JP6977468B2 - Continuous casting equipment and rolling method - Google Patents

Description

The present invention relates to a continuous casting facility provided with a twin drum type continuous casting device, and a method for rolling slabs in such a facility.

In the twin-drum type continuous casting device, a metal molten metal storage section is formed by a pair of cooling drums for continuous casting (hereinafter, also referred to as "cooling drums") arranged horizontally facing each other and a side dam, and the metal molten metal storage section is formed. A pair of cooling drums is rotated from the stored metal molten metal to cast a thin-walled slab (hereinafter referred to as "casting strip") (for example, Patent Document 1). When the molten metal is stored in the molten metal storage section, the cooling drums are rotated downward from above, and the molten metal is solidified and grown on the peripheral surface of the cooling drum and sent downward as a cast strip. The cast strips delivered from the cooling drum are horizontally fed by pinch rolls and adjusted to the desired plate thickness by a downstream in-line mill. The cast strip whose thickness has been adjusted by the in-line mill is coiled by a winding device installed downstream of the in-line mill.

In such a twin-drum type continuous casting apparatus, the cooling drum is generally at a low temperature before the start of casting, and when the casting is started, the temperature rises due to contact with the molten metal. Further, the cooling drum is cooled from the inner surface by a cooling medium (for example, cooling water) so as not to exceed a predetermined temperature. Hereinafter, the period during which the temperature of the cooling drum reaches a predetermined temperature and becomes constant is defined as the steady casting period, the arbitrary time point of the steady casting period is defined as the steady casting, and the temperature of the cooling drum during the steady casting period is defined as the steady temperature. .. The state of the steady casting period is called the steady state.

The profile of the cooling drum changes over time from the start of casting to the steady state. Therefore, the profile of the cooling drum is set so that the plate profile (plate crown) of the cast strip at the time of steady casting becomes a desired plate profile.

Further, in such a twin drum type continuous casting apparatus, a dummy sheet is used at the start of casting. The tip of this dummy sheet is set in a coil winder, and the tail end of the dummy sheet is set so as to be sandwiched between twin roll drums.

The molten metal at the tip of the cast strip first cools and hardens and binds to the tail end of the dummy sheet described above. After that, the cooling drum rotates and is sequentially supplied to the cast coil. The plate thickness of the joint portion of the dummy sheet is much thicker than the plate thickness of the cast strip. This thick part is also called a hump. If the hump is strongly pressed or rolled with a pinch roll or an in-line mill, meandering or plate breakage will occur. Therefore, this part is passed through, and rolling with an in-line mill is started after the steady state is reached.

The cast strip manufactured by rolling with the above equipment is wound into a coil by a winding device, and then pickled in order to scale the surface. After that, the reverse rolling mill (for example, a cluster rolling mill) is repeatedly rolled to a target plate thickness (for example, 0.3 to 0.2 mm). The roll diameter of the reverse rolling mill has a roll diameter (for example, 60 mm to 80 mm in diameter) smaller than the roll diameter of the in-line mill (for example, 200 mm to 400 mm in diameter).

In rolling with an in-line mill, the cast strip may be deformed in response to changes in the shape of the roll, such as bending and flattening of the roll, which occur during rolling. An example of deformation of a cast strip is an edge drop in which the plate thickness decreases sharply near the end of the cast strip.

Edge drop occurs at the contact surface between the plate end of the cast strip and the roll in contact with the plate end and is caused by the flat deformation of the roll. The flat deformation of the roll is that when the casting strip is rolled, a load is applied to the part where the roll and the casting strip contact, while no load is applied to the part where the roll and the casting strip do not contact. As a result of the large difference in elastic deformation at each location, the roll gap at the end of the plate is smaller than the roll gap at the center of the plate. That is, the flat deformation of the roll is a deformation in which the roll is elastically deformed in a concave shape in the region where the cast strip S and the roll are in contact with each other, and the elastic deformation of the plate end portion is smaller than that of the center of the plate. In the range of edge drop generated by the concave roll deformation, a metal flow is remarkably generated in the roll bite in the plate width direction in the cast strip, and the plate width changes due to a constant mass flow relationship. The range of occurrence of this edge drop or the amount of edge drop varies depending on the roll diameter, and increases as the roll diameter increases.

For example, when rolling is performed using an in-line mill having a roll diameter of 200 mm to 400 mm, edge drops occur in the range of 20 mm to 30 mm from the plate edge. On the other hand, for example, when rolling is performed using a reverse mill having a roll diameter of 60 mm to 80 mm, edge drop occurs 10 mm to 20 mm from the plate edge. As described above, the roll diameter of each rolling mill is different, so that the range of edge drop generation is different. Furthermore, it can be seen that as the roll diameter increases, the range in which edge drops occur increases.

As described above, in the cast strip rolled by a large-diameter roll rolling mill having a relatively large roll diameter, the range of occurrence of edge drop is wide and the amount of edge drop is large. On the other hand, in a cast strip rolled by a small-diameter roll rolling mill having a relatively small roll diameter, the range where edge drops occur is narrow and the amount of edge drops is small. Therefore, when a cast strip rolled by a large-diameter roll rolling mill is rolled by a small-diameter roll rolling mill, at the end of the edge drop generated by the large-diameter roll rolling mill, the plate does not come into contact with the small-diameter roll rolling mill. Alternatively, there is a portion that is not rolled more than the central portion of the plate. The plate portion that does not come into contact with the small-diameter roll or the portion that is not rolled more extremely than the central portion of the plate is less rolled than the plate portion that is in contact with the small diameter roll. Therefore, different portions of the reduction rate, that is, the so-called elongation rate, are generated in the plate width direction. This is called inconsistency under pressure.

Due to this rolling inconsistency, a large tensile stress is generated at the plate end portion rolled with a rolling reduction ratio lower than that at the center of the plate. In particular, when the cast strip has defects (for example, cracks and cracks), tensile stress is concentrated on the defective portion, which causes plate breakage. Therefore, in order to suppress the plate breakage caused by this inconsistency under the pressure and to remove the defect at the plate end portion of the cast strip, a part of the cast strip is trimmed with a constant width from the plate end portion.

The cast strip already rolled by the large-diameter roll rolling mill is trimmed by, for example, about 30 mm on one side (60 mm in total) before rolling by the small-diameter roll rolling mill. This trim significantly suppresses plate breakage due to inconsistency under pressure, but at the same time causes a decrease in yield.

As described above, for example, when a cast strip rolled by an in-line mill having a large diameter roll in a conventional double-drum type continuous casting facility is rolled to a predetermined plate thickness by a reverse rolling mill having a small diameter roll, The manufacturing cost increased due to plate breakage and trimming, and the yield decreased.

As a method for suppressing edge drop that may cause inconsistency under pressure, for example, Patent Document 2 discloses using a single-tapered work roll having a tapered portion on one side of the work roll.

Japanese Unexamined Patent Publication No. 2000-343103 Japanese Unexamined Patent Publication No. 09-206814

However, although rolling with the one-sided taper work roll disclosed in Patent Document 2 is effective as a method for suppressing edge drop, it has the following problems.

When the work roll is tapered as in Patent Document 2, the portion where the work roll and the backup roll are in contact with each other becomes shorter in the roll width direction. Therefore, the Hertz stress on the portion where the work roll and the backup roll are in contact increases, and surface damage such as spalling is likely to occur on the roll. When the work roll is surface-damaged, the damage marks are transferred to the cast strip during rolling, resulting in product failure, or if the work roll is severely damaged, the roll is damaged. As a means for reducing this Hertz stress, for example, it is conceivable to increase the diameter of the backup roll that comes into contact with the work roll. By increasing the diameter of the backup roll, the portion where the work roll and the backup roll are in contact with each other becomes larger in the circumferential direction of the roll, and the Hertz stress is reduced. However, for example, in a rolling equipment having a work roll diameter of 400 mm and a backup roll diameter of 1200 mm, when the backup roll diameter is doubled, the reduction rate of Hertz stress is less than 10%. That is, even if an attempt is made to increase the diameter of the backup roll, the Hertz stress is hardly reduced, and the effect of reducing the surface damage of the roll is small.

Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to break or trim a cast strip manufactured by a twin-drum continuous casting facility by rolling in the next step. It is an object of the present invention to provide a new and improved continuous casting facility and a casting method which can reduce the manufacturing cost and improve the yield by reducing and rolling.

In order to solve the above problems, according to a certain viewpoint of the present invention, a metal molten metal storage portion is formed by a pair of cooling drums and a side dam, and the pair of the cooling drums are rotated and stored in the metal molten metal storage portion. A twin-drum type continuous casting apparatus for casting the molten metal and a rolling apparatus arranged on the downstream side in the casting direction of the twin-drum type continuous casting apparatus for rolling the cast strip are provided, and the rolling apparatus comprises the casting. A quadruple rolling apparatus having a pair of work rolls consisting of an upper work roll and a lower work roll arranged above and below the strip, and a pair of backup rolls consisting of an upper backup roll and a lower backup roll supporting the pair of work rolls. A supply device for supplying a lubricant is provided between the work roll and the backup roll, and the upper work roll and the lower work roll each have one end of the cast strip. A tapered portion whose diameter is reduced from the center to the end in the contacting portion, a first roll diameter portion having the same diameter as the maximum diameter of the tapered portion, and a second roll having the same diameter as the minimum diameter of the tapered portion. The upper work roll and the lower work roll are arranged point-symmetrically with each other, and the profile of the upper backup roll is the profile of the upper work roll among the pair of backup rolls. corresponds to, profile of the lower backup roll, corresponds to the profile of the lower work roll, the supply range of the lubricant of the supply device, the work roll and the effect and the lubricating incremental cost by reducing wear of the backup roll (A) The tapered portion, (b) the tapered portion and the second roll diameter portion, (c) the tapered portion, the second roll diameter portion and the first roll diameter portion. , Ru is set to one of Tei, continuous casting equipment is provided.

Further, in order to solve the above problems, according to another aspect of the present invention, the metal molten metal storage portion is formed by the pair of cooling drums and the side dams, and the metal molten metal storage is stored while rotating the pair of the cooling drums. The rolling apparatus comprises a twin-drum type continuous casting apparatus for casting the molten metal stored in the portion, and a rolling apparatus arranged on the downstream side in the casting direction of the twin-drum type continuous casting apparatus to roll a cast strip. , quadruple to have a pair of backup rolls over consisting backup roll and a lower backup roll for supporting a pair of work rolls and a pair of work rolls made of top work roll and lower work rolls being disposed above and below the cast strip In the rolling apparatus, a supply device for supplying a lubricant is provided between the work roll and the backup roll, and the upper work roll and the lower work roll are each at one end of the cast strip. A tapered portion whose diameter is reduced from the center to the end in a portion in contact with the portion, a first roll diameter portion having the same diameter as the maximum diameter of the tapered portion, and a second having the same diameter as the minimum diameter of the tapered portion. The upper work roll and the lower work roll are arranged point-symmetrically with each other, and among the pair of backup rolls, the profile of the upper backup roll is the upper work roll. Corresponding to the profile of the lower backup roll, the profile of the lower backup roll corresponds to the profile of the lower work roll, and the effect of reducing the wear of the work roll and the backup roll is compared with the increase in the lubrication cost, and the feeding device is used. The supply range of the lubricant is defined as (a) the tapered portion, (b) the tapered portion and the second roll diameter portion, (c) the tapered portion, the second roll diameter portion and the first roll. A rolling method is provided in which the diameter portion is set in order of priority, a lubricant is supplied between the work roll and the backup roll by the supply device, and the cast strip is rolled by the rolling device.

As described above, according to the present invention, according to the present invention, it is possible to reduce plate breakage and trim in the rolling of the next step of the casting strip manufactured by the twin drum type continuous casting apparatus, and it is possible to reduce the manufacturing cost and improve the yield. Can be done.

It is explanatory drawing which shows the schematic structure of the continuous casting equipment which concerns on 1st Embodiment of this invention. It is a figure which shows the shape of the work roll and the backup roll which concerns on 1st Embodiment of this invention. It is a figure which shows the modification of the profile of the work roll and the backup roll which concerns on 1st Embodiment of this invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and the drawings, components having substantially the same functional configuration are designated by the same reference numerals, so that duplicate description will be omitted.

<1. Overview>
The present inventor rolls a cast strip, which is a slab cast by a twin-drum continuous casting machine, by a rolling machine equipped with an in-line mill having a pair of work rolls and a pair of backup rolls supporting the pair of work rolls. In this case, we have been diligently researching rolling technology to reduce plate breakage and trim in the next step of rolling. As a result, we came up with the idea of increasing the contact width between the work roll having the tapered portion and the backup roll in the roll axis direction. In other words, as the shape of the roll, I came up with the idea of imparting a profile corresponding to the roll profile of the work roll having a tapered portion to the backup roll. By increasing the contact width between the work roll and the backup roll, the Hertz stress applied to the work roll having the tapered portion can be reduced, and damage to the work roll can be suppressed.

Also, when the above profile is applied, the backup rolls have different diameters in the roll direction in the width direction. Therefore, if the rotation speeds of the rolls are the same, different roll peripheral speeds are distributed in the width direction of the rolls. That is, even if the peripheral speed of the central portion of the roll is the same, if the peripheral speed of the plate end portion is different, slippage occurs at the peripheral portion of the roll, and the wear of the roll may be accelerated.

Further, at the plate end portion of the cast strip, metal flow in the width direction of the material is likely to occur, and at the plate end portion, the load between the cast strip and the work roll and the stress is higher than that at the center of the plate. Therefore, the work roll in the region in contact with the vicinity of the plate end portion wears faster than the work roll in the region in contact with the vicinity of the plate center portion. As a result, the correspondence between the backup role and the work role in the role profile is further deteriorated.

The present inventor has further obtained the finding that the roll profiles of the backup roll and the work roll do not match due to roll wear, and the shape after rolling changes. From this finding, it was conceived that the wear of the roll was further suppressed by further adding a lubricant in addition to the above-mentioned addition of the profile.

From the above, it is possible to roll while reducing plate breakage and trim in rolling in the next step, improve the yield, and reduce the manufacturing cost. Hereinafter, the present invention will be described in detail.

<2. Outline configuration of continuous casting equipment>
With reference to FIG. 1, a schematic configuration of a continuous casting facility according to the first embodiment of the present invention will be described. For example, the continuous casting equipment includes a tundish (storage device) T, a double drum type continuous casting facility 10, an antioxidant device 20, a cooling device 30, a first pinch roll device 40, and an in-line mill 100. , A second pinch roll device 60 and a take-up device 70.

(Double drum type continuous casting equipment)
As shown in FIG. 1, the twin-drum type continuous casting apparatus 10 includes, for example, a pair of cooling drums 10a and 10b and side weirs (not shown) arranged on both sides of the pair of cooling drums 10a and 10b in the axial direction. ) And. The pair of cooling drums 10a and 10b and the side weir constitute a molten metal storage unit 15 for storing the molten metal supplied from the tundish T.

The pair of cooling drums 10a and 10b includes a first cooling drum 10a and a second cooling drum 10b. The first cooling drum 10a and the second cooling drum 10b have a concave profile with a slightly recessed center in the axial direction. Further, the first cooling drum 10a and the second cooling drum 10b are configured so that the intervals between the cooling drums 10a and 10b can be adjusted according to the plate thickness or the internal quality of the cast strip S to be manufactured. The first cooling drum 10a and the second cooling drum 10b are configured so that a cooling medium (for example, cooling water) can flow inside. The cooling drums 10a and 10b can be cooled by circulating a cooling medium inside the cooling drums 10a and 10b.

In the present embodiment, the first cooling drum 10a and the second cooling drum 10b are set so that, for example, the outer diameter is 800 mm, the drum body length (width) is 1500 mm, and the plate crown of the cast strip S in a steady state is 30 μm (initial). It may be processed). Needless to say, the outer diameters and drum body lengths (widths) of the pair of cooling drums 10a and 10b are not limited to these.

In the twin-drum type continuous casting apparatus 10, a dummy sheet (not shown) is connected to the tip of the casting strip S to start casting. A dummy bar (not shown) having a thickness thicker than that of the cast strip S is provided at the tip of the dummy sheet, and the dummy sheet is guided by the dummy bar (not shown). Further, a hump (not shown) thicker than the plate thickness of the casting strip S is formed at the connection portion between the tip of the casting strip S and the dummy sheet. In rolling in the in-line mill 100, a rolling start method called a flying touch is performed, in which the hump passes through the in-line mill 100 and then starts rolling. By such a rolling start method, the casting strip S from the tip end portion of the casting strip S to the flying touch start portion remains in the cast state.

(Antioxidant device)
The antioxidant device 20 is a device that performs a process for preventing the surface of the casting strip S immediately after casting from being oxidized to generate scale. In the antioxidant device 20, for example, the amount of oxygen can be adjusted by nitrogen gas. The antioxidant device 20 is preferably applied as necessary in consideration of the steel type of the casting strip S to be cast.

(Cooling system)
The cooling device 30 is a device for cooling the cast strip S whose surface has been subjected to the antioxidant treatment by the antioxidant device 20. The cooling device 30 is provided with, for example, a plurality of spray nozzles (not shown), and the cooling water is ejected from the spray nozzles to the surface (upper surface and lower surface) of the casting strip S according to the steel type to form the casting strip S. Cooling.

A pair of feed rolls 87 may be arranged between the antioxidant device 20 and the cooling device 30. The pair of feed rolls 87 sandwich the casting strip S by a reduction device (not shown), and measure the loop length of the casting strip S between the pair of cooling drums 10a and 10b and the feed roll 87. A horizontal transport force is applied to the casting strip S so that the loop length becomes constant. The feed roll 87 is composed of, for example, a pair of rolls having a roll diameter of 200 mm and a roll body length (width) of 2000 mm.

(First pinch roll device)
The first pinch roll device 40 is a pinch roll device arranged on the entry side of the inline mill 100. The first pinch roll device 40 is not shown except for the upper pinch roll 40a and the lower pinch roll 40b, the housing, the roll chock, the rolling load detecting device, and the rolling device (other than the first pinch roll device 40). ) And. The upper pinch roll 40a and the lower pinch roll 40b each have a hollow flow path formed therein, and are configured so that a cooling medium (for example, cooling water) can flow. By circulating the cooling medium, the first pinch roll device 40 can be cooled.

The upper pinch roll 40a and the lower pinch roll 40b may have, for example, a roll diameter of 400 mm and a roll body length (width) of 2000 mm. The upper pinch roll 40a and the lower pinch roll 40b are arranged via a roll chock in the housing and are rotationally driven by a motor (not shown). Further, the upper pinch roll 40a is connected to a taper line adjusting device (not shown) via an upper rolling load detecting device (not shown), and the lower pinch roll 40b is connected to a rolling device (not shown). .) Is connected.

In the first pinch roll device 40 having such a configuration, when the lower pinch roll 40b is pushed up toward the upper pinch roll 40a by the reduction device, the reduction load applied to the upper pinch roll 40a and the lower pinch roll 40b is detected. , Tension is generated in the casting strip S between the first pinch roll device 40 and the straightening device (not shown). Further, the casting strip S in the pair of pinch rolls 40a and 40b and the inline mill 100 so that the tension generated in the casting strip S between the first pinch roll device 40 and the inline mill 100 becomes a preset tension. The moving speed of is controlled. Further, the tension of the casting strip S between the first pinch roll device 40 and the straightening device (not shown) is detected by the tension roll 88a. A position detecting device 41 for detecting the position of the casting strip S may be provided on the upstream side of the first pinch roll 40 device.

(Inline mill)
The in-line mill 100 is a rolling apparatus that rolls the casting strip S to make the casting strip S a desired plate thickness. In the present embodiment, the in-line mill 100 is configured as a quadruple rolling apparatus. That is, the in-line mill 100 includes a pair of work rolls 101a and 101b and backup rolls 102a and 102b arranged above and below the work rolls 101a and 101b.

The work rolls 101a and 101b are arranged with the roll axes parallel to each other. The backup rolls 102a and 102b support the work rolls 101a and 101b and are arranged with the roll axes parallel to each other like the work rolls 101a and 101b. The cast strip S is rolled by such a quadruple rolling apparatus having the work rolls 101a and 101b and the backup rolls 102a and 102b. Hereinafter, the rolls located above the casting strip S when the casting strip S is used as a reference in the arrangement direction of the work rolls 101a and 101b and the backup rolls 102a and 102b are referred to as the upper work roll 101a and the upper backup roll 102a, respectively. The rolls located on the lower side of the casting strip S are referred to as a lower work roll 101b and a lower backup roll 102b, respectively.

The casting strip S to be rolled by the quadruple rolling apparatus having the in-line mill 100 according to the present embodiment is a slab cast by the twin drum type continuous casting apparatus 10. Since the plate width of the casting strip S is determined by the cooling drums 10a and 10b of the twin drum type continuous casting apparatus 10, the plate width of the casting strip S rolled by the inline mill 100 according to the present embodiment is constant. Therefore, the edge drop generation range and the edge drop amount of the work rolls 101a and 101b hardly change for each casting strip S rolled by the in-line mill 100. Therefore, it is not necessary to provide the in-line mill 100 according to the present embodiment with a shift mechanism for shifting the work rolls 101a and 101b.

Further, the in-line mill 100 includes an in-line mill control device for controlling the in-line mill, a plate thickness gauge (neither of them is shown), and the like. The work rolls 101a and 101b are rotationally driven by a motor (not shown) and are cooled by cooling water from the entry side and the exit side. Further, above the backup roll 102a, a hydraulic cylinder (not shown) that presses the backup roll 102a downward is provided.

In the in-line mill 100, after the tip of the casting strip S cast during steady casting passes through the in-line mill 100, the work rolls 101a and 101b of the in-line mill 100 are rotated to tighten the roll gap and start rolling. Is being done.

The inline mill 100 is controlled by an inline mill control device (not shown). The in-line mill control device includes, for example, a mill control unit that controls the in-line mill 100 collectively, a hydraulic cylinder control unit that controls a hydraulic cylinder, a roll rotation control unit, a roll bending force setting unit, and the like (none of them are shown). including.

The hydraulic cylinder control unit reduces and controls the hydraulic cylinder connected to the backup roll 102a. The hydraulic cylinder control unit controls the hydraulic cylinder based on an instruction from the mill control unit (not shown) that controls the inline mill 100 in a centralized manner, and adjusts the roll gap between the work rolls 101a and 101b. At this time, the mill control unit is a plate in which the casting strip S is preset based on the plate thickness of the casting strip S measured by a plate thickness gauge (not shown) installed on the outlet side of the inline mill 100. Adjust the roll gap so that it is formed thicker. As the plate thickness gauge, for example, an X-ray plate thickness gauge or the like may be used. The roll rotation control unit (not shown) controls the rotation speeds of the work rolls 101a and 101b based on the instruction from the mill control unit (not shown). The roll bending setting unit sets the roll bending force for the work rolls 101a and 101b.

(Second pinch roll device)
The second pinch roll device 60 is arranged on the exit side of the inline mill 100. Similar to the first pinch roll device 40, the second pinch roll device 60 includes an upper pinch roll, a lower pinch roll, a rolling load detecting device, and a rolling device (all except for the second pinch roll 60). It has.) And. The upper pinch roll and the lower pinch roll each have a hollow flow path formed therein, and are configured so that a cooling medium (for example, cooling water) can flow. The pinch roll can be cooled by circulating the cooling medium. The upper pinch roll and the lower pinch roll may have, for example, a roll diameter of 400 mm and a roll body length (width) of 2000 mm. Further, the upper pinch roll and the lower pinch roll are arranged via a roll chock in the housing, and are rotationally driven by a motor (not shown). A tension roll 88b is arranged between the in-line mill 100 and the second pinch roll device 60.

(Winling device)
The take-up device 70 is a device arranged on the outlet side of the second pinch roll device 60 and takes up the cast strip S in a coil shape. A deflector roll 89 is arranged between the second pinch roll device 60 and the take-up device 70.

The outline configuration of the continuous casting facility has been described above.

<3. Inline mill details>
The work rolls 101a and 101b and the backup rolls 102a and 102b of the inline mill 100 according to the present embodiment are set with a predetermined roll profile in order to suppress edge drop generated in the casting strip S. Hereinafter, based on FIGS. 2 and 3, the roll profiles of the work rolls 101a and 101b and the backup rolls 102a and 102b of the inline mill 100 according to the present embodiment and their actions will be described. Note that FIG. 2 is an explanatory diagram showing the shapes of the work rolls 101a and 101b and the backup rolls 102a and 102b of the inline mill 100 according to the present embodiment. FIG. 3 is an explanatory diagram showing a modified example of the profile of the work roll and the backup roll according to the present embodiment.

In this embodiment, the cast strip S will be described separately as a plate end portion Se and a plate center portion Sc as follows. The plate end portion Se is a region in the vicinity of the plate edge including the plate edge, and includes at least a portion where edge drop occurs. The plate center sc is a region other than the plate end Se, including the plate center.

[3.1. Roll profile]
In the in-line mill 100 according to the present embodiment, at least one of the upper work roll and the lower work roll shrinks from the center toward the end in the portion where the plate end Se on one side of the casting strip S contacts. It has a tapered portion with a diameter, and at least one of the upper work roll and the lower work roll has a tapered portion whose diameter is reduced from the center toward the end in the portion where the plate end portion Se on the other side is in contact. Have. At this time, the roll profile of the upper backup roll corresponds to the profile of the upper work roll, and the roll profile of the lower backup roll corresponds to the roll profile of the lower work roll. Hereinafter, examples of role profiles for work rolls and backup roles will be specifically described.

(Taper work rolls on both sides)
First, FIG. 2 shows an example in which tapered portions are provided at both ends of the upper work roll 101a and the upper backup roll 102a. As shown in FIG. 2, the upper work roll 101a has a first roll diameter portion W1 and a first roll diameter portion W1 in the center portion of the roll, respectively, from the center of the roll toward the ends of both rolls in the roll axis direction. It is composed of a tapered portion W2 having a continuous outer peripheral surface and gradually reducing the roll diameter, and a second roll diameter portion W3 in which the tapered portion W2 and the outer peripheral surface are continuous and have the minimum diameter of the tapered portion W2. The roll diameter of the first roll diameter portion W1 is equal to the maximum diameter of the tapered portion W2. The tapered portions W2 formed on one side (left side of FIG. 2) and the other side (right side of FIG. 2) of the upper work roll 101a have the same gradient θ. Therefore, the upper work roll 101a has a profile that is symmetrical in the roll axis direction with respect to the roll center. The gradient θ refers to the angle between the straight line of the roll axis and the tapered portion in the cross section including the roll axis or the projection plane.

Similarly, the upper backup roll 102a has an outer peripheral surface continuous with the first roll diameter portion B1 and the first roll diameter portion B1 of the roll center portion, respectively, from the roll center toward both roll ends in the roll axis direction. It is composed of a tapered portion B2 having a roll diameter gradually increasing, and a second roll diameter portion B3 having a taper portion B2 and an outer peripheral surface continuous with each other and having the maximum diameter of the tapered portion B2. The roll diameter of the first roll diameter portion B1 is equal to the minimum diameter of the taper portion B2.

As shown in FIG. 2, the upper work roll 101a and the upper backup roll 102a have profiles corresponding to each other. Specifically, the first roll diameter portion W1, the taper portion W2, and the second roll diameter portion W3 of the upper work roll 101a are the first roll diameter portion B1, the taper portion B2, and the second roll, respectively. Corresponds to the roll diameter portion B3. With this configuration, the area in contact between the upper work roll 101a and the upper backup roll 102a becomes large, so that the increase in Hertz stress at the portion where the upper work roll 101a and the upper backup roll 102a are in contact is suppressed, and the upper work roll 101a and the upper backup roll 102a are in contact with each other. The surface damage of the roll 102a can be suppressed.

Here, the tapered portion W2 of the upper work roll 101a (hereinafter, also simply referred to as a tapered portion W2) is provided at least at a position including a portion in contact with the plate end portions Se on both sides of the cast strip S. With this configuration, the plate end portion Se of the cast strip S is rolled by the tapered portion W2 at which the upper work roll 101a is reduced in diameter, and the flat deformation of the upper work roll 101a is suppressed. Thereby, the occurrence of edge drop of the cast strip S can be suppressed. At this time, the plate end portions Se on both sides of the cast strip S may be located between the start point where the tapered portion W2 starts to reduce the diameter and the roll end of the upper work roll 101a, respectively, and the tapered portion W2 has the reduced diameter. It may be located between the start point where the taper portion W2 starts and the end point where the taper portion W2 finishes the diameter reduction. Further, the starting point at which the tapered portion W2 starts to reduce the diameter may be the boundary between the plate center portion Sc and the plate end portion Se.

The tapered portion W2 may have an end point at which the diameter reduction is completed from the center of the roll toward the end of the roll to be the end of the roll of the upper work roll 101a. In this case, the second roll diameter portion W3 does not exist. By reducing the gradient θ of the tapered portion W2, the possibility of edge-up occurring can be suppressed as described later. Further, by eliminating the second roll diameter portion W3, it becomes easy to process the roll and to correspond the profile between the backup roll and the work roll.

The tapered portion B2 of the upper backup roll 102a is provided with a profile corresponding to the profile of the tapered portion W2 described above.

As shown in FIG. 2, the lower work roll 101b may be a flat roll having the same roll diameter in the roll width direction. The lower backup roll 102b also has the same roll diameter in the roll width direction. The lower work roll 101b and the lower backup roll 102b have corresponding profiles.

(One side taper work roll)
Next, FIG. 3 shows an example in which a tapered portion is provided to one end of the upper work roll 201a and the lower work roll 201b, respectively. That is, in the example shown in FIG. 3, either the upper work roll 201a or the lower work roll 201b has a tapered portion w2 at a position in contact with the plate end portion Se on one side of the casting strip S. The upper work roll 201a and the lower work roll 201b are arranged point-symmetrically so that the tapered portion w2 of the upper work roll 201a and the tapered portion w2 of the lower work roll 201b are in contact with different plate end portions Se of the cast strip S, respectively. .. The point-symmetrical arrangement allows the upper work roll 201a and the lower work roll 201b to be shared.

Specifically, the upper work roll 201a has the first roll diameter portion w1 and the first roll diameter portion w1 from the roll end on one side (left side in FIG. 3) to the roll end on the other side (right side in FIG. 3) in the roll axis direction. A tapered portion w2 having a continuous outer peripheral surface with the roll diameter portion w1 of 1 and gradually reducing the roll diameter, and a second roll diameter portion w3 having a continuous outer peripheral surface with the tapered portion w2 and having a minimum diameter of the tapered portion w2. Have. The roll diameter of the first roll diameter portion w1 is equal to the maximum diameter of the tapered portion w2. That is, the upper work roll 201a is formed on one side (left side in FIG. 3) with the roll diameter of the first roll diameter portion w1 which is the same diameter as the maximum diameter of the tapered portion w2 from the center of the roll to the end of the roll. On the other side (right side in FIG. 3), the roll diameter is gradually reduced from the center of the roll toward the end of the roll.

On the other hand, the lower work roll 201b has the same shape as the upper work roll 201a and is arranged point-symmetrically.

That is, the lower work roll 201b has the first roll diameter portion w1 and the first roll from the roll end on the other side (right side in FIG. 3) toward the roll end on one side (left side in FIG. 3) in the roll axis direction. It has a tapered portion w2 having a continuous outer peripheral surface with the diameter portion w1 and gradually reducing the diameter of the roll, and a second roll diameter portion w3 having a continuous outer peripheral surface with the tapered portion w2 and having the minimum diameter of the tapered portion w2. That is, on the other side (right side in FIG. 3), the lower work roll 201b is formed with the roll diameter of the first roll diameter portion w1 which is the same diameter as the maximum diameter of the tapered portion w2 from the roll center to the roll end. On one side (left side of FIG. 3), the roll diameter is gradually reduced from the center of the roll toward the end of the roll.

The tapered portions w2 formed on the upper work roll 201a and the lower work roll 201b have the same gradient θ.

The upper backup roll 202a and the lower backup roll 202b have roll profiles corresponding to the roll profiles of the upper work roll 201a and the lower work roll 201b, respectively. The upper backup roll 202a has a first roll diameter portion b1 and a first roll diameter portion from the roll end on one side (left side in FIG. 3) to the roll end on the other side (right side in FIG. 3) in the roll axis direction. It has a tapered portion b2 having an outer peripheral surface continuous with b1 and gradually reducing the roll diameter, and a second roll diameter portion b3 having a continuous outer peripheral surface with the tapered portion b2 and having the maximum diameter of the tapered portion b2. Similarly, the lower backup roll 202b has the first roll diameter portion b1 and the first roll end portion b1 from the roll end on the other side (right side in FIG. 3) toward the roll end on one side (left side in FIG. 3) in the roll axis direction. It has a tapered portion b2 having a continuous outer peripheral surface with the roll diameter portion b1 and gradually reducing the roll diameter, and a second roll diameter portion b3 having a continuous outer peripheral surface with the tapered portion b2 and having the maximum diameter of the tapered portion b2. .. The roll diameter of the first roll diameter portion b1 is equal to the minimum diameter of the tapered portion b2.

As shown in FIG. 3, the upper work roll 201a and the upper backup roll 202a, and the lower work roll 201b and the lower backup roll 202b have profiles corresponding to each other. As a result, the area in contact between the upper work roll 201a and the upper backup roll 202a, and the lower work roll 201b and the lower backup roll 202b becomes large, so that the increase in Hertz stress at the contact portion is suppressed, and the rolls 201a, 202a, and 201b are respectively. , 202b surface damage can be suppressed.

The tapered portion w2 of the upper work roll 201a and the lower work roll 201b is provided at least at a position including a portion in contact with the plate end portions Se on both sides of the cast strip S, as in the case of the double-sided tapered work roll shown in FIG. With this configuration, the plate end portion Se of the cast strip S is rolled by the tapered portion W2 at which the upper work roll 101a is reduced in diameter, and the flat deformation of the upper work roll 101a is suppressed. Thereby, the occurrence of edge drop of the cast strip S can be suppressed. Since the position where the tapered portion w2 can be provided is the same as the position described with reference to FIG. 2, the description thereof is omitted here.

The roll profile of the work roll and the backup roll of the inline mill 100 according to the present embodiment may be roll profiles other than those described in FIGS. 2 and 3. For example, just as the upper work roll 101a and the upper backup roll 102a in FIG. 2 have two tapered portions W2 and B2, the lower work roll 101b and the lower backup roll 102b may be provided with similar tapered portions, respectively. .. As a result, both plate end portions Se of the cast strip S are rolled by the tapered portion W2 on both the upper surface side and the lower surface side. Alternatively, for example, in the upper work roll 201a or the lower work roll 201b of FIG. 3, a tapered portion may be formed at a portion where the first roll diameter portion w1 is in contact with the plate end portion Se of the cast strip S. In either case, the occurrence of edge drop of the cast strip S can be suppressed as in the case of FIGS. 2 and 3.

(Method of determining the shape of the taper part)
The shapes of the tapered portions W2 and w2 shown in FIGS. 2 and 3, that is, the length of the tapered portion in the plate width direction (hereinafter referred to as “tapered width”) and the gradient θ are determined by, for example, experiments and calculations. It is determined. The taper width correlates with the edge drop occurrence range, and the gradient θ correlates with the edge drop amount. By using these correlations, the shape of the tapered portion can be determined.

To explain an example of a method for determining the shape of the tapered portion, first, the cast strip S rolled to a desired plate thickness by the in-line mill 100 is rolled by a later reverse rolling mill. Then, the in-line mill 100 is set to the edge drop generation range and the edge drop amount on the first pass side of the reverse rolling of the cast strip S in which plate defects such as plate breakage and cracking did not occur during rolling in the reverse rolling mill. The maximum allowable edge drop occurrence range and edge drop amount. The shape of the tapered portion is formed by calculating the taper width and the gradient θ so that the edge drop generation range and the edge drop amount of the edge drop generated in the cast strip S rolled by the in-line mill 100 are equal to or less than the maximum values. Can be determined. For example, the shape of the tapered portion may be determined so that the edge drop amount is not more than the maximum allowable value in the range of at least 30 mm to 15 mm from the plate end to the plate center side of the cast strip S. The larger the gradient θ, the larger the edge drop amount, and the smaller the gradient θ, the smaller the edge drop amount.

The edge drop amount may not be limited in a range closer to the plate edge, for example, in the range from the plate edge to 15 mm in the above example. However, in such a range, when edge-up occurs in which the plate thickness becomes thicker with respect to the edge drop in which the plate thickness decreases at the plate end portion, if the edge-up is large, a problem occurs at the time of winding the cast strip S. Therefore, edge-up to the extent that such a defect does not occur is allowed. From the maximum value of the allowable edge-up amount, the minimum edge drop generation range and the edge drop amount allowed by the inline mill 100 may be set. The smaller the gradient θ, the smaller the amount of edge-up, and the more the occurrence of edge-up can be suppressed. As described above, the shape of the tapered portion can be determined from the allowable range of edge drop and edge up.

For example, as the tapered shape of the upper work roll 101a shown in FIG. 2, the upper work roll 101a and the lower work roll 101b having a roll diameter of 400 mm and a roll body length of 2000 mm, the roll diameter of 1200 mm, the upper backup roll 102a of the roll body length of 2000 mm, and the lower backup The roll 102b is tapered from a position 80 mm outside the plate edge toward the center of the plate by 5 mm (roll radius) / 100 mm (roll body length) to have a minimum diameter of 390 mm, a maximum diameter of 400 mm, and a taper width of 100 mm. A tapered portion may be formed.

[3.2. Lubricant supply device]
Since the work roll and the backup roll of the inline mill 100 according to the present embodiment have tapered portions, they have different diameters in the roll direction in the width direction. Therefore, the work roll and the backup roll have different peripheral speeds on the roll end side even if the peripheral speed at the center of the roll is the same. For this reason, slippage occurs between the rolls on the roll end side, the rolls are worn, and the roll profiles of the backup roll and the work roll do not match. Therefore, in addition to the above-mentioned profile addition, a lubricant may be further added to suppress the wear of the roll.

(composition)
As shown in FIG. 1, the lubricant supply device 103 for supplying the lubricant is provided on the inlet side of the in-line mill 100. The lubricant supply device 103 may supply the lubricant at least between the tapered portion of the work roll and the tapered portion of the backup roll.

Specifically, for example, in the case of the double-sided tapered work roll shown in FIG. 2, the lubricant supply device 103 is arranged so that the lubricant is supplied between the upper work roll 101a and the backup roll 102a of the tapered portion W2. do it. Since the tapered portion W2 of the upper work roll 101a is in contact with the plate end portion, metal flow in the width direction of the material is likely to occur, and wear may be promoted. Further, since the load between the plate and the work roll at the plate end portion, that is, the so-called stress, increases, the tapered portion W2 near the plate end portion is more than the first roll diameter portion W1 and the second roll diameter portion W3. Wear can be noticeable. As a result, by lubricating the tapered portion W2, the friction coefficient between the upper work roll 101a and the plate is reduced in addition to the wear caused by the speed difference between the upper work roll 101a and the backup roll 102a in the tapered portion W2. Therefore, it is possible to reduce the wear caused by rolling.

In the lubricant supply device 103, in addition to the tapered portion W2, a second roll diameter portion W3 having the same diameter as the minimum diameter of the tapered portion W2 supplies a lubricant between the work roll and the backup roll. You may. With this configuration, the upper work roll 101a and the backup roll 102a can also lubricate the second roll diameter portion W3, which tends to have a larger roll peripheral speed difference than the tapered portions W2 and B2, and reduce roll wear. be able to.

In addition to the tapered portion W2 and the second roll diameter portion W3, the lubricant supply device 103 may supply the lubricant at the first roll diameter portion W1 in contact with the portion having a constant plate thickness in the plate width direction. .. That is, the lubricant may be supplied between the upper work roll 101a and the backup roll 102a over the entire roll width of the work roll having the tapered portion W2. With such a configuration, it is possible to reduce the wear of the roll even in the vicinity of the central portion of the plate where metal flow in the width direction of the material is unlikely to occur.

Further, even in the case of the in-line mill 200 having the one-sided tapered work roll shown in FIG. 3, the lubricant supply device 103 may supply the lubricant between the work roll and the backup roll at the taper portion w2. good. With such a configuration, as in the case of the in-line mill 100 in FIG. 2, in addition to the wear caused by the speed difference, the coefficient of friction with the plate is reduced, so that the wear caused by rolling can also be reduced.

The lubricant supply device 103 may supply the lubricant at the second roll diameter portion w3 in addition to the taper portion w2. With this configuration, the upper work roll 201a and the upper backup roll 202a or the second roll diameter portion W3, which tends to have a larger roll peripheral speed difference than the tapered portions w2 and b2 of the lower work roll 201b and the lower backup roll 202b, are also lubricated. And the roll wear can be reduced.

Further, the lubricant supply device 103 may supply the lubricant at the taper portion w2, the second roll diameter portion w3, and the first roll diameter portion w1. That is, the lubricant may be supplied between the work rolls 201a and 201b and the backup rolls 202a and 202b over the entire roll width of the work roll having the tapered portion w2. With such a configuration, it is possible to reduce the wear of the roll even in the vicinity of the central portion of the plate where metal flow in the width direction of the material is unlikely to occur.

However, if the number of places to supply the lubricant increases, the configuration of the lubricant supply device becomes complicated, the amount of the lubricating oil used increases, and the lubrication cost increases. The point to be lubricated may be determined by comparing the effect of reducing the wear of the roll with the increase in the lubrication cost.

(Supply method)
As a supply method, for example, a stock solution of the lubricant may be sprayed on the surface of the backup roll by an air atomizing method. The supply amount may be, for example, 3 mmg / m ² . The amount of lubricating oil supplied may be controlled so that the amount of lubricant adhering to the surface of the backup roll becomes constant according to the change in roll speed.

(lubricant)
As the lubricant, a synthetic ester or a mixture of synthetic ester and vegetable oil may be used as a base oil, or a solid lubricant or an extreme pressure additive may be mixed. Preferably, a lubricant having a pour point of less than 0 ° C. and a viscosity of 60 cSt (temperature of 40 ° C.) or higher may be used. The reason why the flow point of the lubricant is less than 0 ° C. and the viscosity of 60 cSt (temperature 40 ° C.) is preferable is that if the conditions are not met, the lubricating oil solidifies in winter and is placed on the surface of the backup roll 102a. This is because the amount of oil that adheres, the so-called plate-out amount, is reduced, and the lubricity is lowered. In addition, in order to improve lubricity, it is necessary to increase the supply amount, which leads to an increase in cost. Therefore, by selecting the lubricant within the range of the above conditions, it is possible to suppress an increase in the basic unit of the lubricating oil and the equipment cost.

Further, as the lubricant, a fluorocarbon resin (Teflon (registered trademark)) may be sprayed. Fluorocarbon resin (Teflon®) is more expensive than lubricating oil mixed with other solid lubricants and extreme pressure additives, but it is advantageous in terms of wastewater treatment. In addition, since the fluorocarbon resin (Teflon (registered trademark)) forms a strong adsorption film and exerts a lubricating effect longer than the lubricating oil, it is not necessary to continuously supply it to the roll, and it is intermittent. May be supplied. When the fluorocarbon resin (Teflon (registered trademark)) is intermittently supplied, the supply amount may be, for example, 1 mmg / m ² .

<4. Summary>
The continuous casting equipment according to the present embodiment has been described above. In the continuous casting equipment according to the present embodiment, when the casting strip S is rolled to a predetermined plate thickness by an in-line mill, plate breakage caused by rolling inconsistency that occurs in the first pass of rolling in a subsequent reverse rolling mill is performed. It is possible to suppress the increase in manufacturing cost caused by. Further, it is possible to suppress edge drop in the in-line mill and improve the plate thickness accuracy in the plate width direction. As a result, it is possible to reduce the trim allowance of the trim that was performed before rolling with the reverse rolling mill, and it is possible to reduce the manufacturing cost and improve the yield.

Hereinafter, examples of the present invention will be described. This example was carried out in the manufacturing process of the cast strip S having the same structure as that of FIG. The cast strip S used in the examples was a high Si steel having a plate thickness of 2 mm and a plate width of 1200 mm and containing 3% of Si. The acceleration rate of the cooling drum from the start of casting was 150 m / min / 30 seconds, and the rotation speed of the cooling drum in the steady state was 150 m / min. As for the initial profile of the cooling drum, the initial profile was processed so that the plate crown of the cast strip S was 43 μm in a steady state. Further, in the in-line mill, rolling with a rolling reduction of 30% (plate temperature 1000 ° C.) was performed, and the plate thickness of the cast strip S on the exit side of the in-line mill was 1.4 mm. Rolling in the in-line mill was started 15 seconds after the start of casting (after the dummy sheet passed and the plate crown of the casting strip S became 150 μm or less).

In Comparative Example 1, the profiles of the work roll and the backup roll were both rolled in an in-line mill having a flat shape having the same roll diameter in the roll width direction. In addition, no lubricating oil was supplied. After rolling, it was pickled and then subjected to multi-pass rolling to a plate thickness of 0.2 mm with a Zenjimar rolling mill having a diameter of 60 mm.

In Comparative Example 2, 5 mm (roll radius) is provided on one side of each of the upper work roll and the lower work roll within a range of 80 mm on the center side of the plate and 80 mm on the other side from the reference point with respect to the plate edge. The backup roll was tapered with a taper of / 100 mm (roll body length) and arranged point-symmetrically, and the backup roll was rolled by an in-line mill having a flat shape having the same roll diameter in the roll width direction. In addition, no lubricating oil was supplied. Then, it was pickled and further subjected to multi-pass rolling to a plate thickness of 0.2 mm with a Zenjimar rolling mill having a diameter of 60 mm.

In the first embodiment, the upper work roll has a 5 mm (roll radius) / 100 mm (roll body length) in a range of 80 mm on the center side of the plate and 80 mm on the other side from the reference point with respect to the plate edge. Tapered. The upper backup roll was processed to have a profile corresponding to the upper work roll. In addition, no lubricating oil was supplied. Then, it was pickled and multi-pass rolled to 0.2 mm with a Zenzimer rolling mill having a diameter of 60 mm.

In the second embodiment, the upper work roll has a 5 mm (roll radius) / 100 mm (roll body length) in a range of 80 mm on the center side of the plate and 80 mm on the other side from the reference point with respect to the plate edge. Tapered. The upper backup roll was processed to have a profile corresponding to the upper work roll. Further, the diameter of the upper work roll was gradually reduced to the minimum diameter, and 3 mmg / m ^{2 of} a lubricant based on a synthetic ester was supplied to the surface of the upper backup roll. Then, it was pickled and multi-pass rolled to 0.2 mm with a Zenzimer rolling mill having a diameter of 60 mm.

In Comparative Example 1, when the casting strip S was not trimmed before the Zenzimer rolling, plate breakage occurred during the first pass rolling with the Zenzimer rolling mill. Further, even if 20 mm on one side was trimmed before rolling with Zenjimar, plate breakage occurred during rolling with a Zenzimer rolling mill. If one side was trimmed by 30 mm before rolling with the Zenjimar, no plate breakage occurred during rolling with the Zenjimar rolling mill. Therefore, in front of the Zenzimer rolling mill, the cast strip S having a plate width of 1200 mm was trimmed by a total of 60 mm, and a yield drop (60/1200 (trim width / plate width)) occurred.

In Comparative Example 2, the plate breakage did not occur even if the cast strip S was not trimmed before the Zenzimer rolling. However, due to the large Hertz stress between the work roll and the backup roll, severe spalling occurs on the surface of the backup roll after rolling 100 coils, and this surface defect is transferred from the work roll to the plate, resulting in product failure and upper work. It became necessary to rearrange the roles of the roll and the upper backup roll.

In Example 1, no plate breakage occurred even if trimming was not performed before rolling the Zenzimer. No spalling occurred even after rolling 190 coils. However, wear progressed at the portion where slippage occurred between the rolls. After rolling 190 coils, the plate shape could not obtain the allowable flatness, and it became necessary to rearrange the rolls of the upper work roll and the upper backup roll.

In Example 2, no plate breakage occurred even if trimming was not performed before rolling the Zenzimer. No spalling occurred even after rolling 300 coils. Further, due to the lubrication effect, the wear of the portion where the slip occurred between the rolls was suppressed, so that the plate shape had an acceptable flatness even after rolling with 300 coils.

From the above, according to the present invention, the casting strip S manufactured by the twin-drum type continuous casting equipment can be rolled without surface damage of the roll, the plate is not broken in the rolling in the next step, and the trim allowance is reduced. As a result, it was confirmed that the yield can be improved and the manufacturing cost can be reduced.

Although the preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, the present invention is not limited to these examples. It is clear that a person having ordinary knowledge in the field of technology to which the present invention belongs can come up with various modifications or modifications within the scope of the technical ideas described in the claims. , These are also naturally understood to belong to the technical scope of the present invention.

1 Casting strip S manufacturing process 10 Twin drum type continuous casting equipment 10a, 10b Cooling drum 11 Dummy sheet 12 Protrusion part 13 Dummy bar 15 Metal molten metal storage part 20 Antioxidant device 30 Cooling device 40 First pinch roll device 40a, 40b Pinch roll 100 In-line mill 101a, 101b, 201a, 201b Work roll 102a, 102b, 202a, 202b Backup roll 103 Lubricant supply device 60 Second pinch roll device 70 Winding device 88a, 88b Tension roll 89 Deflector roll

Claims (2)

A twin-drum type continuous casting device that forms a metal molten metal storage part by a pair of cooling drums and a side weir, and casts the metal molten metal stored in the metal molten metal storage part while rotating the pair of the cooling drums.
A rolling apparatus arranged on the downstream side in the casting direction of the twin-drum type continuous casting apparatus and rolling a casting strip, and a rolling apparatus.
Equipped with
The rolling apparatus includes a pair of work rolls consisting of an upper work roll and a lower work roll arranged above and below the casting strip, and a pair of backup rolls including an upper backup roll and a lower backup roll that support the pair of work rolls. It is a quadruple rolling apparatus having a roll, and a supply apparatus for supplying a lubricant between the work roll and the backup roll is provided.
The upper work roll and the lower work roll each have a tapered portion whose diameter is reduced from the center toward the end at a portion where one plate end portion of the cast strip is in contact, and the same diameter as the maximum diameter of the tapered portion. It has a first roll diameter portion and a second roll diameter portion having the same diameter as the minimum diameter of the tapered portion.
The arrangement of the upper work roll and the lower work roll is point-symmetrical with each other.
Of the pair of backup rolls
The profile of the upper backup roll corresponds to the profile of the upper work roll.
The profile of the lower backup roll corresponds to the profile of the lower work roll.
The supply range of the lubricant supply device, the work roll and by comparing the effect and the lubricating incremental cost by reducing wear of the backup roll, (a) said tapered portion, (b) the tapered portion and the second 2 roll diameter, (c) the tapered portion, the second roll diameter and the first roll diameter, Ru is set to one of Tei, continuous casting equipment. A twin-drum type continuous casting apparatus that forms a molten metal storage section by a pair of cooling drums and side dams and casts the molten metal stored in the molten metal storage section while rotating the pair of cooling drums, and the twin. A rolling machine that is located downstream of the casting direction of the drum-type continuous casting device and rolls the casting strip.
Equipped with
The rolling apparatus has a pair of work rolls composed of an upper work roll and a lower work roll arranged above and below the casting strip, and a pair of backup rolls composed of an upper backup roll and a lower backup roll that support the pair of work rolls. It is a quadruple rolling apparatus having, and a supply apparatus for supplying a lubricant between the work roll and the backup roll is provided.
The upper work roll and the lower work roll each have a tapered portion whose diameter is reduced from the center toward the end at a portion where one plate end portion of the cast strip is in contact, and the same diameter as the maximum diameter of the tapered portion. It has a first roll diameter portion and a second roll diameter portion having the same diameter as the minimum diameter of the tapered portion.
The arrangement of the upper work roll and the lower work roll is point-symmetrical with each other.
Of the pair of backup rolls
The profile of the upper backup roll corresponds to the profile of the upper work roll.
The profile of the lower backup roll corresponds to the profile of the lower work roll.
By comparing the effect of reducing wear of the work roll and the backup roll with the increase in lubrication cost, the supply range of the lubricant by the supply device is determined by (a) the tapered portion, (b) the tapered portion and the first. 2 roll diameter portions, (c) the tapered portion, the second roll diameter portion, and the first roll diameter portion are set in order of priority.
A rolling method in which a lubricant is supplied between the work roll and the backup roll by the supply device, and the cast strip is rolled by the rolling device.

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