JPH09308945A - Vertical type continuous casting method of aluminum alloy slab - Google Patents
Vertical type continuous casting method of aluminum alloy slabInfo
- Publication number
- JPH09308945A JPH09308945A JP12455496A JP12455496A JPH09308945A JP H09308945 A JPH09308945 A JP H09308945A JP 12455496 A JP12455496 A JP 12455496A JP 12455496 A JP12455496 A JP 12455496A JP H09308945 A JPH09308945 A JP H09308945A
- Authority
- JP
- Japan
- Prior art keywords
- cooling
- mold
- aluminum alloy
- ingot
- continuous casting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Links
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、厚さ 300mm以上×
幅1000mm以上の大矩形断面を有するアルミニウム合金ス
ラブの縦型連続鋳造方法に関するものである。TECHNICAL FIELD The present invention has a thickness of 300 mm or more.
The present invention relates to a vertical continuous casting method for an aluminum alloy slab having a large rectangular cross section with a width of 1000 mm or more.
【０００２】[0002]
【従来の技術】アルミニウム合金スラブの縦型連続鋳造
は既に広く知られており、アルミニウム合金溶湯を上下
開放式の強制冷却鋳型の上部から導入し、鋳型により一
次冷却して凝固殻を形成せしめるとともに、凝固殻を形
成した鋳塊を強制冷却鋳型の下部から引き出し、その引
き出されてくる鋳塊表面に冷媒流体を直接当て二次冷却
することにより行われる。そして、冷媒流体を直接当て
る二次冷却の形態としては、例えば特開昭52−126619号
公報、特公昭54−8611号公報、特開平 6−210402号公報
に記載されているように、鋳型下部に直接設けられた二
次冷却手段により、あるいはこの二次冷却手段に加えて
鋳型下方に設けた冷却手段とにより、あるいは鋳型下方
に設けた冷却手段のみにより行う等の形態がある。2. Description of the Related Art Vertical continuous casting of aluminum alloy slabs is already widely known. A molten aluminum alloy is introduced from the upper part of a forced cooling mold that opens and closes, and is primarily cooled by the mold to form a solidified shell. The ingot having the solidified shell formed therein is drawn out from the lower part of the forced cooling mold, and a refrigerant fluid is directly applied to the surface of the ingot to be secondarily cooled. Then, as a form of secondary cooling in which the refrigerant fluid is directly applied, for example, as described in JP-A-52-126619, JP-B-54-8611, and JP-A-6-210402, the lower part of the mold The secondary cooling means provided directly in the mold, the cooling means provided in the lower part of the mold in addition to the secondary cooling means, or only the cooling means provided in the lower part of the mold.
【０００３】ところで、上記アルミニウム合金スラブの
縦型連続鋳造方法においては、上記特許公報に見られる
ように、従来より鋳塊割れなどの問題のあることが知ら
れている。そしてこの問題を改善するために、特開昭52
−126619号公報では、鋳型の内壁部を冷却する水室を隔
壁にて多数の小室に分割し、コーナー部の小室に供給す
る冷却水量を少なく他の小室に供給する冷却水量を多く
することで、二次冷却により鋳型の内壁部に形成される
溶融金属の凝固殻をコーナー部と中央部とでほぼ同一高
さレベルになるように制御し鋳塊割れなどを防止する方
法が提案されている。また、特公昭54−8611号公報で
は、鋳型とは別に鋳型の下方に冷却手段を設け、鋳型に
よる冷却を比較的軽く、冷却手段による冷却を比較的強
く行うことで鋳塊割れなどを防止する方法が提案されて
いる。また、特開平 6−210402号公報では、鋳型とは別
に鋳型の下方に冷却手段を設け、鋳型では一次冷却のみ
を行い、冷却手段では液体冷却媒体を霧状に噴射して二
次冷却することで、二次冷却における液体冷却媒体量が
少ない場合にも確実に液体冷却媒体を制御して二次冷却
することで鋳塊割れなどを防止する方法が提案されてい
る。By the way, it has been known that there is a problem such as ingot cracking in the vertical continuous casting method for the aluminum alloy slab, as seen in the above patent publication. In order to improve this problem, Japanese Patent Laid-Open No.
In the -126619 publication, the water chamber for cooling the inner wall of the mold is divided into a large number of small chambers by partition walls, and the amount of cooling water supplied to the small chambers at the corners is small and the amount of cooling water supplied to the other small chambers is large. , A method of preventing ingot cracks by controlling the solidified shell of the molten metal formed on the inner wall of the mold by the secondary cooling so that the corner and the center have almost the same height level has been proposed. . Further, in Japanese Patent Publication No. 54-8611, a cooling means is provided below the mold separately from the mold, cooling by the mold is relatively light, and cooling by the cooling means is relatively strong to prevent ingot cracks and the like. A method has been proposed. In Japanese Patent Application Laid-Open No. Hei 6-210402, a cooling means is provided below the mold separately from the mold, only the primary cooling is performed in the mold, and the cooling means injects the liquid cooling medium in a mist state to perform the secondary cooling. Thus, a method has been proposed in which even when the amount of the liquid cooling medium in the secondary cooling is small, the liquid cooling medium is surely controlled to perform the secondary cooling, thereby preventing ingot cracks and the like.
【０００４】[0004]
【発明が解決しようとする課題】上述した提案方法の
内、特開昭52−126619号公報に提案の方法は、従来の小
断面（厚さ 100〜 150mm×幅 300mm程度）のスラブを鋳
造する場合に採用されてきたもので、この種の小断面ス
ラブを鋳造する鋳型においては、コーナー部の冷却水量
を減らし冷却能力を抑制することで鋳塊割れが効果的に
防止できた。そして、この方法は、その後に大矩形断面
スラブ（厚さ 300mm以上×幅1000mm以上）の鋳造がなさ
れるようになった際にも鋳塊割れが防止され得るとの考
えに基づいて採用されてきた。しかしながら、大矩形断
面スラブの鋳造では主に鋳塊表面から内部に進展する鋳
塊割れが発生することがあり、必ずしも十分な方法とは
言えない。Among the above-mentioned proposed methods, the method proposed in Japanese Unexamined Patent Publication No. 52-126619 casts a conventional slab having a small cross section (thickness of 100 to 150 mm × width of 300 mm). In a mold for casting this kind of small cross-section slab, ingot cracks could be effectively prevented by reducing the cooling water amount at the corners and suppressing the cooling capacity. This method has been adopted based on the idea that slab cracking can be prevented even when large rectangular cross-section slabs (thickness 300 mm or more x width 1000 mm or more) are subsequently cast. It was However, in the casting of a slab having a large rectangular cross section, ingot cracks that mainly progress from the ingot surface to the inside may occur, which is not always a sufficient method.
【０００５】一方、上述した提案方法の内、特公昭54−
8611号公報及び特開平 6−210402号公報に提案の方法
は、一次冷却と二次冷却といった縦方向の冷却能の最適
化を図るものであり、鋳塊割れなどの防止のためには、
縦方向の冷却能の最適化のみでは不十分であり、水平方
向の冷却能のバランスが重要となるが、現在までほとん
ど考慮されていないのが実情である。On the other hand, among the proposed methods described above, Japanese Patent Publication No.
The method proposed in JP-A-8611 and JP-A-6-210402 aims to optimize the vertical cooling capacity such as primary cooling and secondary cooling, and in order to prevent ingot cracking,
The optimization of the cooling capacity in the vertical direction is not sufficient, and the balance of the cooling capacity in the horizontal direction is important, but the fact is that it has hardly been considered until now.
【０００６】本発明は、上記の事情に鑑みなされたもの
であって、その目的は、鋳塊割れの無い大矩形断面スラ
ブ（厚さ 300mm以上×幅1000mm以上）の鋳造をなし得る
アルミニウム合金の縦型連続鋳造方法を提供するもので
ある。The present invention has been made in view of the above circumstances, and an object thereof is to provide an aluminum alloy capable of casting a large rectangular cross-section slab (thickness of 300 mm or more x width of 1000 mm or more) without ingot cracking. A vertical continuous casting method is provided.
【０００７】[0007]
【課題を解決するための手段】上記の目的を達成するた
めに、本発明に係るアルミニウム合金スラブの縦型連続
鋳造方法は、アルミニウム合金溶湯を上下開放式の強制
冷却鋳型の上部から導入し、鋳型により一次冷却して凝
固殻を形成せしめるとともに、凝固殻を形成した鋳塊を
強制冷却鋳型の下部から引き出し、その引き出されてく
る鋳塊表面に冷媒流体を直接当て二次冷却することによ
り厚さ 300mm以上×幅1000mm以上の大矩形断面のアルミ
ニウム合金スラブを鋳造するアルミニウム合金スラブの
縦型連続鋳造方法において、鋳型広面部の中央部分から
コーナー部に到る広面部の幅方向1／3 〜 1／4 の長さ
の両側方部分の冷却能を、広面部の中央部分の冷却能に
対し 0.8倍〜 1.5倍に設定して鋳型による一次冷却する
ものである。In order to achieve the above object, the vertical continuous casting method of an aluminum alloy slab according to the present invention, the molten aluminum alloy is introduced from the upper part of the upper and lower open type forced cooling mold, The primary cooling is performed by the mold to form a solidified shell, and the ingot with the solidified shell formed is pulled out from the lower part of the forced cooling mold, and the refrigerant fluid is directly applied to the surface of the ingot to be secondarily cooled. In the vertical continuous casting method for aluminum alloy slabs with a large rectangular cross section of 300 mm or more x 1000 mm or more in width, in the vertical continuous casting method of the aluminum alloy slab, the width direction from the center of the mold wide surface to the corner 1/3 in the width direction The cooling capacity of both sides of the 1/4 length is set to 0.8 times to 1.5 times the cooling capacity of the central part of the wide surface part for primary cooling by the mold.
【０００８】そして、上記アルミニウム合金スラブの縦
型連続鋳造方法においては、鋳型広面部の中央部分と両
側方部分の冷却能の制御を、鋳型を冷却する冷媒流体の
流量により行ってもよく、その場合の冷媒流体としては
冷却水であってもよい。In the vertical continuous casting method for the aluminum alloy slab, the cooling ability of the central portion and both side portions of the wide surface portion of the mold may be controlled by the flow rate of the refrigerant fluid for cooling the mold. In this case, the coolant fluid may be cooling water.
【０００９】また、上記アルミニウム合金スラブの縦型
連続鋳造方法においては、鋳型の下部から引き出されて
くる鋳塊表面の二次冷却を、鋳型下方に設けた冷却手段
により行ってもよい。Further, in the vertical continuous casting method for the aluminum alloy slab, the secondary cooling of the surface of the ingot drawn from the lower part of the mold may be performed by the cooling means provided below the mold.
【００１０】また更に、上記アルミニウム合金スラブの
縦型連続鋳造方法においては、鋳型の下部から引き出さ
れてくる鋳塊表面の二次冷却を、鋳型の下部に直接設け
られている二次冷却手段に加えて鋳型下方に 100〜 500
mm離して設けた冷却手段により行うとともに、二次冷却
手段における冷媒流体量を冷却手段における冷媒流体量
の 1／4 〜 3／4 に設定して行うようにしてもよい。Furthermore, in the vertical continuous casting method for the aluminum alloy slab, the secondary cooling of the surface of the ingot drawn from the lower part of the mold is performed by the secondary cooling means directly provided at the lower part of the mold. In addition 100 to 500 below the mold
The cooling means may be provided at a distance of mm, and the amount of the refrigerant fluid in the secondary cooling means may be set to 1/4 to 3/4 of the amount of the refrigerant fluid in the cooling means.
【００１１】以下、本発明の構成並びに作用について説
明する。本発明者等が、鋳造後の大矩形断面スラブ（厚
さ 300mm以上×幅1000mm以上）を観察してきた結果で
は、鋳塊が割れる場合は、鋳塊のコーナー部から幅中心
方向 1／4 の間の位置に割れが多く観察され、また同位
置の鋳型内初期凝固殻が薄くなっていることが分かっ
た。そこで、その原因を調査した結果、大矩形断面スラ
ブの場合、小断面スラブの場合と異なり、フロートから
流出する溶湯の流動が均一になりにくく前記位置に高温
溶湯が流れてくること、及びコーナー部が過剰に冷却さ
れにくいことが判明し、その上、上述したようにコーナ
ー部の冷却は、小断面スラブ鋳造と同様の考え方により
冷媒流体量（冷却水量）を減らし冷却能力を抑制してい
るため、鋳塊割れに大きく影響を及ぼす最表面の初期凝
固殻が薄くなり割れが発生することが判明した。The structure and operation of the present invention will be described below. The present inventors have observed a large rectangular cross-section slab (thickness of 300 mm or more x width of 1000 mm or more) after casting, and when the ingot is cracked, the width direction from the corner of the ingot to 1/4 of the width center direction It was found that many cracks were observed at the positions between them and the initial solidified shell in the mold at the same position was thin. Therefore, as a result of investigating the cause, in the case of the large rectangular cross-section slab, unlike the case of the small cross-section slab, the flow of the molten metal flowing out from the float is difficult to be uniform, and the high-temperature molten metal flows into the above-mentioned position, and the corner portion Was found to be difficult to cool excessively. Moreover, as described above, the cooling of the corners reduces the refrigerant fluid amount (cooling water amount) and suppresses the cooling capacity in the same way as the small cross-section slab casting. It was found that the initial solidified shell on the outermost surface, which greatly affects the ingot cracking, becomes thin and cracks occur.
【００１２】本発明は上記の調査結果を踏まえてなした
もので、鋳型広面部の中央部分からコーナー部に到る広
面部の幅方向 1／3 〜 1／4 の長さの両側方部分の冷却
能を、広面部の中央部分の冷却能に対し 0.8倍〜 1.5倍
に設定して鋳型内における一次冷却を均一に行い、コー
ナー部から幅中心方向 1／4 の間の鋳塊割れに大きく影
響を及ぼす最表面の初期凝固殻を均一に生成させること
で、鋳塊のコーナー部から幅中心方向 1／4 の間の位置
に発生する割れを防止するもので、このような作用効果
を得るには、鋳型広面部の中央部分からコーナー部に到
る広面部の幅方向 1／3 〜 1／4 の長さの両側方部分の
冷却能を、広面部の中央部分の冷却能に対し 0.8倍〜
1.5倍に設定する必要があり、 0.8倍未満では広面の両
側方部分の冷却能力が不足し割れ発生が起こる。また、
1.5倍を超えると広面の両側方部分の冷却能力が中央部
分より勝ち過ぎるため、中央部分の表面強度が低下し中
央部分の破断が問題となる。The present invention has been made in view of the above-mentioned investigation results, and it has been found that the width of the wide surface portion extending from the central portion of the wide surface portion of the mold to the corner portion is ⅓ to ¼ in the width direction. The cooling capacity is set to 0.8 to 1.5 times the cooling capacity of the central part of the wide surface area to uniformly perform the primary cooling in the mold, and it greatly reduces ingot cracking from the corner to the width center direction 1/4. By uniformly generating the initial solidified shell on the outermost surface, which prevents cracks from occurring at the position between the corner of the ingot and the width center direction 1/4, such an effect is obtained. In addition, the cooling capacity of both sides of the width direction 1/3 to 1/4 of the wide surface portion from the central portion of the mold wide surface portion to the corner portion is 0.8% less than that of the central portion of the wide surface portion. Double
It is necessary to set it to 1.5 times, and if it is less than 0.8 times, the cooling capacity of both sides of the wide surface will be insufficient and cracking will occur. Also,
If it exceeds 1.5 times, the cooling capacity of both side parts of the wide surface will be overwhelmed by that of the central part, so that the surface strength of the central part will be reduced and breakage of the central part will be a problem.
【００１３】一方、上記のように鋳型による一次冷却を
比較的均一に行うことで、大矩形断面スラブの初期凝固
殻による鋳塊割れが防止されるが、この効果をより確実
なものとするためには鋳型の下部から引き出されてくる
鋳塊表面の二次冷却を合わせ操作することが好ましい。
具体的には、鋳型の下部に直接設けられている二次冷却
手段に加えて鋳型下方に 100〜 500mm離して冷却手段を
設け、これら冷却手段により二次冷却を行うとともに、
二次冷却手段における冷媒流体量を冷却手段における冷
媒流体量の 1／4 〜 3／4 に設定して行うようにするも
ので、二次冷却手段は、通常、鋳型内冷却と連通してお
り鋳型内の冷却媒体流により左右されるため効果的な操
作が難しいが、冷却手段は独立して操作でき効果的な操
作が行え、合わせて操作することで、鋳塊割れ低減効果
を大きく向上させうる。On the other hand, by performing the primary cooling with the mold relatively uniformly as described above, ingot cracking due to the initial solidified shell of the large rectangular cross-section slab is prevented, but this effect is made more reliable. For this purpose, it is preferable to perform a secondary cooling operation on the surface of the ingot which is pulled out from the lower part of the mold.
Specifically, in addition to the secondary cooling means provided directly in the lower part of the mold, a cooling means is provided below the mold 100 to 500 mm apart, and the secondary cooling is performed by these cooling means,
The amount of the refrigerant fluid in the secondary cooling means is set to 1/4 to 3/4 of the amount of the refrigerant fluid in the cooling means, and the secondary cooling means is normally in communication with the in-mold cooling. Effective operation is difficult because it is influenced by the cooling medium flow in the mold, but the cooling means can be operated independently and can be operated effectively. sell.
【００１４】しかし、二次冷却手段の冷媒流体量が冷却
手段の冷媒流体量の 1／4 未満では、冷媒流量比が大き
過ぎ、鋳型下方の冷媒流のはね上がり、あるいは冷却不
足による鋳型直下でのアルミ溶湯の漏れ、更には水蒸気
爆発、ブレークアウトなどの危険が懸念される。また、
3／4 を超えると、鋳型下方に離して設けた冷却手段の
意味合いが薄れ、鋳塊割れ低減効果の期待が低下する。
また一方、冷却手段を鋳型下方 100mm以下の間隔で設け
る場合は、鋳型直下での冷媒流のはね上がりが発生して
危険であり鋳造自体が困難となる。また、冷却手段を鋳
型下方 500mmを超える間隔で設ける場合は、冷却手段に
よる冷却が遅れ鋳塊の割れやブレークアウトなどの危険
が懸念される。However, if the amount of the refrigerant fluid in the secondary cooling means is less than 1/4 of the amount of the refrigerant fluid in the cooling means, the refrigerant flow rate ratio is too large, the refrigerant flow splashes below the mold, or immediately below the mold due to insufficient cooling. There is concern about leakage of molten aluminum, steam explosion, and breakout. Also,
If it exceeds 3/4, the meaning of the cooling means provided below the mold is weakened, and the expectation of the effect of reducing ingot cracks is reduced.
On the other hand, when the cooling means is provided below the mold at an interval of 100 mm or less, the refrigerant flow splashes directly under the mold, which is dangerous and makes casting itself difficult. Further, when the cooling means is provided below the mold at an interval of more than 500 mm, cooling by the cooling means is delayed, and there is a risk of cracking or breakout of the ingot.
【００１５】なお、本発明で使用される冷媒流体として
は、普通には冷却水であるが、炭酸水や霧などの気体と
液体の混合（例えばミスト）、あるいは空気、窒素等の
気体であってもよい。The refrigerant fluid used in the present invention is usually cooling water, but it is a mixture of gas and liquid (for example, mist) such as carbonated water and mist, or gas such as air and nitrogen. May be.
【００１６】[0016]
【発明の実施の形態】以下、本発明の実施の形態を図面
を参照して説明する。図１は、本発明に係るアルミニウ
ム合金スラブの縦型連続鋳造方法に適用される鋳造装置
の説明図であって、ａは上面図、ｂは正断面図であっ
て、１は鋳型、２は冷却手段である。Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view of a casting apparatus applied to a vertical continuous casting method for an aluminum alloy slab according to the present invention, in which a is a top view, b is a front sectional view, 1 is a mold, 2 is It is a cooling means.
【００１７】鋳型１は、広面部３と短面部４とにより矩
形に形成され、その内部は、上部に貫通孔５を有する仕
切壁６によりヘッダ部７と鋳型部８に仕切られている。
またヘッダ部７には冷却水９を給水するための給水管10
が接続され、また更に鋳型部８の下部には冷却水９の噴
出口11が設けられている。仕切壁６に設ける貫通孔５
は、その大きさ及び／又はその数を調整することで、広
面部３の両側方部分の冷却能が中央部分の冷却能に対し
て 0.8倍〜 1.5倍に予め設定される。The mold 1 is formed in a rectangular shape by a wide surface portion 3 and a short surface portion 4, and the inside thereof is partitioned into a header portion 7 and a mold portion 8 by a partition wall 6 having a through hole 5 in an upper portion.
A water supply pipe 10 for supplying cooling water 9 is provided in the header section 7.
And a jet port 11 for the cooling water 9 is provided in the lower part of the mold part 8. Through hole 5 provided in the partition wall 6
By adjusting the size and / or the number thereof, the cooling capacity of both side parts of the wide surface part 3 is preset to 0.8 times to 1.5 times the cooling capacity of the central part.
【００１８】冷却手段２は、鋳造される矩形スラブＳの
長辺及び短辺の外側に間隔を開けて設置された角管12よ
り構成され、内壁13には噴出口14が、外側壁15には給水
管16が設けられている。この冷却手段２の冷却水17と上
記鋳型１の冷却水９の給水量の調節は図示省略した給水
管10及び給水管16に取付けられたバルブ等周知の手段に
より適宜行われる。なお、図中、符号18は注湯ノズル、
19はフロート、20は底台、21はスクリーンをそれぞれ示
す。The cooling means 2 is composed of square tubes 12 which are installed outside the long sides and the short sides of the rectangular slab S to be cast, with a space therebetween. The inner wall 13 is provided with a jet port 14 and the outer wall 15 is provided. Is provided with a water supply pipe 16. The water supply amount of the cooling water 17 of the cooling means 2 and the cooling water 9 of the mold 1 is appropriately adjusted by well-known means such as a water supply pipe 10 (not shown) and a valve attached to the water supply pipe 16. In the figure, reference numeral 18 is a pouring nozzle,
19 is a float, 20 is a base, and 21 is a screen.
【００１９】上記鋳造装置による鋳造は、予め冷却水９
及び冷却水17の流量調整を行う以外は従来と同様の要領
で行われ、鋳型１及び冷却手段２に冷却水９を通水しな
がらアルミ合金溶湯Ｍを注湯ノズル18、フロート19を介
して鋳型１の下部にセットされた底台20上に注湯すると
ともに、底台20を所定の鋳造速度で降下させて行われ
る。鋳型１内に注湯されたアルミ合金溶湯Ｍは、広面部
３の両側方部分の冷却能が中央部分の冷却能に対して
0.8倍〜 1.5倍になるように予め調整された鋳型部８の
内壁によって一次冷却されるため初期凝固殻が均一に生
成し、得られた鋳塊Ｓの鋳塊割れが低減される。以下、
その効果を実施例により説明する。For the casting by the above casting apparatus, the cooling water 9 is preliminarily used.
And the flow rate of the cooling water 17 is adjusted in the same manner as in the conventional method. While the cooling water 9 is being passed through the mold 1 and the cooling means 2, the molten aluminum alloy M is poured through the pouring nozzle 18 and the float 19. It is performed by pouring the molten metal on the bottom table 20 set at the bottom of the mold 1 and lowering the bottom table 20 at a predetermined casting speed. In the molten aluminum alloy M poured into the mold 1, the cooling ability of both side portions of the wide surface portion 3 is larger than that of the central portion.
Since it is primarily cooled by the inner wall of the mold part 8 adjusted in advance to 0.8 times to 1.5 times, the initial solidified shell is uniformly generated, and the ingot crack of the obtained ingot S is reduced. Less than,
The effect will be described by way of examples.
【００２０】[0020]
【実施例】上述した図１に示す装置部分を備える縦型連
続鋳造装置を用い、下記鋳造条件のもとで下記に実施例
及び比較例として示す冷却条件によりアルミニウム合金
の鋳造を行った。 EXAMPLE An aluminum alloy was cast under the following casting conditions under the cooling conditions shown in Examples and Comparative Examples below, using the above-described vertical continuous casting apparatus having the apparatus portion shown in FIG.
【００２１】〔実施例１〕鋳型１に供給される冷却水量
を 1.0m3／min とし、鋳型１の広面部３と短面部４のコ
ーナー部付近（コーナーから約30mm程度）を除き鋳型幅
全域にわたり、単位幅当たりの冷却水量を2.5l／min ・
cmで冷却して鋳造した。なお冷却手段２は使用しなかっ
た。鋳造されたアルミ鋳塊Ｓを調査した結果、鋳塊割れ
の発生頻度は 0.3％以下と低いものであった。[Example 1] The amount of cooling water supplied to the mold 1 was 1.0 m 3 / min, and the entire width of the mold except the corners (about 30 mm from the corners) of the wide surface part 3 and the short surface part 4 of the mold 1. The cooling water amount per unit width is 2.5 l / min.
It was cooled in cm and cast. The cooling means 2 was not used. As a result of investigating the cast aluminum ingot S, the occurrence frequency of ingot cracks was as low as 0.3% or less.
【００２２】〔比較例１〕鋳型１に供給される冷却水量
を実施例１と同じ 1.0m3／min とし、鋳型１の広面幅を
４等分し、その中央部の 1／2 幅部分を単位幅当たり冷
却水量3.04 l／min ・cmで、両側の 1／4 幅部分を単位
幅当たり冷却水量2.17 l／min ・cmで冷却して鋳造し
た。なお冷却手段２は使用しなかった。また短面部４の
単位幅当たりの冷却水量は2.17 l／min ・cmとした。こ
の比較例では、両側の 1／4 幅部分の冷却水量を中央部
の 1／2 幅部分の冷却水量の0.71倍（冷却水量比）とし
たため、鋳造されたアルミ鋳塊Ｓを調査した結果、鋳塊
割れの発生頻度は約 3.0％となり高いものとなった。[Comparative Example 1] The amount of cooling water supplied to the mold 1 was set to 1.0 m 3 / min, which was the same as in Example 1, the wide surface width of the mold 1 was divided into four equal parts, and the half width part of the central part was divided. The amount of cooling water per unit width was 3.04 l / min · cm, and the 1/4 width portions on both sides were cooled with the amount of cooling water per unit width of 2.17 l / min · cm and cast. The cooling means 2 was not used. The amount of cooling water per unit width of the short surface portion 4 was 2.17 l / min · cm. In this comparative example, the amount of cooling water in the ¼ width portions on both sides was 0.71 times the cooling water amount in the ½ width portion in the central portion (cooling water amount ratio), and as a result of investigating the cast aluminum ingot S, The frequency of ingot cracking was high at about 3.0%.
【００２３】〔実施例２〕比較例１における、両側の 1
／4 幅部分の冷却水量と中央部の 1／2 幅部分の冷却水
量を調節して冷却水量比を0.80倍にして鋳造した。鋳造
されたアルミ鋳塊Ｓを調査した結果、鋳塊割れの発生頻
度は 0.5％以下と低いものであった。[Example 2] 1 on both sides in Comparative Example 1
Casting was performed with the cooling water amount ratio adjusted to 0.80 times by adjusting the cooling water amount in the / 4 width portion and the cooling water amount in the center half width portion. As a result of investigating the cast aluminum ingot S, the occurrence frequency of ingot cracks was as low as 0.5% or less.
【００２４】〔実施例３〕比較例１における、両側の 1
／4 幅部分の冷却水量と中央部の 1／2 幅部分の冷却水
量を調節して冷却水量比を1.50倍にして鋳造した。本実
施例では、両側の1／4 幅部分の冷却水量が中央部の 1
／2 幅部分の冷却水量より多くなることから過冷却にな
ることが懸念されたが、問題なく鋳造がなされ、鋳造さ
れたアルミ鋳塊Ｓの鋳塊割れの発生頻度も 0.5％以下と
低いものであった。[Example 3] 1 on both sides in Comparative Example 1
Casting was performed with the cooling water amount ratio adjusted to 1.50 times by adjusting the cooling water amount in the / 4 width portion and the cooling water amount in the center half width portion. In this embodiment, the cooling water amount in the 1/4 width part on both sides is 1% in the central part.
/ 2 There was a concern that it would be overcooled because the amount of cooling water in the width part is larger than that in the width part, but there was no problem casting, and the frequency of occurrence of ingot cracks in the cast aluminum ingot S was as low as 0.5% or less. Met.
【００２５】〔実施例４〕冷却水を炭酸水に変更した他
は実施例１又は比較例１と同条件で鋳造した。その結
果、実施例１と同条件の場合には鋳造されたアルミ鋳塊
Ｓの鋳塊割れの発生頻度が 0.2％以下と低かったが、比
較例１と同条件の場合には鋳造されたアルミ鋳塊Ｓの鋳
塊割れの発生頻度が約 2.5％とになり、冷却水の場合と
同様の傾向が見られ、広面幅方向で冷却水量に大きな偏
りがあると、大矩形断面アルミニウム合金スラブの鋳造
では、鋳塊割れの発生頻度が多くなることが判明した。Example 4 Casting was carried out under the same conditions as in Example 1 or Comparative Example 1 except that the cooling water was changed to carbonated water. As a result, under the same conditions as in Example 1, the occurrence frequency of ingot cracks in the cast aluminum ingot S was as low as 0.2% or less, but under the same conditions as in Comparative Example 1, the cast aluminum The frequency of occurrence of ingot cracking of the ingot S is about 2.5%, the same tendency as in the case of cooling water is seen, and if there is a large deviation in the amount of cooling water in the wide surface width direction, the aluminum alloy slab with a large rectangular cross section It was found that in casting, the frequency of occurrence of ingot cracks increased.
【００２６】〔実施例５〕本実施例では、鋳型１に供給
される冷却水量を 0.6m3／min とし、鋳型１の広面部３
と短面部４のコーナー部付近（コーナーから約30mm程
度）を除き鋳型幅全域にわたり、単位幅当たりの冷却水
量を1.5l／min ・cmで冷却するとともに、冷却手段２に
供給される冷却水量を 1.7m3／min とし、鋳型幅全域に
わたり、単位幅当たりの冷却水量を 4.25l／min ・cmで
冷却して鋳造した。鋳造されたアルミ鋳塊Ｓを調査した
結果、鋳塊割れの発生頻度は 0.2％以下と低いものであ
った。[Embodiment 5] In this embodiment, the amount of cooling water supplied to the mold 1 is 0.6 m 3 / min, and the wide surface portion 3 of the mold 1 is used.
The cooling water amount per unit width is cooled to 1.5 l / min · cm over the entire width of the mold except for the vicinity of the corner portion of the short surface portion 4 (about 30 mm from the corner), and the cooling water amount supplied to the cooling means 2 is The amount of cooling water was 1.7 m 3 / min, and the amount of cooling water per unit width was 4.25 l / min · cm over the entire width of the mold, and casting was performed. As a result of investigating the cast aluminum ingot S, the occurrence frequency of ingot cracks was as low as 0.2% or less.
【００２７】〔比較例２〕鋳型１に供給される冷却水量
を実施例５と同じ 0.6m3／min とし、鋳型１の広面幅を
４等分し、その中央部の 1／2 幅部分を単位幅当たり冷
却水量1.83 l／min ・cmで、両側の 1／4 幅部分を単位
幅当たり冷却水量1.30 l／min ・cmで冷却し、その他の
条件は上記実施例５と同じにして鋳造した。なお短面部
４の単位幅当たりの冷却水量は1.30 l／min ・cmとし
た。この比較例では、両側の 1／4 幅部分の冷却水量を
中央部の 1／2 幅部分の冷却水量の0.71倍（冷却水量
比）としたため、鋳造されたアルミ鋳塊Ｓを調査した結
果、鋳塊割れの発生頻度は約 2.0％となり高いものとな
った。[Comparative Example 2] The amount of cooling water supplied to the mold 1 was set to 0.6 m 3 / min, which was the same as in Example 5, the wide surface width of the mold 1 was divided into four equal parts, and the half width part of the central part was divided. The amount of cooling water per unit width was 1.83 l / min.cm, and the 1/4 width portions on both sides were cooled with the amount of cooling water per unit width of 1.30 l / min.cm, and other conditions were the same as in Example 5 above. . The amount of cooling water per unit width of the short surface portion 4 was 1.30 l / min · cm. In this comparative example, the amount of cooling water in the ¼ width portions on both sides was 0.71 times the cooling water amount in the ½ width portion in the central portion (cooling water amount ratio), and as a result of investigating the cast aluminum ingot S, The frequency of ingot cracking was high at about 2.0%.
【００２８】〔実施例６〕比較例２における、両側の 1
／4 幅部分の冷却水量と中央部の 1／2 幅部分の冷却水
量を調節して冷却水量比を0.80倍にして鋳造した。鋳造
されたアルミ鋳塊Ｓを調査した結果、鋳塊割れの発生頻
度は 0.4％以下と低いものであった。[Example 6] 1 on both sides in Comparative Example 2
Casting was performed with the cooling water amount ratio adjusted to 0.80 times by adjusting the cooling water amount in the / 4 width portion and the cooling water amount in the center half width portion. As a result of investigating the cast aluminum ingot S, the occurrence frequency of ingot cracks was as low as 0.4% or less.
【００２９】〔実施例７〕比較例１における、両側の 1
／4 幅部分の冷却水量と中央部の 1／2 幅部分の冷却水
量を調節して冷却水量比を1.50倍にして鋳造した。本実
施例では、両側の1／4 幅部分の冷却水量が中央部の 1
／2 幅部分の冷却水量より多くなることから過冷却にな
ることが懸念されたが、問題なく鋳造がなされ、鋳造さ
れたアルミ鋳塊Ｓの鋳塊割れの発生頻度も 0.4％以下と
低いものであった。[Example 7] 1 on both sides in Comparative Example 1
Casting was performed with the cooling water amount ratio adjusted to 1.50 times by adjusting the cooling water amount in the / 4 width portion and the cooling water amount in the center half width portion. In this embodiment, the cooling water amount in the 1/4 width part on both sides is 1% in the central part.
/ 2 There was a concern that it would be overcooled because the amount of cooling water in the width part was greater than that, but casting was performed without problems, and the frequency of occurrence of ingot cracks in the cast aluminum ingot S was as low as 0.4% or less. Met.
【００３０】[0030]
【発明の効果】以上説明したように、本発明に係るアル
ミニウム合金スラブの縦型連続鋳造方法によれば、従来
技術の欠点であった鋳塊割れの発生を防止することがで
き品質の良い大矩形断面スラブが得られる。また、これ
により鋳造以降の工程における鋳塊割れを原因とするト
ラブルが少なくなり、全体として生産性の向上及びコス
トの低減が期待される。As described above, according to the vertical continuous casting method for an aluminum alloy slab according to the present invention, it is possible to prevent the occurrence of ingot cracking, which is a drawback of the prior art, and to obtain a large quality. A rectangular cross section slab is obtained. This also reduces troubles caused by ingot cracks in the steps after casting, and is expected to improve productivity and reduce costs as a whole.
【図１】本発明に係るアルミニウム合金スラブの縦型連
続鋳造方法に適用される鋳造装置の説明図であって、ａ
は上面図、ｂは正断面図である。FIG. 1 is an explanatory view of a casting apparatus applied to a vertical continuous casting method for an aluminum alloy slab according to the present invention, in which a
Is a top view and b is a front sectional view.
１：鋳型 ２：冷却手段
３：広面部 ４：短面部 ５：貫通孔
６：仕切壁 ７：ヘッダ部 ８：鋳型部
９, 17：冷却水 10, 16：給水管 11, 14：噴出口 1
2：角管 13：内壁 15：外壁 1
8：注湯ノズル 19：フロート 20：底台 2
1：スクリーン Ｍ：アルミ合金溶湯 Ｓ：鋳塊1: Mold 2: Cooling means
3: Wide surface 4: Short surface 5: Through hole
6: Partition wall 7: Header section 8: Mold section
9, 17: Cooling water 10, 16: Water supply pipe 11, 14: Spout 1
2: Square tube 13: Inner wall 15: Outer wall 1
8: Pouring nozzle 19: Float 20: Bottom stand 2
1: Screen M: Molten aluminum alloy S: Ingot
フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 ＦＩ 技術表示箇所 Ｂ２２Ｄ 11/22 Ｂ２２Ｄ 11/22 Ｂ (72)発明者 大下 浩 栃木県真岡市鬼怒ケ丘15番地 株式会社神 戸製鋼所真岡製造所内Continuation of front page (51) Int.Cl. 6 Identification number Reference number in the agency FI Technical indication B22D 11/22 B22D 11/22 B (72) Inventor Hiroshi Oshita 15 Kinugaoka, Moka-shi, Tochigi Co., Ltd. Kado Steel Works Moka Works
Claims (5)
制冷却鋳型の上部から導入し、鋳型により一次冷却して
凝固殻を形成せしめるとともに、凝固殻を形成した鋳塊
を強制冷却鋳型の下部から引き出し、その引き出されて
くる鋳塊表面に冷媒流体を直接当て二次冷却することに
より厚さ 300mm以上×幅1000mm以上の大矩形断面のアル
ミニウム合金スラブを鋳造するアルミニウム合金スラブ
の縦型連続鋳造方法において、鋳型広面部の中央部分か
らコーナー部に到る広面部の幅方向 1／3 〜 1／4 の長
さの両側方部分の冷却能を、広面部の中央部分の冷却能
に対し 0.8倍〜 1.5倍に設定して鋳型による一次冷却す
ることを特徴とするアルミニウム合金スラブの縦型連続
鋳造方法。1. A molten aluminum alloy is introduced from the upper part of a vertically open type forced cooling mold, and primary cooling is performed by the mold to form a solidified shell, and the ingot with the solidified shell is pulled out from the lower part of the forced cooling mold. In the vertical continuous casting method for aluminum alloy slabs, a large rectangular cross-section aluminum alloy slab with a thickness of 300 mm or more and a width of 1000 mm or more is cast by directly applying a refrigerant fluid to the surface of the ingot that is drawn out and performing secondary cooling. , The cooling capacity of both side parts of the width direction 1/3 to 1/4 of the width direction of the wide surface part from the central part of the mold wide surface part to the corner part is 0.8 times the cooling capacity of the central part of the wide surface part. A vertical continuous casting method for aluminum alloy slabs, which is characterized by setting 1.5 times and performing primary cooling by a mold.
却能の制御を、鋳型を冷却する冷媒流体の流量により行
う請求項１記載のアルミニウム合金スラブの縦型連続鋳
造方法。2. The vertical continuous casting method for an aluminum alloy slab according to claim 1, wherein the cooling ability of the central portion and both side portions of the wide surface portion of the mold is controlled by the flow rate of the refrigerant fluid for cooling the mold.
アルミニウム合金スラブの縦型連続鋳造方法。3. The vertical continuous casting method for an aluminum alloy slab according to claim 2, wherein the refrigerant fluid is cooling water.
面の二次冷却を、鋳型下方に設けた冷却手段により行う
請求項１記載のアルミニウム合金スラブの縦型連続鋳造
方法。4. The vertical continuous casting method for an aluminum alloy slab according to claim 1, wherein the secondary cooling of the surface of the ingot pulled out from the lower part of the mold is performed by a cooling means provided below the mold.
面の二次冷却を、鋳型の下部に直接設けられている二次
冷却手段に加えて鋳型下方に 100〜 500mm離して設けた
冷却手段により行うとともに、二次冷却手段における冷
媒流体量を冷却手段における冷媒流体量の 1／4 〜 3／
4 に設定して行う請求項１記載のアルミニウム合金スラ
ブの縦型連続鋳造方法。5. A secondary cooling means for directly cooling the surface of the ingot pulled out from the lower part of the mold, in addition to a secondary cooling means directly provided at the lower part of the mold, and a cooling means provided 100 to 500 mm apart below the mold. The amount of the refrigerant fluid in the secondary cooling means is set to 1/4 to 3 / of the amount of the refrigerant fluid in the cooling means.
The vertical continuous casting method for an aluminum alloy slab according to claim 1, which is performed by setting the number to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12455496A JP3458038B2 (en) | 1996-05-20 | 1996-05-20 | Vertical continuous casting method of aluminum alloy slab |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP12455496A JP3458038B2 (en) | 1996-05-20 | 1996-05-20 | Vertical continuous casting method of aluminum alloy slab |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH09308945A true JPH09308945A (en) | 1997-12-02 |
| JP3458038B2 JP3458038B2 (en) | 2003-10-20 |
Family
ID=14888361
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|---|---|---|---|
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| JP2003211255A (en) * | 2002-01-18 | 2003-07-29 | Sumitomo Light Metal Ind Ltd | Method for continuously casting aluminum cast block |
| JP2005028452A (en) * | 2003-06-18 | 2005-02-03 | Showa Denko Kk | CONTINUOUS CASTING METHOD OF Al-Mg-Si ALLOY AND Al-Mg-Si ALLOY INGOT, MANUFACTURING METHOD OF Al-Mg-Si ALLOY SHEET AND Al-Mg-Si ALLOY SHEET, AND MANUFACTURING METHOD OF HEAT RADIATION MATERIAL AND HEAT RADIATION MATERIAL |
| JP2017501887A (en) * | 2013-12-30 | 2017-01-19 | インテコ・スペシャル・メルティング・テクノロジーズ・ゲー・エム・ベー・ハーＩｎｔｅｃｏ Ｓｐｅｃｉａｌ Ｍｅｌｔｉｎｇ Ｔｅｃｈｎｏｌｏｇｉｅｓ ＧｍｂＨ | Manufacturing method and equipment for long ingot having large cross section |
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-
1996
- 1996-05-20 JP JP12455496A patent/JP3458038B2/en not_active Expired - Lifetime
Cited By (9)
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| JP2003211255A (en) * | 2002-01-18 | 2003-07-29 | Sumitomo Light Metal Ind Ltd | Method for continuously casting aluminum cast block |
| JP2005028452A (en) * | 2003-06-18 | 2005-02-03 | Showa Denko Kk | CONTINUOUS CASTING METHOD OF Al-Mg-Si ALLOY AND Al-Mg-Si ALLOY INGOT, MANUFACTURING METHOD OF Al-Mg-Si ALLOY SHEET AND Al-Mg-Si ALLOY SHEET, AND MANUFACTURING METHOD OF HEAT RADIATION MATERIAL AND HEAT RADIATION MATERIAL |
| JP2017501887A (en) * | 2013-12-30 | 2017-01-19 | インテコ・スペシャル・メルティング・テクノロジーズ・ゲー・エム・ベー・ハーＩｎｔｅｃｏ Ｓｐｅｃｉａｌ Ｍｅｌｔｉｎｇ Ｔｅｃｈｎｏｌｏｇｉｅｓ ＧｍｂＨ | Manufacturing method and equipment for long ingot having large cross section |
| CN108405821A (en) * | 2018-04-03 | 2018-08-17 | 东北大学 | The casting device and method of the big specification magnesium alloy slab ingot of flawless |
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| CN110479975A (en) * | 2019-08-02 | 2019-11-22 | 中铝材料应用研究院有限公司 | A kind of device of copper master alloy ingot casting |
| WO2021035604A1 (en) * | 2019-08-28 | 2021-03-04 | 东北大学 | Low-cold electromagnetic semi-continuous casting device and method |
| CN110842161A (en) * | 2019-10-28 | 2020-02-28 | 广东凤铝铝业有限公司 | Casting method of 2-series and 7-series aluminum alloy |
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| Publication number | Publication date |
|---|---|
| JP3458038B2 (en) | 2003-10-20 |
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