JP2000000639A - Stirring continuous casting apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To remarkably restrain the vibration of a cylindrical water-cooled mold caused by stirring force to molten metal with a simple means in a stirring continuous casting apparatus. SOLUTION: This apparatus 1 is provided with the cylindrical water-cooled mold 13 which directs the axial line to the vertical direction and penetrates plural spouting holes 8 for cooling-water at the lower part of the peripheral wall, a cylindrical partition wall 5 surrounding this mold 13 to form a cooling- water pool 7 at the outer peripheral side of the cylindrical water-cooled mold 13 and a stirring machine 23 for fluidizing the molten metal in the peripheral direction by giving the stirring force to the molten metal (m) in the cylindrical water-cooled mold 13. A rubber elastic body 6 having 10%<=R<=40% to an impact resilence R, is interposed between the cylindrical water-cooled mold 13 and the cylindrical partition wall 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an agitated continuous casting apparatus,
In particular, a cylindrical water-cooled mold having a plurality of cooling water jet holes penetrated in the lower part of the peripheral wall with the axis line oriented in the vertical direction, and the mold formed to form a cooling water pool on the outer peripheral side of the cylindrical water-cooled mold. The present invention relates to an agitated continuous casting apparatus including a surrounding cylindrical partition wall and a stirrer for imparting a stirring force to flow the molten metal in the cylindrical water-cooled mold in a circumferential direction.

[0002]

2. Description of the Related Art Vibration occurs in the cylindrical water-cooled mold due to the stirring force. If this vibration is not sufficiently suppressed, the phenomenon in which the unsolidified portion inside the ingot breaks through the solidified portion on the outer periphery near the outlet in the cylindrical water-cooled mold, that is, breakout occurs and casting becomes impossible. May be invited. In order to avoid such a situation, generally, means such as strengthening the cylindrical water-cooled mold and its supporting structure is adopted.

[0003]

However, if the above-mentioned means is employed, the water-cooled mold and the supporting structure thereof become large and complicated, which leads to an increase in the size of the entire apparatus and an increase in production cost. A new problem has arisen.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an agitated continuous casting apparatus capable of greatly suppressing the vibration of a cylindrical water-cooled mold caused by the agitating force by simple means. .

[0005] To achieve the above object, according to the present invention,
A cylindrical water-cooling mold having a plurality of cooling water jet holes penetrated in the lower part of the peripheral wall with the axis thereof oriented vertically, and the mold is surrounded to form a cooling water reservoir on the outer peripheral side of the cylindrical water-cooling mold. In a stirring continuous casting apparatus provided with a cylindrical partition and a stirrer for imparting a stirring force for causing the molten metal in the cylindrical water-cooled mold to flow in the circumferential direction, the cylindrical water-cooled mold and the cylindrical partition There is provided a stirring continuous casting apparatus in which a rubber-like elastic body having a rebound resilience R of 10% ≦ R ≦ 40% is interposed.

Here, the rubber-like elastic body includes an elastic body made of rubber, an elastic body made of plastic, and the like. Further, the rebound resilience R is defined as R = (h ₁ / h) where, when a sphere with a constant load is freely dropped from a constant height h ₀ onto the rubber-like elastic body surface, the height of the sphere jumping up is h _{1. 0} ) × 100
(%).

The rubber-like elastic body whose rebound resilience R is defined as described above greatly suppresses vibration of the cylindrical water-cooled mold caused by the stirring force. As a result, the occurrence of breakout can be prevented and the casting operation can proceed smoothly.

Further, when a solidified substance adheres to the inner surface of the cylindrical water-cooled mold, when the molten metal that has flowed due to the stirring force collides with the solidified substance, the rubber-like elastic body is re-formed based on the rebound resilience. Partial radial outward deformation is allowed. As a result, the cooling water pool is compressed and the speed of the cooling water spouted from the spout holes is increased to increase the flow rate, so that the ingot is rapidly cooled, and the molten metal in the vicinity of the solidified material is also solidified or semi-solid. Since it is in a solidified state, the solidified matter is taken into the descending ingot and peeled off from the inner surface of the cylindrical water-cooled mold. When the solidified substance adheres to the inner surface of the mold, a concave mark is formed on the outer peripheral surface of the ingot, and a casting defect is caused.

In the rubber-like elastic body, when the rebound resilience R is R> 40%, the rubber-like elastic body exhibits substantially the same elasticity as the metal body, so that the vibration suppression effect is obtained and the occurrence of breakout is reduced. However, on the other hand, since the deformation permitting action cannot be obtained, the concave mark is easily generated. On the other hand, R <10
%, The state is substantially the same as when no rubber-like elastic body is interposed between the cylindrical water-cooled mold and the cylindrical partition, so that the occurrence of breakout increases and the deformation permitting action becomes excessive. As a result, the flow of the cooling water is blocked, so that the above-mentioned concave mark is easily generated.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An agitated continuous casting apparatus 1 shown in FIGS. 1 and 2 has a body 2 whose axis is directed vertically. Its trunk-like body 2, an inner peripheral wall 3 _1, the outer peripheral wall 3 ₂ disposed taking a predetermined interval in the outer peripheral side thereof, an annular upper end wall 4 ₁ existing in both walls 3 _1, 3 ₂ of the upper end side more configured an annular lower end wall 4 ₂ existing on both walls 3 _1, 3 ₂ of the lower end side.

[0011] the peripheral wall 3 ₁ upper cylinder 3a and the lower cylinder 3b
And In the upper cylindrical body 3a, the lower half thereof is formed to be thicker than the upper half 12 so that the annular step 11 is formed inside, and the cylindrical water-cooled mold 13 whose axis is directed vertically. Is configured. The cylindrical water-cooled mold 13 is made of an Al alloy (for example, A5052), and a plurality of cooling water ejection holes 8 penetrates the lower part of the peripheral wall. The ejection holes 8 are formed obliquely downward so that their axes converge at one point on the axis of the cylindrical water-cooled mold 13.

[0012] A cylindrical partition wall 5 so as to surround the inner peripheral wall 3 ₁ is disposed, thereon, on the lower opening is closed respectively by the lower end wall 4 _1, 4 _2. A rubber elastic body 6 having a rebound resilience R of 10% ≦ R ≦ 40% is interposed between the cylindrical water cooling mold 13 and the cylindrical partition wall 5. As shown in FIG. 3, the rubber-like elastic body 6 is an annular body fitted to the cylindrical water-cooled mold 13 below the inlet 8 a of each ejection hole 8, and has an inward annular shape at the lower end of the inner peripheral surface thereof. The portion 6b is sandwiched between the lower end surface of the cylindrical water-cooled mold 13 and the upper end surface of the lower cylindrical body 3b to seal therebetween. A cooling water reservoir 7 is formed on the outer peripheral side of the cylindrical water-cooled mold 13 by the cylindrical partition wall 5 and the rubber-like elastic body 6.

A spout 15 is fitted into the upper half portion 12 via a thin-walled cylindrical body 14 so as to be coaxial with the cylindrical water-cooled mold 13, and an annular lower part forming a downward molten metal outlet 16 is formed. The end face 17 contacts the annular step portion 11. Also the spout 15, annular retaining plate 18 is fitted in the portion that protrudes from the upper end wall 4 _1, the retaining plate 18 is fixed to the upper end wall 4 _1. The spout 15 is made of calcium silicate having adiabatic fire resistance. Alumina, silica, and the like are also used as spout constituent materials. Above the spout 15, a molten metal supply gutter 19 for performing horizontal pouring is arranged,
The downward hot water supply port 20 communicates with the upward molten metal receiving port 21 of the spout 15. In the molten metal supply gutter 19, a weir 19 b is provided on a bottom wall 19 a near the hot water supply port 20,
Impurities in the molten metal are blocked by the weir 19b.

[0014] cylindrical closed space 22 between the cylindrical partition wall 5 and the outer peripheral wall 3 _2, is an electromagnetic induction agitator 23 is disposed, the molten metal m of the agitator 23 is cylindrical water-cooled casting mold 13 and the spout 15. It Is applied in the circumferential direction. The stirrer 23 includes a laminated iron core 24 having a cylindrical shape, and a plurality of coils 25 wound around the laminated iron core 24. As shown in FIG. 4, the stratified iron core 24 includes a cylindrical portion 26 and a plurality of ridges 27 arranged on the inner peripheral surface thereof at equal circumferential intervals and extending in the generatrix direction. Each coil 25 is wound around the adjacent two ridges 27 so that one ridge 27 overlaps a part of the two coils 25. Stratified iron core 24
Is fitted to the cylindrical partition wall 5, and the distal end surface of each ridge 27 closely contacts the outer peripheral surface of the cylindrical partition wall 5. The laminated core 24 is fixed by a plurality of bolts 30 and nuts 31 to the member 29 placed on the lower end wall 4 ₂ of the annular support member 29.
A plurality of connectors 3 in two ratios for one coil 25
2 are prepared, and each connecting tool 32 is connected to the lower end wall 4 by watertight means.
It is attached to it through _two .

[0015] a plurality of water inlet 33 to the outer peripheral wall 3 ₂ are formed, the cooling water w is supplied into the closed space 22 through the water supply port 33. A plurality of through holes 34 are provided near the upper end of the cylindrical partition wall 5.
Are formed, and the cooling water w is supplied to the cooling water reservoir 7 through the through holes 34. The cooling water w cools the cylindrical water-cooled mold 13 and jets out from each jet hole 8 to cool the ingot I. The through hole 34 is also formed on the lower side of the cylindrical partition wall 5.

In order to supply lubricating oil between the water-cooled mold 13 and the molten metal m, there are the following lubricating oil passages around the spout 15. In the inner peripheral wall 3 _1, the lower plate 37 of the upper end wall 4 ₁ to the upper end of the upper cylinder 3a is integrally provided. Between the upper end wall 4 ₁ of the upper plate 38 and lower plate 37,
An annular path 39 surrounding the spout 15;
And a plurality of straight paths 40 extending in the radial direction. An inlet 41 formed in the upper plate 38 communicates with an end of each straight path 40, and the inlet 41 is connected to a refueling pump. As is clearly shown in FIG.
A cylindrical path 42 is formed between the inner peripheral surface and the outer peripheral surface of the cylindrical body 14, and a plurality of obliquely downwardly facing through holes 43 communicating between the cylindrical path 42 and the annular path 39 are formed between the upper half 12 and the lower plate 37. Are formed in the continuous portion. The lower end of the cylindrical path 42 communicates with a plurality of V-shaped outlets 44 radially arranged between the annular step 11 and the annular lower end face 17 of the spout 15.

In FIG. 1, for example, when a molten metal m having an Al alloy composition is supplied into a spout 15 from a hot water supply port 20 of a molten metal supply gutter 19, the molten metal m is electromagnetically generated by a stirrer 23 in the spout 15 and the cylindrical water-cooled mold 13. An agitating force is applied to flow in the circumferential direction, and then cooled by the cylindrical water-cooled mold 13 to obtain the ingot I.

During the casting operation, the rubber-like elastic body 6 having the rebound resilience R defined as described above greatly suppresses the vibration of the cylindrical water-cooled mold 13 caused by the electromagnetic stirring force. As a result, the occurrence of breakout can be prevented and the casting operation can proceed smoothly.

When the solidified material adheres to the inner surface of the cylindrical water-cooled mold 13 and the molten metal m flowing by the electromagnetic stirring force collides with the solidified material, the rubber-like elastic body 6 causes the cylindrical elastic body 6 to recycle based on its rebound resilience. Partial deformation of the water-cooled mold 13 outward in the radial direction is allowed. As a result, the cooling water pool 7 is compressed and the speed of the cooling water w jetted from the jet holes 8 is increased to increase the flow rate, so that the ingot I is rapidly cooled,
Since the melt m near the solidified material also solidifies or is in a semi-solidified state, the solidified material is taken into the descending ingot I and peels off from the inner surface of the cylindrical water-cooled mold 13. In a state where the solidified matter adheres to the inner surface of the mold 13, a concave mark is formed in a direction of a generatrix on the outer peripheral surface of the ingot, and a casting defect occurs.

Next, in order to determine the range of the rebound resilience R of the rubber-like elastic body 6, the rebound resilience R is 5%, 10%, and 2%, respectively.
Rubber-like elastic bodies 6 composed of seven types of acrylonitrile-butadiene rubber (NBR) of 0%, 30%, 40%, 50%, and 60% were produced. First, one kind of rubber-like elastic body 6
Was incorporated into the stirring continuous casting apparatus 1 in the same manner as described above, and a molten metal having an Al alloy composition shown in Table 1 was prepared.

[0021]

[Table 1]

And the diameter of the ingot I: 152 mm;
Casting speed: 170 mm / min; Lubricating oil: Mineral oil with PTFE particles added; Lubricating oil supply: 1 cc / min; Cooling water supply: 8
0 liter / min; molten metal temperature at the molten metal receiving port 21 of the spout 15: 650 ° C .; electromagnetic stirring coil: submerged 4-pole 12 coil type; stirring frequency: 50 Hz; The incidence of scars was determined. Using the remaining rubber-like elastic body, the same casting operation as described above was performed, and the occurrence rate of breakout and the like was determined in the same manner as above.

FIG. 5 shows the casting results. FIG. 5 shows that when the rebound resilience R of the rubber-like elastic body 6 is set to 10% ≦ R ≦ 40%, the occurrence of breakout and concave marks can be avoided.

As a constituent material of the rubber-like elastic body 6, besides the above-mentioned NBR, acrylic rubber (ACM, ANM) having a rebound resilience R of 30% ≦ R ≦ 40%, 20% ≦ R ≦ 40%
Fluoro rubber (FKM) is also used.

For comparison, an apparatus in which an annular body made of stainless steel (JISSUS304) is interposed between the cylindrical water-cooled mold 13 and the cylindrical partition wall 5 (Comparative Example 1), and both members 1
The same casting operation as described above was performed 50 times by using an apparatus (Comparative Example 2) in which an annular body, that is, a solid was not interposed between 3 and 5, and the number of breakouts and the diameter of cast 1
Table 2 shows the results of examining the number of concave marks per total number of ingots I (52 mm, length 2 m) (50-number of breakouts).

[0026]

[Table 2]

From Table 2 and FIG. 5, Comparative Example 1 corresponds to the case where the resilience R of the rubber-like elastic body 6 is R> 40%, and Comparative Example 2 shows that the resilience R of the rubber-like elastic body 6 is R It can be said that this corresponds to the case of <10%.

FIGS. 6 and 7 show another rubber-like elastic body 6. The rubber-like elastic body 6 is attached to the cylindrical water-cooled mold 13 below the inlet 8a of each ejection hole 8 as shown in FIG. An annular main body 6a to be fitted, a plurality of partitioning bodies 6c extending from the upper end surface of the annular main body 6a in the generatrix direction of the cylindrical water cooling mold 13 to partition the cooling water reservoir 7 into a plurality of sections, and an inner periphery of the annular main body 6a. An inward annular portion 3b provided at the lower end of the surface and sandwiched between the lower end of the cylindrical water-cooled mold 13 and the upper end of the lower cylindrical body 3b to seal therebetween. In this case, each partition 6
c has a length substantially equal to the length of the cooling water reservoir 7 in the up-down direction, and one or more inlets 8a of the orifices 8 are formed in the partitioning portion 7a of the cooling water reservoir 7 between the two adjacent partitioning bodies 6c. Communicate.

When the rubber-like elastic body 6 is configured as described above, the compression of the cooling water pool 7 accompanying the deformation permitting action is made to appear in the partitioning portion 7a between the two adjacent partitioning bodies 6c, and the ejection holes 8 are formed.
From the cooling water w can be further increased.

[0030]

According to the present invention, there is provided an agitated continuous casting apparatus capable of preventing the occurrence of a breakout and the occurrence of a concave mark in an ingot by employing the simple means as described above. be able to.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view of an example of an agitated continuous casting apparatus.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a sectional view of an example of a rubber-like elastic body.

FIG. 4 is a main part plan view showing a relationship between a laminated core and a coil.

FIG. 5 is a graph showing the relationship between the rebound resilience of a rubber-like elastic body and the incidence of breakouts and concave marks.

FIG. 6 is a plan view of another example of the rubber-like elastic body.

FIG. 7 is a sectional view taken along line 7-7 of FIG. 6;

8 is an enlarged view of a main part of another example of the continuous stirring casting apparatus, and FIG.
Corresponding to

[Explanation of symbols]

 Reference Signs List 5 cylindrical partition wall 6 rubber-like elastic body 6a annular main body 6c partition body 7 cooling water pool 8 ejection hole 8a inlet 13 cylindrical water-cooled mold 23 electromagnetic induction type stirrer m molten metal

[Procedure amendment]

[Submission date] April 20, 1999 (1999.4.2
0)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0025

[Correction method] Change

[Correction contents]

For comparison, an apparatus in which an annular body made of stainless steel (JISSUS304) is interposed between the cylindrical water-cooled mold 13 and the cylindrical partition wall 5 (Comparative Example 1), and both members 1
The same casting operation as described above was performed 50 times by using an apparatus (Comparative Example 2) in which an annular body, that is, a solid was not interposed between 3 and 5, and the number of breakouts and the diameter of cast 1
52 mm, was examined the number of total present number those Rino concave scars ingot I of length 2m, to give the results shown in Table 2. Ingo
Total number of cut I = 50-number of breakout occurrences

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction contents]

[0026]

[Table 2]

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeyoshi Nakamura 1-4-1, Chuo, Wako-shi, Saitama Prefecture Inside Honda R & D Co., Ltd. (72) Inventor Teruyuki Otani 1-4-1, Chuo, Wako-shi, Saitama Inside Honda R & D Co., Ltd. (72) Inventor Takashi Ide 1-10-1 Shinsayama, Sayama City, Saitama Prefecture Honda Engineering Co., Ltd. F-term (reference) 4E004 AA05 AA09 AC01

Claims (3)

[Claims] 1. A cylindrical water-cooled mold (13) having an axis oriented vertically and having a plurality of cooling water jets (8) penetrated in a lower part of a peripheral wall, and an outer peripheral side of the cylindrical water-cooled mold (13). In order to form a cooling water reservoir (7), a cylindrical partition wall (5) surrounding the mold (13) and the molten metal (m) in the cylindrical water-cooled mold (13) flow in the circumferential direction. In the continuous stirring apparatus provided with a stirrer (23) for imparting a stirring force to be applied, a rebound resilience R is 10% ≦ R ≦ between the cylindrical water-cooled mold (13) and the cylindrical partition (5). An agitated continuous casting apparatus characterized by interposing a rubber-like elastic body (6) of 40%. 2. The rubber-like elastic body (6) is an annular body fitted to the cylindrical water-cooled mold (13) below an inlet (8a) of each ejection hole (8). 2. The stirring continuous casting apparatus according to 1. 3. An annular main body (6a) fitted to the cylindrical water-cooled mold (13) below an inlet (8a) of each of the ejection holes (8), the rubber-like elastic body (6); The stirring device according to claim 1, further comprising a plurality of partition bodies (6c) extending from the annular main body (6a) in a generatrix direction of the cylindrical water-cooled mold (13) to partition the cooling water reservoir (7) into a plurality of sections. Continuous casting equipment.