JP5343957B2 - Strip production equipment and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a facility and a method for manufacturing a strip plate, capable of manufacturing a flat shaped strip plate by easily and quickly correcting, during continuous rolling, the uneven shape of the width end part which occurs in a sheet metal slab with fixed width, and capable of reducing facility cost. <P>SOLUTION: The facility for manufacturing a strip plate includes: a continuous casting machine 6 with a twin-roll or single-roll for continuously casting a molten metal 3 supplied from a tundish 2 arranged at an upper part into a slab 5 with fixed width; and a single-body finishing rolling mill 11 arranged near the downstream side of the continuous casting machine and provided with a pair of upper and lower work rolls 7 and 8 movable in the opposite direction from each other along an axis. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a strip manufacturing facility and a method for manufacturing a strip from a thin slab continuously cast to a constant width by a single finishing mill.

In order to produce a slab having a constant width by a twin roll type continuous casting machine, the slabs are arranged in a horizontal and parallel state with a predetermined amount of gap for forming a slab thickness, and rotate in opposite directions. This is performed by passing a high-temperature casting water between the two rolls (casting rolls). This casting hot water is formed between the side weirs arranged on both end faces of the casting roll and the outer diameter upper part of the casting roll from the opening of the flat nozzle of the tundish arranged just above (upper) the two casting rolls. Is supplied to a cast water reservoir formed by Both side weirs are arranged in a state that matches the slab width to be manufactured and prevents casting water from leaking to the side of the casting roll barrel length having the same length as the slab width. Usually, in a twin roll type continuous casting machine, a slab having a constant width of about 1200 to 2000 mm is manufactured. Further, the twin roll type continuous casting equipment can simplify the apparatus and the equipment arrangement as compared with other continuous casting equipment such as an endless track type continuous casting equipment.
Also, when rolling a slab material made of twin rolls or single rolls with a rolling mill downstream thereof, it is not necessary to use a rolling mill that shifts the roll in the axial direction, using a normal non-shifting rolling mill, As the rolling roll, a conventionally used parabolic or sinusoidal middle, middle and high profile roll (see FIG. 5) is used. The use of the middle, middle and high-profile rolls is widely used in general rolling mills in order to correct the deflection of the rolling rolls.

  However, in a twin roll type continuous casting machine, the casting roll has a long roll body length, so that a heat crown is generated in the casting roll during casting. This heat crown causes a change in casting conditions in each part of the casting roll in the body length direction. In particular, the width ends greatly change. For this reason, the plate thickness distribution in the slab width direction changes as it is closer to both width ends. Furthermore, since the side weirs are arranged on both end surfaces of the roll body length, the heat removal effect is enhanced at the contact surface with the side weirs, and the plate is cooled as the slab width shape is closer to the roll end than the center. The thickness distribution changes and becomes uneven. For example, as shown in FIG. 3A, which will be described later, both end portions are recessed like a drum, and conversely, both end portions protrude like a bee shape as shown in FIG. 4A. In particular, when a thin plate slab having a thickness of 1.2 to 6 mm is manufactured, these uneven shapes are remarkably generated within a range of about 100 mm (= L2 = L3) from the end of the slab. Also, the plate thickness may be nearly double the width end thickness (t4) compared to the vicinity of the center (t3).

  In order to correct the uneven shape generated at the end of the slab as described above by rolling down to a flat shape as described above, a roll crown having a predetermined shape is mechanically ground or heated / cooled on the outer peripheral surface of the roll cylinder as in Patent Document 1 below. In addition, a rolling mill has been proposed in which two upper and lower rolls having the roll crown are complementarily arranged point-symmetrically and moved in the axial direction relative to each other.

JP 4-11281, "Rolling mill"

  The “rolling mill” of Patent Document 1 is a six-high rolling mill having six rolls, and the upper and lower intermediate rolls slide (move) in the same or opposite direction with respect to the width direction of the material to be rolled. It is possible. Further, both intermediate rolls are formed in a convex and concave shape and a roll-shaped curved roll crown over the entire roll body length, and are arranged in a shape that complements each other at a certain relative axial position. In this way, the upper and lower intermediate rolls are formed into bottle-shaped curved contours and can be moved in the axial direction, so that the rolling force in the flat shape can be reduced without reducing the rolling force at the plate edge portion. Manufacture.

However, in the roll-shaped curved crown of the rolling mill of Patent Document 1, the heat crown fluctuation is concentrated within about 100 mm from the end of the slab width when the thin plate slab material is manufactured by the twin roll type casting roll. In the case of a roll crown having a curved contour with a full roll body length, it is difficult to correct the uneven shape generated at the width end, and slip wrinkles occur during rolling. was there.
Further, from the viewpoint of equipment cost for producing a thin rolled material having a thickness of 1.2 to 6 mm, the rolling equipment using a 6-high rolling mill has a problem that causes an increase in cost.
In addition, although there has been a case where a four-high rolling mill is disposed in the vicinity of the downstream side of a conventional twin-roll type or single-roll type continuous casting machine, a four-high rolling mill in which the upper and lower rolling rolls move in the axial direction is arranged. There was nothing.

  The present invention has been developed to solve such problems. That is, an object of the present invention is to easily and quickly correct the uneven shape of the width end portion generated in a thin plate slab having a constant width during continuous rolling to produce a flat strip, thereby reducing the equipment cost. It is to provide a strip manufacturing facility and method.

  According to the present invention, a twin roll or single roll continuous casting machine (6) for continuously casting a slab (5) having a constant width supplied with casting water (3) from a tundish (2) disposed in the upper part, A strip plate comprising: a single finishing mill (11) disposed on the downstream side of the casting machine and having a pair of upper and lower work rolls (7, 8) movable in opposite directions along the axis. Manufacturing equipment is provided.

  Moreover, according to this invention, the continuous casting machine (6) of the twin roll or single roll which is supplied with casting water (3) from the tundish (2) arrange | positioned at the upper part, and continuously casts the slab (5) of fixed width, And a single finishing mill (11) disposed downstream of the continuous casting machine and having a pair of upper and lower work rolls (7, 8) movable in opposite directions along the axis. The flat slab is manufactured by rolling the slab (5) cast and carried out of the continuous casting machine between a pair of upper and lower work rolls movable in opposite directions along the axis of the finishing mill. There is provided a method for manufacturing a strip.

  According to the above-described configuration and method of the present invention, even when an uneven shape is generated at the width end of the thin plate slab due to the heat crown generated in the casting roll during casting in the twin roll or single roll continuous casting machine (6), A single finish rolling mill (four-stage rolling mill), which is arranged downstream of the continuous casting machine and equipped with upper and lower work rolls that can move in the axial direction with each other, giving a rolling reduction of 20 to 30% during continuous rolling Furthermore, straightening rolling for correcting the shape of the slab width end portion can be performed between the upper and lower work rolls. Therefore, a strip having a good flat shape can be manufactured easily and continuously by this straightening rolling. Moreover, since the finishing rolling mill of a single four-stage rolling mill provided with the upper and lower work rolls (7, 8) movable in the axial direction is disposed downstream of the twin roll or single roll continuous casting machine. The rolling line can be shortened and the equipment can be simplified, and the equipment cost can be reduced.

According to a preferred embodiment of the present invention, the upper and lower work rolls (7, 8) incline one side of the roll crown from each inflection point within 200 mm from both ends of the roll cylinder toward the respective roll cylinder ends. A roll crown shape that gradually increases and decreases gradually, and that the other is inclined and the roll crown between both inflection points is a linear or straight outer shape with a center, middle and high profile added. It is arranged point-symmetrically with respect to the rolling center so as to form the opposite side.
Alternatively, as shown in FIG. 6, a grinding crown roll having a shape obtained by adding the shape of the center, middle and high to a straight line between both inflection points is arranged.

  Further, according to a preferred embodiment of the present invention, the upper and lower work rolls (7, 8) are configured so that the roll crown is directed toward each roll cylinder end from each inflection point within 200 mm from both ends of the roll cylinder. Is a grinding crown roll that forms a roll crown between both inflection points in a straight line or a straight line plus the middle, middle, and high profile, and gradually increases and decreases gradually. If the uneven shape occurs at the width end of the slab continuously cast to a certain width, the upper and lower work rolls can be moved to correspond to the uneven shape. A flat strip is produced by moving in a direction opposite to each other by a predetermined amount and correcting and rolling the uneven shape between the roll crowns.

  According to this configuration and method, a plate having a constant width, for example, a wide width of 1500 mm, having a concavo-convex shape generated from a twin-roll or single-roll continuous casting machine concentrated within about 100 mm from the slab width end due to heat crown fluctuation, Even if thin slabs with a thickness of 1.2 to 6 mm are carried into the finishing mill, three types of straight lines corresponding to the uneven shape, or roll crowns with an outer shape obtained by adding the middle, middle, and high shapes to points are formed to be point symmetric The upper and lower work rolls arranged in the upper and lower work rolls can be quickly moved in the axial direction by a predetermined amount and subjected to correction rolling between these roll crowns, so that the shape can be corrected. Furthermore, a rolling reduction of 20 to 30% can be imparted to the thin plate slab between the upper and lower work rolls. Thus, in a single finish rolling mill, rolling reduction to a uniform structure can be achieved by applying a rolling reduction ratio of 20 to 30% to the entire cross-sectional shape of the thin sheet slab together with the straight rolling to the width end portion to the thin sheet slab. In addition, a good strip having a flat and uniform structure can be manufactured continuously from a thin plate slab.

  As described above, according to the strip manufacturing equipment and method of the present invention, a flat strip can be obtained by easily and quickly correcting the uneven shape of the width end portion generated in a thin strip slab having a constant width during continuous rolling. It can be manufactured and has excellent effects such as reduction in equipment cost.

It is a whole lineblock diagram showing the strip manufacture equipment by the present invention. It is an AA arrow line view of FIG. It is a figure which shows the state in which the width | variety edge part of the thin plate slab was dented, and the state of correction rolling. It is a figure which shows the state which the width | variety edge part of the thin plate slab protruded, and the state of correction rolling. It is a figure of the conventional rolling roll. FIG. 3 is a diagram of a grinding crown roll according to the present invention .

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, the same code | symbol is attached | subjected to the common part in each figure, and the overlapping description is abbreviate | omitted.

  FIG. 1 is an overall configuration diagram showing a strip manufacturing facility according to the present invention, FIG. 2 is a view taken along the line AA in FIG. 1, and FIG. 3 is a state in which the width end of the thin plate slab is recessed. FIG. 4 is a diagram illustrating a state of straightening rolling, and FIG. 4 is a diagram illustrating a state in which the width end portion of the thin plate slab is convex and a state of straightening rolling.

  In FIG. 1, a strip manufacturing apparatus 1 according to the present invention is supplied with casting water 3 from a tundish 2 arranged at an upper portion and a slit-shaped nozzle port 4 at a lower portion and continuously casts a thin plate slab 5 having a constant width. A twin-roll continuous casting machine 6 composed of two casting rolls 6a and 6b that are rotated in the direction and arranged in parallel and horizontally with a gap corresponding to the thickness of the sheet, and arranged downstream of the continuous casting machine 6 The thin plate slab 5 to be loaded can be moved in the opposite direction along the axis by a moving device such as a hydraulic cylinder (not shown), and a flat plate is formed by applying a rolling reduction of 20 to 30% during continuous rolling. The upper and lower work rolls 7 and 8 for rolling down the strip 5 'and the upper and lower work rolls 9 and 10 which are held from above and below and do not move in the axial direction are shown in order to prevent the upper and lower work rolls 7 and 8 from being bent. Do not install in the housing. And a kicking single finishing mill 11 Prefecture. Further, the strip 5 ′, which is unloaded from the finishing mill 11 and manufactured into a thin plate having a predetermined flat shape, is placed on a rotatable table roller 12 and conveyed, and is wound through a downstream cutting machine (not shown). It is wound up with a take-up machine. Furthermore, between the continuous casting machine 6 and the finishing mill 11, a rotatable pinch roll 13 for conveying the thin slab 5 is disposed. Note that the thin plate slab 5 having a constant width indicates that the slab plate width L0 is about 1000 to 2000 mm and the plate thickness t0 is about 1.2 to 6 mm.

  In this way, even if the uneven shape occurs in the width end portion of the thin plate slab due to the heat crown generated in the casting roll during casting in the twin roll type continuous casting machine and the heat removal effect from the side weir 14, the continuous casting machine. A single finish rolling mill (four-high rolling mill) that is arranged downstream of the upper and lower and is movable in the axial direction with each other, giving a rolling reduction of 20 to 30%, Straightening rolling for correcting the shape of the slab width end can be performed between work rolls. Therefore, a strip having a good flat shape can be manufactured easily and continuously by this straightening rolling. In addition, since a single four-stage finishing rolling mill equipped with such upper and lower work rolls movable in the axial direction is arranged downstream of the twin roll continuous casting machine, the rolling line is shortened and the equipment is simplified. The equipment cost can be reduced. In this embodiment, the twin roll type continuous casting machine has been described, but it is needless to say that a thin plate slab manufactured by a single roll type can be similarly handled.

Further, in FIG. 2, the upper and lower work rolls 7 and 8 of the four-high rolling mill constituting the single finishing mill 11 and the roll trunk length L0 of the upper and lower holding rolls 9 and 10 are the same as the width of the thin slab 5. have. Further, the outer peripheral surface 16 of the roll cylinder 15 of the upper work roll 7 has an inflection point 17 of the outer diameter D1 and an inflection point 18 of the outer diameter D2 within 200 mm which is a length L1 from both ends of the roll cylinder, respectively. The roll crowns 21 and 22 are gradually increased in an inclined manner toward the roll barrel end portions 19 and 20 having an outer diameter D1 and the other is gradually decreased in an inclined manner, and the roll crown 23 between the inflection points 17 and 18 is linearly formed. It is manufactured with a grinding crown roll formed in a shape. Similarly, the lower work roll 10 having the same length and the same shape as the upper work roll 7 is formed so that the shapes of the three types of roll crowns 21, 22 and 23 that gradually increase and decrease with the upper work roll 7 are oppositely formed. It is arranged point-symmetrically with respect to the rolling center.

In this way, three types of roll crowns are formed which are moved in the axial direction to form a linear shape on the outer peripheral surface of the roll via two inflection points or an outer shape obtained by adding the middle, middle and high shapes to a straight line as shown in FIG. Since the upper and lower work rolls are arranged, a thin slab with a constant width, for example, a wide width of 1500 mm and a plate thickness of 1.2 to 6 mm, is within about 100 mm from the end of the slab width due to heat crown fluctuations. Even if it has a concavo-convex shape and is carried into the finishing mill, the strip shape detector (not shown) placed near the exit side of the finishing mill detects the strip shape and corrects it by straightening according to the shape. be able to. That is, as shown in FIG. 3 (a), the length L2 of both width end portions of the thin plate slab is about 100 mm and is recessed from the thickness t1 to t2, or as shown in FIG. 4 (a), the thin plate slab. Even if the length L3 of both width end portions is about 100 mm and protrudes from the thickness t1 to t3, as shown in FIG. 3B or FIG. It is possible to correct the shape by moving the sheet by a predetermined amount and performing straightening rolling on each roll crown. Furthermore, a rolling reduction of 20 to 30% can be imparted to the thin plate slab between the upper and lower work rolls. Therefore, rolling reduction to a uniform structure can be achieved by applying a rolling reduction ratio of 20 to 30% to the entire cross-sectional shape of the thin sheet slab as well as straight rolling to the width end portion to the thin sheet slab. A good strip having a uniform structure in shape can be produced.

Next, the strip manufacturing method of the present invention will be described with reference to FIG. 2, FIG. 3 and FIG. Appropriate plate having no irregular shape in the vicinity of the plate width of the thin slab 5 cast by the twin-roll continuous casting machine 6 of the above-described strip production facility 1 of the present invention and carried into the single finishing mill 11 If it is a flat shape with a thickness t0, as shown in FIG. 2, the normal 20-30% rolling reduction is applied to the downstream side without moving the work roll in the axial direction between the upper and lower work rolls 7 and 8. The strip 5 'is manufactured and carried out.
Alternatively, the first rolling after casting is performed while winding the strip 5 once in a coil shape with a winding machine (not shown) in the downstream rolling mill and unwinding the coil wound by the rolling mill 11 at a slightly separated place. Sometimes.
On the other hand, when a concave shape is detected in the thin slab 5 as shown in FIG. 3A during rolling by the finish rolling mill 11 within about 100 mm from the end of the slab width due to heat crown fluctuation, as shown in FIG. 3B. The upper work roll 7 is moved to the right side in the figure, and the lower work roll 8 is moved to the left side at the same time in the axial direction, so that the plate thickness t1 and t2 between the three types of roll crowns 21, 22 and 23 arranged symmetrically. Is moved until the distance between the inflection points 17 and 18 of the upper work roll 7 is secured by S1 so that an appropriate sheet thickness t0 is obtained by straightening rolling.
Further, when a convex shape is detected in the thin slab 5 as shown in FIG. 4A during rolling by the finish rolling mill 11 within about 100 mm from the end of the slab width due to heat crown fluctuation, it is shown in FIG. 4B. Thus, the upper work roll 7 is moved to the left side in the figure and the lower work roll 8 is moved to the right side in the axial direction so that the plate thickness t1 between the three types of roll crowns 21, 22 and 23 arranged symmetrically It is moved until the distance between the inflection points 17 and 18 of the upper work roll 7 is secured by S2 so that t3 becomes an appropriate plate thickness t0 by straightening rolling.

  With this strip manufacturing method, even if a sheet slab with a constant width having a concavo-convex shape that is concentrated within about 100 mm from the end of the slab width due to heat crown fluctuations is carried into the finishing mill, it corresponds to the concavo-convex shape. Each of the three types of straight or straight roll crowns with the shape of the middle, middle, and high is formed, and the upper and lower work rolls arranged symmetrically with respect to the point are quickly moved in the axial direction with respect to each other by rapidly moving these roll crowns. The shape can be corrected easily and quickly by applying straightening rolling. Furthermore, since a reduction ratio of 20 to 30% can be imparted to the thin slab at the same time between the upper and lower work rolls, a good strip having a uniform structure with a flat shape can be easily and continuously produced from the thin slab.

  In addition, this invention is not limited to embodiment mentioned above, Of course, it can change variously in the range which does not deviate from the summary of this invention.

DESCRIPTION OF SYMBOLS 1 Strip production equipment 2 Tundish 3 Casting hot water 4 Nozzle port 5 Thin plate slab 5 'Strip 6 Continuous casting machine 6a, 6b Casting roll 7, 8 Vertical work roll 9, 10 Vertical lifting roll 11 Finishing rolling mill 12 Table roller 13 Pinch Roll 14 Side weir 15 Roll cylinder 16 Outer peripheral surface 17, 18 Inflection point 18, 20 Roll cylinder end 21, 22, 23 Roll crown D1, D2 Outer diameter t0, t1, t2, t3 Plate thickness L0 Slab plate width, roll Body length L1, L2, L3 Length S1, S2 Distance

Claims (2)

A twin-roll or single-roll continuous casting machine (6) for continuously casting a slab (5) having a constant width, supplied with casting water (3) from a tundish (2) disposed at the top;
A single finish rolling mill (11) disposed downstream of the continuous casting machine,
The finishing mill has an upper work roll and a lower work roll that are movable in opposite directions along the axis,
Both the upper work roll and the lower work roll are
In the center,
A first end portion having a width of 200 mm or less, which is integrally provided at one end of the central portion, and whose outer diameter gradually decreases in an inclined manner toward the central portion;
A second end portion having a width of 200 mm or less, the outer diameter of which is provided integrally with the other end of the central portion, and gradually increases in an outer diameter toward the central portion.
The central portion is a first point on the outer shape of the upper work roll that becomes a boundary between the central portion and the first end portion, and a boundary between the central portion and the second end portion. It has an outer shape obtained by adding the middle, middle and high shapes to a straight line connecting the second point on the outer shape of the upper work roll,
The said upper work roll and the said lower work roll are the strip production equipment arrange | positioned point-symmetrically with respect to the rolling center so that a roll crown shape may become opposite arbitrarily. A strip manufacturing method for manufacturing a strip using the strip manufacturing equipment according to claim 1,
When an uneven shape is generated at the width end portion of the slab (5) continuously cast to a constant width and carried out of the continuous casting machine, the upper work roll and the lower work roll are placed corresponding to the uneven shape. A strip manufacturing method comprising a step of manufacturing a flat strip by moving the fixed amounts in opposite directions and correcting and rolling the uneven shape between the roll crowns.