JPS623384Y2 - - Google Patents

Description

[Detailed Description of the Invention] ``Purpose of the Invention'' The present invention relates to an aluminum strip cooling device, and is capable of efficiently cooling aluminum strips by using compact equipment for quenching, etc.
Moreover, it is possible to obtain an aluminum strip with good surface quality.

Industrial applications Continuous cooling equipment for aluminum strips.

Prior Art In order to impart a hardening effect to an aluminum strip continuously rolled by a rolling mill, it is necessary to heat it to a required temperature and then rapidly cool it with a cooling liquid. In such cooling equipment, it is common to run the aluminum strip horizontally to heat it and then cool it.

On the other hand, since horizontal running requires a large area of equipment, the strip is run vertically, with a large number of nozzles arranged in a row in the width direction of the strip, and coolant is injected from these nozzles. In some cases, quenching is also carried out.

Problems to be solved by the invention However, each of the conventional methods described above has its own problems. That is, in the case where the strip runs horizontally, the equipment must be very large. This disadvantage can be avoided by running the strip vertically, but in a device that runs the strip vertically, the cooling liquid is discharged from a number of nozzles arranged in a row as described above to rapidly cool the strip. In some cases, especially when the thickness of the strip is less than 4 mm, the thickness of the rapidly cooled strip becomes uneven, which affects the brightness of the surface of the plate, especially when anodized, making it impossible to obtain a desirable product. .

``Structure of the invention'' Means for solving the problem The strip has a running means for moving the heated aluminum strip in the vertical direction, and a coolant is discharged onto the surface of the strip that is moved by the running means. This is an aluminum strip cooling device, characterized in that it is equipped with a nozzle means for cooling the aluminum strip, and a mesh means is provided between the nozzle means and the strip surface to make the coolant particles finely discharged.

Function The cooling liquid droplets ejected from the nozzle toward the strip are finely rectified by the mesh means and supplied to the strip surface, and the non-uniformity of the flow rate distribution at the boundary of the liquid ejected from the nozzle is alleviated and the cooling liquid particles are This eliminates or reduces the occurrence of thermal stress differences in the process, resulting in a preferable quenched product with a small difference in plate thickness.

Embodiment To explain the specific embodiment of the present invention shown in the attached drawings, the general structural relationship of the equipment is as shown in FIG.
1, 11... pass vertically into the heating zone 12 and the cooling zone 1, which is the same as in the conventional vertical strip running system described above, but in the present invention, this method is used. In the cooling zone 1, the structural relationship with respect to the strip 10 is as summarized in FIG.

That is, a nozzle 2 is provided for discharging the cooling liquid onto the surface of the strip 10 as described above.
A mesh means 3 is provided between the nozzle 2 and the strip 10 to make the cooling liquid particles finer. An appropriate nozzle may be adopted in consideration, but according to the results of many practical studies by the present inventors, the number of nozzles is preferably one or as small as possible, and the mesh of the mesh means 3 is preferably 100 mesh or more. It is preferable to set it to about 5 meshes.

In other words, the results of detailed observation and study of the situation in which a large number of nozzles are arranged in the width direction in the conventional type described above, which result in strips with unfavorable surface texture due to uneven board thickness, show that variations between nozzles are observed. It is recognized that this is occurring. In other words, uneven flow distribution of ejected liquid inevitably occurs between one nozzle and the adjacent nozzle, which causes a thermal stress difference corresponding to the nozzle spacing in the plate width direction, resulting in As a result, a plate thickness variation portion occurs depending on the number of thermal stress difference portions. Therefore, it is preferable to reduce the number of such thermal stress difference areas (plate thickness variation areas) as much as possible, and ideally the entire plate width should be covered by a single nozzle. If the number of nozzles is sufficiently reduced, results similar to those obtained with a single nozzle can be obtained. If the nozzle capacity (flow rate: /min) becomes large, the diameter of the water droplets ejected from the nozzle will be large and the flight direction of the water droplets will become unstable, which is inappropriate, so the diameter of the water droplets should be 200μmφ or less. is preferable,
Such water droplets can be appropriately obtained by passing through the mesh means 3 as described above.

The mesh means 3 described above may be linear in plan or arcuate in plan as shown in FIG. 2A, and linear in vertical section as shown in FIG. 2B. This is particularly preferred when the nozzle 2 is a single nozzle, and is arranged symmetrically on both sides of the strip 10, as shown in FIG. However, in the case where a plurality of nozzles 2 are used, the mesh means 3 is used as a straight line in a plane as shown in FIG. Note that the water droplet flow ejected from the strip 10 and the nozzle 2 at an angle α is such that the distance ratio d ₂ /d 1 between the mesh means 10 and the mesh means 3 and between the mesh means 3 and the nozzle ₂ is 1/5<d. ₂ /d ₁ <10, but the ratio D/ _{d 2} of the radius of curvature D of the mesh means 3 and the distance between the mesh means 3 and the nozzle 2 is 0.2 or more;
The ratio/W between the width of the aluminum strip and the width of the water droplet ejected from the nozzle 2 at the position of the strip is 0.8 or less, and the mesh means 3
Preferably, the mounting angle is 45 to 90 degrees with respect to the longitudinal direction of the aluminum strip.

The water droplets ejected from the nozzle 2 at an angle α pass through the mesh means 3, and the particle size becomes smaller.
The spray angle is also generally expanded. Moreover, the water droplets that have passed through the mesh are appropriately made fine and sized, and as a result, uniform cooling can be obtained. If the mesh size is 5 or more meshes, these effects will be poor, and if the mesh size is less than 100 meshes, it will be too fine and it will be difficult for water droplets to pass through. The mesh means may be made of metal, synthetic resin, or other materials as appropriate.

To explain a specific operation example of the device according to the present invention as described above, JISA1050 alloy is hot-rolled and cold-rolled using conventional methods to produce a material with a width of 1000 mm and a thickness of 1.5 mm.
mm aluminum strip, and this is the first
450℃ in heating zone 12 in the equipment shown in the figure.
and then in cooling zone 1 from nozzle 2 to
Water was injected at 120° C. and 200/min from the front and back sides of the strip 10, and the water droplets were cooled through a 15-mesh metal net 3 to make the water droplets fine.

The thickness of the aluminum strip in the width direction was measured using a contact scanning type thickness measuring device, and the variation in thickness, excluding the plate crown, was 0.3 μm before quenching, but it was 0.3 μm after quenching. No difference was observed between the two, and a desirable product was obtained.

On the other hand, when the mesh means is removed using the same equipment and cooled in the same manner as described above, the plate thickness variation excluding the plate crown is 2 to 3 μm, and the plate thickness variation is sufficiently reduced by the present invention. It was confirmed.

``Effects of the invention'' According to the invention as explained above, it is possible to achieve preferable cooling of aluminum strips for quenching and other purposes using compact equipment that allows the strips to run vertically, and moreover, it is possible to cool the aluminum strips by rapid cooling using water droplets. This is an industrially highly effective idea, as it produces fewer thermal stress differences in the aluminum strip and produces a product with favorable surface texture and plate structure.

[Brief explanation of the drawing]

The drawings show embodiments of the present invention; Fig. 1 is a side view showing an example of continuous heating and cooling equipment for aluminum strips employing the present invention;
The figures are planar and vertical sectional explanatory views of the spray state of the cooling mechanism according to the present invention, Fig. 3 is an explanatory view of the cooling relationship between the front and back sides of the strip, and Fig. 4
The figure is an explanatory plan view when a plurality of nozzles are used. However, in these drawings, 1 is a cooling zone, and 2 is a cooling zone.
3 is a nozzle, 3 is a mesh means, and 10 is an aluminum strip.

Claims (1)

[Scope of utility model registration request] It has a running means for running the heated aluminum strip in the vertical direction, and a nozzle means for discharging a cooling liquid onto the surface of the strip that is run by the running means, and furthermore, the nozzle means and the strip surface are connected to each other. 1. An aluminum strip cooling device characterized in that a mesh means is provided between the aluminum strip and the cooling liquid to make the coolant particles finer.