JPH05277Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial field of application] The present invention is a twin-roll continuous casting machine for continuously casting strips, especially for preventing the adhesion and formation of solidified shells on the side seal plates. This invention relates to a twin-roll continuous casting machine that can uniformly pour molten metal over the entire width.

[Prior Art] Slab rolling is a common method for producing strips from molten metal, but in recent years a twin-roll continuous casting machine has been proposed that can directly cast strips from molten metal.

As shown in Fig. 5, this twin-roll continuous casting machine maintains a pair of cooling rolls a whose inner surfaces can be cooled with water or the like at a roll gap G corresponding to the thickness of the strip b to be cast. side seal plates c are provided at both ends of the cooling roll a, and a barrel seal plate d is provided in the axial direction of the cooling roll a to form a pool e of molten metal from the tundish. The molten metal in the pool e is guided to the roll gap G, and while both rolls a are rotated, a cooled and solidified strip b is continuously cast out from the gap.

[Problem to be solved by the invention] However, when replenishing the molten metal through the slit nozzle at the bottom of the tundish, the width of the slit provided over the entire width must be made small enough to easily clog, otherwise the flow rate would be too large and the slit nozzle formed on the cooling roll a. This melts the solidified shell that is being solidified.

Further, when a large number of cylindrical nozzles g are provided in the width direction of the lower part of the tundish f as shown in FIG. 6, the diameter of each cylindrical nozzle g becomes too small and is easily clogged. On the other hand, if the diameter of each cylindrical nozzle g is increased, the number of cylindrical nozzles g must be reduced, and the flow of the molten metal in the pool e will become uneven.

Furthermore, the solidified shell on the surface of the cooling roll a cooled by the cooling roll a grows abnormally at the triple junction where the molten metal contacts the side seal plate c, where the molten metal tends to stay and is easily cooled, and the cooling roll a and the molten metal. The grown solidified shell is eventually dragged by the solidified shell on the cooling roll a and falls off as if being torn off, and the fallen solidified shell gets caught in the roll gear cap, not only worsening the surface quality of the slab. There were problems such as partially thickening the plate, causing the plate to break, or damaging the side seal plate c when it fell off.

This invention solves the above conventional technical problems,
It is an object of this invention to enable uniform pouring of metal over the entire width while minimizing the adhesion of solidified shells at the triple point.

[Means for Solving the Problems] The present invention provides a twin roll continuous casting machine in which a pool is formed from cooling rolls arranged in parallel and side seal plates arranged on both end faces of the cooling rolls. A tundish that can accommodate molten metal is arranged above, and side pouring holes for regulating the side flow rate are formed at both ends of the bottom of the tundish in the width direction, and a wide side pouring hole for regulating the flow rate is provided in the middle part of the widthwise direction. A required number of holes are bored, and a refractory core is provided on the lower surface of the tundish, and the side channels provided on each side end surface of the core communicate with the side pouring holes, and the core The wide pouring slit provided in the middle of the lower end is installed so that it communicates with the wide pouring hole, and the ratio of the widthwise length of the wide pouring slit to the widthwise length of the pool is determined as the total flow rate. It is characterized in that the ratio of the flow rate of the wide-face pouring hole to

[Function] The molten metal flowing out from the side channel of the core through the side pouring hole of the tundish can prevent the growth of a solidified shell at the triple point near the side seal plate.

The molten metal from the wide pouring hole uniformly flows into the pool from the wide pouring slit in the core.

Since the length ratio in the width direction of the wide pouring slit is the same as the pouring ratio, the amount of molten metal poured into the pool is approximately uniform in the width direction, resulting in a uniform temperature distribution.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

1 to 3 show an embodiment of the present invention, in which reference numerals 1 and 1 denote cooling rolls that can be internally cooled and have variable roll gap G and rotational speed;
3 is a side seal plate, 3 is a tundish, and 4 is a sump. At both widthwise ends of the bottom of the tundish 3, there are side pouring holes 5, 5 for regulating the side flow rate.
are drilled with the required hole diameters, and wide pouring holes 6 with the required hole diameters are similarly drilled in the widthwise intermediate portion in the required number and at the required intervals.

A refractory core 7 having approximately the same length as the widthwise length of the tundish 4 is attached to the lower surface of the tundish 3. Side channels 8, 8 are provided at both ends of the core 7, respectively, and communicate with the respective side pouring holes 5, 5. A hot water chamber 10 is provided in the width direction of the middle part of the core 7, and the upper end of the hot water chamber 10 can be communicated with each of the wide surface pouring holes 6, and the lower part of the hot water chamber 10 is cut out at a wide angle. The outlet is a wide pouring slit 11.

In the above, the hole diameters of the side pouring holes 5, 5 and the wide pouring hole 6 are the width of the slab 12 to be cast,
The flow rate of the molten metal is determined by taking into account the thickness and production volume per unit time, and the flow rate of the molten metal that can prevent the formation of a solidified shell at the triple point is determined based on a rule of thumb.
Determine the pore size of 5. The ratio of the amount of wide-surface molten metal poured from the wide-surface pouring hole 6 to the total flow rate of molten metal from the tundish 3 and the ratio of the length W of the wide-surface molten metal pouring slit 11 to the total length L of the tundish 4 are approximately the same, and the wide-surface molten metal is poured. The total cross-sectional area of the slit 11 is set to be greater than the sum of the areas of the wide pouring holes 6.

With the above configuration, the tandate 3
The molten metal having a predetermined head height flows from each side pouring hole 5, 5 to each side channel 8, 8 of the core 7, and flows out from each outlet 9, 9 to the triple junction part of each side seal plate 2. This melts the solidified shell that tends to form at the triple point. Since the outlets 9, 9 are provided at wide angles, the flow of the molten metal spreads, and the solidified shell on the slab 12 side is not melted.

In addition, the molten metal flows from the wide pouring hole 6 of the tundish 3 to the oil chamber 10 of the core 7, and after being rectified, it flows uniformly in the width direction from the wide pouring slit 11 to the pool 4, and is silently thin without any turbulence. It flows out in the form of a plate. Thereby, the flow of the molten metal in the tundish 4 becomes uniform. Therefore, the partial increase in flow rate prevents the solidified shells on the cooling rolls 1, 1 from melting.

Furthermore, since the length W in the width direction of the wide pouring slit 11 is set to be the same ratio as the ratio of the flow rate of the wide pouring hole 6 to the total flow rate, the side Total flow rate: Wide surface flow rate = 2S:W, and the unit flow rate of the molten metal flowing into the pool 4 is uniform in the width direction, and the temperature distribution in the width direction is also uniform.

Therefore, the temperature of the molten metal flowing evenly and quietly in the width direction becomes uniform in the width direction of the pool 4, and the formation rate of the solidified shell on the cooling rolls 1, 1 also becomes uniform in the width direction, so that Continuously cast under certain conditions.

The flow rate of the molten metal required to melt the solidified shell that is formed at the triple point of the side seal plate 2 and cause product defects and to control its growth is determined in advance by the diameter of the side pouring hole 5 as described above. However, in actual production, if excess or deficiency occurs in the side flow rate due to variations in production conditions, etc., it can be adjusted by adjusting the head height of the molten metal in the tundish 3. The overall change in flow rate due to the change in head height can be countered by increasing or decreasing the rotational speed of the cooling rolls 1,1.

FIG. 4 shows another embodiment of the present invention, in which the outlet 9 of the side channel 8 provided at the side end of the core 7 is arranged to form an inverted T-shaped horizontal flow in a configuration substantially similar to that of the embodiment described above. This is an example of road 13.

In the case of this embodiment, the molten metal from the side flow path 8 flows out laterally through the horizontal flow path 13, the solidified shell at the triple point of the side seal plate 2 is melted more reliably, and the molten metal in the molten metal pool 4 is melted. The flow of molten metal is also made more uniform.

It should be noted that the twin-roll continuous casting machine of the present invention is not limited to the above-described embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

[Effects of the invention] As explained above, according to the twin roll continuous casting machine of the invention, the growth of solidified shells near the triple point of the side seal plate can be prevented by the side channels provided in the core. The wide pouring slit of the core allows the molten metal to be introduced quietly into the pool, and since the widthwise length of the wide pouring slit is set to the required length, the width of the molten metal flowing into the pool is controlled. The unit flow rate in the direction can be made substantially uniform, and the temperature distribution in the width direction of the molten metal in the pool can also be made substantially uniform. Therefore,
A solidified shell is always formed on the cooling roll under constant conditions, and groove plates with uniform quality in the width direction and length direction can be continuously manufactured.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of an embodiment of the casting machine of the present invention;
Fig. 2 is a view taken in the - direction of Fig. 1, Fig. 3 is a view taken in the - direction of Fig. 2, Fig. 4 is a partial explanatory view of another embodiment of the casting machine of the present invention, and Fig. 5. 6 is a diagram showing an example of a conventional twin roll type continuous casting machine, and FIG. 6 is a diagram showing another example of the conventional twin roll type continuous casting machine. 1 is a cooling roll, 2 is a side seal plate, 3 is a tundish, 4 is a pool, 5 is a side pouring hole,
6 is a wide pouring hole, 8 is a side channel, 11 is a wide pouring slit, 12 is a slab, and 13 is a horizontal channel.

Claims (1)

[Scope of utility model registration request] In a twin-roll continuous casting machine in which a pool is formed from parallel cooling rolls and side seal plates arranged on both end faces of the cooling rolls, a tundish that can accommodate molten metal is arranged above the twin rolls, and the tundish A side pouring hole for regulating the side flow rate is drilled at both widthwise ends of the bottom of the tundish, and a required number of wide pouring holes for controlling the flow rate are drilled in the middle of the same widthwise direction. A core made of a material is provided with a wide pouring slit that communicates with side channels provided on each side end surface of the core and the side pouring holes, respectively, and is provided in the middle of the lower end of the core. The wide pouring slit is installed so as to communicate with the wide pouring hole, and the ratio of the widthwise length of the wide pouring slit to the widthwise length of the pool is the same as the ratio of the flow rate of the wide pouring hole to the total flow rate. A twin roll continuous casting machine featuring: