104 is continued while maintaining the first set load.

[0043] When the first coil has ended since the execution of the first pressure regulating load setting step (step S105: YES), the pressure regulating load of the rolling stand 11a arranged on the front stage side is set to a second set load higher than the first set load. The second set load is lower than the pressure regulating load of the rolling stand 11b on the rear stage side which is another rolling stand. Also, it is more preferable that the second set load is set to 0.60 to 0.95×10 kN / mm.

[0044] After the second pressure regulating load setting step of step S106 is executed, the rolling step is executed by rolling the metal strip with the temper rolling mill 100 of the metal strip (step S107).

[0045] As described above, according to the method for temper rolling a metal strip of the present invention, etc., it has a first installation step, a second installation step, a first pressure regulating load setting step, and a second pressure regulating load setting step. Thereby, it becomes possible to suppress the formation of edge marks on the work rolls 12a and 12b while maintaining an appropriate surface roughness of the metal strip.

[0046] In addition, in the present embodiment, the mode in which the second pressure regulating load setting step is executed when the first coil has ended since the execution of the first pressure regulating load setting step has been described. However, the second pressure regulating load setting step is not limited to such a mode and may be executed at an arbitrary timing.

Example

[0047] (Test Example 1) A metal strip was manufactured using an existing temper rolling mill for a metal strip. The temper rolling mill used was a four-stage temper rolling mill composed of two rolling stands. Among the two rolling stands, the rolling stand arranged on the upstream side in the pressure regulating direction is described as the front-stage rolling stand, and the rolling stand arranged on the downstream side is described as the rear-stage rolling stand. Table 1 shows the pressure regulating load and the conditions of the work rolls. In the description of Table 1 and the following description, "target" refers to the target value measured by actual measurement. Also, the numerical range described following "target" is the set value, physical property value, etc. set in the machine or the like so that the numerical value of "target" can be obtained.

[0048]

Table 1

[0049] Hereinafter, in the existing temper rolling mill for a metal strip, the conditions before the settings are changed are described as the conventional conditions. The pressure regulating load of the front-stage rolling stand was set with a target of 1.00×10 kN / mm under the conventional conditions. In this test, the pressure regulating load of the front-stage rolling stand was set to 0.80×10 kN / mm.

[0050] When the pressure regulating load is set low, there is a possibility that the roughness of the metal strip may decrease. In order to suppress the decrease in the roughness of the metal strip, the roughness of the work roll of the front-stage rolling stand was set higher than the conventional conditions. The roughness of the work roll of the front-stage rolling stand was determined as follows.

[0051] (Procedure 1) Under the conventional conditions, the transfer rate was defined as the surface roughness on the mill exit side of the first coil of pressure regulation with respect to the roughness of the work roll of the front-stage rolling stand. That is, it was calculated as transfer rate (%) = steel plate roughness (μm) of the first coil of pressure regulation / work roll roughness (μm). The transfer rates in the rolling direction and the width direction of the metal strip were calculated. The roughness of the work roll of the front-stage rolling stand under the conventional conditions was 1.20 to 1.50 μm. (Step 2) If the pressure regulating load and roll conditions of the rolling stand on the rear stage side are not changed from the conventional conditions, it can be assumed that the surface roughness of the metal strip depends on the pressure regulating load of the rolling stand on the front stage side and the roughness of the work roll. Based on this assumption, the correlation coefficient between the pressure regulating load of the rolling stand on the front stage side and the transfer rate was calculated. (Step 3) From the correlation coefficient calculated in (Step 2) and the pressure regulation on the front stage side, the roughness of the work roll was calculated so as to satisfy the surface roughness criteria described later.

[0052] As a result of the above procedure, the roughness of the work roll of the rolling stand on the front stage side was set aiming at 1.70 μm (1.50 to 1.90).

[0053] (Evaluation of the roughness of the metal strip) The surface roughness of the metal strip was evaluated when the metal strip was manufactured under the conditions described in Table 1. The surface roughness of the metal strip was evaluated at three measurement positions in the width direction. The measurement positions of the surface roughness were the edge on the operator's side, the center position, and the edge on the opposite side of the operator's cab. The evaluation of the surface roughness was carried out based on the surface roughness of the metal strip manufactured under the conventional conditions. Criteria were provided for the pressure regulation direction and the width direction for the surface roughness.

[0054] In addition, the roughness difference between the center and the edge of the metal strip was evaluated. Criteria were provided for the pressure regulation direction and the width direction for the roughness difference. Each of these criteria was set based on the actual performance under the conventional conditions. Furthermore, Table 3 shows the results of the evaluation based on the criteria in Table 2. In Table 3, "〇" indicates that the criteria are met, and "×" indicates that the criteria are not met. Also, the pressure regulation distance indicates the total pressure regulation distance from when the work roll is replaced with a new one until the work roll is replaced again.

[0055]

Table 2

[0056]

Table 3

[0057] As shown in Table 3, the surface roughness in the width direction satisfied the standard at all measurement positions. In contrast, the surface roughness in the pressure regulating direction exceeded the standard at a pressure regulating distance of 0 km, that is, in the first coil subjected to temper rolling after the work roll was replaced, and thus did not meet the standard.

[0058] Also, regarding the roughness difference, the roughness difference in the width direction met the standard, but the roughness difference in the pressure regulating direction did not meet the standard as the roughness at the edge was higher than that at the center at a pressure regulating distance of 100 km or less.

[0059] From the above tests, only by setting the pressure regulating load and adjusting the roughness of the work roll, the roughness and roughness difference of the metal strip equivalent to the conventional conditions could not be obtained. In particular, it is considered that the surface roughness at the edge of the metal strip deviated from the standard.

[0060] (Test Example 2: Setting of the Crown of the Work Roll) In response to the results of Test Example 1, the crown of the work roll of the rolling stand on the latter stage side was set. Table 4 shows the pressure regulating load and the conditions of the work roll. Also, the load of the rolling stand on the front stage side was targeted at 0.70×10 kN / mm only for the first coil of pressure regulation, and targeted at 0.80×10 kN / mm from the second coil onwards. The crown of the work roll of the rolling stand on the latter stage side was set to 5 / 100 mm.

[0061] [Table 4]

[0062] The surface roughness and the roughness difference between the center and the edge were evaluated in the same manner as in Test Example 1. The results are shown in Table 5. The evaluation criteria are the same as those in Test Example 1.

[0063] [Table 5]

[0064] In the comparative example of Test Example 1, the surface roughness of the first coil after roll change and the roughness difference in the pressure regulating direction did not meet the criteria. On the other hand, in the example, it was found that these evaluations could also meet the criteria and products with a surface roughness equivalent to the conventional conditions could be manufactured. Also, in the example, not only the surface roughness but also the gloss and color tone were evaluated and confirmed to be equivalent to the conventional conditions.

[0065] (Evaluation of Edge Marks) Also, under the conditions of Test Example 2, a comparison of the edge mark suppression effect with the conventional conditions was carried out. The results of the edge mark suppression effect are shown in Fig. 5. As shown in Fig. 5, in the example, the edge mark generation rate decreased by 73.1% compared to Comparative Example 2 in which the metal strip was manufactured under the conventional conditions.

[0066] Thus, it was found that by adjusting the pressure regulating load of the rolling stand on the front stage side and the roughness of the work roll, and adjusting the crown of the work roll of the rolling stand on the rear stage side, it is possible to suppress the formation of edge marks while maintaining the surface roughness of the metal strip.

Explanation of Signs

[0067] 100 Temper rolling mill for metal strip 11a Rolling stand 11b Rolling stand 12a Work roll 12b Work roll 13a Backup roll 13b Backup roll

Claims

1. A method for temper rolling a metal strip using a temper rolling mill in which a plurality of rolling stands, each including a pair of work rolls for rolling the metal strip, are arranged in one direction, comprising the steps of: A first installation step of installing the work roll having a roughness of 1.50 to 1.90 μm in one rolling stand; a second installation step of installing the work roll having a crown of 5 / 100 mm or less in another rolling stand disposed downstream of the one rolling stand in the one direction; a pressure adjustment load setting step of setting the pressure adjustment load of the one rolling stand to 0.60 to 0.95 × 10 kN / mm; A method for temper rolling a metal strip, comprising:

2. a first pressure adjusting load setting step of setting a pressure adjusting load of the one rolling stand to a first set load when the work roll of the one rolling stand is replaced; and a second pressure adjustment load setting step of setting the pressure adjustment load of the one rolling stand to a second set load higher than the first set load after the first set load setting step is performed.

2. The method for temper rolling a metal strip according to claim 1, wherein in the first pressure adjustment load setting step, the first set load is set to 0.50 to 0.70 × 10 kN / mm.

3. 3. The method for temper rolling a metal strip according to claim 1, wherein the second installation step is performed on a rolling stand arranged at a rearmost stage among the rolling stands arranged in the one direction.

4. 3. The method for temper rolling a metal strip according to claim 1, wherein in the first setting step, the work roll having a roughness higher than that of the work rolls set in the other rolling stand is set in the first rolling stand.

5. 4. The method for temper rolling a metal strip according to claim 3, wherein in the first setting step, the work roll having a roughness higher than that of the work rolls set in the other rolling stand is set in the first rolling stand.

6. A temper rolling mill for a metal strip, comprising a plurality of rolling stands arranged in one direction, each of which includes a pair of work rolls for rolling the metal strip, a rolling load setting means for setting a pressure adjustment load of one of the rolling stands lower than that of another of the rolling stands disposed downstream of the one rolling stand in the one direction; The roughness of the work roll of the first rolling stand is 1.50 to 1.90 μm; a crown of the work roll of said other rolling stand being 5 / 100 mm or less.

7. A method for producing a metal strip using a temper rolling mill in which a plurality of rolling stands, each including a pair of work rolls for rolling the metal strip, are arranged in one direction, comprising: A first installation step of installing the work roll having a roughness of 1.50 to 1.90 μm in one rolling stand; a second installation step of installing the work roll having a crown of 5 / 100 mm or less in another rolling stand disposed downstream of the one rolling stand in the one direction; a pressure adjustment load setting step of setting the pressure adjustment load of the one rolling stand to 0.60 to 0.95 × 10 kN / mm; a rolling step of rolling the metal strip by the temper rolling mill after the first setting step, the second setting step, and the pressure adjustment load setting step are performed; The method for producing a metal strip comprising the steps of:

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