JPH0745089B2 - Twin roll type continuous casting machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a twin roll type continuous casting machine for continuously casting strips.

[Prior Art] Although a slab rolling method is generally used as a means for producing a strip from a molten metal, a twin roll type continuous casting machine capable of directly casting a strip from the molten metal has recently been devised. There is.

The twin roll type continuous casting machine, as shown in FIG. 6, includes a pair of cooling rolls a whose inner surfaces can be cooled with water or the like.
The strips b to be cast are arranged in parallel with each other while being kept in the gap G corresponding to the thickness of the strip b, and the molten metal c is introduced into the gap G so that both rolls
The strip plate b is continuously cast from the gap G while rotating.

[Problems to be Solved by the Invention] However, when the molten metal c is replenished by a slit nozzle at the bottom of the tundish, the flow rate is too large unless the slit width is made small enough to easily clog the cooling roll a.
It melts the solidified shell that is being formed on top.

Further, as shown in FIG. 7, since a large number of cylindrical nozzles e are provided in the lower width direction of the tundish d, the diameter of each cylindrical nozzle e becomes too small and the nozzles tend to be clogged. On the contrary, if the diameter of each cylindrical nozzle e is increased, the number of the cylindrical nozzles e must be reduced, and the flow of the molten metal in the pool becomes uneven.

[Means for Solving Problems] The present invention is intended to solve the above problems and improve the quality of a cast piece by allowing molten metal to be gently poured into a pool. In the twin roll type continuous casting machine of the present invention, a pair of cooling rolls 1 arranged in parallel to each other, a pair of side dams 7 arranged so as to abut one end and the other end of both cooling rolls 1, and molten metal inside A tundish 2 that can be stored and has a plurality of pouring holes 3 formed in a row at the bottom.
And a guide made of refractory material having substantially vertically extending pouring nozzle holes 5 and 5 ', each of which has an upper end communicating with the pouring hole 3 of the tundish 2 and a lower end formed into a flat slit shape. The tundish 2 is arranged above both cooling rolls 1 so that each pouring hole 3 is provided directly above the gap G formed between both cooling rolls 1 by providing the nozzles 4, 4 ′, 4 ″. Then, the guide nozzle is arranged so that the upper end of the pouring nozzle hole 5 communicates with the pouring hole 3 and the flat slit-shaped lower end of the pouring nozzle hole 5 faces the gap G formed between both cooling rolls 1. The upper end of 4 is fixed to the lower surface of the tundish 2.

[Operation] In the twin roll type continuous casting machine of the present invention, due to the shape of the lower end of the pouring nozzle holes 5, 5 ', the molten metal supplied to the tundish 2 is guided by the guide nozzles 4, 4', 4 ". From the pouring nozzle holes 5, 5'to the gap G formed between the cooling rolls 1, the thin plate shape is smoothly discharged.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show a first embodiment of the present invention, in which 1,1 are a pair of cooling rolls arranged in parallel with each other, 7,7 are a pair of side weirs, and the side weirs 7,7 are The cooling rolls 1 and 1 are arranged so as to come into contact with one end and the other end thereof.

Reference numeral 2 is a tundish capable of storing molten metal inside, and a plurality of pouring holes 3 for regulating the flow rate are formed in a row (in the width direction of the slab) at the bottom of the tundish 2.

The tundish 2 is arranged above the cooling rolls 1 and 1 so that the pouring holes 3 are located directly above the gap G formed between the cooling rolls 1 and 1.

4 is a refractory guide nozzle, and the guide nozzle 4
The guide nozzle is provided with a substantially vertically extending pouring nozzle hole 5 whose upper end can communicate with the pouring hole 3 of the tundish 2 and whose lower end is narrowed into a flat slit shape. Reference numeral 4 denotes a tan so that the upper end of the pouring nozzle hole 5 communicates with the pouring hole 3 and the flat slit-shaped lower end of the pouring nozzle hole 5 faces a gap G formed between both cooling rolls 1. It is fixed to the lower surface of the dish 2.

With the above configuration, when the molten metal in the ladle is supplied to the tundish 2, the molten metal in the tundish 2 passes through the respective pouring holes 3 for regulating the flow rate and then the pouring nozzle hole 5 of the guide nozzle 4 is introduced. Flow into.

At this time, the flow rate of the molten metal flowing from the tundish 2 into the pouring nozzle hole 5 of the guide nozzle 4 is adjusted by the pouring hole 3, and the pouring nozzle hole 5 of the guide nozzle 4 is adjusted.
Due to the shape of the lower ends of the pouring nozzle holes 5 and 5 ′, the molten metal flowing out from the outside flows smoothly toward the gap G formed between the cooling rolls 1 in the form of a thin plate. Therefore, an appropriate amount of molten metal is gently poured into the molten metal pool 6 formed between the guide nozzle 4 and the cooling rolls 1 and 1 without causing clogging.

Therefore, the molten metal supplied between the cooling rolls 1 and 1 melts the solidified shell that is being formed on the cooling roll 1 or disturbs the scene of the molten metal already supplied between the cooling rolls 1. And the product quality of the slab is improved.

FIG. 3 is an explanatory view of a guide nozzle 4'used in the second embodiment of the present invention. In the configuration substantially similar to that in the first embodiment, three sets of pouring holes 3 and pouring nozzle holes 5 are provided. FIGS. 4 and 5 are explanatory views of the guide nozzle 4 ″ used in the third embodiment of the present invention, and the guide nozzle 4 ″ has substantially the same structure as in the first embodiment. This is an example in which the pouring nose hole 5'in the inside has a two-step slit shape, and the width of the lower slit 8 is significantly smaller than the width of the upper slit 9.

In the case of the present embodiment, the upper slit 9 of the pouring nozzle hole 5'acts as a molten metal pool, the flow of the molten metal becomes uniform and gentle, and the molten metal can be poured gently without clogging the pool. Therefore, the product quality of the slab is improved as in the above-described embodiment.

The twin roll type continuous casting machine of the present invention is not limited to the above-mentioned embodiment, and it goes without saying that various modifications can be made without departing from the scope of the present invention.

[Advantages of the Invention] As described above, in the twin roll type continuous casting machine of the present invention, the bottom of the tundish 2 having the plurality of pouring holes 3 formed in a row at the bottom is poured onto the bottom of the tundish 2 and the top of the tundish 2 is poured. A refractory guide nozzle 4,4 ', 4 "having a substantially vertical pouring nozzle hole 5,5' formed in a shape that can be communicated with the melt hole 3 and has a lower end narrowed into a flat slit shape. Fix and fix the bottom end of the flat nozzle of the pouring nozzle hole 5 to both cooling rolls 1.
Since it faces the gap G formed between the cooling rolls 1, the molten metal can have a thin plate shape and smoothly flow out toward the gap G formed between the cooling rolls 1.

Therefore, the molten metal supplied between the cooling rolls 1 and 1 melts the solidified shell that is being formed on the cooling roll 1 or disturbs the scene of the molten metal already supplied between the cooling rolls 1. It has the excellent effect of improving the product quality of the cast slab.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view of a first embodiment of a twin roll type continuous casting machine of the present invention, FIG. 2 is a view taken in the direction of arrows II-II in FIG. 1, and FIG. FIG. 4 is a partial explanatory view of a second embodiment of the invention, FIG. 4 is a partial explanatory view of a third embodiment of the present invention, FIG. 5 is a view in the direction of VV of FIG. 4, and FIG. FIG. 7 is an explanatory view showing an example of a casting machine, and FIG. 7 is an explanatory view showing a pouring state of the continuous casting machine shown in FIG. 1 is a cooling roll, 2 is a tundish, 3 is a pouring hole, 4,
4'and 4 "are guide nozzles, 5,5 'are pouring nozzles, and 7 is a side weir.

Claims (1)

[Claims] 1. A pair of cooling rolls (1) arranged in parallel with each other, a pair of side dams (7) arranged so as to abut one end and the other end of both cooling rolls (1), and molten metal inside. The tundish (2) that can be stored and has a plurality of pouring holes (3) formed in a row at the bottom, and the upper end can communicate with the pouring hole (3) of the tundish (2) and the lower end can A refractory guide nozzle (4) (4 ') (4 ") having a substantially vertical pouring nozzle hole (5) (5') formed in a flat slit shape. Tundish (2) so that the pouring hole (3) is located directly above the gap (G) formed between both cooling rolls (1).
Is arranged above both cooling rolls (1), the upper end of the pouring nozzle hole (5) communicates with the pouring hole (3), and the flat slit-shaped lower end of the pouring nozzle hole (5) is both cooling rolls. A twin roll continuous casting machine characterized in that an upper end of a guide nozzle (4) is fixed to a lower surface of a tundish (2) so as to face a gap G formed between (1).