JP2021037542A - Strip steel wire coil manufacturing method - Google Patents

Abstract

To suppress red scale from occurring in a strip steel wire coil which has been tightly wound after rolling and cooling.SOLUTION: A strip steel wire coil 2 is obtained in such a manner that a strip steel wire 1, which has been obtained by continuous rolling on a rolling line 10, is cooled by a cooling line 20, and thereafter, tightly wound in alignment state around a spool 31 of a winding machine 30 which is located on a downstream side of the cooling line. A surface temperature of the strip steel wire 1 at a time of being wound is, for example, 600 to 700°C. Further, by cooling the strip steel wire coil 2 by ventilation means 45 on a transport line 40 to a storage yard 50, a surface temperature of an outer peripheral layer of the strip steel wire coil 2 is made to be 500°C or less. Thus, occurrence of red scale can be suppressed.SELECTED DRAWING: Figure 5

Description

The present invention relates to a method in which a strip steel wire rod obtained by rolling is cooled and then wound tightly to form a strip steel wire rod coil.

A heated billet, bloom, or other steel material is continuously rolled in a rolling line to obtain a strip steel wire rod, and this strip steel wire rod is cooled by a cooling line extending along an extension line of the rolling line on the downstream side of the rolling line, and then cooled. A method of winding a strip steel wire coil by a winding stage arranged on the downstream side of the line is known.

In the method disclosed in Patent Document 1, the strip steel wire rod of about 950 ° C. sent from the final finishing rolling mill of the rolling line is cooled stepwise by sprinkling water with a multi-stage cooling device of the cooling line. After that, it is wound tightly with a winder. The winder is equipped with a spool and an alignment mechanism in front of the spool, and by rotating the spool while aligning the strips with the alignment mechanism, the strips are wound on the spool in multiple layers while applying tension to the strips. take.
Since the strip steel wire rod wound tightly as described above is not bulky, the efficiency of storage and transportation can be improved.

In Patent Document 1, the surface temperature of the strip steel wire rod at the time of winding is set to A1 transformation point or less, for example, 700 ° C. or lower, thereby suppressing the cross-sectional deformation of the strip steel wire rod after winding. Further, in order to avoid lengthening the cooling line, the surface temperature of the strip steel wire at the time of winding is set to, for example, 600 ° C. or higher.

Patent Document 2 discloses a method of cooling a hot coil of rolled steel wire in a storage yard.

JP-A-2018-196903 Japanese Unexamined Patent Publication No. 63-216926

When the strip steel wire is tightly wound and naturally cooled at 600 to 700 ° C. as in Patent Document 1, red scale (Fe ₂ O ₃ ) is generated on the surface of the strip steel wire, which not only spoils the aesthetic appearance but also deteriorates the working environment.
Even in Patent Document 2, red scale is likely to occur on the surface of the strip steel wire.

The present invention has been made to solve the above problems, and a strip steel wire rod obtained by continuous rolling on a rolling line is provided by a cooling line extending along an extension line of the rolling line to the downstream side of the rolling line. After cooling, a strip steel wire coil is obtained by winding tightly on the spool of a winder arranged on the winding stage on the downstream side of the cooling line in an aligned state, and further, a storage yard is obtained from the winding stage. In the transfer line to, the strip steel wire coil is cooled by the cooling means arranged along the transfer line.
According to the above method, by cooling the strip steel wire coil on the transport line, the strip steel wire coil can be cooled at an early stage without being left in a high temperature state, and the generation of red scale can be suppressed.

Preferably, the surface temperature of the strip steel wire rod at the time of winding is 600 to 700 ° C., and the surface temperature of the outer peripheral layer of the strip steel wire rod coil is reduced to 500 ° C. or lower by cooling the strip steel wire rod coil in the transport line. Decrease.
According to the above method, since the winding temperature is equal to or lower than the A1 transformation point, it is possible to suppress the cross-sectional deformation of the strip steel wire even if it is tightly wound. Further, since the temperature is 600 ° C. or higher, it is possible to prevent the cooling line from becoming long. If left in a relatively high winding temperature of 600 to 700 ° C, red scale is likely to occur, but by cooling the surface temperature of the outer layer of the strip steel wire coil to 500 ° C or less in the transport line, the strip steel wire rod The generation of red scale on the surface can be significantly reduced as compared with the case of natural cooling.

More preferably, the surface temperature of the outer peripheral layer is lowered to 400 ° C. or lower by cooling the strip steel wire coil in the transport line.
According to the above method, it is possible to suppress the generation of red scale on the surface of the strip steel wire not only in the outer peripheral layer and the inner peripheral layer of the strip steel wire coil but also in the inside to a level that is difficult to see or close to.

Preferably, the cooling means is composed of a plurality of blower means arranged along the transfer line, and the strip steel wire coil is cooled by the blower.
According to the above method, cooling can be performed while maintaining a good environment on the transport line.

Preferably, the cooling capacity of the cooling means is higher in the upstream portion of the transport line than in the downstream portion.
According to the above method, the surface temperature of the strip steel wire coil can be efficiently lowered.

In another aspect, the cooling means in the upstream portion of the transport line has a device for supplying a cooling medium containing water to the strip steel wire rod coil, and the cooling means in the downstream portion is configured by a blowing means.
According to the above method, since the cooling medium contains water, the cooling capacity on the upstream side of the transport line can be increased. Further, since cooling is performed only by blowing air on the downstream side, moisture does not remain in the strip steel wire coil, and the generation of red rust caused by this moisture can be avoided.

Preferably, the strip steel wire coil is cooled by the blowing means as another cooling means also in the storage yard following the transport line.
According to the above method, when the weight of the bar steel wire coil is heavy and the strip steel wire coil is not sufficiently cooled in the transport line, the occurrence of red scale can be suppressed by cooling the bar steel wire coil in the storage yard. it can. Further, even if the red scale can be suppressed by cooling in the transport line, the storage time from the storage yard to the removal of the bar steel wire wire coil can be shortened by cooling in the storage yard.

According to the present invention, it is possible to suppress the generation of red scale in a strip steel wire coil that is tightly wound after rolling and cooling.

It is a top view which shows the schematic structure of the manufacturing system of the strip steel wire wire coil which concerns on one Embodiment of this invention. It is a top view which shows the schematic structure of the winder of the said manufacturing system. It is a plan sectional view which shows typically the bar steel wire wire coil tightly wound on the spool of the winder. It is an enlarged view which shows the adjacent strip steel wire rod in the strip steel wire rod coil. It is a schematic side view which shows an example of the cooling process of a strip steel wire coil on a transport line. It is a top view of the said transport line. It is a schematic side view which shows another example of the cooling process of a strip steel wire coil on a transport line. It is a schematic side view which shows an example of the cooling process of a strip steel wire coil in a storage yard.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, a manufacturing system for manufacturing a strip steel wire coil is a rolling line 10 arranged linearly along a rolling direction and extending along an extension line of the rolling line 10 on the downstream side of the rolling line 10. It includes a cooling line 20, a winder 30 arranged on a winding stage on the downstream side of the cooling line 20, a transport line 40, and a storage yard 50.

The rolling line 10 includes a heating furnace 11, a rough row rolling mill 12, an intermediate row rolling mill 13, a finishing rolling mill 14, and a final finishing rolling mill 15, which are arranged in order from the upstream side to the downstream side. The billet or bloom heated in the heating furnace 11 is continuously rolled by the rough row rolling mill 12, the intermediate row rolling mill 13, the finishing rolling mill 14, and the final finishing rolling mill 15, and the cross section thereof is gradually reduced in diameter. The strip steel wire rod 1 having a desired size comes out from the final finishing rolling mill 15.

The cooling line 20 is arranged on the exit side (downstream side) of the final finish rolling mill 15 and has a plurality of, for example, seven cooling units 21 to 27 arranged at intervals along the cooling line 20. The strip steel wire rod 1 at about 950 ° C. discharged from the final finishing rolling mill 15 is cooled stepwise by these cooling units 21 to 27 and sent to the winder 30.

The section between the cooling sections 21 to 27 and the section between the cooling section 27 on the most downstream side and the winder 30 provide a reheating section in which the surface temperature of the strip steel wire rod 1 rises due to internal heat.

The cooling process of the strip steel wire rod 1 in the cooling line 20 will be schematically described. Each time the strip steel wire rod 1 passes through the cooling portions 21 to 27, it is sprinkled with water and cooled stepwise. The surface temperature of the strip steel wire rod 1 rises (recovers) due to heat transfer from the central portion in the process of passing through the reheating portion. In this way, the surface temperature of the strip steel wire rod 1 decreases while fluctuating in the cooling line 20.
The temperature of the central portion of the strip steel wire rod 1 gradually decreases. The average temperature of the strip steel wire rod 1 gradually decreases due to the influence of the surface temperature.

In the 7th reheating section on the most downstream side, the surface temperature of the strip steel wire 1 rises sharply immediately after exiting the 7th water cooling section 27, and then continues to rise gradually and averages with the center temperature of the strip steel wire 1. The temperature drops slowly. As a result, when the strip steel wire rod 1 is wound, the difference between the center temperature and the surface temperature is 30 ° C. or less, preferably 10 ° C. or less.

The surface temperature of the strip steel wire rod 1 when it is wound by the spool 31 of the winding machine 30 is preferably 700 ° C. or less. Since it is below the A1 transformation point (727 ° C.), the transformation of the structure from [austenite] to [ferrite + pearlite] is completed at least on the surface when the strip steel wire 1 is wound up. Even if the spool 31 is tightly wound by applying tension, the cross-sectional deformation of the strip steel wire rod 1 can be suppressed.

As described above, the surface temperature of the strip steel wire 1 at the time of winding is 700 ° C. or less, which is lower than that in the case of rolling a general strip steel wire rod, but in the cooling line 20, the water cooling portion on the upstream side has a higher capacity than the downstream side. By cooling and sufficiently reheating and slowly cooling in the water-cooled portion on the downstream side, the lengthening of the cooling line 20 is avoided without transformation into bainite or martensite.

Preferably, the surface temperature of the strip steel wire rod 1 when wound by the spool 31 is set to 600 ° C. or higher. This is because the transformation of the above-mentioned structure is already completely completed at 600 ° C., and cooling from 600 ° C. causes the cooling line 20 to become long.

As shown in FIG. 2, the winder 30 includes a spool 31 whose rotation axis is perpendicular to the rolling direction, and an alignment mechanism 32 arranged immediately before the spool 31. A pinch roller 35 is arranged in front of the alignment mechanism 32. As shown in FIG. 3, the spool 31 has a cylindrical portion 31a, a collar 31b fixed to one end of the cylindrical portion 31a, and a collar 31c detachably attached to the other end.

The spool 31 is rotated by a drive motor (not shown) with the strip steel wire 1 sandwiched between the pinch rollers 35. The rotation of the spool 31 is controlled so that tension acts on the strip steel wire rod 1 between the pinch roller 35 and the spool 31. As the spool 31 rotates, the alignment mechanism 32 reciprocates in the axial direction of the spool 31 to align the strip steel wire rod 1. As a result, the strip steel wire rod 1 is tightly wound in layers as shown in FIG. 3, and the strip steel wire rod coil 2 is obtained.
As shown in FIG. 4, since the strip steel wire rod 1 has a knot 1a on the outer circumference, a gap 2a is formed between the strip steel wire rods 1 in the tightly wound strip steel wire rod coil 2. The porosity of the strip steel wire coil 2 is about 10 to 20%.

Next, in the vicinity of the winder 30, the spool 31 around which the strip steel wire coil 2 is wound as shown in FIG. 3 has one flange 31c removed and the other flange 31b facing down so that the winding shaft is vertical. Take out the strip steel wire coil 2 from the spool 31. The strip steel wire coil 2 taken out is tied with a band or the like to maintain a tightly wound state, and is placed on the transport line 40 with the winding shaft upright. If there is no problem such as deformation of the strip steel wire coil 2, the take-up shaft may be horizontal and placed on the transport line 40.

As shown in FIG. 1, the transport line 40 extends from the winder 30 at right angles to the rolling direction, but the transfer line 40 may extend along the rolling direction. As shown in FIGS. 5 and 6, the transfer line 40 of the present embodiment is composed of a so-called walking beam type transfer device, and includes a large number of transfer machines 41 arranged at intervals along the longitudinal direction thereof. , The elongated support 42 arranged on both sides of the delivery machine 41 is provided. The support base 42 is fixed and does not move.

As shown in FIG. 5, the strip steel wire rod coil 2 is mounted so as to be bridged between the transfer machine 41 closest to the winder 30 and the second transfer machine 41 on the transfer line 40. At the same time, a large number of delivery machines 41 lift the strip steel wire rod coil 2 from the support base 42, move it in the feed direction, then lower it and place it on the support bases 42 on both sides. After that, it moves in the direction opposite to the feed direction of the strip steel wire coil 2 and returns to the original position. By repeating this, the strip steel wire rod coil 2 is conveyed.

In this way, when the strip steel wire coil 2 reaches the end of the transport line 40, a magnetic lift device (not shown) attracts the strip steel wire coil 2 and transports it to the storage yard 50.

As schematically shown in FIG. 5, a plurality of blowers 45 (cooling means; blowing means) are arranged along the transport line 40, and by blowing air from these blowers 45 toward the strip steel wire coil 2, the strip steel is blown. The wire rod coil 2 is cooled. As described above, the strip steel wire coil 2 is tightly wound, but since a gap 2a (see FIG. 4) is formed, at least the exposed surface (outer peripheral surface, inner peripheral surface, top surface) of the strip steel wire coil 2 is blown by air. Air is supplied to the internal strip steel wire 1 from the bottom surface), and the cooled multi-layer strip steel wire 1 further removes heat from the internal strip steel wire 1, so that cooling can be performed efficiently. The blower 45 as a cooling means can be cooled without imposing a load on the working environment of the transport line 40.

As shown in FIG. 5, in the transport line 40, blowers 45 are arranged above and below the strip steel wire coil 2. Since the strip steel wire coil 2 is bridged between the delivery machines 41, the strip steel wire coil 2 can be cooled by blowing air from below. The upper blower 45 may be blown vertically from directly above or horizontally from the side, and there is no limitation on the position and number thereof. By making the blower installation interval narrower on the upstream side and wider on the downstream side so that the cooling capacity on the upstream side of the transport line 40 is higher than that on the downstream side, the strip steel wire coil 2 can be cooled efficiently at an early stage. Can be done.

When the surface temperature of the strip steel wire 1 gradually decreases from 600 to 700 ° C. at the time of winding due to natural cooling, red scale is generated, but the surface temperature of the strip steel wire coil 2 is rapidly increased by the blast cooling in the transport line 40. Since it can be reduced to, the occurrence of red scale can be suppressed.

The strip steel wire rod of the first embodiment D10 (nominal diameter 10 mm) is wound at about 670 ° C. to obtain a 2 ton tightly wound strip steel wire rod coil. This strip steel wire coil has a tubular shape as a whole, and has an outer diameter of 1169 mm, an inner diameter of 900 mm, and a vertical dimension (axial dimension) of 800 mm.
The transport line has a length of 24 m, the walking beam as a transport device is arranged at a feed pitch of 2 m, and the strip steel wire coil is transported to its end in a vertical position over 56 minutes.
Ten lower blowers (cooling means) are arranged along the transport line according to the feed pitch of the walking beam, and the strip steel wire coil is blown from the lower side to cool. In addition, five upper blowers are arranged at intervals along the transport line, and the strip steel wire coil is blown from the upper side to cool the coil. The distance between the upper blowers is narrow on the upstream side of the transport line and wide on the downstream side. The blowing capacity of these blowers is about 500 m ³ / min.

In the above first example, the following experiment was carried out.
(Experiment 1)
The surface temperature of the outer peripheral layer of the strip steel wire coil at the end of the transport line was cooled to 400 ° C. at the highest point. As a result, the red scale could not be visually observed on the surface of the strip steel wire rod located in any of the outer peripheral layer, the inner peripheral layer and the inside of the strip steel wire rod coil.
By the way, when the surface temperature of the outermost layer of the strip steel wire coil is 400 ° C, it is estimated that the surface temperature of the inner peripheral layer of the strip steel wire coil is 480 ° C at the highest point and the internal temperature is 570 ° C at the highest point. Will be done.

(Experiment 2)
When the cooling conditions are relaxed and the temperature of the outer peripheral layer of the strip steel wire coil at the end of the transport line is raised, the amount of red scale generated on the surface of the strip steel wire coil located inside the strip steel wire coil increases. When the surface temperature of the outer peripheral layer of the steel wire coil is cooled to 500 ° C at the highest point, red scale is hardly generated on the surface of the steel wire located in the outer and inner layers of the steel wire coil, but inside. Red scale was observed on the surface of the strip steel wire. However, the occurrence of red scale was significantly less than that of natural cooling, which was an acceptable level.

(Experiment 3)
When the surface temperature of the outer peripheral layer of the strip steel wire coil is cooled to 530 ° C at the highest point (to be 140 ° C lower than the winding temperature), the amount of red scale generated increases, but compared to the case of natural cooling. Was significantly less.

The strip steel wire rod of the second embodiment D10 (nominal diameter 10 mm) is wound at about 670 ° C. to obtain a 1 ton tightly wound strip steel wire rod coil. This strip steel wire coil has a tubular shape as a whole, and has an outer diameter of 1120 mm, an inner diameter of 900 mm, and a vertical dimension (axial dimension) of 500 mm.
The take-up temperature is 670 ° C. as in the first embodiment, and the strip steel wire coil is conveyed to the end of the strip steel wire coil over 26 minutes by the same transfer line.

(Experiment 4)
The surface temperature of the outer peripheral layer of the strip steel wire coil at the end of the transport line was cooled to 430 ° C. at the highest point. As a result, almost no red scale was generated on the surface of the strip steel wire rod located in any of the outer peripheral layer, the inner peripheral layer and the inside of the strip steel wire rod coil.
Since the 1-ton strip steel wire coil of the second embodiment is thinner in the radial direction and has a smaller heat capacity than the 2-ton strip steel wire coil of the first embodiment, the outer peripheral layer is smaller than that of Experiment 1 of the first embodiment. It is considered that the same result was obtained even if the temperature was high.

(Experiment 5)
When the cooling conditions are relaxed and the temperature of the outer peripheral layer of the strip steel wire coil at the end of the transport line is raised, the amount of red scale generated on the surface of the strip steel wire coil located inside the strip steel wire coil increases. When the surface temperature of the outer peripheral layer of the steel wire coil is cooled to 500 ° C at the highest point, red scale is hardly generated on the surface of the steel wire located in the outer and inner layers of the steel wire coil, but inside. Red scale was observed on the surface of the strip steel wire. However, the occurrence of red scale was remarkably less than that of natural cooling, and it was less than that of Experiment 2 of the first example, which was an acceptable level.

(Additional experiment)
When the diameter of the strip steel wire increases to D13 (nominal diameter 13 mm), the cooling effect by blowing air increases even if the weight of the strip steel wire coil is the same. It is considered that this is because the length of the strip steel wire coil is shorter than that of D10, the number of densely wound layers is reduced, and the cooling inside the strip steel wire coil is promoted. Further, when the diameter of the strip steel wire increases to D16 (nominal diameter 16 mm), the cooling effect by blowing air decreases even if the weight of the strip steel wire coil is the same. It is considered that this is because the surface area of the strip steel wire rod with respect to the unit mass is reduced.
As a result, the effect of suppressing the generation of red scale in the strip steel wire is highest in D13, lowest in D16, and intermediate in D10.
The coil was made of 1 ton of strip steel wire, the winding temperature was about 670 ° C., the strip steel wire rods D13 and D16, and the cooling temperature at the transport line was 400 ° C. or less, but the occurrence of red scale was not visible.
When the wire strip coil was 2 tons, the winding temperature was about 670 ° C., the strip steel wire rods D13 and D16, and the cooling temperature at the end of the transport line was 400 ° C. or less, no red scale was visually observed at D13. Even in D16, the occurrence of red scale could not be visually observed in the bar steel wire coil located inside the bar steel wire coil.
When the winding temperature was lower than 670 ° C., the effect of suppressing the generation of red scale was even higher than in the above experiment. When the winding temperature was higher than 670 ° C, the effect of suppressing the generation of red scale was lower than in the above experiment, but the difference was slight up to 700 ° C.

Mechanism of red scale generation The above experimental results will be considered from the viewpoint of the mechanism of red scale generation.
On the surface layer of the strip steel wire coil, Fe ₃ O ₄ and Fe O below it form a layer. In the cooling process, Fe ₃ O ₄ and FeO Young's modulus, due to the difference in thermal expansion coefficient tensile or compressive stress is generated in the boundary surface, Fe ₃ O ₄ layer buckling cracks (surface cracks) occurs. This buckling crack becomes a heterogeneous nucleation site, where Fe ₃ O ₄ is further oxidized, resulting in a red scale (Fe ₂ O ₃ ).

The difference between the linear expansion coefficients of Fe O and Fe _{3 O 4} is about 10% at 500 ° C. or lower, but gradually increases as the temperature rises, and becomes about 20% at 700 ° C. or higher.
The difference between the Young's modulus of Fe O and Fe _{3 O 4} is 15% or less below 550 ° C., but gradually increases as the temperature rises, and becomes about 50% at around 750 ° C.
Therefore, the _{frequency of buckling cracks (foreign nucleation sites) in the Fe 3} O ₄ layer is very low at 500 ° C or lower, suppressed low at 500 to 550 ° C, and gradually increases above 550 ° C. Understandable. The mechanism of red scale generation can be supported by the above experiments 1 to 5.

The weight of the tightly wound strip steel wire coil is generally 1 to 2 tons as described above, but the weight can be increased. In this case, by blast cooling until the surface temperature of the outer peripheral layer of the strip steel wire coil reaches 300 to 350 ° C, the same result as cooling to 400 ° C or less with a 2-ton strip steel wire coil can be obtained. it can.

In the example shown in FIG. 7, the mist (cooling medium containing water and air) is sprayed on the upstream side of the transport line 40 by the mist spraying device 46 (cooling means) to cool the strip steel wire coil 2, and the blower is on the downstream side. It is blown and cooled by 45.
Since water is contained as a cooling medium on the upstream side, the cooling effect can be further improved. Further, since the cooling medium also contains air, it is not rapidly cooled as in the case of simply sprinkling water, and the occurrence of martensitic transformation can be reliably avoided. Since only blast cooling is performed on the downstream side, it is possible to reliably avoid residual moisture and prevent the generation of red rust due to residual moisture. Since other temperature conditions are the same as those in the above-described embodiment, the description thereof will be omitted.

Not limited to the examples of FIGS. 5 and 7, various cooling means can be adopted. For example, more powerful cooling means may be used, especially on the upstream side of the transport line, as long as the martensitic transformation due to quenching can be avoided. For example, instead of the mist spraying device 46, it may be cooled by watering such as a shower, or water may be sprayed intermittently.

When the cooling of the strip steel wire coil 2 is insufficient in the transport line 40, cooling may be continued by the blower 55 (cooling means) in the storage yard 50 as shown in FIG. Even if the transport line 40 can be sufficiently cooled, the waiting time until it is carried out by a truck or the like can be shortened by cooling in the storage yard 50.

The present invention is not limited to the above embodiment, and various embodiments can be adopted. For example, the cooling means may have substantially the same cooling capacity over the entire length of the transport line.
In the transfer line, a conveyor may be used instead of the delivery machine 41 and the support base 42.

The present invention can be applied to a method for manufacturing a bar steel wire coil in which hot-rolled bar steel wire is tightly wound.

1-row steel wire 2-row steel wire coil 10 Rolling line 20 Cooling line 30 Winding machine 31 Spool 32 Alignment mechanism 40 Conveying line 45 Blower (cooling means; blowing means)
46 Sprayer (cooling means)
50 Storage yard 55 Blower (cooling means; ventilation means)

Claims (7)

The strip steel wire rod obtained by continuous rolling on the rolling line is cooled by a cooling line extending along the extension line of the rolling line to the downstream side of the rolling line, and then on the winding stage on the downstream side of the cooling line. A strip steel wire coil is obtained by winding tightly on the spool of the arranged winder in an aligned state.
Further, a method for manufacturing a strip steel wire coil, which comprises cooling the strip steel wire coil by a cooling means arranged along the transport line in the transport line from the winding stage to the storage yard. The surface temperature of the strip steel wire rod at the time of winding is 600 to 700 ° C., and the surface temperature of the outer peripheral layer of the strip steel wire rod coil is lowered to 500 ° C. or less by cooling the strip steel wire rod coil in the transport line. A method for manufacturing a strip steel wire coil, which is characterized by. The method for manufacturing a strip steel wire coil according to claim 2, wherein the surface temperature of the outer peripheral layer is lowered to 400 ° C. or lower by cooling the strip steel wire coil in the transport line. The strip steel wire coil according to any one of claims 1 to 3, wherein the cooling means is composed of a plurality of blower means arranged along the transport line, and the strip steel wire coil is cooled by blowing air. Manufacturing method. The method for manufacturing a strip steel wire coil according to any one of claims 1 to 4, wherein the cooling capacity of the cooling means is higher in the upstream portion of the transport line than in the downstream portion. Claim 1 is characterized in that the cooling means in the upstream portion of the transport line has a device for supplying a cooling medium containing water to the strip steel wire rod coil, and the cooling means in the downstream portion is composed of a blower means. The method for manufacturing a strip steel wire coil according to any one of 3 to 3. The method for manufacturing a strip steel wire coil according to any one of claims 1 to 6, wherein the strip steel wire coil is cooled by a blowing means as another cooling means in the storage yard following the transport line.

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