JP2009173993A - Apparatus for watering cooling cast slab - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a watering cooling apparatus by which the warp of stacked cast slabs is prevented and at the same time, the cast slab can efficiently be cooled without lowering productivity and increasing cost. <P>SOLUTION: The apparatus for watering cooling the high-temperature cast slabs 1 stacked after casting, includes a water-spraying device 10 for watering cooling both side surfaces in the longitudinal direction of the stacked high temperature cast slabs 1, and a heat-insulating structural member 6 for covering the upper surface of the cast slab 101 positioned at the uppermost step of the stacked high temperature cast slabs 1. The heat-insulating structural member 6 is preferably set ascendably/descendably with a winding-up system of wire 7, etc., onto a drum 5, in the upper surface and the upper part of the cast slab 101 positioned at the uppermost step. Further, the heat-insulating structural member 6 is preferably formed by successively connecting steel-made box-type structural parts 3, in which the lower face is opened and the inner part is spaced. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention cools the side surfaces of the laminated high-temperature slab slabs by sprinkling and efficiently cools the upper surface of the uppermost slab with a heat insulating structure without causing warpage of the slabs. The present invention relates to a sprinkling water cooling device for slab slabs.

  When cooling a high-temperature slab slab after continuous casting, a temperature difference occurs between the front and back surfaces of the slab slab during the cooling process, and this causes a difference in thermal shrinkage due to this temperature difference and expansion due to phase change. As a result, the slab is likely to warp, and this warp remains even after the slab has been cooled. The warp of the slab slab is likely to appear remarkably when the surface temperature of the slab before water spray cooling is 600 ° C. or higher.

  As a conventional technique for preventing warpage of a slab when cooling a high-temperature slab, for example, methods disclosed in the following Patent Documents 1 to 3 and the like are known.

  In Patent Document 1, the continuously cast laminated slab is allowed to cool in the atmosphere until the surface temperature of the side surface becomes 600 ° C. or lower, and then both side surfaces excluding a predetermined range from the upper surface of the laminated uppermost slab. A method of water spray cooling is disclosed. Patent Document 2 discloses a method for cooling a slab by periodically repeating watering treatment and watering stop treatment on a high-temperature slab after continuous casting.

  The cooling method disclosed in the above document is an excellent cooling method that can significantly reduce the occurrence of warpage of the slab, but it is difficult to eliminate the slab warpage. In order to eliminate the warpage of the slab, water cooling in a range below a predetermined slab surface temperature or a cooling method by repeating sprinkling treatment and water spray stop treatment is not sufficient. It is important to take measures to actively reduce the temperature difference from the back surface, and it is necessary to develop a cooling device for that purpose.

  As a method of actively reducing the temperature difference between the front and back surfaces of the slab, Patent Document 3 discloses the following cooling method. That is, a method for cooling a slab is disclosed in which water droplet adhesion prevention treatment is performed on the upper surface of the uppermost slab of a laminated high temperature slab, and cooling water is sprayed on both side surfaces in the longitudinal direction of the high temperature slab. In this document, as a specific example of water droplet adhesion prevention treatment, a method of loading a thick steel plate on the upper surface of the uppermost slab is described, but the transportation, loading and removal work of this thick steel plate requires a great amount of man-hours and costs. Furthermore, there is a problem that the number of stacked slabs to be cooled is reduced by the amount of the thick steel plate.

JP 2006-55865 A (Claims and paragraphs [0025] to [0027]) Japanese Patent Application No. 2007-36640 (Claims and paragraphs [0015] to [0018]) JP 11-286728 A (Claims and paragraph [0004])

  As described above, the prior art relating to cooling of a high-temperature slab cast has the following problems (a) and (b). That is, (a) the slab slab is sprinkled and cooled in a range where the surface temperature is, for example, 600 ° C. or less, or the cooling method in which the sprinkling treatment and the sprinkling stop treatment are combined with this, the slab slab warps. It is difficult to prevent drastically, and (b) it is possible to prevent slab warpage by a method of loading a water droplet adhesion prevention material such as a thick steel plate on the upper surface of the uppermost slab of the laminated high temperature slab However, there is a problem that it is necessary to transport, load and remove the thick steel plate for preventing water droplets, resulting in a reduction in productivity and an increase in cost.

  The present invention has been made in view of the above problems, and the problem is that the side surface of the laminated high-temperature slab slab is water-cooled and the upper surface of the uppermost slab is kept warm by a heat insulating structure. It is an object of the present invention to provide a sprinkler cooling apparatus that can efficiently cool a slab without preventing the slab from warping and at the same time reducing productivity and increasing costs.

  The cooling field for the slab slab is highly heated and in a steam atmosphere, and heat resistance and water resistance are particularly required for electrical equipment and a structure that does not generate thermal strain in mechanical devices. Therefore, more specifically, the object of the present invention is to satisfy the above-mentioned requirements, and to continuously cover and remove the top surface of the uppermost slab with the above-mentioned heat insulation structure without performing manual intervention. Another object of the present invention is to provide a water spray cooling device capable of water cooling the side surfaces of laminated slab cast pieces.

  In order to solve the above problems, the present inventors have made a water spray cooling device that does not cause residual warpage of the slab (hereinafter also simply referred to as “warp”) even when water spray cooling is performed from a high temperature of 600 ° C. or higher. After studying and developing, the following findings (a) and (b) were obtained, and the present invention was completed.

  (A) The process of warping in the slab is as follows. FIG. 1 is a diagram schematically showing a warp generation process in a slab. FIG. 1 (a) shows a state immediately after the start of sprinkling cooling, and FIG. 1 (b) shows an uppermost slab after that. (C) shows a state in which the uppermost slab has returned to a horizontal state, and (d) further shows a state in which the upper slab has progressed downward. Are shown respectively.

  (A-1) When the high-temperature slab after continuous casting is sprinkled and cooled, the sprinkling is likely to be applied to the upper surface of the slab, and due to the cooling effect due to the latent heat of vaporization of the generated water vapor, Cooling at a more rapid rate than cooling at the lower surface. As a result, an upward warp (a warped convex shape) occurs due to a temperature difference between the upper surface and the lower surface of the slab (FIGS. 1A and 1B).

  (A-2) The warpage described in the above (a-1) then returns to the original horizontal state by the weight of the slab ((c) in the figure). However, as cooling progresses further, cooling of the lower surface of the uppermost slab proceeds with cooling water and water vapor, and the difference in the progress of cooling between the upper surface and the lower surface of the slab becomes smaller. Convex warpage). This downward warp remains as a residual warp ((c) in the figure).

  (B) In order to prevent the warp described in (a) above, water spray cooling is performed while reducing the temperature difference between the upper surface and the lower surface by covering the upper surface of the laminated uppermost slab with a heat insulating member. Is the most effective. As an apparatus having excellent heat resistance capable of repeatedly and stably performing coating and uncovering of the upper surface of the uppermost slab with a heat insulating member, a device having the following functions or mechanisms is preferable.

  (B-1) The heat insulating structural member is configured to be able to move up and down the upper surface of the slab cast slab positioned at the uppermost stage of the stacked high-temperature slab cast slab.

  (B-2) The heat insulating structural member is configured to be movable up and down by winding or rewinding a steel wire or chain attached to the member around the drum.

  (B-3) The heat insulating structural member has a box shape that covers the upper surface of the uppermost slab slab, the lower surface of the box shape is opened, and the inside is a space made of steel. It is configured.

  (B-4) The heat insulating structural member is a structure in which a steel box-shaped structure forms an integral structure in the longitudinal direction of a high-temperature slab cast piece or a box-shaped structure divided into two or more pieces is connected. Have

  This invention is completed based on said knowledge, The summary exists in the cooling method of the slab shown to following (1)-(5).

  (1) A water spray cooling device for laminated high-temperature slab slabs after casting, the water spray spraying device for sprinkling and cooling both longitudinal sides of the laminated high-temperature slab slabs A sprinkling cooling device for laminated high-temperature slab slabs, comprising: a heat insulating structural member that covers an upper surface of the slab slab located at the uppermost stage of the high-temperature slab slabs.

  (2) The heat insulating structural member is installed so as to be movable up and down above and above the upper surface of the slab slab positioned at the uppermost stage of the laminated high temperature slab slab. Water spray cooling device for laminated high temperature slab slabs.

  (3) The heat insulating structural member can be moved up and down by winding or unwinding a steel wire or chain for suspending the member attached to the member with a drum. The sprinkling cooling device for the laminated high-temperature slab slab described in 1.

  (4) The heat insulating structural member has a box shape covering the upper surface of the uppermost slab slab, the lower surface of the box shape is open, and the interior is a space. It is comprised by these. The sprinkling cooling apparatus of the lamination | stacking high temperature slab slab in any one of said (1)-(3) characterized by the above-mentioned.

  (5) The heat insulating structural member is formed by connecting the steel box-type structure in the longitudinal direction of the high-temperature slab slab, or by connecting two or more box-type structures. The sprinkling cooling device for laminated high-temperature slab slab according to (4) above.

  In the present invention, the “high temperature slab slab” means a slab slab whose surface temperature is in the range of 100 ° C. to 800 ° C.

  The phrase “divided box-shaped structures are connected to each other” means that the divided box-shaped structures are rigidly connected to each other or bendably connected.

  The water spray cooling device of the present invention water-cools the side surfaces of the laminated high-temperature slab slabs and keeps the upper surface of the uppermost slab with a heat insulating structure under good operability, thereby improving productivity. It is a water spray cooling device capable of preventing the occurrence of warpage of a slab and efficiently cooling a slab without causing a decrease and an increase in cost. Therefore, the slab slab cooling device of the present invention is a sprinkler cooling device that can stably cool the slab without causing device trouble in the cooling process of the slab slab in a high-temperature and steam atmosphere. Can be used extensively.

  The present invention, as described above, is a water spray cooling device for the laminated high temperature slab slab after casting, and a water spray device for water spray cooling both sides in the longitudinal direction of the laminated high temperature slab slab, A sprinkling and cooling device for laminated high-temperature slab slabs, comprising a heat-insulating structural member that covers an upper surface of the slab slabs positioned at the uppermost stage of the laminated high-temperature slab slabs (invention according to claim 1). Hereinafter, the contents of the present invention will be described in more detail.

  1. Basic test

  FIG. 2 shows a basic test method for preventing warpage of laminated slab cast pieces. The figure (a) shows the case where the upper surface of the uppermost slab is covered with glass wool, the figure (b) shows the case where the upper surface of the uppermost slab is covered with a heat insulating structural member made of a steel plate, and (C) shows a perspective view of a box-shaped heat insulating structural member made of steel plate.

  As test 1, as shown in FIG. 1 (a), the upper surface of the slab is covered by placing glass wool alone on the upper surface of the laminated slab slab, and the side surface of the slab slab laminated in this state is covered. Water sprinkled cooling. From the results of this test, it was found that when the upper surface of the uppermost slab slab is covered with glass wool, the warpage of the slab is clearly reduced as compared with the case where it is not covered with glass wool.

  As test 2, as shown in FIG. 2B, the upper surface of the slab is covered by placing a box-shaped heat insulating structural member made of steel plate on the upper surface of the laminated high-temperature slab slab, and laminated in this state. The side surface of the slab slab was water-cooled. As in the case of Test 1, when the upper surface of the slab slab was covered with a box-shaped heat insulating structural member, the warpage of the slab was clearly reduced.

  Therefore, based on the above test results, the best mode of the sprinkler cooling device for practical use was studied and developed.

2. Inventions according to Claims 2 and 3 In the invention according to Claim 2, the heat insulating structural member is installed so that it can be moved up and down above the upper surface of the slab slab positioned at the uppermost stage of the laminated high temperature slab slab. It is a sprinkling cooling apparatus of the lamination | stacking high temperature slab slab of Claim 1. Further, the invention according to claim 3 is the invention according to claim 2, wherein the heat insulating structural member can be moved up and down by winding or unwinding a steel wire or chain for suspending the member attached to the member with a drum. It is a water-cooling apparatus of the laminated high temperature slab cast described.

2-1. FIG. 3 shows a side view of a sprinkling cooling device for stacked slab cast pieces, and FIG. 3 (a) shows a state in which the heat insulating structural member is lowered and placed on the upper surface of the uppermost slab. FIG. 4B shows a state in which the heat insulating structural member is lifted and removed from the upper surface of the uppermost slab.

  As shown in FIG. 2A, the heat insulating structural member 6 is lowered from above the uppermost slab of the laminated slab slab 1 and placed on the upper surface of the uppermost slab, thereby covering the upper surface of the uppermost slab. To prevent heat dissipation from the top surface of the slab. When the heat insulating structural member 6 is lowered and placed on the upper surface of the slab cast 1 stacked and loaded on the carriage 4, the steel wire 7 or the chain for suspension of the member attached to the heat insulating structural member 6 is wound up. On the other hand, the heat insulation structure member 6 is lifted and removed by winding the steel wire 7 or the chain around the winding drum 5.

  When the cart 4 is put into and out of the cooling field of the slab slab, the heat insulating structural member 6 is raised, and when the cart 4 stops at a position below the heat insulating structural member 6, the heat insulating structural member 6 is lowered to Is placed on the upper surface of the uppermost slab of the high-temperature slab cast slab 1 loaded on the slab. Thereafter, cooling water is sprinkled from the watering nozzle onto the side surface of the loaded slab slab to cool the slab slab.

  As described above, the heat insulation structure member is suspended by a steel wire or a steel chain, and by using a method of raising and lowering, the thermal distortion of the drive unit due to the heat from the high temperature slab slab is avoided, and the operation Stability and durability of the device can be ensured. In order to further improve the corrosion resistance and heat resistance in a water vapor atmosphere generated during spray water cooling, it is preferable to use stainless steel as the material such as a wire.

  FIG. 4 is a front view of the sprinkling cooling device for laminated slab cast pieces (in the direction of arrow A in FIG. 3), and the heat-insulating structure member is lowered and placed on the upper surface of the uppermost slab and the heat-insulating structure from the upper surface. Represents the removal of members and water spraying on the slab slab side.

  In the figure, three trolleys 4 loaded with slab slabs 1 are simultaneously placed in a cooling field, and a heat insulating structural member 6 is lowered and placed on the upper surface of the uppermost slab slab 1 loaded on each trolley. Thus, an example of a water spray cooling device that covers the upper surface of the slab and cools the side surface of the loaded slab with water spray from the water spray nozzle 10 is shown. The elevating and lowering of the heat insulating structural member 6 is performed by winding or rewinding the steel wire 7 for suspending the heat insulating structural material on the winding drum 5 that rotates forward and backward. The take-up drum 5 is fixed to the take-up shaft 8, and rotates together with the take-up shaft 8 that rotates forward and backward by a chain 9 that is fed out from the lifting drive unit 11.

  As described above, the power transmission from the lifting drive unit 11 to the winding shaft 8 that drives and rotates the winding drum 5 that lifts and lowers the heat insulating structural member 6 is a power transmission system using a heat-resistant steel chain 9. It was adopted. Moreover, the raising / lowering drive part 11 is installed under the one end part of the winding shaft 8, for example, and the heat-insulating plate 12 which shields the radiant heat from a high temperature cast piece is provided, and the raising / lowering drive part 11 can be protected. preferable.

  FIG. 5 is a partial detailed view showing a connection state of the winding drum, the wire, and the heat insulating structural member. FIG. 5 (a) is a plan view (in the direction of arrow B in FIG. 4), and FIG. The side view (C direction arrow view in FIG. 4) is represented.

  In the example shown in the figure, the heat insulating structural member 6 is suspended by two steel wires 7 and the steel wire 7 is rotated by forward and reverse rotation of a winding drum 5 fixed to a winding shaft 8 that is driven to rotate. By winding or unwinding, the upper surface of the uppermost slab of the laminated slab cast slab 1 is moved up and down.

2-2. FIG. 6 is a side view showing an example of the elevating drive unit of the heat insulating structural member (as viewed in the direction of the arrow C in FIG. 4. In FIG. 6, the steel wire 7 and the link shown by the solid line) The mechanism 112 shows a case where the heat insulating structural member 6 is raised, and the steel wire 7 and the link mechanism 112 shown by broken lines show a case where the heat insulating structural member 6 is lowered.

  The example shown in the figure is an example in which the lift drive unit 11 is configured by combining the cylinder 111 and the link mechanism 112. Even when a small stroke cylinder is used, the stroke of the cylinder 111 is expanded by the link mechanism 112 with the link fulcrum 113 as a fulcrum, and the steel chain 9 for rotating the winding drum 5 is driven up and down. The descending and rising strokes of the structural member 6 can be further increased.

  In this example, even when the number of stacked slab slabs 1 is changed, the heat insulating structural member 6 is easily placed on the upper surface of the uppermost slab slab, covers the upper surface of the slab, and heat from the upper surface of the slab. It is an elevating drive mechanism that can reliably prevent diffusion. When the fluctuation amount of the number of stacked slab slabs 1 is small, it is possible to adopt a simple configuration in which the steel chain 9 is directly connected to the output side of the cylinder 111 without using the link mechanism 112.

  Here, as a drive rotation method of the winding drum 5, the following method can be adopted in addition to the method of converting the reciprocating motion obtained by the cylinder 111 into the rotational motion via the steel chain 9 or the like.

  FIG. 7 is a diagram showing another drive rotation method of the winding drum, where FIG. 7A is a plan view (corresponding to the arrow B direction in FIG. 4), and FIG. 7B is a side view. (C direction arrow view in FIG. 4).

  The example of the figure is an example in which the output shaft of the motor 13 is directly coupled to the winding shaft 8, unlike the examples shown in FIGS. 4 to 6. As the motor 13, a rotary actuator such as an electric motor, a hydraulic motor, an air motor or the like can be used according to the load necessary for driving the winding shaft 8 and the ascending / descending speed of the heat insulating structural member 6. It can also be interposed.

  1 above. As described in the basic test section, the upper surface of the uppermost slab slab of the laminated slab slab is covered with glass wool, or when covered with a box-shaped heat insulating structural member made of steel plate However, the heat dissipation from the upper surface of the slab slab was reduced, and the warpage of the slab was obviously reduced. For details of the box-shaped heat insulating structural member made of steel plate, the following 3. Therefore, here, a further description is added to the heat insulating structural member made of glass wool.

  FIG. 8 is a diagram showing an example of a heat insulating structural member in which glass wool is wrapped with a reinforcing material. The glass wool 2 is susceptible to damage such as wear due to placement on the upper surface of the uppermost slab cast, removal from the upper surface, or a lifting operation, and is inferior in operability. Therefore, as shown in the figure, by reinforcing with a net-like or frame-like reinforcing material 201, good operability and long life can be achieved while ensuring excellent heat insulation. The reinforcing material preferably has a net-like structure from the viewpoint of avoiding thermal distortion due to heat received from the high temperature cast slab, and it is more preferable to employ stainless steel as the material.

3. Inventions According to Claims 4 and 5 In the invention according to claim 4, the heat insulating structural member has a box shape covering the upper surface of the uppermost slab slab, the lower surface of the box shape is open, and the inside is It is a water spray cooling device of the lamination | stacking high temperature slab cast piece in any one of Claims 1-3 comprised by the steel box-type structure which is space. Further, the invention according to claim 5 is that the heat insulating structural member is a box-shaped structure in which the steel box-shaped structure forms an integral structure in the longitudinal direction of the high-temperature slab cast piece or is divided into two or more. The sprinkling cooling device for laminated high-temperature slab slabs according to claim 4, which is connected to each other.

  In the heat insulating structural member shown in FIG. 8, the upper surface of the slab slab and the reinforcing member 201 are in direct contact with each other. Since the surface temperature of the slab slab is a high temperature of about 500 ° C. to 800 ° C., there is a problem that the reinforcing material 201 is rapidly deteriorated and its life is shortened due to a temperature rise due to conduction heat transfer from the slab. Therefore, as a result of improving this point, it has been found that a heat insulating structural member having the following structure is effective.

  FIG. 9 is a view showing a state in which the upper surface of the uppermost slab slab is covered with a box-shaped heat insulating structural member, where FIG. 9A shows a plan view and FIG. 9B shows a side view.

  The feature of the heat insulating structural member 3 shown in the figure is that a box-shaped lower surface is open, and a space, that is, an air layer 302 is provided between the upper surface of the uppermost slab cast slab 101 and the box-shaped upper surface. There is. By adopting such a structure, the manufacturing cost can be reduced and a lightweight heat insulating structure member can be obtained as compared with the heat insulating structure member incorporating the glass wool shown in FIG. Further, since the space is provided between the upper surface of the slab cast slab 101 and the box-shaped upper surface, the heat load of the heat insulating structural member can be reduced, so that the life of the heat insulating structural member can be extended.

  Even when the box-shaped heat insulating structural member is placed on the slab cast slab 101 having various slab widths, it maintains a stable posture without inclining, and the upper surface of the slab cast 101 and the box-shaped A spacer 301 is preferably provided in order to ensure a certain distance from the upper surface of the substrate.

  The length of the slab cast 1 loaded on the cart 4 is about 9 to 10 m. Therefore, the length of the slab longitudinal direction of the heat insulating structural member 3 having a steel box shape covering the upper surface of the uppermost slab slab of the loaded slab is as close as possible to the above length of the slab slab 1. Is preferred. For this purpose, the box-shaped heat insulating structural member 3 has an integral structure having a long length in the longitudinal direction of the slab cast piece 1 or is divided into, for example, a box-shaped structure having a length of about 1 m, What is necessary is just to comprise and connect these two or more.

  When a plurality of divided steel box-type structures are connected to form a heat-insulating structural member, the length per box-type structure is short, making it easy and making it aging Accordingly, there is an advantage that the box-type structures can be exchanged one by one. Further, the steel box-type structure is made of a stainless steel plate having a thickness of about 1 to 3 mm in consideration of heat insulation performance, heat resistance and mass per piece, and a vertical depth of 10 to 100 mm. It is preferable that Here, when the depth in the vertical direction is as shallow as about 10 mm, even if the side plate of the box-type structure is omitted, the amount of heat dissipation from the side surface is small, so the same effect as described above can be obtained. .

4). Covering ratio of the upper surface of the slab slab with the heat insulating structural member When covering the upper surface of the slab slab with either a glass wool or box-shaped heat insulating structural member, the heat dissipating area from the upper surface of the slab is reduced to enhance the heat retaining effect. Thus, warping of the slab can be effectively prevented. Considering the heat retention effect and economic efficiency in the actual equipment, it is preferable to cover 85% or more in the width direction of the slab and 65% or more in the longitudinal direction with the heat insulating structural member, so that a high heat retention effect can be obtained. From the viewpoint of eliminating slab warpage, it is more preferable to cover 90% or more of the slab width direction and 70% or more of the slab width direction with a heat insulating structural member.

  In order to confirm the effect of the cooling device for the laminated high-temperature slab cast piece according to the present invention, the test described below was performed and the result was evaluated.

  Table 1 shows test conditions and test results.

  As shown in the same table, as the test conditions, the initial surface temperature of the slab, the water spray pattern, the water spray amount, the heat retention treatment on the upper surface of the uppermost slab, etc. were changed, and the amount of warpage of the slab and the number of days required for cooling were investigated.

(1) Test method A low-carbon steel slab was cast by continuous casting, and the resulting high-temperature slab having a thickness of 227 mm, a width of 1250 mm, and a length of 9 m and an initial surface temperature of 700 to 760 ° C was obtained. A cooling test was performed in which water was sprayed on the side surfaces of nine (9 steps) stacked slabs. For water spray cooling, a full cone type nozzle arranged in one or more rows was used, and water was sprayed on the surface of the slab until the surface temperature of the upper surface of the slab or the side surface of the laminated slab decreased to a predetermined temperature.

  “Sprinkling pattern” described in Table 1 indicates the distinction between continuous water spray cooling or intermittent water spray cooling, and A, B, and C in the water spray pattern indicate water spray time, water spray stop time, and total water spray cooling time, respectively. To express. In addition, the watering pattern described in the table is an example of the watering cooling pattern using the watering cooling device of the present invention, and the present invention is not limited to this.

  In FIG. 10, the conceptual diagram of the time-dependent change of the watering amount in the watering cooling method is shown. In intermittent sprinkling cooling during the cooling test, the sprinkling time (A), sprinkling stop time (B) and total sprinkling cooling time (C) from the start of sprinkling cooling to the end of sprinkling cooling shown in FIG. Each value of A, B, and C shown was adopted and tested.

  In addition, “average watering amount” described in the table is (total watering amount (L) sprayed within the total watering cooling time) / (time from the start of watering cooling to the end of watering cooling (min)) / (cooling The value calculated by the total mass (t) of the slab.

  The “top slab heat treatment” in the table indicates the presence or absence of a heat treatment, and the notation “present” indicates a width of 1 m, a length of 1 m, and a depth of 100 mm as a heat treatment on the upper surface of the slab. This means that heat insulation was performed by placing a heat insulating structural member composed of eight box-shaped structures connected to the upper surface of the slab, and “None” indicates any treatment. Indicates that it was not done. Although not shown in the test results, similar results were obtained when a heat insulating structure having a depth of 10 mm (no side plate) was used.

  After sprinkling cooling, it was allowed to cool until the surface temperature of the slab became 40 ° C. or less, and the “warping amount” was measured. The measurement of the amount of warpage is performed by measuring the vertical gap between the uppermost slab and the lower slab, and converted to the amount of warpage (mm) per unit length (m) in the longitudinal direction of the slab, Displayed this.

  “Cooling days” is indicated by the required days from the end of continuous casting until the surface temperature of the slab drops to 40 ° C. The cooling days include air cooling after sprinkling cooling.

  Moreover, the surface temperature of the slab was measured as follows. Regarding the surface temperature of one slab, the surface temperature was measured at the center of one side surface in the longitudinal direction of the slab, and this was used as the surface temperature. Moreover, about the surface temperature of the laminated | stacked slab, the surface temperature in the center part of the one-side side surface of the longitudinal direction of the 5th slab from the bottom of the laminated slab was measured, and this was made into surface temperature. In addition, the surface temperature before watering was measured with the radiation type thermometer, and the surface temperature after watering was measured with the contact-type thermometer after drying the surface.

(2) Test results Test numbers 1 and 3 are tests for comparative examples that do not satisfy the requirements defined in the present invention. Among them, test number 1 is a test in which the sprinkler cooling device of the present invention is not used, and therefore, continuous sprinkling cooling is performed without performing heat insulation treatment of the uppermost slab, and test number 3 is heat insulation treatment of the uppermost slab. This is a test in which intermittent sprinkling cooling is performed without performing the above. On the other hand, test numbers 2, 4 and 5 are tests on the present invention examples that satisfy the requirements defined in the present invention.

  In the test numbers 1 and 3 of the comparative examples, the amount of warpage is larger than that of the inventive example. In test number 3 of the comparative example in which only the intermittent sprinkling cooling was performed without performing the heat treatment of the uppermost slab, the warping amount was reduced as compared with test number 1 in which continuous sprinkling cooling was performed, but there was no warping amount. It was not possible.

  Compared with test number 1 of the comparative example in which continuous water spray cooling was performed, test number 2 of the present invention example in which the water cooling device of the present invention was used for continuous cooling and the heat treatment of the uppermost slab was performed was The amount of warpage was reduced, and the effect of using the apparatus of the present invention was exhibited. Furthermore, in the test numbers 4 and 5 of the present invention example in which intermittent sprinkling cooling was performed using the sprinkling cooling apparatus of the present invention and the heat treatment of the uppermost slab was performed, extremely good results with no warpage were obtained. It was.

  The water spray cooling device of the present invention water-cools the side surfaces of the laminated high-temperature slab slabs and keeps the upper surface of the uppermost slab with a heat insulating structure under good operability, thereby improving productivity. It is a water spray cooling device that can prevent the occurrence of warpage of a slab and efficiently cool a slab without causing a decrease or an increase in cost. Therefore, the slab slab cooling device of the present invention is a simple sprinkling cooling device that can be stably operated over a long period of time without causing any trouble in the slab slab cooling process under high heat and steam atmosphere. As a broad application.

FIG. 1 is a diagram schematically showing a warpage generation process in laminated slab cast pieces, in which FIG. 1 (a) shows a state immediately after the start of water spray cooling, and FIG. The state in which the uppermost slab has warped, (c) in the same figure shows the state in which the uppermost slab has returned to the horizontal state, and (d) in FIG. And the state of progress. It is a figure which shows the method of the basic test regarding prevention of the curvature of the laminated slab cast slab, The figure (a) shows the case where the upper surface of the uppermost slab is covered with glass wool, The figure (b) shows the uppermost stage. The case where the upper surface of the slab is covered with a box-shaped heat insulating structural member made of a steel plate, and FIG. 7C shows a perspective view of the box-shaped heat insulating structural member made of a steel plate. The side view of the sprinkling cooling device of the laminated slab cast pieces is shown, in which FIG. (A) shows the state where the heat insulating structural member is lowered and placed on the upper surface of the uppermost slab, and FIG. Represents a state in which is lifted and removed from the upper surface of the uppermost slab. The front view (arrow A direction arrow in FIG. 3) of the sprinkling cooling device of the laminated slab slabs is shown, and the heat-insulating structural member is lowered and placed on the upper surface of the uppermost slab and the heat-insulating structural member is removed from the upper surface. In addition, it shows the watering condition on the side of the slab slab. It is a partial detail drawing which shows the connection state of a winding drum, a wire, and a heat insulation structural member, The figure (a) is a top view (B direction arrow in FIG. 4), The figure (b) is a side view ( (C direction arrow in FIG. 4). It is a side view which shows an example of the raising / lowering drive part of a heat insulation structure member (C direction arrow in FIG. 4). It is another partial detail drawing which shows the connection condition of a winding drum, a wire, and a heat insulation structural member, The figure (a) is a top view (B direction arrow in FIG. 4), The figure (b) is a side surface. The figure (C direction arrow view in FIG. 4) is represented. It is a figure which shows the example of the heat insulation structural member which wrapped glass wool with the reinforcing material. It is a figure which shows the state which covered the upper surface of the uppermost stage slab cast piece with the box-shaped heat insulation structural member, The figure (a) represents a top view, The figure (b) represents a side view. It is a conceptual diagram of the time-dependent change of the watering amount in watering cooling.

Explanation of symbols

1: slab slab, 101: top slab slab, 2: glass wool,
201: Reinforcing member, 3: Box-shaped heat insulating structural member, 301: Spacer,
302: Air layer, 4: Cart, 5: Winding drum, 6: Thermal insulation structural member,
7: Steel wire, 8: Winding shaft, 9: Chain,
10: Watering nozzle (watering spray device), 11: Lifting drive unit, 111: Cylinder, 112: Link mechanism, 113: Link fulcrum, 12: Heat insulation plate, 13: Motor

Claims (5)

A sprinkling cooling device for laminated high temperature slab slabs after casting,
A water spray apparatus for water cooling the both sides in the longitudinal direction of the laminated high temperature slab slabs;
A sprinkling and cooling device for laminated high-temperature slab slabs, comprising: a heat insulating structural member that covers an upper surface of the slab slab located at the uppermost stage of the laminated high-temperature slab slabs.   2. The laminated high-temperature slab according to claim 1, wherein the heat insulating structural member is installed so as to be movable up and down above an upper surface of the slab slab located at the uppermost stage of the laminated high-temperature slab slab. Sprinkler cooling device for slabs.   3. The heat insulating structural member can be moved up and down by winding or rewinding a steel wire or chain for suspending the member attached to the member around a drum. Sprinkling cooling device for laminated high temperature slab slabs.   The heat insulating structural member has a box shape covering the upper surface of the uppermost slab slab, and is configured by a steel box structure having an open bottom surface of the box shape and a space inside. The sprinkling cooling device for laminated high-temperature slab slabs according to any one of claims 1 to 3.   The heat insulating structural member is characterized in that the steel box-shaped structure forms an integral structure in the longitudinal direction of the high-temperature slab slab, or a box-shaped structure divided into two or more pieces is connected. The sprinkling cooling device for laminated high-temperature slab slab according to claim 4.

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