JPH07110396B2 - Twin belt type continuous casting machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a twin-belt type continuous casting apparatus in which the temperature distribution in the width direction of a belt forming a mold is made uniform.

[0002]

2. Description of the Related Art FIG. 3 is a side view schematically showing an example of a conventional twin belt type continuous casting apparatus. As shown in the figure, 1
Each of the pair of endless belts 4 is wound around the top pulley 21 and the bottom pulley 2 supported by the bearing blocks 5 and 5'and the side pulley 3 supported by the bearing box 6 and the guide 7 to rotate and heat. In addition to being heated substantially evenly in the width direction by the container 9, a pair of belts 4
Of the cooling water nozzle 11 are backed up by the fin rolls 12 in the descending portion.
And cooled by the cooling pad 13. A mold for the moving wall is formed by the descending portion of the pair of belts 4 and the pair of side dams 8 which are sandwiched between both ends of the belt 4 and rotate endlessly in synchronization with the belt 4.

Molten steel L is continuously supplied to this mold, and the solidified strip-shaped slab S is guided downward by a guide roller apron 14 and pulled out by a pinch roll (not shown).

[0004]

In the conventional device shown in FIG. 3, the belt 4 is heated by the heater 9 before the top pulley 21, so that the heating portion comes into contact with the low temperature top pulley 21. When passing, the heat of the belt 4 is taken by the top pulley 21 to lower the temperature, and when it comes into contact with the molten steel L, it is partially heated and the temperature of the central portion of the widthwise belt 4 rises.
The temperature distribution in the width direction becomes uneven and the belt 4 is deformed. Since the portion of the belt 4 that undergoes thermal deformation is located at the initial solidification position of the slab S, the slab S has surface depressions and cracks.

Further, during casting of the slab S, the belt 4 is rotationally driven by the bottom pulley 2, and a tension is applied to the belt 4 by the side pulley 3 in order to suppress waviness of the belt 4 in the casting area. Therefore, this tension is concentrated on both ends of the belt 4, which has become low in temperature due to the uneven temperature distribution in the belt width direction. Due to this concentrated tension, the belt 4 is stretched at the edges, which promotes its deformation.

The present invention is intended to provide a twin-belt type continuous casting apparatus capable of eliminating the uneven temperature distribution in the width direction of the belt in the mold portion as described above.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a pair of belts endlessly wound around a top pulley, a bottom pulley and a side pulley to rotate is lowered and cooled between the top pulley and the bottom pulley. In the twin-belt type continuous casting apparatus in which a mold is formed by a part and a pair of side dams, the top pulley is provided with steam heating means.

[0008]

In the present invention, the top pulley of each of the pair of belts is heated by the steam heating means. The heated top pulley transfers and heats the rotating belt so that the temperature distribution in the width direction of the descending portion of the belt becomes substantially uniform. Then, while cooling the descending portion, a molten metal is supplied to a mold formed by side dams that seal the both ends thereof to be solidified, and is drawn out from below to continuously cast strip-shaped cast pieces.

As described above, by heating the belt by the top pulley so that the temperature distribution in the width direction of the belt forming the mold is substantially uniform, thermal deformation of the belt is prevented and the surface of the cast slab to be cast. Occurrence of dents and cracks is prevented. In addition, since the temperature distribution in the width direction of the belt is substantially uniform, the concentration of tension at both ends of the belt is prevented, the end extension of the belt is suppressed, and the life of the belt is extended.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. 1 is a side view showing an outline of a twin belt type continuous casting apparatus according to the embodiment, and FIG. 2 is a sectional view taken along line II-II of FIG.

1 and 2, 1 is a pair of top pulleys, which are supported by a bearing block 5. This top pulley 1 is formed in a hollow shape, and a steam supply port 1a is bored at one shaft end thereof, and is connected to a steam supply source (not shown) of a factory via a rotary joint 16 and a supply pipe 17. It is connected. Also, the top pulley 1
The inner pipe 15 is fitted into the other shaft end of the
The outer end of the exhaust pipe 1 is connected via a rotary joint 16 '.
Connected to eight. 2 is a pair of bottom pulleys,
It is arranged below the top pulley 1, is supported by a bearing block 5 ', and is connected to a drive device (not shown). Reference numeral 3 denotes a pair of side pulleys, which are arranged on both sides of the top pulley 1 and the potom pulley 2 and are provided with a guide 7
It is supported by a bearing box 6 fitted in.

Numeral 4 is a pair of belts, which are endlessly wound around the respective pulleys 1, 2 and 3, and cooling water nozzles 11 and bearings (not shown) are provided on the back surfaces of the parts of the pulleys 1, 2 and 3 facing downward. The fin rolls 12 supported by and the cooling pads 13 through which the cooling water circulates are arranged.

Reference numeral 8 denotes a pair of side weirs, which are endlessly connected with a large number of rectangular blocks, are adapted to rotate in synchronization with the belt 4, and the descending portion thereof is the pair of belts 4. It is sandwiched by both ends.

The descending portion of the belt 4 and the descending portion of the side dam 8 form a mold for the moving wall.

Reference numeral 9 is a heater, and both top pulleys 1
The belt 4 located in front of is disposed so as to pass through the inside thereof. Reference numeral 14 denotes a guide roll apron, which is arranged below both bottom pulleys 2.

In this embodiment constructed as described above, steam is supplied from the supply pipe 17 to the inside of the top pulley 1 through the rotary joint 16 to heat the steam, and the steam cooled and the condensed drain are fed into the inner pipe 15. , Through the rotary joint 16 ′ and the drain pipe 18.

Then, both side weirs 8 are rotated, a predetermined tension is applied to both belts 4 by the side pulleys 3, and a pair of belts 4 is made by the bottom pulley 2.
Is heated by the heater 9 while rotating the belt, and further the belt 4 is rotated by the top pulley 2 which is heated by the supply of steam.
To heat. The heating of the belt 4 by the top pulley 2 alleviates uneven temperature distribution in the width direction of the belt 4. The descending portion of the pair of belts 4 is cooled by the cooling water sprayed from the cooling water nozzle 11 and the cooling pad 13, and the molten steel L is applied to the mold by the moving wall formed by the pair of belts 4 and the pair of side dams 8. Is continuously supplied to continuously cast a strip-shaped slab S having a predetermined thickness t, is guided downward by a guide roller apron 14, and is drawn out by a pinch roll (not shown).

As described above, in this embodiment, the top pulley 1 heated by steam and heated up heats the belt 4 in the part where it descends to form casting, and the temperature distribution in the width direction of the belt 4 is almost the same. The belts 4 are even, which makes it possible to prevent thermal deformation of the belt 4 in the portion in contact with the molten steel L and prevent occurrence of dents or cracks on the surface of the slab S. Further, by making the temperature distribution in the width direction of the belt 4 substantially uniform, it is possible to prevent the tension from being concentrated at both ends of the belt 4, suppress the end extension of the belt 4, and prolong the life of the belt 4.

[0019]

As described above in detail, according to the present invention, the top pulley is provided with the steam heating means to heat the belt immediately before the casting zone, so that the uneven temperature distribution in the width direction of the belt is alleviated. Therefore, thermal deformation of the belt in the casting area is suppressed, and a high quality slab with good surface properties can be obtained.

Further, since the tension is not concentrated on both ends of the belt, the end extension of the belt can be suppressed and the life of the belt can be extended.

[Brief description of drawings]

FIG. 1 is a side view schematically showing a twin-belt type continuous casting apparatus as an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line II-II in FIG.

FIG. 3 is a side view schematically showing an example of a twin-belt type continuous casting apparatus of a conventional apparatus.

[Explanation of symbols]

 1 Top Pulley 2 Bottom Pulley 3 Side Pulley 4 Belt 8 Side Dam 11 Cooling Water Nozzle 13 Cooling Pad 15 Inner Pipe 16, 16 'Rotary Joint 17 Supply Pipe 18 Discharge Pipe L Molten Steel S Slab

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Noriyuki Kanai No. 1 Nishinosu, Oita-shi, Oita Pref. Nishinosu Nippon Steel Co., Ltd. (72) Toshiya Komori No. 1 Nishinosu, Oita-shi, Oita Pref. (72) Inventor Shoji Uehara 46-59, Nakahara, Tobata-ku, Kitakyushu, Fukuoka Prefecture, Nippon Steel Co., Ltd., Tobata Plant Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. A descendingly cooled portion between a pair of belts, which is endlessly wound around a top pulley, a bottom pulley, and a side pulley and rotates, and a pair of side dams. A twin-belt continuous casting machine for forming a mold, wherein the top pulley is provided with steam heating means.