JP5353258B2 - Winding method and winding device for high strength thick hot rolled steel sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent loosening of coiling caused by spring back deformation by a method and device for coiling a thick high-strength hot-rolled steel sheet on a mandrel tightly and stably without loosening of coiling. <P>SOLUTION: When coiling the thick high-strength hot-rolled steel sheet from the nose part to the tail end on the mandrel into a coil shape, the hot-rolled steel sheet is coiled by reducing the thickness in the thickness direction with at least one or more wrapper rolls among a plurality of the wrapper rolls which are arranged on the outer periphery of the mandrel. On the coiling device, back up rolls can be provided by making the roll diameters of the wrapper rolls smaller. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a winding method and a winding device for a high-strength thick-walled hot-rolled steel sheet, in particular, a high-strength thick-walled hot-rolled steel sheet that is a material for a high-strength pipe.

  In recent years, the demand for large-diameter, thick-walled, high-strength pipe materials having an API standard of X70 to 100 is increasing mainly for the purpose of improving the transportation efficiency of resources such as crude oil and natural gas in pipelines. In order to efficiently transport these resources, high internal pressure is applied to the inside of the pipe, and characteristics such as high toughness and high strength are also considered for pipe materials in consideration of crustal deformation due to use in cold regions and earthquakes. It has become very important. The pipes used in these pipelines have a large diameter of about 15 to 25 mm and an outer diameter of about 20 inches or more. Conventionally, as a high-strength pipe, a short steel plate that is vertically long in the longitudinal direction An electric sewing tube is often used in which the side is formed into a circular shape, and then the butt portion is welded in the longitudinal direction to form a pipe. Usually, a thick steel plate is manufactured in a substantially rectangular shape by multi-pass rolling in a thick plate mill having one or two hot slabs, and the product length is about 30 m at the maximum. is there.

  On the other hand, in recent years, a thick steel plate is rolled on a hot rolling (hot strip mill) line for thin plate rolling and wound into a coil shape to form a hot-rolled steel plate coil, and then the coil is unwound to a predetermined length. In addition to forming a hot-rolled steel sheet into a longitudinal direction and then forming a hot-rolled steel sheet into a spiral shape at the same time, the spiral steel pipe manufactured into a pipe while welding the butted portion at the end of the plate width is increasing. The hot-rolled steel sheet coil can be manufactured up to about 45 tons. For example, if the thickness is 20 mm and the width is about 1900 mm, the hot-rolled steel sheet has a length of about 151 m, and is formed into a spiral steel pipe having a diameter of 28 inches. The pipe length is about 128m. In this way, by manufacturing the base material before pipe forming with a hot strip mill and making it a hot-rolled steel sheet coil, it is possible to manufacture a continuously long pipe as compared with the case of manufacturing from a thick steel sheet manufactured with a thick plate mill. Can be expected to improve productivity.

  Incidentally, a hot-rolled steel sheet (sometimes referred to as hot strip or simply stripped) 1 after passing through a finishing mill of a hot strip mill in a hot rolling line is usually a winding device (coiler) as shown in FIG. It is wound up by. That is, the front end portion of the hot-rolled steel sheet travels downward by the pinch roll 3 and is guided between the apron 2 and the throat guide 4, and further, a plurality of wrapper rolls 5 (5a to 5d) disposed around the mandrel. ), Are sequentially bent by the three-point support state of the arc-shaped strip guide 6 and the mandrel 7 and wound around the rotating mandrel. Then, the winding proceeds, and finally the hot rolled steel sheet is wound into a coil shape to form a hot rolled coil. When the winding is completed, the mandrel is reduced in diameter so that the coil can be pulled out (for example, Patent Document 1).

JP 2003-80313 A

  In general, when the tip of the hot-rolled steel sheet 1 is wound around a mandrel with a coiler (that is, the tip part is wound), the peripheral speed of the pinch roll 3, the wrapper roll 5, and the mandrel 7 is determined by the conveyance of the hot-rolled steel sheet 1. The speed is controlled to a value with an appropriate lead rate, that is, a speed higher than the conveying speed of the hot-rolled steel sheet 1. The lead rate is cleared at the time when the winding of the tip of the hot-rolled steel sheet 1 is completed, and the lead ratio becomes zero. Thereafter, the mandrel is substantially the same as the conveying speed of the hot-rolled steel sheet 1 (the width due to thermal contraction or tension due to cooling). It is controlled to a peripheral speed synchronized with the effect of excluding shrinkage and the like. The reason why the lead rate is given is to prevent the leading end portion of the hot-rolled steel sheet 1 from becoming loose and undulating and being wound around the mandrel as follows.

  In the coiler, when the leading end of the hot-rolled steel sheet 1 is loosened and is wound in a wavy manner, the subsequent winding cannot be continued or even if it is fortunately wound, When the winding wound up and overlaps outside, the winding becomes thicker, and it becomes a size that protrudes from the housing of the coiler.As a result, it becomes clogged and cannot be pulled out. The damage to each part is great, and it takes many hours to recover.

  In order to prevent such a situation from occurring, when winding the tip of the hot-rolled steel sheet 1 with a coiler, the tip 1a of the hot-rolled steel sheet 1 is used for the purpose of minimizing the looseness of the hot-rolled steel sheet 1. From the start of winding around the mandrel 7 to the completion of winding, the peripheral speed of the pinch roll 3, the wrapper roll 5 and the mandrel 7 is given a lead rate, and the hot rolled steel sheet 1 is wound while being pulled, The loose end of the hot-rolled steel sheet 1 is prevented from being wound and wound around the mandrel.

  The lead rate is determined according to the thickness and hardness (strength) of the hot-rolled steel sheet 1 and is usually a value having a lead rate of 10 to 30% with respect to the conveyance speed of the hot-rolled steel sheet 1, that is, The pinch roll 3, the wrapper roll 5, and the mandrel 7 are controlled to a speed that is 10 to 30% faster than the conveying speed of the hot-rolled steel sheet 1. The lead rate of the mandrel 7 and the wrapper roll 5 is set to be equal to or higher than the lead rate of the pinch roll 3.

After completion of winding of the front end portion of the hot rolled steel sheet 1, the mandrel 7 is substantially synchronized with the conveying speed of the hot rolled steel sheet 1, that is, the conveying speed of the hot rolled steel sheet 1 on the exit side of the final rolling mill of the finish rolling mill. While being rotated, the tension is controlled so as to approach the desired tension with the pinch roll 3 while winding up to the tail end. After the winding of the tip portion is completed, the wrapper rolls 5 a to 5 d are retracted from the coil, and winding is performed without loosening only by the tension between the pinch roll 3 and the mandrel 7.
In addition, although the completion time of winding changes with the intensity | strength of a hot-rolled steel plate etc. so that it may mention later, it is set to the time of a front-end | tip part being wound about 3-5 turns.

  Furthermore, after the winding has progressed and the tail end portion 1b of the hot rolled steel sheet 1 has passed through the pinch roll 3, tension does not act on the hot rolled steel sheet 1. At least one of the wrapper rolls 5a to 5d that has been retracted is pressed against the outer periphery of the coil to suppress loosening of the coil tail end 1b. In addition, when the tail end part of a hot-rolled steel plate comes to about 20 m before a coiler, the conveyance speed (wind-up speed) of a hot-rolled steel plate is decelerated toward the completion | finish of winding.

  And usually, at the end of winding of the hot-rolled coil, after the mandrel is stopped so that the tail end of the hot-rolled steel sheet is located on the lower side of the coil as shown in FIG. The coil carriage that is waiting in the lift is lifted and brought into contact with the cradle roll 8 on the carriage at the tail end of the coil, and the mandrel and the wrapper roll are released after the coil's own weight suppresses the unwinding of the tail end. However, it is extracted from the coiler as it is mounted on the coil carriage. The hot rolled coil extracted from the coiler has one or more strip steel strips at the outermost periphery in a banding device installed adjacent to the coiler in order to prevent unwinding during transportation. The part is fixed in an annular shape.

  However, in the high strength thick hot rolled steel sheet represented by the line pipe material that is particularly targeted in the present invention, since the cross-sectional area of the steel sheet is large and the strength is very high, a tension for winding up tightly is applied. It will be very difficult to do. In general, a high strength material has a very large spring back after bending, and after coil winding is completed, the cradle roll 8 waiting under the coil is raised and pressed against the coil, and then the coil is extracted. Therefore, when the wrapper rolls 5a to 5d are retracted and the mandrel that has been the center of coil rotation is reduced in diameter, the elastic strain component fixed by the mandrel 7 of the coil and the wrapper rolls 5a to 5d is released and a spring back is generated. And winding loosening (winding loosening) of a coil outer peripheral part becomes remarkable.

  Fig. 5 shows an example of the winding shape when winding a coil after winding a high-strength thick material. If the coil is loosely unrolled, it cannot be pulled out from the coiler. Has become prominent and the posture becomes unstable, and after banding, the band is cut off during transportation.

  Thus, although there are many problems in winding up the high-strength thick steel plate, for example, in Patent Document 1, it is difficult to bend the leading edge of the thick steel plate with a pinch roll or a wrapper roll. In order to improve this, the outer diameter of the mandrel is expanded by about 3 turns of the inner winding, the adhesion between the mandrel and the steel plate is improved to prevent slipping, and the coil is wound up. A method for suppressing the deterioration of the shape has been proposed (for example, Patent Document 1).

  When winding a high-strength thick-walled hot-rolled steel sheet in a coil shape by the above-described conventional winding method, the tip can be handled by, for example, the technique disclosed in Patent Document 1, but the tip of the steel sheet Other than the above, especially at the tail end of the strip on the outer periphery side of the coil and in the vicinity thereof, unwinding due to the spring back is likely to occur, and as described above, it becomes easy to cause troubles in handling the coil take-out / conveyance, etc. In a terrible case, when the coil is pulled out from the winding device (coiler) in a state where it is mounted on the coil carriage, the coil is lifted and falls off the carriage.

As described above, in the winding of the strip with a hot-rolled coiler, as shown in FIG. 3, the mandrel is controlled to rotate so that the tail end 1b stops at a position below the coil. The springback deformation of the tail end is suppressed by its own weight, but when winding a high-strength thick steel plate, the springback deformation of the tail end cannot be sufficiently suppressed only by the weight of the coil. Yes.
Thus, in the winding of the high-strength thick-walled hot-rolled steel sheet, the coil tends to become unstable due to unwinding of the outer periphery of the coil until it is extracted from the coiler or transferred to the banding device after that. It was necessary to establish some countermeasure technology.

  Therefore, even in a hot rolling (hot strip mill) line equipped with a strong rolling mill capable of rolling high-strength materials, whether or not winding with a coiler determines whether or not high-strength thick-walled hot-rolled steel sheets can be produced. It is no exaggeration to say that it is.

The present invention has been made in view of the circumstances as described above, and suppresses loosening of the high-strength thick-walled hot-rolled steel sheet in the hot rolling line due to springback, and the winding state is tight and stable. It is an object of the present invention to provide a winding method and a winding device that can perform a specific winding.
In the present invention, the definition of high strength is X65 or more according to API standards, and the thick hot-rolled steel sheet is intended to have a product thickness of 15 mm or more.

The present invention employs the following means in order to solve the above problems.
(1) A method of winding a high-strength thick hot-rolled steel sheet having an API standard of X65 or more and a product thickness of 15 mm or more in a coil shape around a mandrel with a winding device, from the front end of the hot-rolled steel sheet to the tail end When winding up to a portion in a coil shape, the hot rolled steel sheet is wound by at least one of the wrapper rolls arranged on the outer periphery of the mandrel and pressing the hot rolled steel sheet against the mandrel. From the start to the end of the tail, the hot-rolled steel sheet is pressed in the thickness direction to reduce the thickness by applying a compressive force . High strength with API standard of X65 or more and product thickness of 15 mm or more Winding method for thick hot-rolled steel sheet.
(2) the compressive force as the more the yield stress of the heat-rolled steel sheet, characterized in that the thickness reduction of the heat-rolled steel sheet, (1) has been API standards X65 above described, or more high product thickness 15mm Winding method for high strength hot rolled steel sheet.
(3) A winding device used for winding a high-strength, thick-walled hot-rolled steel sheet having an API standard described in (1) or (2) of X65 or more and a product thickness of 15 mm or more, and a mandrel and a mandrel Provided with a plurality of wrapper rolls that press the hot-rolled steel sheet against a mandrel, and at least one of the plurality of wrapper rolls presses in the thickness direction during winding. The hot rolled steel sheet can be reduced in thickness by applying a compressive force, and the at least one wrapper roll has a roll diameter equal to or less than the roll diameter of the other wrapper rolls. Winding device for high strength hot rolled steel sheet.
(4) The at least one or more wrapper rolls include a backup roll. The high-strength thick hot-rolled steel sheet take-up device according to (3).
(5) The at least one or more wrapper rolls having a backup roll are two, and each of the two is disposed at a position facing each other with a mandrel in between (4) Winding device for high-strength thick-walled hot-rolled steel sheet described in 1.

  According to the winding method and the winding device for a high-strength thick-walled hot-rolled steel sheet according to the present invention, the coil is wound on the outer periphery of the mandrel when coiled from the front end to the tail end of the hot-rolled steel sheet. Among the plurality of wrapper rolls, at least one or more wrapper rolls press the hot-rolled steel sheet in the plate thickness direction and reduce the thickness by applying a compressive force. The strength thick hot-rolled steel sheet can be wound tightly and stably, and unwinding due to springback can be suppressed. As a result, it is possible to prevent troubles that occur during handling such as taking out and transporting the coil during winding and after winding.

It is a figure which shows one example of the winding apparatus of the high intensity | strength thick hot-rolled steel plate by this invention. It is a figure which shows another example of the winding apparatus of the high intensity | strength thick hot-rolled steel plate by this invention. It is a figure which shows the coil without unwinding. It is a figure which shows one example of the winding apparatus of the conventional hot-rolled steel plate. It is a figure which shows the coil with winding looseness.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
As a result of intensive studies on a technique for suppressing coil unwinding (winding loosening) due to the spring back of the high-strength thick-walled hot-rolled steel sheet coil, the present inventors have made extensive studies, and as a result, at least one of the plurality of wrapper rolls. The idea was to reduce the thickness by pressing a high-strength thick hot-rolled steel sheet in the thickness direction with two or more wrapper rolls.

  Generally, in bending, tensile stress is applied outside the bend, and compressive stress is applied inside the bend to remove the processing force, that is, in the unloading process, spring back deformation to a position where the bending moment in the plate thickness section becomes zero. Occurs. In order to reduce this springback deformation, it is known that the amount of deformation until the bending moment becomes zero can be reduced by unloading after applying tensile strain or compressive strain in the longitudinal direction after bending. (See, for example, Japan Society for Technology of Plasticity "Bending-Challenge to Higher Accuracy", Corona, January 10, 1995, p. 28).

  In the present invention, this principle is applied to winding of a high-strength thick-walled hot-rolled steel sheet coil. As an external force after bending, it is pressed in the thickness direction with at least one wrapper roll and compressed. Is added to give compression distortion. In winding a hot-rolled steel plate, the plate width is 100 to 1000 times wider than the plate thickness, so that it is almost in a plane strain state, and when compressive force is applied in the plate thickness direction, The deformation is almost zero, and it can be approximated when an elongation strain occurs only in the circumferential direction of the bending. As an additional action, when pressing the hot-rolled steel sheet with the wrapper roll in the plate thickness direction, the inner surface side is a hot-rolled steel plate coil, so the strain during compression in the plate thickness direction is the contact length at the time of reduction. It is large on the short outer peripheral side, that is, on the wrapper roll side, and the circumferential deformation is also larger on the outer peripheral side. That is, the present inventors have found that bending deformation occurs in the same direction as the bending deformation of the coil, which has a great effect on reducing unwinding due to springback.

  In order to reduce the thickness by applying a compressive strain in the thickness direction with the wrapper roll, it is necessary to reduce the thickness with a pressure higher than the yield stress of the material.

  Multiple wrapper rolls arranged on the outer periphery of the mandrel may have the same roll diameter, but the strength of the high-strength thick-walled hot-rolled steel sheet is very high, and the reduction load required for thickness reduction increases. It is desirable to use a wrapper roll having a smaller diameter than the roll diameter of other wrapper rolls that are not reduced in thickness. Further, in order to suppress the bending of the coil of the wrapper roll in the radial direction, it can be supported by a backup roll. When two wrapper rolls for reducing the thickness are provided, it is desirable that these two wrapper rolls are arranged at positions facing each other with a mandrel in between.

  FIG. 1 is a diagram showing an example of a winding device for a high-strength thick-walled hot-rolled steel sheet (hereinafter sometimes simply referred to as “hot-rolled steel sheet”) according to the present invention. In this example, the hot-rolled steel sheet is compressed in the plate thickness direction by the two wrapper rolls 5b, so that the diameter is ½ of the other wrapper rolls 5a, 5c, and 5d. And it is an example which installed the backup roll 9 which supports this roll adjacent to the wrapper roll 5b, and raised the bending rigidity of the wrapper roll. This is because, when compression in the thickness direction is applied to a hot-rolled steel sheet, when the diameter of the wrapper roll 5b is small, that is, when the bending rigidity as the roll is small, the wrapper roll 5b is greatly bent in the radial direction of the coil. This is because effective compressive deformation cannot be imparted to the hot-rolled steel sheet. When the bending rigidity of the wrapper roll 5b is sufficiently large, it is not necessary to provide a backup roll.

Although FIG. 1 shows an example in which the wrapper roll 5b is provided with one backup roll 9, a plurality of backup rolls may be installed at several locations on the outer periphery of the wrapper roll as necessary. Further, in the present invention, since the hot rolled steel sheet is subjected to thickness reduction deformation in the winding device, in order to obtain a desired product thickness, the thickness in the final finishing rolling mill is reduced in the winding device. What is necessary is just to set in consideration of quantity.
In FIG. 1, four wrapper rolls are provided, but usually two to four wrapper rolls are provided. In the present invention, the number of wrapper rolls is not limited to four and may be two or three.

  In the study by the present inventors, it has been confirmed that the thickness reduction of the hot-rolled steel sheet in the winding device is sufficient if it is about 1% of the thickness, and a wrapper for reducing the hot-rolled steel sheet. A method of strengthening or winding up the equipment as necessary, such as performing a predetermined sheet thickness reduction with one roll, or performing a predetermined sheet thickness reduction using a plurality of wrapper rolls for reducing the hot-rolled steel sheet Can be adjusted.

  In addition, since the hot rolled steel sheet is subjected to plate thickness reduction by a wrapper roll, a large lateral load is applied to the mandrel in the axial direction, so it is desirable to increase the rigidity of the mandrel with respect to the lateral load. Moreover, when performing the thickness reduction of a hot-rolled steel sheet with a plurality of wrapper rolls, for example, as shown in FIG. 2 wrapper roll 5b and No. 2 It is desirable to cancel the lateral force with respect to the mandrel shaft by reducing the thickness with a wrapper roll at a position facing each other with a mandrel in between, such as a combination of four wrapper rolls 5d.

Examples of the present invention will be described below.
The target material is API standard X80 grade, and the slab (weight: 33 tons) with a thickness of 250 mm, width of 1850 mm, and length of 9090 mm is subjected to a rough rolling process and a finish rolling process of a hot rolling line to a thickness of 19 to 25 mm. After finishing and cooling to 500 ° C. on a cooling table, it was wound up by a winding device. The winding device is as shown in FIG. The diameter of the two wrapper rolls 5b is φ220 mm, and the diameter of the backup roll 9 is φ440 mm. The other wrapper rolls 5a, 5c, and 5d have a diameter of 440 mm, the outer shape of the mandrel 7 has a diameter of 750 mm, and the outer diameter of the coil wound without loosening as shown in FIG. 3 is 1858 mm.

  The hot-rolled steel sheet speed on the final finish rolling mill exit side, that is, on the cooling table is 150 mpm, and the hot-rolled steel sheet tip 1a enters the coiler at a speed of 150 mpm and starts winding. At this time, the mandrel 7 and the wrapper rolls 5a to 5d are wound at the end of the hot-rolled steel plate 1a at the final finish rolling mill so that winding is started at a predetermined lead rate with respect to the speed of the hot-rolled steel plate 1. Acceleration has begun around the time of passing through. The lead rate of the mandrel 7 at the start of winding was set to 15%, and the lead rates of the wrapper rolls 5a to 5d were set to 25%.

  And after winding start, the deceleration of the mandrel 7 and the wrapper rolls 5a-5d is started, and the speed of the mandrel 7 and the wrapper rolls 5a-5d becomes the sheet passing speed of the hot-rolled steel sheet 1 when the winding is set to 5 rotations. Decelerated to 150 mpm to synchronize. At this time, the wrapper roll 5b having the backup roll 9 is compressed by reducing the thickness of the hot-rolled steel sheet in the thickness direction from the start of winding until the tail end passes, but the wrapper rolls 5a, 5c and 5d are hot-rolled steel sheets. Will not be reduced.

  The tail end 1b of the hot-rolled steel sheet 1 started decelerating from a position about 20 m before the coiler, and the rotation was stopped at a position where the tail end 1b of the hot-rolled steel sheet 1 was on the coil lower side. Then, the cradle roll 8 that has been waiting under the coil is raised and pressed against the lower surface of the coil to fix the vertical position, and then the wrapper rolls 5a to 5d are retracted from the coil, and the mandrel 7 is reduced in diameter for coil extraction. did.

  At this time, depending on the winding condition, coil unwinding may occur due to the springback, and the coil will vibrate up and down and left and right. Analysis was performed. Since the inner circumference of the coil cannot be expanded by the spring back, the shape hardly changes.Therefore, the coil movement is evaluated by defining the maximum amount of vertical movement of the center point of the inner circumference as the coil lift. went. Table 1 shows the results.

Table 1 shows the results. In this table, “○”, “△”, and “X” marks in the “Coil Lift” column indicate the degree of coil lift, where “◯” indicates 3 mm or less, “Δ” indicates 3 mm to 5 mm or less, and “X” indicates 5 mm or more. Respectively. In order to be able to perform handling such as coil removal / conveyance without any trouble, it is desirable that the coil lifting amount is 5 mm or less, preferably 3 mm or less, in a state in which unwinding is reduced.
In the comparative example in Table 1, the conventional winding device shown in FIG. 4 is used, and the diameters of the wrapper rolls 5a to 5d are all 440 mm. On the other hand, in the present invention, the winding device shown in FIG. The thickness reduction is performed by the two wrapper rolls 5b.

In the present invention, the thickness of the side plate is set to the product thickness +0.2 mm in the final finishing rolling mill. The thickness was reduced by 0.2 mm with two wrapper rolls.
According to the present invention, no. 1-No. The coil lifted up by the springback after winding and unloading was as good as 3 mm or less at any plate thickness of 3. On the other hand, in the comparative example in which the thickness reduction amount is 0 mm, No. When the plate thickness is 19.0 mm, the coil lift is within the range of more than 3 mm to 5 mm. 4 and no. In the case of the plate thickness of 25.4 mm and 22.0 mm, the coil floating amount becomes large and exceeds 5 mm.
As described above, it was confirmed that the effect of the present invention, that is, by reducing the thickness by the wrapper roll, the amount of coil lifting can be reduced and the spring back deformation can be reduced.

DESCRIPTION OF SYMBOLS 1 Hot-rolled steel sheet 1a Tip part of hot-rolled steel sheet 1b Tail end part of hot-rolled steel sheet 2 Apron 3 Pinch roll 4 Throat guide 5a 1 wrapper roll 5b No. 2 wrapper roll 5c No. 3 wrapper roll 5d No. 4 Wrapper roll 6 Strip guide 7 Mandrel 8 Cradle roll 9 Backup roll for small diameter wrapper roll 10 Backup roll for small diameter wrapper roll

Claims (5)

It is a method of winding a high-strength thick hot-rolled steel sheet having an API standard of X65 or more and a product thickness of 15 mm or more in a coil shape on a mandrel with a winding device, from the leading end to the tail end When winding in the shape of a coil, it is arranged on the outer periphery of the mandrel, and at least one of the plurality of wrapper rolls pressing the hot rolled steel sheet against the mandrel, immediately after the start of winding of the hot rolled steel sheet The hot-rolled steel sheet is pressed in the thickness direction until the tail end passes, and the thickness is reduced by applying a compressive force. High strength thick heat with API standard of X65 or more and product thickness of 15 mm or more Winding method for rolled steel sheets. The high-strength thick wall having an API standard of X65 or more and a product thickness of 15 mm or more according to claim 1, wherein the compressive force is set to be equal to or greater than the yield stress of the hot-rolled steel sheet. A method for winding hot-rolled steel sheets. A winding device used for winding a high-strength, thick-walled hot-rolled steel sheet having an API standard according to claim 1 of X65 or more and a product thickness of 15 mm or more , which is disposed on the mandrel and the outer periphery of the mandrel. A plurality of wrapper rolls that press the hot-rolled steel sheet against a mandrel, and at least one of the plurality of wrapper rolls is pressed in the thickness direction during winding to apply a compressive force. The high-strength thick-walled hot-rolled steel, wherein the hot-rolled steel sheet can be thinned, and the at least one wrapper roll has a roll diameter equal to or less than the roll diameter of the other wrapper rolls. Steel sheet take-up device.   The winding device for a high-strength thick hot-rolled steel sheet according to claim 3, wherein the at least one wrapper roll includes a backup roll. The at least one or more wrapper rolls having a backup roll are two, and each of the two is disposed at a position facing each other with a mandrel in between. High strength thick-walled hot-rolled steel sheet take-up device.

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