KR200181426Y1 - Holding cover for width direction temperature equality in hot strip mill - Google Patents

Abstract

The present invention is installed on top of a hot object such as a bar, slab or strip in a blast furnace or mini mill hot rolling mill to reflect the high temperature radiant energy emitted from the object, thereby causing a temperature drop. The present invention relates to a heat dissipation plate for widthwise uniformity in a hot rolling apparatus in which the shape of the heat sink is minimized.

The present invention is installed in parallel to the bar, slab or strip in the heat sink that reflects the energy radiated from the bar, slab or strip to reduce the temperature drop, the heat sink (30 to 33) is provided with a widthwise temperature equalization means It is characterized by that.

By the configuration and operation of the present invention as described above, to reduce the temperature drop of the widthwise end of the hot object, such as bar, slab or strip, and to improve the product quality by reducing the temperature deviation of the width direction, A useful effect is provided to prevent coil winding failures.

Description

Heat-dissipating plate for temperature uniformity in hot rolling equipment {HOLDING COVER FOR WIDTH DIRECTION TEMPERATURE EQUALITY IN HOT STRIP MILL}

The present invention relates to a heat sink, and more particularly, high-temperature radiation emitted from the object by being installed on a high-temperature object such as a bar, slab, or strip in a blast furnace or mini-mill hot rolling mill. The present invention relates to a heat dissipation plate for temperature uniformity in the width direction in a hot rolling facility in which the shape of the heat dissipation plate reflects energy to minimize a temperature drop.

1 is a schematic view showing a heat sink installed in the blast furnace mill hot rolling mill, Figure 2 is a graph showing the temperature distribution in the width direction of the slab or strip bar temperature measured at the exit of the blast furnace mill hot-rolled mill and the entrance of the finishing mill.

In addition, Figure 3 is a schematic diagram showing a heat sink installed in the mini mill hot rolling mill, Figure 4 is a graph showing the temperature distribution in the width direction of the bar, slab, or strip measured in the heat sink side of the mini mill hot rolling mill and the input of the finishing mill, generally the heat sink ( Holding Cover) is installed on the upper part of high temperature object to reflect the energy radiated from the object back to the object to minimize the temperature drop.The material of such heat sink is ENCO Panel, Inconel Series or SUS Plate etc. Has been used and has a certain effect on preventing the temperature drop of an object that is actually hot.

At this time, since the conventional heat sinks 11 and 23 are installed in parallel with the bars 14 and 25 as shown in FIGS. 1 and 3, there is a problem in that the efficiency of preventing the temperature drop is low.

That is, since the radiant energy of a hot object is emitted from the surface of the object, in the case of a large object, the amount of radiant energy emitted at the center of the width of the object and the end of the width is different, and at the end of the width is emitted from a hot object Since the radiated energy cannot be effectively reflected back to a high temperature object, the temperature at the end of the width is lower than the center of the width.

As shown in FIG. 1 and FIG. 2, it can be seen that the width direction temperature of the bar 14 is constant at the exit side of the heating furnace 10, but at the entrance side of the finishing mill 12 after passing through the heat sink 11. The temperature at the end of the width is lower than the difference, the difference is more than 20 ℃.

Meanwhile, as shown in FIG. 3, in the mini mill hot rolling mill, a heat sink 23 is installed between a reduction unit 22 and an inductive heater (not shown). The heat dissipation plate 23 is installed in parallel to the hot bar 25 extracted from the reduction unit 22 to prevent the temperature drop of the bar 25.

Unlike the hot rolling mill of the blast furnace mill, the mini mill hot rolling mill does not have a process of heating a bar or slab using a heating furnace, and the edge heater (Edge) located at the rear end of the player 20 is a bar or slab extracted from the player 20. Since the edge of the bar 25 is heated by using the heater 21, the temperature is lowest at the 1/4 and 3/4 of the bar width, and the heat sink 23 installed in parallel with the bar 25 is removed. When used, this widthwise non-uniform temperature distribution has a disadvantage that it continues to the entry of the finishing mill 24.

As shown in FIG. 3 and FIG. 4, the temperature deviation was 30 ° C. or more before the heat sink 23, and 20 ° C. or more at the inlet side of the finishing mill 24.

When the bar 25 having a non-uniform width direction is rolled and wound in a later step, there is a problem of causing product quality defects due to the width direction deviation, tearing of the plate during rolling, or winding failure of the coil. there was.

The present invention was devised to solve the problems of the prior art as described above, an object of the present invention is to reduce the temperature drop in the widthwise end of the high-temperature object, hot rolling equipment that can reduce the temperature deviation in the width direction Its purpose is to provide a heat dissipation plate for widthwise temperature uniformity in the invention.

1 is a schematic view showing a heat sink installed in the blast furnace mill hot rolling mill.

Figure 2 is a graph showing the temperature distribution in the width direction of the bar, slab or strip temperature measured at the blast furnace mill hot-rolling furnace exit side and the finishing mill inlet side.

Figure 3 is a schematic view showing a heat sink installed in the mini mill hot rolling mill.

Figure 4 is a graph showing the temperature distribution in the width direction of the bar, slab or strip temperature measured at the heat sink side and the finishing mill entrance side of the mini mill hot rolling mill.

5 to 8 is a front schematic view showing an embodiment of a heat sink for widthwise temperature uniformization in a hot rolling facility according to the present invention.

9 is a view showing an experimental example for explaining the effect of the present invention.

<Explanation of symbols for main parts of the drawings>

10: heating furnace 12, 24: finishing mill

20: player 30 to 33: heat sink

35: Bar

In order to achieve the above object, the heat sink is installed parallel to the bar, slab or strip to reflect the energy radiated from the bar, slab or strip to reduce the temperature drop, the heat sink is provided with a widthwise temperature equalization means A heat sink for widthwise temperature uniformization in a hot rolling facility is provided.

In the present invention, the widthwise temperature equalizing means is characterized in that both ends of the widthwise direction of the heat sink are bent downward at a 45 ° angle or bent downward at a curvature of 120 mm.

Further, in the present invention, the widthwise temperature homogenizing means may be bent upwardly in a '1/4' shape at a quarter angle and a third quarter in the width direction of the heat sink, or at a curvature of 2,020 mm at a 30 ° angle. It is characterized by being bent.

Hereinafter, the present invention will be described in more detail with reference to the drawings showing preferred embodiments.

5 to 8 show an embodiment of the heat dissipation plate in the width direction in the hot rolling facility according to the present invention, the heat dissipation plate according to this, as shown in Figure 5, bar 35 or The widthwise both ends of the heat dissipating plate 30 provided in parallel on the upper part of the slab or strip are bent downward at a predetermined angle (0 ° <θ ≦ 90 °, 45 ° in FIG. 5).

In addition, as shown in FIG. 6, both widthwise ends of the heat dissipation plate 31 are bent downward as a predetermined curvature (R = 100 to 2,000 mm, about 120 mm in FIG. 6), or as shown in FIG. 7. A quarter point and a third quarter point in the width direction of the heat sink 32 are bent upward in a '∧' shape having a predetermined angle (0 ° <θ ≦ 90 °, 30 ° in FIG. 6).

In addition, as illustrated in FIG. 8, the first quarter point and the third quarter point in the width direction of the heat sink 33 are bent upward as a gentle curvature (R = 500 to 4,000 mm, about 2,020 mm in FIG. 8). It compensates the temperature at the 1/4 and 3/4 points by using the reflection of the radiant energy emitted from the bar 35 when the temperature at the 1/4 and 3/4 points in the width direction of the bar 35 is low. This is to lower the temperature deviation in the width direction.

Hereinafter, the present invention will be described in more detail based on Examples.

(Example)

After the manufacture of the experimental apparatus to confirm the effect of the heat sink according to the present invention, the experiment was carried out and the temperature of the bar was measured.

As shown in Figs. 1 and 9, first, a thermocouple insertion hole was machined into the surface of the heating bar (length: 4,200 mm, width: 1,200 mm, thickness: 40 mm) 35. The holes were machined three at the center in the longitudinal direction of the bar 35 and at a position of 1/2, 1/4, and 10 mm from the end of the width in the width direction.

Thereafter, the heating bar 35 was heated to 1,200 ° C. in the heating furnace 10, and then isothermally maintained for 30 minutes or more. Next, after extracting the isothermally treated bar 35 and inserting a thermocouple (not shown) into a pre-fabricated thermocouple insertion hole, it is made horizontally with the lower heat sink as shown in Figures 5 and 6 and the width direction Both ends were bent at 45 ° and the bars 35 were insulated for about 1 minute with heat sinks 30 and 31 having a curvature of R = 120 mm, and then the temperature change at each site was measured. In this case, in order to prevent heat loss to the bottom of the bar 35, the heat sink was arranged up to 6,200 mm in the longitudinal direction, 2,000 mm in the width direction.

As a result, as shown in Table 1 below, when using the heat sinks 30 and 31 shown in Figures 5 and 6 of the present invention as compared to the conventional parallel heat sink, the amount of temperature drop at the widthwise end of the bar 35 is 1 It was confirmed that it can reduce by more than / 2.

Meanwhile, as shown in FIGS. 1, 3, 7, and 9, the bar 35 extracted at 1,200 ° C. in the heating furnace 10 is maintained at room temperature for 5 minutes, and then the edge of the bar 35 is again. The part was heated to 1,100 ° C using the edge heater 21. Subsequently, the thermocouple was inserted into the pre-processed hole of the bar 35, and the bar 35 was insulated with the heat sink 32 as shown in FIG. 7 for 1 minute, and then the temperature change of each part was measured. The results are shown in Table 2 below.

As shown in Table 2, when using the heat sink 32 according to the present invention, it was possible to reduce the temperature difference between the width center and the quarter of the width of the bar 35 compared to the conventional.

As described above, according to the present invention, it is possible to reduce the temperature drop at the widthwise end of a hot object such as a bar, slab or strip, to improve the product quality by reducing the temperature deviation in the widthwise direction, There is a useful effect that can prevent a poor winding.

Claims (5)

A heat sink installed parallel to a bar, slab or strip to reflect energy radiated from the bar, slab or strip to reduce temperature drop, The heat dissipation plate (30 to 33) is a heat dissipation plate for the width direction uniformity of the bar, characterized in that the width direction temperature equalization means is provided. The heat dissipation plate of claim 1, wherein the widthwise temperature equalization means is bent downward at a 45 ° angle in the width direction both ends of the heat dissipation plate (30). The heat sink for widthwise temperature uniformity of the bar according to claim 1, wherein the widthwise temperature equalizing means is bent downwardly at a width of both ends of the heat sink 31 as a curvature of 120 mm. According to claim 1, wherein the width direction temperature equalizing means is characterized in that the 1/4 in the width direction of the heat sink 32, and 3/4 is bent upward in the '∧' shape at a 30 ° angle Heatsink for widthwise temperature uniformity. The widthwise temperature homogenization of the bar according to claim 1, wherein the widthwise temperature equalization means is bent upwardly with a curvature of 2,020 mm and a quarter point in the width direction of the heat sink 33 and a third point in the width direction. Heatsink for.