JPS609573B2 - Uniform cooling method for wire coils - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for uniformly cooling a wire coil.

Specifically, in order to cool substantially uniformly each part of the wire coil that is hot-rolled into a thick layered coil shape and transferred (passes through) within the surrounding environment, the high-temperature part of the coil is heat removed and the low-temperature part is heated. The coil surface layer part relates to a method for uniformly cooling a wire coil, which can reduce the temperature deviation of the coil by causing convection in the atmosphere of the surrounding environment. The hot-rolled steel wire rod is coiled from the winding head of the winding machine and placed on a transfer conveyor provided immediately after the coil. A method and apparatus for cooling wire rod coils using rolling heat while shifting the wire rod coils at regular intervals and overlapping each other on a conveyor belt are described, for example, in JP-A-51-64416, ``Method for cooling hot-rolled steel wire and its method. ``device''.

However, conventional cooling methods and devices cannot satisfactorily eliminate the temperature deviation between the outer surface of the coil and the polymerization center due to the difference in polymerization density of the wire coil, and it is difficult to measure the uniformity of cooling. That was difficult. Therefore, the present inventors improved the conventional method and device for cooling steel wire by using a conveyor having multiple steps to transport wire coils, and by reducing the number of wire rings that overlapped per unit length of the wire. We have developed a method and device for cooling the wire while transferring it in a coil with increased layer thickness, and have confirmed that it is extremely effective for uniform cooling.

(Japanese Unexamined Patent Publication No. 56-41324 "Cooling Method and Cooling Device for Hot Rolled Wire Village") Here, the thickness coil means that the wire rod fed on the transfer conveyor (conveyor with stepped portions) has a constant thickness. This means that there are 50 to 550 rings per wire coil transfer direction 1 in a state in which they overlap each other at shifted intervals.

Next, an outline of the cooling system disclosed in Tokukan Sho 56-41324 will be explained based on FIG. As shown in Figure 1,
The wire rod sent through the hot rolling mill and the cooling zone is wound into a coil by the winding head of the winding machine and dropped onto the next transfer conveyor (roller conveyor) 2.

The wire coils 3 stacked on the roller conveyor 2 are transferred in a superposed state in which each ring is shifted by a fixed interval as the conveyor moves, and is surrounded by a heat insulation cover 4 and placed in a heat retention zone divided into a plurality of parts. cooling stepwise along the desired cooling curve. Further, within this heat retention zone, the wire coil 3 is transferred in the form of a thick layered coil with a high polymerization density, and is loosened by one or more stepped portions 5 provided on the roller conveyor 2 and sprayed with a refrigerant. The thick coil that has left the heat retention zone is appropriately rapidly cooled and concentrated by the concentration device 6.In order to eliminate the temperature deviation between each part in the middle direction cross section of the thick coil, the coil is loosened at the above-mentioned coil loosening position. In addition to the refrigerant spraying, there is also a means to uniformize the temperature of the outer surface of the coil by observing the atmosphere in the heat retention zone, and a means to heat both sides and the lower surface of the coil with a heater, etc., if necessary. However, due to the polymerization form of the layered coil, when viewed from the cross section shown in Figure 2, the dense layered center C on both sides is the highest temperature, and the both sides S and the lower surface U on both green sides are the lowest. The present inventors have discovered this through experiments, and for this reason, coil loosening, refrigerant spraying, atmosphere lighting, and both side and lower surface temperature compensating means are used together.

All of these means are important for uniform cooling of the wire coil, but among them, the temperature compensation means for both sides and the bottom surface are different from the other means and are not used continuously, but are temporary measures. It is. However, this temperature compensation means is indispensable as a countermeasure for the low-temperature section of the wire coil, and is inextricably linked to the coil loosening and soot spraying as countermeasures for the high-temperature section, and must be effectively applied. The present invention has been made in view of the above points, and it is an object of the present invention to provide a method for uniformly cooling a wire coil, which can reduce the temperature deviation of a thick-layer coil.

Still another object of the present invention is to provide a temperature compensation method that allows easy temperature control in the middle and longitudinal directions of a transferred wire coil. Specifically, the present invention provides a method for uniformly cooling a wire rod that is hot-rolled, wound into a coil shape from a winding machine, and then transferred in a thick coiled state through an surrounding environment, to reduce the high temperature of the coil in the surrounding environment. For the lower part of the coil, heat is removed by blowing medium while loosening the coil on the steps of the conveyor, and for the lower temperature part of the coil, electric heaters installed on the sides and bottom of the wire coil are used to remove heat in the middle direction of the coil. By adjusting the arrangement density of the heaters, and by selectively adjusting the heating blocks that are divided into multiple parts in the longitudinal direction of the coil, it is possible to heat the entire surface layer of the coil by convection of the atmosphere in the surrounding environment to maintain a uniform temperature. The present invention provides a method for uniformly cooling a wire coil, which is characterized by reducing the temperature deviation of the coil.

The details of the present invention will be explained below based on the drawings.

Figure 3 shows the heat retaining cover 4 on the transfer conveyor 2.
FIG. 4 is a plan view showing the relationship between the transfer conveyor 2 and the heater 7 below it. As shown in the figure, electric radiant tubes 8 and ribbon heaters are installed in the heat insulating cover 4 at locations where temperature compensation is required for the layered coil 3, that is, at positions facing both side surfaces and both green side lower surfaces of the coil 3. Set up T. In addition, a non-contact side thermometer 9 is provided on the side of the heat insulating cover 4 and is oriented toward the side of the coil 3. The upper part of the heat insulating cover 4 monitors the atmosphere inside the cover and actively generates convection. A fan 10 is attached to generate the damage. Further, a silicon carbide plate 11 is disposed above the ribbon heater 7 to prevent the heater 7 from being grounded and to treat scale. Figure 5 is the third
The side view of the figure shows electric radiant tubes 8 serving as side heaters arranged in rows at regular intervals, and a lower heater 7 located between rollers constituting the conveyor.

A spray nozzle 12 is provided at a step position of the transfer conveyor 2 for spraying cold soot adjusted to a temperature below the coil temperature onto the loosened and falling wire ring. Furthermore, heat insulation cover 4
There is a heat extraction hole 1 in the ceiling to lower the temperature inside the cover.
3 and a cold air blowing hole 14 are formed. The thick layered coil 3 transferred inside the heat insulating cover 4 is sent onto the roller conveyor 2, and since each roller bearing of the roller conveyor 2 is located outside the heat insulating cover 4, the wire rod coil 3 is transferred through this roller. heat is easily released.

In particular, both edges of the lower surface of the thick-layered coil 3 in contact with the roller tend to radiate heat, and there is a risk of overcooling. For this reason, the above-mentioned lower surface heater 7 is installed below the coil to compensate for the temperature on the lower surface of the coil, but this temperature compensation is performed only when necessary, that is, when the lower surface of the coil deviates from the target cooling speed range (than the target cooling speed range). It only needs to be applied when the cooling rate is fast. For example, as shown in FIG. 4, such control of the lower surface heater 7 is performed by adjusting the arrangement density of the ribbon heaters 7 toward the center of the coil, with denser arrangement on both edges and coarser on the center side, so that the lower surfaces of both edges of the coil, where heat is particularly easily dissipated, are arranged densely on both edges of the coil. Configure so that it can be heated strongly. On the other hand, in the coil transfer direction (coil longitudinal direction), a plurality of ribbon heaters 7 are divided into a plurality of heating blocks (as A, B, and C in the figure) as a unit, and each is independently heated.
It is sufficient to control the coil so that it can be turned on and off and heat the coil only in the necessary blocks. Further, the side heater 8 is also divided into a plurality of heating units in the coil transfer direction to perform selective heating. In the actual operation, a coil side heating device (for example, the side thermometer 9 in FIG. 3) that can continuously heat the predicted low temperature part of the thick-layered coil 3 is connected to the lower surface through an appropriate control section. It is connected to the operation section of the heater 7 and the side heater 8, and when a temperature lower than the target temperature is detected, the coil position is determined and the corresponding heating block is energized to selectively and quickly heat the low-temperature area. It is preferable to adopt an automatic control method of heating.

Of course, in this case, it is also possible to precisely control the heating temperature and heating time. In the above explanation, as one means for vertically reducing the temperature deviation of a thick-layered wire coil, we have explained temperature compensation especially in the low-temperature part of the thick-layered coil. In order to achieve this, it is necessary to further combine the above-mentioned temperature compensating means with the cooling of the atmosphere within the cover by a rope fan to equalize the temperature of the surface layer of the coil, and with the blowing of cold soot at the coil loosening position.

Although a ribbon heater and an electric radiant tube are shown as the bottom heater and the side heater, the present invention is not limited to these, and other known heating means such as gas direct firing or gas radiant tube can also be used.

However, in terms of operation and rapid heating, electric heaters are preferable. Next, the operation of the present invention will be explained with reference to the drawings. The hot-rolled wire rod is discharged from the winding machine into a coiled shape, and is placed on a roller conveyor 2 in a thick-layered coil 3.
The material is loaded as a heat insulating cover 4 and slowly cooled while being transferred inside the heat insulating cover 4.

Inside the heat retaining cover 4, a rope fan 10 blows cold air, and if necessary, cool air is blown in from a cold air blowing hole 14 and heat is removed from a heat removal hole 13. Further, the thick-layered coil 3 is unraveled at the stepped portion of the roller conveyor 2, and coolant is sprayed from the /zzle 12 to remove heat from the high temperature portion of the coil. Figure 6 shows the relationship between the ambient temperature inside the cover and the coil target speed range. It descends each time it is divided, and the range is slightly lower than the coil target speed range b. When the temperature of both sides and the lower surface of the thick-layer coil 3 deviates from the target cooling speed range, the side heater 8 and lower surface heater 7 of the relevant portions are activated immediately to selectively perform local heating to lower the temperature of the low temperature portion. According to experiments conducted by the present inventors, when the method of the present invention is used to slowly cool a steel wire, the coil reaches the target cooling speed shown vaguely in FIG. Within this range, the wire rods were cooled and the quality (mechanical properties) of the obtained wire products had little variation.

On the other hand, when the steel wire is cooled in a ribbon without using this temperature compensation means (Special Kansei No. 51-64416), the lower and side surfaces of the coil are cooled, as shown in Figure 6. The target refrigeration range was exceeded, and products with widely varying quality were obtained. A test example of this method is disclosed in FIG. 2 of Japanese Patent Laid-Open No. 56-41324, which was proposed by the applicant of the present invention. As explained above, according to the method of the present invention, the parts of the wire coil where the temperature tends to drop are selectively and rapidly heated, which helps to reduce the temperature deviation of the wire coil and enables uniform cooling of the wire.

Moreover, in the present invention, since the heating position can be adjusted both in the middle direction and in the longitudinal direction of the wire coil, it is possible to intensively heat only the parts that require temperature compensation. In addition, the atmosphere within the surrounding environment is uniformized, and the thickness of the coil can be loosened by the steps of the conveyor and heat can be removed by spraying liner medium, so the cooling rate of each part of the coil is almost uniform. This has the effect of reducing the temperature deviation of the coil and uniformly cooling the bran coil.

[Brief explanation of the drawing]

FIG. 1 is an overall side view showing an outline of a cooling line for hot-rolled wire, FIG. 2 is a schematic cross-sectional view of a wire coil on a roller conveyor, and FIG. 3 is a temperature compensation means for carrying out the present invention. FIG. 4 is a plan view showing an example of the bottom heater, FIG. 5 is a side view of FIG. 3, and FIG. 6 is a chart showing changes in the ambient temperature inside the heat insulation cover. . 1... Laying head, 2... Transfer conveyor (roller conveyor), 3... Thick layer coil, 4... Heat retention cover, 7... Bottom heater, 8... Side heater , 9... Side green meter, 10... Takaazusa fan, 1
1...Silicon carbide plate, 12...Cooling spray nozzle. Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. When uniformly cooling the wire after being hot-rolled and wound into a coil by a winding machine and then being transferred in a thick-layered coil state through the surrounding environment, for the high temperature part of the coil in the surrounding environment, Heat is removed by blowing refrigerant while loosening the coil on the steps of the conveyor.For the low-temperature part of the coil, electric heaters are installed on the sides and bottom of the wire coil, and the arrangement density of the heaters can be adjusted in the width direction of the coil. In addition, the longitudinal direction of the coil is heated by local heating by selectively adjusting the heating block divided into multiple parts, and the entire surface layer of the coil is kept at a uniform temperature by convection of the atmosphere in the surrounding environment. A method for uniformly cooling a wire coil characterized by reducing deviation.