JPS61135422A - Hot straightening device of two layered clad metal plate - Google Patents

Abstract

PURPOSE:To prevent a metal plate from warping at room temperature by installing shields against cooling water between a cooling header and a passing region of the metal plate and by making the shields move in the lateral direction of the metal plate front-to-back. CONSTITUTION:Several leveller rollers 17A and 17B each, a top and bottom cooling headers 18A ad 18B are installed in a housing 10A of a hot straightening device 10. Masking guides 22A and 22B are set at both ends of the housing 10A and in positions below and above the rollers 17, respectively. The shields 25A and 25B linked with rollers 23 are set in the masking guides 22A and 22B, respectively. The top of the shields 25A and 25B are connected with the top of piston rods of driving cylinder devices 26A and 26B, respectively. By the connection, the shields 25A and 25B can move in the lateral direction of the plate 12 front-to-back. The mechanism performs accurate adjustment of cooling water of the cooling headers 18A and 18B and prevents the metal plate 12 from warping at room temperature.

Description

[Detailed description of the invention]

[Industrial Field of Application] The present invention relates to a hot straightening device for two-layer clad metal plates.

[Conventional technology]

Generally, in the rolling of thick plates, warpage produced in a finish rolling mill is hot straightened using a hot repeller, and then warpage produced on a cooling table is further cooled and cold straightened using a propeller. By the way, as shown in Fig. 1O, in the manufacturing process of a two-layer clad metal plate 1 such as a two-layer clad steel plate made of a base material IA and a laminated material IB, the coefficient of linear expansion of the base material IA and the laminated material IB is Due to the difference, as the temperature of the metal plate suddenly decreases after the end of rolling, large warpage occurs in both the width direction and the longitudinal direction of the metal plate 1 as shown in FIG. 11. metal plate l
The amount of warpage that occurs depends on the materials, plate thickness, plate width, and craft ratio of the base material IA and the mating material IH, but for example, when the base material IA is low carbon steel and the mating material IB is austenitic stainless steel, stainless steel There may be a concave shape on the side with a depth of 300 = 400 mm. In other words, in the case of a two-layer raft metal sheet, even if it is straightened with a leveler at 400 to 500°C at the end of rolling, warping due to the temperature difference occurs from the straightening end temperature to room temperature. occurs again, significantly impairing handling on table rollers. In addition, when the two-layer clad metal plate 1 is finished rolling, if the temperature of the metal plate 1 is lowered as much as possible by repeating straightening with the rolling mill while cooling with a mill descaling shower, the handling property on the table roller will be improved. However, the rolling efficiency is significantly reduced. In this case as well, when the metal plate 1 reaches room temperature, it will warp again. In addition, in the case of the two-layer raft metal plate 1, even during cold straightening, it is necessary to straighten the warp to a greater extent than in a normal metal plate, and the time required for straightening is long, resulting in poor productivity. Therefore, the present applicant has already published Japanese Patent Application Laid-Open No. 511-4212
In step 2, the metal with a large amount of thermal contraction located on the upper surface side of the metal plate in the hot straightening machine is forcibly cooled by the cooling water jetted by the cooling header to create a temperature difference that suppresses the occurrence of warping of the metal plate at room temperature. We have proposed a hot straightening device that is applied between the base material and the laminated material. According to the above-mentioned hot straightening apparatus, the metal plate is hot-straightened under conditions such that the metal plate after rolling has the same amount of warpage as after cooling to room temperature, and the warpage of the metal plate after cooling to room temperature is reduced. It can be suppressed. Namely. In this case, the metal plate will warp in the opposite direction (reverse warp) due to the scorching heat immediately after hot straightening, but there will be a difference in the amount of thermal contraction between the base material and the laminated material during subsequent cooling. This reduces the above-mentioned reverse warpage, making it possible to obtain a metal plate that is substantially flat at room temperature. [Problem to be Solved by the Invention J] However, in the hot straightening apparatus already proposed above, the cooling header simply removes the metal with a large amount of heat shrinkage located on the upper surface side of the two-layer kraft metal plate. Since it is a cooling device, the cooling water spouted from the cooling water flows from the top side of the metal plate to the bottom side, cooling the metal on the bottom side of the metal plate, and creating a predetermined gap between the base material and the laminated material. There are difficulties in providing temperature differences. In this way, if a predetermined temperature difference is not provided between the base material and the laminated material of the two-layer clad metal plate, there will be insufficient reverse warpage immediately after hot straightening, and the warpage of the metal plate at room temperature will be sufficiently suppressed. Otherwise, it is not appropriate because a complicated strain state occurs due to non-uniform cooling within the metal plate. An object of the present invention is to reliably provide a temperature difference effective for straightening warp between the base material and the laminated material of a two-layer clad metal plate, and to reliably suppress the occurrence of warp in the metal plate at room temperature. do. [Means for Solving the Problems 1] The present invention provides a cooling method in which cooling water is jetted in the width direction of the passing area of the metal plate in a hot straightening machine for a two-layer clad metal plate made of a base material and a laminated material. 2. A header is used to forcibly cool the metal side of the metal plate that has a large amount of thermal contraction, and a temperature difference is created between the base material and the laminated material to suppress the occurrence of warping of the metal plate at room temperature. In the hot straightening apparatus for clad metal plates, a shielding plate is provided between the cooling header and the metal plate passing area to shield the cooling water spouted from the cooling header from the said plate passing area, and the shielding plate driving means The shielding plate can be moved forward and backward in the width direction of the L plate passing area. [Function] According to the present invention, by setting the shielding plate at the optimum position corresponding to the width of the two-layer clad metal plate, the cooling can be carried out smoothly.
The jetted cooling water reliably cools only the metal surface that corresponds to the blower, and reliably provides a temperature difference between the base material of the metal plate and the laminated material that is effective for straightening the warp. It becomes possible to reliably suppress the occurrence of warpage of the board at room temperature. [Example] Fig. 9 is a layout diagram showing a production line for two-layer clad steel sheets to which the invention is applied; The figure is a sectional view taken along the line ■-■ in Figure 1, Figure 3 is a front view showing the main parts of Figure 1, Figure 4 is a plan view of Figure 3, and Figure 5 is the main part of Figure 3. A front view showing an enlarged section of the t! Figure lS6 is a plan view of the fifth factor. In FIG. 9, reference numeral 11 denotes a rolling mill, and a thermometer 13 is installed on the exit side of the rolling mill 11 to measure the temperature of the two-layer clad steel plate 12 rolled by the rolling mill 11. On the entry side of the hot straightening device 10, there is a steel plate detector (hot lump detector) 14 that detects the steel plate 12 entering the hot straightening device IO.
A. A thermometer 15 is installed to detect the temperature of the steel plate 12. Further, on the exit side of the hot straightening device IO, there is a steel plate detector 14B that detects the steel plate 12 entering the hot straightening device IO again from the exit side of the hot straightening device 10 during multi-pass straightening.
The temperature of the steel plate 12 located on the exit side of the hot straightening device 10 is
A thermometer 16 for detection is installed. The hot straightening device 10 has a leveler roll 17 inside the housing IOA that flattens the steel plate 12 under plastic deformation by repeatedly bending the steel plate 12. The leveler roll 17 includes a plurality of lower rollers 17A,
It consists of a plurality of upper rollers 17B. Further, in the hot straightening apparatus IO, a lower cooling header 18A is disposed between each of the lower rollers 17A, and a main cooling header 18B is installed between each of the upper rollers 17B. Each cooling header 18A, 18B has slit nozzles 19A, 1 that spout cooling water in the width direction of the passing area of the steel plate 12.
It is equipped with 9B. In addition, each lower cooling header 18A is
An electromagnetic on-off valve 21A is interposed in each of the water supply channels that are collectively connected to the lower water supply header 2OA and formed between each lower cooling header 18A and the lower water supply header 2OA. In addition, each main cooling header 18B is connected to the main water supply header 2.
An electromagnetic on-off valve 21B is installed in each of the water supply channels that are collectively connected to the main cooling water supply header 18B and the main water supply header 20B. In addition, the hot straightening device 10 includes left and right lower masking guides 22A, and left and right upper masking guides at the lower and upper portions on both sides of the leveler roll 17 on the inner surface of the housing IOA in the vicinity of the entrance and exit sides thereof. Each of the guides 22B is metered. Each of the masking guides 22A, 22B rotatably accommodates a large number of rollers 23 connected in a chain, and each pin 24 located at the center of rotation of each roller 23 has both ends of the lower masking plate 25A. and both ends of the upper masking plate 25B are connected to each other. That is, each of the lower masking plates 25A is connected in a chain in which the mutually contacting ends are overlapped, and is located between the lower cooling header 18A and the passing area of the steel plate 12 in a state where cooling water can be cut off. The lower cooling header 18A forms a shielding plate of the present invention that can shield the jetted cooling water from the plate passing area. In addition, each of the above upper masking plates 25B
The main cooling headers 18B are also connected in a chain with their mutually contacting ends overlapping, and are located between the main cooling header 18B and the plate passing area of the steel plate 12 in a state where cooling water can be cut off.
8B forms the shielding plate of the present invention that shields the cooling water spouted from the plate passing area. Here, the piston rod tip of the lower drive cylinder device 28A is coupled to the tip of the left and right chain-shaped lower masking plates 25A located near the entrance and exit sides of the hot straightening device 10, The left and right chain-like upper masking plates 25
A piston rod tip of the main drive cylinder device 26B is coupled to the tip of B. That is, the drive cylinder devices 26A and 26B form the shielding plate drive means of the present invention, and move the masking plates 25A and 25B back and forth in the width direction of the passing area of the steel plate 12, and move their tips. It can be set at an optimal position corresponding to the width of the steel plate 12. Next, the operation of the above embodiment will be explained. In this embodiment, the hot straightening device IO is capable of straightening the steel plate 12 in multiple passes for reasons described later, and in the initial straightening stage (for example, the first pass) of the steel plate 12, the amount of heat shrinkage of the steel plate 12 is reduced. Cooling headers 18A, 18B for large metals, for example 7 to lower cooling in this embodiment
Only the cooling header 18A side is operated, and after the initial straightening stage of the steel plate 12 has passed, both cooling headers 18A and 18B can be operated. The temperature of the steel plate 12 after rolling by the rolling mill 11 is measured by the thermometer 13.
Once the temperature is constant, a process computer or the like calculates the amount of cooling water and threading speed (cooling time) for each cooling header 18A, 18B according to the measured temperature, material of the steel plate 12, width, thickness, and cladding ratio. be instructed. The above-mentioned cooling water amount and sheet threading speed are checked again based on the temperature measurement result of the steel plate 12 by the thermometer 15 installed on the entry side of the hot straightening device 10. The hot straightening apparatus 10 allows the calculated amount of cooling water to be set by adjusting the electromagnetic on-off valves 21A and 21B, and the calculated sheet threading speed to be set by adjusting the feeding speed of the table roll. There is. As a result, after the hot straightening device 10 detects the tip of the steel plate 12 with the steel plate detector 14A, a timer or the like is used to electromagnetically open/close each cooling header 18A, 18B arranged adjacently in the passing direction of the steel plate 12. Valve 21A, 2
1B are sequentially opened in response to the passage of the tip of the steel plate 12, and the metal surfaces of the steel plate 12 corresponding to the respective cooling headers 18A and 18B are cooled. In addition, after the hot straightening device 1O detects the rear end of the steel plate 12 with the steel plate detector 14A, the electromagnetic opening/closing of each cooling header j8A, 18B arranged adjacent to each other in the threading direction of the steel plate 12 is performed using a timer or the like. valve 21
A and 21B are sequentially closed in response to passage of the rear end of the steel plate 12. Note that the hot straightening device 10 performs hot straightening from the exit side of the hot straightening device 10 when straightening the steel plate 12 in multiple passes. 1
The rear end of the steel plate 12'' that re-enters the steel plate 110 is detected by the steel plate detector 1.
4B, and controls the opening and closing of the electromagnetic on-off valves 21A and 21B of each cooling header 18A and 18B in the same manner as described above. Further, when the temperature of the steel plate 12 after straightening in the hot straightening device 1G is measured by the thermometer 16, the amount of warpage of the steel plate 12 that will occur at room temperature is predicted by a process computer, etc., and the process computer etc. Using this preliminary value, the calculation of the amount of cooling water per sheet passing speed of each cooling header 18A, 1811 necessary for straightening the next material is corrected. Therefore, in the hot straightening device IO, the steel plate 12
The masking plates 25A and 25B are moved forward and backward in the width direction of the passing area of the steel plate 12 by operating the drive cylinder devices 26A and 26B according to the width of the steel plate 12, and the masking plates The tips of 25A and 25B are set at optimal positions corresponding to the width of the steel plate 12. As a result, the first part of the steel plate 12 in the hot straightening device 10
In the path, the cooling water jets out from the slit nozzle 19A of the lower cooling header 18A. Only the metal side of the corresponding steel plate 12 with a large amount of thermal contraction is reliably cooled, and there is no change in the temperature state of the metal on the opposite side. The temperature difference necessary to suppress the occurrence of warping at room temperature is reliably applied to the steel plate 12, and the hot straightening device 10 stretches the metal in a state that cancels out the thermal contraction of the metal, which has a large amount of thermal contraction. Both metals are straightened into the same shape under a condition where a certain temperature difference is applied to both metals. Further, the hot straightening device 10 performs upper and lower pre-cooling during straightening of the steel plate 12 in the second pass and subsequent passes following single-sided cooling in the first pass.
, 18B, each slit nozzle 19A, 1911,
An appropriate amount of cooling water is supplied only to the base metal side or the laminated metal side of the steel plate 12 corresponding thereto, and the steel plate 12 is quickly brought to room temperature, making it possible to make a flat plate. In addition, in the hot straightening device 10, multiple-pass straightening is performed to lower cooling, consisting of a first pass by operating only the header 18A, and a second pass and subsequent passes by operating the upper and lower pre-cooling headers 18A and 18B. The reason for adopting this method is as follows. That is, the steel plate 1 obtained by the first pass is
In the single-sided cooling described in 2, in principle, after the cooled steel plate 12 is reversely warped, the temperature at the end of cooling (for example, about 300 m2 for a thin steel plate with a thickness of 8 to 12 m ℃, about 400 for a thick steel plate with a plate thickness of 20 to 25■■
C) until it reaches room temperature, distortion occurs again, and the above-mentioned reverse warp of the steel plate 12 can be flattened. However, since the inlet temperature, outlet temperature, plate thickness, plate width, cladding ratio, etc. of the steel plate 12 are mostly different for each sheet, the amount of cooling water and the threading speed are controlled according to changes in these conditions. However, it is quite difficult to manufacture a plate that does not require straightening at room temperature (for example, if there are temperature deviations inside the steel plate, some parts cool well and some parts do not cool even with single-sided cooling,
In addition, the conveyance path of the board after cooling on one side (that is, there is a difference between the board placed on the table roll for a long time and the board placed quickly on the dirt floor), there will be a slight distortion of either upward or downward warping at room temperature. , these plates require cold straightening (cold leveling). In order to omit this cold straightening step, it is preferable to cool the steel plate 12 from the upper and lower surfaces to quickly bring it to room temperature after cooling one side, as in the multiple pass straightening using the hot straightening device IO described above. becomes. That is, according to the experimental results of the present inventor, the temperature of the steel plate 12 decreases by 100-150°C in one pass of cooling on one side, and the temperature of the steel plate 12 decreases by 100-150°C.
The temperature is usually around 550°C to 400°C. Therefore,
In order to bring the steel plate 12 to room temperature, since the steel plate 12 is in the most efficient temperature range in the nucleate boiling region by water cooling, after the single side cooling, two to three passes of upper and lower side cooling are performed. It is possible to quickly bring the steel plate 12 to room temperature. FIG. 7 is a front view showing a modification of the embodiment shown in FIGS. 1 to 6, and FIG. 8 is a cross-sectional view taken along the line ■--■ in FIG. 7. This hot straightening device 30 differs from the hot straightening device 1O in that it has a main cooling header 18B, an upper masking plate 25B,
The only difference is that the upper drive cylinder device 26B has been removed. In other words, this hot straightening device! 130 performs single-sided cooling on the metal side of the steel plate 12 which has a large amount of thermal contraction by the operation of the lower cooling header 18A, and by using the lower masking plate 25A and the lower drive cylinder device 26A, As in the hot straightening apparatus IO, the cooling water spouted from the lower cooling header 18A is transferred to the lower cooling header 18A.
Only the lower surface side of the steel plate 12 corresponding to the above can be reliably cooled. Therefore, although the steel plate 12 straightened by the hot straightening device 30 is reversely warped after the straightening due to recuperation due to the heat content of the uncooled metal side, the reverse warp flattens out by the time it reaches room temperature. In addition, in implementing the present invention, if the masking of the metal plate passing area by the shielding plate is excessive (cooling an area smaller than the width of the metal plate), a part that cannot be reversely warped is added to the edge of the metal plate. Therefore, the setting of this masking area needs to be done minutely. [Effects of the Invention] As described above, the present invention provides a cooling method in which cooling water is spouted in the width direction of the passing area of the metal plate in a hot straightening machine for a two-layer clad metal plate made of a base material and a laminated material. A two-layer structure that uses a header to forcibly cool the metal side of the metal plate that has a large amount of thermal contraction, and provides a temperature difference between the base material and the laminated material that suppresses the occurrence of warping of the metal plate at room temperature. In the hot straightening apparatus for clad metal plates, a shielding plate is provided between the cooling header and the metal plate passing area to shield the cooling water spouted by the cooling header from the said plate passing area, and the shielding plate driving means The shielding plate is configured as a cylinder 11 that moves forward and backward in the width direction of the plate passing area. Therefore, 2M! It is possible to reliably provide a temperature difference effective for straightening warp between the base material of the clad metal plate and the laminated material, and to reliably suppress the occurrence of warp in the metal plate at room temperature.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a hot straightening device 10 according to an embodiment of the present invention, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. 3 shows the main parts of FIG. 1. 4 is a plan view of FIG. 3, FIG. 5 is an enlarged front view of the main part of FIG. 3, FIG. 6 is a plan view of FIG. 5, and FIG. 7 is a plan view of the present invention. FIG. 8 is a front view showing a modification of FIG. 7, and FIG.
The figure is a measurement diagram showing a production line for a two-layer clad metal plate, the 1θ figure is a cross-sectional view showing a 2M clad metal plate, and the figure 11 is a cross-sectional view showing a state in which warpage occurs in a two-layer clad metal plate. 1...2-layer craft metal plate, IA...base material, 1B...
...Laminated material, 1G...Hot straightening device. 12...Two-layer clad steel plate, 17...Leveler roll, 18A, 18B...Cooling header, 25A, 25B...Masking plate, 26A, 26B...Drive cylinder device, 30...Hot Orthodontic device. Agent Patent Attorney Osamu Shiokawa Figure 1 n Figure 2 Figure 3 Figure 5

Claims (1)

[Claims] (1) A cooling header that sprays cooling water in the width direction of the passing area of the metal plate is installed in a hot straightening machine for a two-layer clad metal plate consisting of a base material and a laminated material. A hot straightening device for two-layer clad metal plates that forcibly cools the metal side with a large amount of shrinkage and provides a temperature difference between the base material and the laminated material that suppresses the occurrence of warping of the metal plate at room temperature. A shielding plate is provided between the header and the metal plate passing area to shield the cooling water spouted by the cooling header from the plate passing area, and a shielding plate driving means moves the shielding plate in the width direction of the plate passing area. A hot straightening device for a two-layer clad metal plate, which is capable of moving forward and backward.