JPH0216993Y2 - - Google Patents

Description

[Detailed explanation of the idea]

(Industrial Application Field) The present invention involves forming a wire rod immediately after hot rolling into a continuous spiral ring shape using a winding machine, and sequentially placing the wire rod on a conveying device so that the center of the ring shape is It relates to a device that cools while continuously transferring the pitch in a shifted state. (Prior art) Since the hot-rolled wire rod has a temperature higher than the _A3 transformation point of steel, the hot-rolled wire rod is formed into a continuous spiral ring shape using the sensible heat. A method of controlling and cooling a wire rod formed in a shape using a fluid such as a gas, a liquid, or a gas-liquid mixture while transporting the wire rod on a conveying device (e.g., a conveyor) with the center of the ring shifted by a certain pitch; The so-called direct patenting method is known as a technology that has been adopted by those skilled in the art since around 1960, and the Stelmore process has been widely adopted among those skilled in the art, for example, as famous in Japanese Patent Publication No. 15463/1973. be. The direct patenting method, typified by the above-mentioned Stelmor process, involves, for example, forming a wire rod hot rolled in a finishing mill into a continuous ring shape in a winding machine while cooling it to about 800°C in a water cooling device. They are placed one after another on a conveying device that also serves as a cooling device, and are continuously transferred with their centers shifted by a certain pitch.
It blows a blast of air to provide controlled cooling. For this reason, in this system, when the cooling device (conveyor) is viewed from above, a wire consisting of a group of rings whose centers are shifted by a certain pitch is generated. Therefore, in the ring group, whether viewed in cross section in the width direction of the conveyor or viewed in plan, there are areas where the density is large or small depending on the degree of overlapping of the rings. In this state, as shown in a plan view in FIG. 7, there are many overlapping rings at both ends of the conveyor, and the density per unit area of the conveyor is also large.
[In the present invention, this is referred to as the dense line portion 3A]. On the other hand, near the center of the conveyor, as shown in FIG. 7, there is little ring overlap, and the density per unit area of the conveyor is low. [In the present invention, this is referred to as the coarse wire portion 3C]. Further, the area between the dense line part and the coarse line part is called an intermediate part 3B. Therefore, the cooling rate of the dense wire portion is slower than that of the coarse wire portion, and a difference in cooling rate occurs in the cross-sectional direction and the longitudinal direction of the wire ring. In addition, as shown in Fig. 2, the ring-shaped wire rod is held in a chain 5 that moves and is held on rails provided on the cooling bed.
Since the wire rings 3 are transported by the rail 4 and the chain 5, there are parts of the wire rings that are not directly affected by the cooling action of the fluid from the nozzles provided on the cooling bed 2. cross-sectional direction,
A difference in cooling rate occurs in the longitudinal direction. These differences in cooling rate cause the transformation start temperature, transformation end temperature, and time required for transformation to differ in each part of the wire ring, resulting in structural differences in each part of the wire, resulting in changes in mechanical properties such as tensile strength and reduction of area. Differences arise, and
Differences occur in properties such as scale thickness and composition,
This leaves problems in so-called quality control of wire rods. Due to the above-mentioned background, many proposals have been made in the past for the purpose of improving the quality of the wire by uniformly cooling the dense wire part, intermediate part, and coarse wire part, but among these, the technology closest to the present invention is is considered to be described in Japanese Patent Application Laid-Open No. 51-83043. (Problem that the invention aims to solve) The wire ring has different densities in the width direction of the cooling device and the degree of overlapping of the wires is different, so the center part of the wire ring is a dense part and the outer part is a dense part. . For this reason, the wind does not pass through particularly well on the outside, so the wire is not cooled uniformly. For this reason, there were variations in the tensile strength (T·S) within the wire ring. As mentioned above, the method to solve these problems is
As disclosed in Japanese Patent No. 51-83043, in this technique, the cooling nozzle blows cold air in the direction of the chain and rail portions. For this reason, a dead air zone (a location where the cooling fluid is difficult to directly act on the contact area between the wire ring and the conveying means) is formed in the chain portion, resulting in uneven cooling and less effectiveness. Based on the above, the purpose of the present invention is to provide a cooling device for hot rolled wire rods that achieves more uniform cooling of the wire rod than the conventional technology, improves the variation in tensile strength within the wire rod ring, and improves the quality of the wire rod. It provides: (Means and effects for solving the problem) The means for achieving the above object of this invention is to control the ejection amount or ejection speed of the cooling fluid according to the coarse line part and the intermediate line dense part, as explained below. It is effective to make the wire ring larger, the wire ring should not be conveyed in direct contact with the rail, and cooling fluid should be sprayed on the contact area of the wire ring that contacts the chain. The outer and inner circumferences are sprayed alternately at a spraying angle of 45° to 90°, and the cooling fluid is sprayed upward and parallel to the wire ring group conveying direction on the coarse wire portions and intermediate portions. It consists in spraying. That is, the configuration of the present invention is as follows. The wire rod after hot rolling is formed into a continuous spiral ring shape, and the wire rod formed into the ring shape is placed on a conveyor having a rail section and a chain section arranged on a cooling bed, and the center of the ring is In the apparatus for cooling the wire rod by fluid ejected from the cooling bed surface while transferring the wire rods while shifting the wire rods at a certain pitch, the chain rail section is divided in the length direction,
A chain part nozzle 8 that sprays cooling fluid upward from directly below the chain is provided at the divided interval to correspond to the wire dense part 3A that occurs in the group of wire rings that are transported by shifting the center by a certain pitch. A cooling bed device includes a line dense part nozzle group 10A that sprays cooling fluid from the outer circumferential direction of the ring, and a line dense part nozzle group 1 that sprays fluid from the inner circumferential direction of the ring.
0B are arranged alternately, and at a cooling position corresponding to the intermediate part 3B that occurs in the group of wire rod rings to be transported,
An intermediate nozzle 9 is provided upward in the same direction as the conveying direction of the chain section, and a nozzle 9 for the intermediate section is provided in the same direction as the conveying direction of the chain section at a cooling bed position corresponding to the wire rough portion 3C that occurs in the wire rod ring group to be conveyed. This cooling device for hot rolled wire is characterized in that a nozzle 7 for the rough portion of the wire is installed upward and parallel to each other. A specific example of the present invention will be described below based on the drawings. In FIG. 1, 1 is a raining head and 2 is a cooling bed, which are usually made of cast iron. The cooling bed 2 is divided into a plurality of parts in the longitudinal direction and is removable, and a chain conveyor 5 for conveying a group of wire rings 3 is provided on the cooling bed 2 directly above and in contact with a guide rail 6. . As shown in FIG. 2, the rail 6 is divided at predetermined locations in the longitudinal direction to provide intervals. The chain nozzle 8 is located between the guide rails 6 and directly below the chain conveyor 5, and is configured to spray cooling fluid upward.
Therefore, although not shown in the figure, the chain part nozzle 8 sprays the cooling fluid from the plenum chamber from directly below the chain conveyor 5 in the upward direction indicated by the arrow as shown in FIG. By passing through the gap and spraying it onto the wire ring group 3 placed directly above it, the dead wind zone (point where the cooling effect is poor because the cooling fluid is obstructed by chains, guide rails, etc.) is removed. It has the effect of suppressing the occurrence. This greatly contributes to promoting uniform cooling of the wire ring group 3. Moreover, the cooling fluid sprayed from the nozzle 8 has the effect of protecting the chain conveyor 5 from the sensible heat of the wire ring group and suppressing deformation and damage due to thermal strain, thereby improving the life of the equipment. The line dense area nozzles 10A and 10B are provided on both sides of the cooling bed 2, as shown in FIG. The cooling bed 2 is divided into a plurality of parts in the conveying direction of the wire ring group 3, and the wire dense part nozzles 10A, 10B are used to divide the wire rod ring group 3 into parts as shown in FIG. A nozzle group 10A that sprays cooling fluid from the outer circumferential direction and a nozzle group 10B that sprays cooling fluid from the inner circumferential direction of the wire ring group 3 are alternately provided. As described above, the wire dense part nozzles are provided with the nozzle groups 10A and 10B alternately, so for the wire rings forming the wire ring group 3, as shown in FIG. Spray alternately at a spray angle of 45° to 90°. Such a configuration effectively cools the wire at each position in the wire-dense portion, and exhibits the effect of uniformly cooling the wire-dense portion. As shown in FIG. 5, the wire rough portion nozzle 7 is configured to face upward and in the same direction as the conveying direction of the wire ring group 3. In this embodiment, the spraying direction angle θ of the cooling fluid is approximately 15° to 45°, and the nozzle 9 constituting the intermediate nozzle 9 also exhibits the same embodiment. (Example) Next, an example of the present invention will be described. A device for supplying blast air as a cooling fluid is not shown in the drawings;
°C) air via the plenum chamber,
Cold air of Nm ³ /H/one blower was blown from the nozzle at a jetting speed of 40 m/s. For example, if we look at the entire cooling bed 2 shown in Fig. 1 from a macroscopic perspective, a large river of blast winds is formed, creating an environment necessary for cooling, and in this environment only chain conveyors are used to transport wire rod rings. Although not shown, the intended cooling is performed while being conveyed toward the focusing tab at a speed of 0.3 m/s to 0.7 m/s. Chain part nozzle 8 is conveyed by the chain while conveying the wire ring group.
Since the wind is blown by the wind turbine, the dead wind zone is hardly generated and the area is cooled down. In addition, since the wire dense portion of the wire ring group 3 is cooled alternately from the wire dense portion nozzles 10A and 10B to the outer circumference and inner circumference of the wire ring, the dense wire portion nozzle according to the present invention is used for cooling. It is possible to achieve more uniform cooling than in the case of a method in which no wire rings are used, and variations in the mechanical properties of the wire ring group 3 can be improved. As a test material, a hard steel wire rod (5.5 mmφ) with the composition shown in Table 1 was blown with blast air at a flow rate of 40 m/sec in the dense wire area, and a comparison was made between the device of the present invention and the device of the present invention without using the dense wire nozzle. Examples were tested.

Table 2 also shows the tensile strength (Kg/mm ² ) and variation of the present invention and comparative examples (A to E).

[Table] These results are shown in the radar charts of tensile strength in FIGS. 8 to 13. The direction of the arrow indicates the direction in which the wire ring group 3 moves. Further, the distance in the radial direction of the regular octagon indicates the tensile strength, and depending on the variation in the wire ring, the tensile strength varies in the coarse wire part, the middle part, and the coarse wire part. indicates a coarse line part, a middle part, and a dense line part, respectively. FIG. 8 shows the result of alternately providing nozzles 10A and 10B, which form line-dense nozzles, in the apparatus of the present invention. As can be seen from this figure, when the device of the present invention is used, the variation in tensile strength is minimized and improved. On the other hand, Comparative Example A is an example in which only nozzle 10A is used to form the wire-dense nozzle, and as a result, the ring of wire ring group 3 blows blast air only from the inner circumferential direction, as shown in Fig. 9. There are parts with low tensile strength, which causes variations and poor quality.
As shown in the figure, this shows that the tensile strength is high, but the tensile strength is low. Comparative example B is an example in which only nozzle 10B is used to form the line-dense nozzle, and as a result, the rings of the preparation ring group are blown with blast air only from the outer circumferential direction, so the tensile strength is reduced as shown in Figure 10. There are some areas with low levels, which causes variations and impairs quality.
This is clear from the fact that the tensile strength in the figure is high, but the tensile strength is low. Comparative example C is an example in which a blast is blown onto the wire-dense part in the direction of movement and in the direction perpendicular to the direction of movement and from the outer circumferential direction, but as shown in Fig. 11, there is a large variation in tensile strength. quality is impaired. Comparative example D is an example in which a blast is blown against the wire dense portion in the traveling direction and from the inner circumferential direction at right angles to the traveling direction, but as shown in FIG. 12, variations in tensile strength occur. , harming the quality. This can also be seen from the large variation in . Comparative example E is an example in which a blast is blown onto the dense line part from the same direction as the traveling direction.
As shown in the figure, variations in tensile strength occur, impairing quality. As described above, in the device of the present invention, by alternately providing the nozzles 10A and nozzles 10B, which form the line-dense area nozzles, which has not been considered conventionally, there is a remarkable effect of uniformly cooling the line-dense area. The results are summarized in Table 2. In addition, the results of testing the degree of occurrence of dead wind zone are shown in the 14th
Shown in Figures A, B, and C. This figure shows an example used for testing to improve the dead wind zone of continuous rails guiding a chain conveyor. In the case of FIG. 14A, the wind is blown from an inclined direction toward the contact surface with the wire ring group 3 placed on the guide rail 10 and the guide chain 11.
Also, Figure B has the same configuration as Figure A, except that a part of the dead wind belt prevention nozzle is extended below the chain guide rail 10. Furthermore, in addition to the configuration of the dead wind zone prevention nozzle, C in the same figure is configured to be able to spray in parallel to the chain 11 and guide rail 10 and also in the conveying direction. However, in these cases, the area marked with an x in FIG. 14 becomes a dead wind zone, and it can be seen that changing the spray direction of the nozzle is not very effective. On the other hand, in the nozzle 8 for the chain guide rail section according to the present invention, which is shown enlarged in FIG. Since the configuration is such that blast air passes through the gap between the chain conveyor 5 and blows onto the wire ring group 2 placed thereon, the cooling rate is approximately uniform and there are almost no dead wind zones. I understand. As described above, the present invention can substantially uniformize the cooling rate of the dense wire part, intermediate part, coarse wire part, and chain part of the wire ring group, which is the intended purpose, so there is less variation in mechanical properties. This has an extremely beneficial effect on improving the quality of wire rods. In particular, it has not been found that it is possible to improve the cooling rate of the wire-dense part of the wire ring group, and therefore the technical value is high.

[Brief explanation of the drawing]

Fig. 1 is a plan view of an embodiment of the present invention, and Fig. 2 is a plan view of an embodiment of the present invention.
3 is an enlarged perspective view of the rail section and chain section shown in FIG. 2; FIG. 4 is an enlarged explanatory view of the nozzle for the dense line part shown in FIG. 2;
The figure is a sectional view taken in the conveying direction of the nozzle for the rough line part and the intermediate part shown in FIG. 2, and FIG. 6 shows the side guide. FIG. 7 is a plan view showing the wire rod polymerization state of the wire ring group, FIG.
Figure 3 is a diagram explaining the cooling test results of the comparative example.
Figures A, B, and C are explanatory diagrams showing the degree of occurrence of dead wind zones. 1... Laying head, 2... Cooling bed, 3...
Wire ring group, 4...Rail, 5...Chain,
6... Divided rail for chain, 7... Nozzle for coarse line part, 8... Nozzle for chain, 9... Nozzle for intermediate part, 10A, 10B... Nozzle for dense line part, 3A... Nozzle for dense line part. , 3B...middle part, 3C...
Rough wire portion, 10... Guide rail, 11... Guide chain, 12... Side guide, 13... Air blower.

Claims (1)

[Scope of Claim for Utility Model Registration] A wire rod after hot rolling is formed into a continuous spiral ring shape, and the wire rod formed into a ring shape is placed on a conveyor having a rail section and a chain section disposed on a cooling bed. In the apparatus for cooling the wire rod by fluid ejected from the cooling bed surface while transferring the ring with the center thereof shifted by a certain pitch, the chain rail section is divided in the length direction. death,
A chain part nozzle 8 is provided at the divided interval to spray cooling fluid upward from directly below the chain, and corresponds to the wire dense part 3A that occurs in the group of wire rings that are transported with the center shifted by a certain pitch. In the cooling bed apparatus, a group of line dense part nozzles 10A that sprays cooling fluid from the outer circumferential direction of the ring and a line dense part nozzle group 10B that sprays fluid from the inner circumferential direction of the ring are arranged alternately; Intermediate portion 3 generated in the wire ring group
At the cooling position corresponding to B, an intermediate nozzle 9 is provided in the same direction as the conveyance direction of the chain section and upward, and the wire roughness portion 3 generated in the group of wire rings to be conveyed is
A cooling device for hot-rolled wire rods, characterized in that a nozzle 7 for a rough wire portion is installed at a cooling bed position corresponding to C in a direction parallel to and upward in the same direction as the conveyance direction of the chain portion.