JP6599462B2 - Endless and arranged rolling conversion continuous casting and rolling equipment, and endless and arranged rolling conversion continuous casting and rolling method - Google Patents

Description

The present invention relates to a continuous casting and rolling equipment and method capable of switching between endless rolling and batch rolling, which can reduce the amount of waste during casting conversion or initial casting and increase the actual yield.

  The conventional continuous casting and rolling equipment has a structure shown in Patent Document 1, that is, a system having a heat-retaining furnace between a casting machine and a rolling line, and a primary rolling line and a secondary as shown in Patent Document 2. A system having a coiler or a coil box between the rolling line and the rolling line is known.

In particular, Patent Document 1 discloses a method and equipment for performing endless rolling after continuous casting depending on the type of steel or depending on work conditions, or performing batch rolling by cutting a slab after continuous casting if a temperature at which rolling is possible is not ensured. Has been proposed.

In continuous casting and endless rolling where the continuous casting speed is slower than the rolling speed and the slabs are connected from casting to rolling, rolling is slower than batch rolling where rolling and continuous casting are performed separately. I do not get. In the case of rolling, rolling is difficult if a predetermined temperature condition is not satisfied. Therefore, in continuous casting and endless rolling, it is important to match the slab temperature in the final rolling stand.

For these reasons, even if the equipment is capable of endless batch rolling, it is difficult to perform endless rolling at the initial stage of casting if the temperature of the slab is low, and it is necessary to start from batch rolling. There is a problem of not becoming.

JP 2009-508691 A European Patent Application No. 0841995

An object of the present invention is to increase the actual yield of the process by reducing the portion of the endless batch rolling conversion continuous casting and rolling equipment that is inevitably scrapped at the time of casting conversion or at the initial stage.

In order to achieve the above-mentioned problems, the present invention provides, as an embodiment, an endless batch rolling conversion including a continuous casting part, at least two or more rolling parts, and a coil box disposed between the rolling parts. A continuous casting and rolling facility operating method, in which a continuous casting stage for producing a slab, a primary rolling stage for reducing the thickness of the slab, and a predetermined distance from the tip of the slab are cut at the initial stage of casting. Endless batch rolling conversion continuous casting and rolling, including a cutting step to perform, a passing step in which a continuously supplied slab passes through the coil box, and a secondary rolling step to reduce the thickness of the slab that has passed through Provide a method.

  At this time, in the primary rolling step, the thickness of the slab can be reduced by a reduction amount smaller than the steady reduction amount.

  In addition, a heating step of increasing the temperature of the slab passing between the cutting step and the passing step may be further performed.

  In one embodiment of the present invention, the heating step can raise the slab to a temperature higher than the steady temperature rise.

  In one embodiment of the present invention, the heating stage can be heated to a temperature that is 20-30 ° C. higher than the steady temperature increase temperature.

  Further, after the first rolling stage, a slab temperature measuring stage for measuring the temperature of the slab is performed, and the slab can be cut based on the temperature of the slab.

  Moreover, the said slab temperature measurement step can measure the temperature of the slab which passed the said 1st rolling part.

  In one embodiment of the present invention, the cutting step predicts a temperature at which the slab passes through the second rolling part, and cuts the slab until the second rolling part passing temperature is equal to or higher than a rollable temperature. Can do.

  In an embodiment of the present invention, the second rolling step may be rolled with a reduction amount that is greater than the steady reduction amount.

  In one embodiment of the present invention, the first rolling stage and the second rolling stage may return to a steady reduction amount after a certain time has elapsed, and the first rolling step is to gradually increase the reduction amount. Can do.

In one embodiment of the present invention, a continuous cast part, a first and a second rolled part that are arranged along a traveling direction of a slab produced from the continuous cast part and that roll the slab, and the first And a coil box that is arranged between the second rolling part and passed through the first rolling part is coiled and uncoiled at the time of batch rolling, and passes through as it is when endless, and the first rolling part, A cutting machine arranged between the coil box, a slab temperature measuring sensor arranged behind the first rolling part, the first and second rolling parts, a coil box, a cutting machine, and a temperature measuring sensor. a endless batch conversion facility including a linked control unit and said control unit, said cutting machine so as to cut the initial casting unit based on the temperature measuring sensor readings during the initial casting, the coil Box controls to pass the slab, which is connected to the continuous casting unit.

  At this time, the heating unit may further include a heating unit that is disposed between the cutting machine and the coil box and raises the temperature of the passing slab. It can be controlled to raise the temperature higher.

  In one embodiment of the present invention, the control unit reduces the reduction amount of the first rolling part from the steady reduction amount, increases the reduction amount of the second rolling part from the steady reduction amount, and sets the final thickness. Can be maintained.

  In one embodiment of the present invention, the coil box is of a carousel type, and when the coil box passes the slab, the mandrel of the coil box is located above the slab to pass. Can do.

  In one embodiment of the present invention, the heating unit includes an inductive heater having one open side, and the inductive heater can be configured to be able to enter and retreat in a lateral direction of the slab.

  In one embodiment of the present invention, a pusher and a pillar disposed between the heating unit and the cutting machine and for removing the cut slab from the path of the slab may further be included.

According to the present invention, in the endless batch rolling conversion continuous casting and rolling equipment, it is possible to increase the actual yield of the process by reducing the portion that is inevitably scrapped at the time of casting conversion or at the initial stage.

In one Embodiment of this invention, it is the schematic when batch rolling is performed. In one Embodiment of this invention, it is the schematic when endless rolling is performed.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 show an embodiment of the present invention. FIG. 1 shows a state where the endless batch rolling conversion continuous casting and rolling equipment according to the embodiment of the present invention performs batch rolling, and FIG. 2 shows that the endless batch rolling conversion continuous casting and rolling equipment performs endless rolling. The situation is shown.

As shown in FIG. 1, the endless batch rolling conversion continuous casting and rolling equipment according to an embodiment of the present invention is arranged along the traveling direction of a continuous casting part 10 and a cast piece produced from the continuous casting part. The first rolling unit 20 for rolling the slab, the temperature measuring sensors 110, 111, 112, 113, 114 for measuring the temperature of the slab that has passed through the first rolling unit 20, and the first rolling unit 20 The cutting machines 30 and 40 capable of cutting the slab passing through, the heating unit 50 for heating the uncut slab, and the slab passing through the first rolling unit 20 and the heating unit 50 are coiled during batch rolling. A coil box 60 that is uncoiled and configured to pass when endless, a second rolling unit 70 that is arranged alongside the coil box, and a run-out table that cools a slab that has been rolled and is scraped 0, a cutting machine 90 that cuts an amount corresponding to one coil, a coiler 100, the first rolling unit 20, the second rolling unit 70, the coil box 60, the cutting machines 30, 40, 90, and a temperature measurement sensor 110, 111, 112, 113, and 114 and the control part 120 connected.

  In the present invention, the continuous casting part 10 can be applied to any configuration as long as it can perform continuous casting. In this embodiment, the continuous casting part 10 has a plurality of segments (not shown) arranged below the mold to cool the slab.

  The 1st rolling part 20 is arrange | positioned along with the continuous casting part 10, squeezes the slab which passed the continuous casting part, and rolls it to target thickness. In the embodiment of FIGS. 1 and 2, the rolling unit having three stands is shown. However, the number of stands may be increased or decreased as necessary. The first rolling unit 20 is connected to the control unit 120, and the amount of reduction can be adjusted by a signal from the control unit 120.

  The temperature measurement sensor 110 is disposed at the rear end of the first rolling section 20 and measures the temperature of the slab after the first rolling is completed. The temperature measurement sensor 110 may be configured as either a contact type or a non-contact type, and includes not only the rear end of the first rolling unit 20 but also the front and rear ends of the heating unit 50, the front and rear ends of the second rolling unit 70, and It is installed at many points such as the rear end of the continuous casting machine 10 and can sense the temperature of the slab passing therethrough.

  In the embodiment of the present invention, three cutting machines 30, 40 and 90 are provided, two are arranged at the rear end of the first rolling unit 20, and are also arranged at the front end of the coiler 100. In the case of the cutting machine 30 arranged at the rear end of the first rolling section 20, a plurality of cutting machines are arranged depending on the thickness of the slab, but it is of course possible to use only one cutting machine.

  In the present embodiment, the heating unit 50 is composed of an inductive heater with one side surface opened. That is, one side surface is opened, and it is configured by a heating unit having an overall reverse “ko” shape when viewed from the front. The inductive heater can be connected to the moving means so as to be able to enter and retreat in the lateral direction of the slab, and may be removed from the path of the slab when heating is unnecessary.

  Further, temperature measuring sensors 111 and 112 can be disposed at the front and rear ends of the heating unit 50, whereby the control unit 120 can control the heating unit 50 to raise the temperature to a desired temperature. .

  On the other hand, although not shown in FIGS. 1 and 2, a pusher and a pillar (not shown) may be disposed in the space between the cutting machines 30 and 40 and the heating unit 50. The pusher and the pillar are removed from the path of the slab by extruding the slab cut by the cutting machines 30 and 40, and other devices for removing the cut slab are applicable instead of the pusher and the pillar. Needless to say.

  In the present embodiment, the coil box 60 includes two mandrels 61 and 62, and may be configured as a carousel type having a structure in which coiling and uncoiling are alternately performed while rotating along a circular track. . In addition, as shown in FIG. 2, when endless rolling is performed, the coil box 60 is lifted so as to be positioned above the slab through which all the plurality of mandrels pass so as not to block the traveling path of the slab. Although it can have a structure, it is not restricted to this, It can also have another structure, for example, the structure which passes between the mandrels 61 and 62, for example.

  Although the 2nd rolling part 70 is arrange | positioned along with the coil box 60 and is shown as having five rolling stands in this embodiment, it is not restricted to this, A several rolling stand can be included. In addition, the rolling stands may be arranged side by side, but may be separated.

  The second rolling unit 70 rolls the slab having a reduced thickness while passing through the first rolling unit 20 by a plurality of rolling stands, and reduces the slab to the final target thickness. At this time, whether or not the temperature at which the second rolling part 70 can be rolled is maintained can be managed by the temperature measuring sensors 113 and 114 arranged at the front and rear of the second rolling part 70 by the control unit 120.

  The run-out table 80 is configured to cool the slab that has been scrapped by a cooling water supply device disposed on the upper side while allowing the slab to pass through a certain section on the upper side of the roller. Before being wound, the cutting machine 90 cuts the slab that has passed through the run-out table 80 so as to be an amount of one coil.

  The control unit 120 is connected to each device, and can adjust other devices based on information of each device. In particular, in the present invention, at least the first rolling unit 20, the cutting machines 30 and 40, the heating unit 50, the coil box 60, the second rolling unit 70 and the temperature measurement sensor 110 are connected and based on the temperature value of the temperature measurement sensor 110. The first rolling unit 20, the cutting machines 30 and 40, the heating unit 50, the coil box 60, and the second rolling unit 70 are controlled.

In such a structure, when endless rolling is started in the initial stage of casting, a temperature at which rolling is possible before the portion where the slab temperature in the initial casting stage is not ensured passes through the last stand of the second rolling unit 70. Is impossible. In addition, when batch rolling is performed, when converting to endless rolling with the structure of this embodiment, the mandrels 61 and 62 must be moved in the coil box 60, and thus it is necessary to unwind the previously wound coil. It is. Thereby, the slab continuously cast while the coil is unwound must be cut and scraped by the cutting machines 30 and 40. Thus, when scraping the slab cast while winding the coil, the slab of 10 tons or more is scrap-processed, which greatly affects the actual yield.

Therefore, in the endless batch rolling conversion continuous casting and rolling equipment of the present invention, the control unit 120 starts the endless rolling in which the coil box is passed as it is at the beginning of casting, and cuts the tip of the slab by a certain distance. At this time, the cutting distance can be adjusted by the control unit 120 so that the temperature of the slab before passing through the last stand of the second rolling unit 70 becomes a temperature at which rolling is possible.

  In order to reduce the cutting distance, in the embodiment of the present invention, when the heating unit 50 is in a steady state, the slab is heated to a temperature higher than the temperature at which the slab is heated, thereby compensating for a low temperature in the initial stage. Here, the steady state means when casting is stable.

  That is, when the temperature of the slab is relatively low in the early stage of casting, a larger amount of heat is supplied than the amount of heat heated in the middle of casting. At this time, the heating amount and the temperature at which the slab is raised can be heated to a temperature higher by 20 to 50 ° C. than the steady state, and the temperature in the second rolling section 70 can be ensured at the initial stage. If the difference in temperature rise is less than 20 ° C, the effect of additional heating is small, and if the difference in temperature rise exceeds 50 ° C, the quality of the slab may be affected. Equipment also deteriorates and may shorten the service life.

  In addition, the control unit 120 operates by reducing the rolling amount of the first rolling unit 20 from the steady state rolling amount and increasing the rolling amount of the second rolling unit 70 from the steady state rolling amount at the initial stage of casting. The temperature at the second rolling part 70 can be secured by increasing the plastic heat generation of the slab at the second rolling part 70.

  In particular, in the case of the heating unit 50, since the heating efficiency increases as the slab thickness increases, the efficiency of the heating unit 50 is reduced by reducing the reduction amount of the first rolling unit 20 from the steady state reduction amount. The amount of heating provided to the slab can be increased.

  In the case of the rolling parts 20 and 70, in a steady state, in order to prepare for the case where there is a problem such as an intermediate equipment trouble, the maximum value of the rolling reduction capacity is not used, and it is operated with a certain margin. However, at the initial stage of casting, the control unit 120 utilizes the marginal reduction amount of the second rolling part 70 to reduce the reduction amount of the first rolling part 20 so that more reduction is performed in the second rolling part 70. Thus, the low temperature of the initial slab is covered by utilizing the plastic heat generation of the second rolling part 70.

  On the other hand, after the initial slab has passed, if the temperature of the slab is secured, the control unit 120 increases the reduction amount of the first rolling unit 20 to a steady state reduction amount, and the second rolling unit 70 The reduction amount is lowered to the steady reduction amount so that all the rolling parts 20 and 70 can have a margin reduction amount. At this time, the change of the amount of reduction of the 1st rolling part 20 and the 2nd rolling part 70 can be changed gradually.

  However, even if the control of the amount of reduction and the control of the heating unit 50 are performed as described above, the second rolling unit 70 may not be able to secure the temperature at which rolling can be performed in a part of the initial casting. Therefore, the control unit 120 measures the temperature of the slab that has passed through the first rolling unit 20 by the temperature measurement sensor 110 disposed on the exit side of the first rolling unit 20, and provides the measured temperature by the heating unit 50. Predicting the temperature of the slab when passing through the second rolling part 70 in consideration of the possible amount of heat and the amount of heat taken away from the slab while passing through the heating part 50, the coil box 60 and the second rolling part 70 When this temperature is lower than the rollable temperature, the section of the slab is cut by the cutting machines 30 and 40.

  On the other hand, the control unit 120 applies a reduction amount after the tip of the initial slab passes through the first rolling part 20 to prevent a collision that may occur when the slab is initially taken into the first rolling part 20. It can also be controlled.

The operation method of the above endless batch rolling conversion continuous casting and rolling equipment will be described.

  As shown in FIG. 2, the coil box 60 starts casting in a state where the mandrels 61 and 62 are moved to the upper side of the traveling path of the slab so that the endless rolling can be started at the initial stage of casting.

  After the continuous casting stage in which the slab is continuously cast by the continuous casting machine, the first rolling part 20 is reduced after the slab tip has passed so that the problem of taking in the first rolling part 20 does not occur at the beginning of casting. The first rolling stage is started. At this time, a temperature measurement step of measuring the temperature of the slab that has passed through the first rolling part 20 by the temperature measurement sensor 110 is performed, and the temperature at which the slab passes through the second rolling part 70 based on the corresponding temperature. If the temperature value is lower than the rollable temperature, a cutting step of cutting by the cutting machines 30 and 40 is performed. In the cutting stage, it is possible to cut the distance obtained from experience without the temperature measurement stage, but based on the temperature value in the temperature measurement stage, the cutting distance can be shortened and the actual yield is improved. Can bring.

  The cut slab is removed from the path of the slab, and the slab connected to the continuous casting unit 10 without being cut is subjected to a heating stage in which the temperature is raised by the heating unit 50. In the first rolling section 20, the amount of reduction in a steady state is achieved in the first rolling stage so that the temperature rise efficiency can be increased to provide more heat and induce a temperature rise due to plastic heat generation at the rear end. The reduction by a smaller reduction amount and insufficient reduction in the first rolling part 20 is compensated by performing further reduction in the second rolling part 70 from the steady state in the second rolling stage described later.

  After the heating stage, a passing stage in which the slab passes through the coil box 60 is performed, and then the second rolling stage 70 performs the second rolling stage. As described above, in the second rolling stage, the slab is squeezed by a reduction amount larger than the reduction amount in the steady state, and the portion not reduced in the first rolling stage is compensated.

  According to the method of the present embodiment, the coil box is controlled so that endless rolling can be performed in the early stage of casting, and the portion that is not subjected to endless rolling is cut, so that scrap generated at the time of changing the endless arrangement or in the early stage of casting. The amount can be reduced, and the actual yield can be improved.

In addition, only about 20-30% of scrap generated from conversion from batch rolling to endless rolling is utilized by utilizing increased heating and plastic heat generation so as to reduce the portion where endless rolling is not performed. Can be converted to batch and endless rolling, which is very useful for improving the actual yield.

Table 1 below is a comparison table comparing the time when the initial rolling was performed under the steady-state endless batch rolling conversion continuous casting and rolling equipment conditions, and the time when the method of the present invention was performed.

  The reduction amount of the first rolling part is decreased from the steady state, and the reduction amount of the second rolling part is increased instead. The total reduction amount is the same, and the heating amount of the heating part is further increased by 45 ° C. from the steady state. The temperature was raised. As a result, a difference of about 20 ° C. was generated in the outlet side temperature of the initial second rolling part, thereby reducing the amount of wasted scrap dramatically and improving the actual yield.

DESCRIPTION OF SYMBOLS 10 Continuous casting part 20 1st rolling part 30 and 40 Cutting machine 50 Heating part 60 Coil box 70 2nd rolling part 80 Runout table 90 Cutting machine 100 Coiler 110-114 Temperature measurement sensor 120 Control part

Claims (11)

A continuous casting and rolling method for an endless batch rolling conversion facility comprising a continuous casting part, at least two or more rolling parts, and a coil box disposed between the rolling parts,
Continuous casting stage to produce slabs;
A primary rolling step of reducing the thickness of the slab by a first rolling part;
A cutting step of cutting a certain distance from the tip of the slab at the beginning of casting,
A passing stage in which a continuously supplied slab passes through the coil box;
A secondary rolling step of reducing the thickness of the slab passing through the coil box by the second rolling part;
Including
After the primary rolling step, a slab temperature measurement step is performed to measure the temperature of the slab that has passed through the first rolling part,
The cutting step predicts the temperature when the slab passes through the second rolling part from the temperature of the slab passing through the first rolling part, and the second rolling predicted from the measured temperature of the slab. Continuous casting and rolling method for endless batch rolling conversion equipment interrupted when the part passing temperature is higher than the hot rolling temperature. After the cutting step is interrupted, the primary rolling step increases the thickness reduction amount of the slab, and the secondary rolling step decreases the thickness reduction amount of the slab. The continuous casting and rolling method of the endless batch rolling conversion equipment according to claim 1. The continuous casting and rolling method for an endless batch rolling conversion facility according to claim 2, further comprising a heating step of increasing the temperature of the slab between the cutting step and the passing step. 4. The continuous casting and rolling method for an endless batch rolling conversion facility according to claim 3, wherein after the cutting step is interrupted, the heating step reduces the temperature increase temperature by 20 to 50 ° C. 5. The continuous casting and rolling method for an endless batch rolling conversion facility according to claim 2, wherein the primary rolling step gradually increases the amount of reduction. Continuous casting part,
First and second rolling sections that are arranged along the direction of travel of the slab produced from the continuous casting section and roll the slab,
A coil box that is arranged between the first and second rolling parts, and the slab that has passed through the first rolling part is coiled and uncoiled during batch rolling, and is passed as it is when endless, and
A cutting machine disposed between the first rolling section and the coil box;
A slab temperature measurement sensor disposed behind the first rolling part;
An endless batch rolling conversion facility including a control unit connected to the first and second rolling units, a coil box, a cutting machine, and a temperature measurement sensor,
The control unit predicts a temperature when the slab passes through the second rolling part based on the measured value of the temperature measurement sensor during initial casting, and the second predicted based on the measured value. An endless batch rolling conversion facility in which the initial casting part is cut until the temperature at which the rolling part passes becomes equal to or higher than the temperature at which hot rolling is possible, and the coil box is controlled so as to pass the slab connected to the continuous casting part. continuous casting and rolling equipment. It further includes a heating unit that is disposed between the cutting machine and the coil box and raises the temperature of the passing slab,
The continuous casting and rolling of the endless batch rolling conversion equipment according to claim 6, wherein the control unit performs control so as to reduce a temperature rise temperature of the slab after the cutting of the initial casting part is completed. Facility. The controller is configured to increase a reduction amount of the first rolling part and reduce a reduction amount of the second rolling part to maintain a final thickness after the cutting of the initial casting part is completed. The continuous casting and rolling equipment of the endless batch rolling conversion equipment according to claim 7. The coil box is composed of a carousel type including a plurality of mandrels,
The continuous casting and rolling equipment of the endless batch rolling conversion equipment according to claim 6, wherein when the coil box passes the slab, a mandrel of the coil box is located above the slab to pass. . 8. The endless batch rolling according to claim 7, wherein the heating unit includes an inductive heater whose one side surface is opened, and the inductive heater is configured to be able to enter and retreat in a side direction of the slab. Continuous casting and rolling equipment for conversion equipment . The endless batch rolling conversion according to claim 7, further comprising a pusher and a pillar disposed between the heating unit and the cutting machine for removing the cut slab from a path of the slab. Equipment continuous casting and rolling equipment.

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