JPS6326239A - Mold for continuous casting of steel - Google Patents
Mold for continuous casting of steelInfo
- Publication number
- JPS6326239A JPS6326239A JP16689486A JP16689486A JPS6326239A JP S6326239 A JPS6326239 A JP S6326239A JP 16689486 A JP16689486 A JP 16689486A JP 16689486 A JP16689486 A JP 16689486A JP S6326239 A JPS6326239 A JP S6326239A
- Authority
- JP
- Japan
- Prior art keywords
- wall surface
- mold
- temp
- slab
- steel
- 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.)
- Granted
Links
- 238000009749 continuous casting Methods 0.000 title claims abstract description 24
- 229910000831 Steel Inorganic materials 0.000 title claims description 32
- 239000010959 steel Substances 0.000 title claims description 32
- 239000002826 coolant Substances 0.000 claims abstract description 29
- 238000005266 casting Methods 0.000 claims abstract description 9
- 238000007664 blowing Methods 0.000 claims abstract description 6
- 238000002347 injection Methods 0.000 claims description 5
- 239000007924 injection Substances 0.000 claims description 5
- 229910001566 austenite Inorganic materials 0.000 abstract description 51
- 238000001816 cooling Methods 0.000 abstract description 45
- 239000002344 surface layer Substances 0.000 abstract description 16
- 230000007547 defect Effects 0.000 abstract description 11
- 238000005098 hot rolling Methods 0.000 abstract description 6
- 238000000034 method Methods 0.000 abstract description 5
- 230000015572 biosynthetic process Effects 0.000 abstract description 2
- 238000005336 cracking Methods 0.000 description 17
- 239000000203 mixture Substances 0.000 description 12
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 9
- 230000000694 effects Effects 0.000 description 8
- 238000007711 solidification Methods 0.000 description 8
- 230000008023 solidification Effects 0.000 description 8
- 238000004519 manufacturing process Methods 0.000 description 6
- 238000010791 quenching Methods 0.000 description 6
- 230000000171 quenching effect Effects 0.000 description 6
- 238000005096 rolling process Methods 0.000 description 6
- 230000005499 meniscus Effects 0.000 description 5
- 239000002436 steel type Substances 0.000 description 5
- 229910000975 Carbon steel Inorganic materials 0.000 description 4
- 229910017112 Fe—C Inorganic materials 0.000 description 4
- 239000000498 cooling water Substances 0.000 description 4
- 238000010587 phase diagram Methods 0.000 description 4
- 239000002244 precipitate Substances 0.000 description 4
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000002245 particle Substances 0.000 description 3
- 238000005204 segregation Methods 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 238000005452 bending Methods 0.000 description 2
- 239000010962 carbon steel Substances 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 239000004615 ingredient Substances 0.000 description 2
- 239000010410 layer Substances 0.000 description 2
- 150000004767 nitrides Chemical class 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 230000008646 thermal stress Effects 0.000 description 2
- 150000003568 thioethers Chemical class 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000005275 alloying Methods 0.000 description 1
- 238000009529 body temperature measurement Methods 0.000 description 1
- 229910052799 carbon Inorganic materials 0.000 description 1
- 230000015271 coagulation Effects 0.000 description 1
- 238000005345 coagulation Methods 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 238000012790 confirmation Methods 0.000 description 1
- 239000000112 cooling gas Substances 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 230000000368 destabilizing effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000005242 forging Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 238000001000 micrograph Methods 0.000 description 1
- 238000009740 moulding (composite fabrication) Methods 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000001556 precipitation Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000003303 reheating Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/16—Controlling or regulating processes or operations
- B22D11/22—Controlling or regulating processes or operations for cooling cast stock or mould
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Continuous Casting (AREA)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
この発明は、連続鋳造によって製造された鋳片を熱間圧
延する際に生じがちな、オーステナイト粒界に沿って伝
播する表面疵を抑制し、表面性状の良好な熱間加工鋼材
を安定して製造する方法に関するものである。[Detailed Description of the Invention] <Industrial Application Field> The present invention suppresses surface flaws that propagate along austenite grain boundaries, which tend to occur when hot rolling slabs manufactured by continuous casting. , relates to a method for stably producing hot-worked steel materials with good surface properties.
く背景技術〉
近年、鉄鋼の製造に当たっては、垂直型若しくは湾曲型
の連続鋳造機を使用した連続鋳造工程が不可欠なものと
なっているが、このような連続鋳造法によってブルーム
やスラブ等の鋳片を製造しようとすると、その鋳造の途
中で鋳片に加わる熱応力や曲げ応力によって表面疵(表
面割れ)が発生し、これを熱間直送圧延(連続鋳造で得
た鋳片を加熱することなく直ちに実施する圧延)又はホ
ントチャージ圧延(連続鋳造で得た鋳片を室温にまで冷
却することなく再加熱して実施する圧延)しようとする
と、前記表面疵がそのまま圧延工程にまで持ち来たされ
て割れ疵が一層助長されると言う不都合があり、また連
続鋳造鋳片に通常の熱間加工(−旦常温にまで冷却した
鋳片を再加熱して行う熱1??1鍛造や熱間圧延)を施
す場合でも表面疵を発生し易いと言う問題が目立ち、表
面性状の良好な熱間加工鋼材を製造する上で大きな障害
となっていた。Background technology In recent years, continuous casting processes using vertical or curved continuous casting machines have become indispensable in the production of steel. When trying to manufacture slabs, surface flaws (surface cracks) occur due to thermal stress and bending stress applied to the slab during casting, and these can be removed by direct hot rolling (heating the slab obtained by continuous casting). When attempting to perform real charge rolling (rolling performed immediately without cooling the slab obtained by continuous casting to room temperature), the surface flaws were carried over into the rolling process. There is also the disadvantage that continuous casting slabs are subjected to normal hot working (heat 1??1 forging, which is performed by reheating slabs that have been cooled to room temperature). Even when rolling), the problem of easy occurrence of surface defects is noticeable, and this has been a major obstacle in producing hot-worked steel materials with good surface properties.
ところで、上述のような表面疵の発生状況を調査してみ
るといずれもオーフチナイト(γ)粒界の割れを伴って
起きることが観察されることから、従来、前記表面疵の
発生原因の1つとして「鋳片の凝固・冷却中にオーステ
ナイト(γ)粒界へ析出又は偏析する炭化物や窒化物(
NbC1AIN等)、(Mn、Fe) S等の硫化物、
並びにPやS等の不純物元素が結晶粒界の脆弱化を招く
」ことが挙げられるようになり、表面疵(割れ)の発生
穎度は、上記の如き析出物や偏析を生じさせる元素の含
有量に大きく影響されることが知られるようになってき
た。By the way, when we investigate the occurrence of the above-mentioned surface flaws, we find that they occur together with cracking of auftinite (γ) grain boundaries. ``Carbides and nitrides that precipitate or segregate to austenite (γ) grain boundaries during solidification and cooling of slabs (
NbC1AIN, etc.), sulfides such as (Mn, Fe)S,
In addition, impurity elements such as P and S cause weakening of grain boundaries.''The degree of purity of surface defects (cracks) is determined by the presence of elements that cause the above-mentioned precipitates and segregation. It has come to be known that the amount is greatly affected.
そこで、このような元素の含有量を制御することによっ
て鋳片の表面疵防止を図る試みもなされたが、この場合
には、製品の品質(特性)確保やコスト面で限界がある
上、化学成分の調整基準が今一つ明確でなく、従って化
学成分の調整のみでは十分に満足できる効果を挙げ得な
かったのである。Therefore, attempts have been made to prevent surface defects in slabs by controlling the content of these elements, but in this case, there are limitations in terms of ensuring product quality (characteristics) and cost, and chemical The standards for adjusting the ingredients were not very clear, and therefore, adjusting the chemical ingredients alone was not enough to achieve a satisfactory effect.
一方、かかる鋳片表面疵の発生頻度は、第3図で示され
るように鋳片のC含有量に大きく依存すると言う事実も
あるが、その原因は未だに不明であり、これに対する何
らの方策も見つからないこともあって、結局はこのよう
なC含有量領域を避けて操業が行われることすらあった
。On the other hand, as shown in Figure 3, the frequency of occurrence of surface defects on slabs is largely dependent on the C content of slabs, but the cause is still unknown and no countermeasures have been taken. In some cases, they were unable to find it, and in the end, operations were even carried out avoiding such C content regions.
しかしながら、第3図にみられるような表面疵発生頻度
が急激に高くなる領域は必ずしも一定していないで、鋼
種によってもバラツキがあり、特に低合金鋼の場合には
C含有量から推し量れないような思いがけない成分組成
領域で表面きず発生頻度が極端に高くなることが多く、
しばしば、操業上極めて不都合な結果を招(自体がもた
らされていたのである。However, as shown in Figure 3, the region where the frequency of surface flaws increases rapidly is not necessarily constant, and varies depending on the steel type, and especially in the case of low-alloy steel, it cannot be estimated from the C content. Surface flaws often occur at an extremely high frequency in unexpected component composition regions that are unlikely to occur.
This often led to extremely inconvenient operational results.
従って、従来一般に実施されている表面疵防止対策は、
オシレーションマークを浅くしたり、凝固シェルに作用
する熱応力を軽減したりするために鋳片の冷却速度を小
さくすると言った不十分なものでしかなかった。Therefore, the surface flaw prevention measures commonly implemented in the past are as follows:
In order to make the oscillation mark shallower and to reduce the thermal stress acting on the solidified shell, the cooling rate of the slab was reduced, which was insufficient.
このようなことから、鋼の連続鋳造や、これに次いで実
施される熱間圧延において鋳片表面に割れ疵が発生する
のを確実に防止し、表面性状の良好な熱間加工鋼材を工
業的に量産し得る手段の出現が強く望まれているのが現
状であった。For this reason, it is necessary to reliably prevent cracks from occurring on the surface of the slab during continuous casting of steel and subsequent hot rolling, and to produce hot-processed steel materials with good surface properties for industrial use. At present, there is a strong desire for the emergence of a means for mass production.
く研究によって明らかとなった事項〉
本発明者等は、上述のような観点から、連続鋳造によっ
て製造される鋼鋳片の鋳造途中における表面疵発生や、
連続鋳造鋳片を熱間加工する際に起こりがちな表面疵の
発生を確実に防止する実施容易な手段を見出すべく、そ
のためには、第3図で示したような特定C含有it 9
i域近傍での表面疵発生頻度急増の原因解明が不可欠で
あるとの考えの下に種々の実験・研究を重ねたところ、
次に示すような知見を得たのである。即ち、
(a) 連続鋳造鋳片の結晶粒界割れは、従来言われ
ていたように、結晶粒界に析出又は偏析する炭化物、窒
化物、硫化物或いは不純物等に係る元素の含fffiに
影響されることもさることながら、これらの析出や偏析
密度を左右するオーステナイト(y)粒の粒度に大きく
影響され、凝固・冷却中のオーステナイト(γ)粒の粗
大化は鋳片の粒界割れを著しく助長すること。From the above-mentioned viewpoints, the present inventors have investigated the occurrence of surface flaws during casting of steel slabs manufactured by continuous casting,
In order to find an easy-to-implement means to reliably prevent the occurrence of surface flaws that tend to occur when hot working continuously cast slabs, it is necessary to use specific C-containing it 9 as shown in Figure 3.
Based on the idea that it is essential to elucidate the cause of the rapid increase in the frequency of surface flaws occurring near area i, we have conducted various experiments and research.
The following findings were obtained. That is, (a) Grain boundary cracking in continuously cast slabs, as previously said, affects the content of elements such as carbides, nitrides, sulfides, or impurities that precipitate or segregate at grain boundaries. In addition to this, the grain size of austenite (y) grains, which influences the precipitation and segregation density, is greatly affected, and the coarsening of austenite (γ) grains during solidification and cooling can cause intergranular cracking in slabs. To significantly facilitate.
(bl 凝固・冷却中の炭素鋼鋳片のオーステナイト
(γ)粒粗大化の程度はそのC含有量の変化によって大
きく変わり、それもC含有量との単なる比例的関係を維
持しながら変化するわけではなく、第4図で示されるよ
うに、前述した表面疵を発生し易いC含有ISM域で急
激に著しくなると言う挙動を示すこと(因に、第4図は
Fe−C系鋼の凝固・冷却中に冷却速度を5℃/sec
としたときの、C含有量とオーステナイト粒径との関係
を示す曲線である)。(bl) The degree of austenite (γ) grain coarsening in a carbon steel slab during solidification and cooling varies greatly depending on changes in its C content, and it also changes while maintaining a simple proportional relationship with the C content. Rather, as shown in Fig. 4, the above-mentioned behavior shows a behavior that suddenly becomes more pronounced in the C-containing ISM region where surface flaws are likely to occur. During cooling, set the cooling rate to 5℃/sec.
This is a curve showing the relationship between C content and austenite grain size when
(C) これらの結果と、「凝固・冷却中のオーステ
ナイト(γ)粒の粗大化は、オーステナイト単相となっ
てから急激に起こり、しかも温度が高いほどその傾向が
著しい」と言う実験による確認事項とからみて、凝固・
冷却中の炭素鋼鋳片は、同一冷却条件下であると、必然
的に、第5図で示されるFe−C系平衡状態図からも明
らかな“オーステナイト単相化温度が最も高い組成のも
の”、即ち“包晶点組成(Fe−C系では0.18重量
%C)のもの”が最も粗大なオーステナイトD)粒を呈
するようになり(因に、第5図中の破線は第4図で示し
たオーステナイト粒粗大化挙動を表わす)、従って熱間
割れ感受性もこの付近のものが急激に高くなると結論さ
れること。(C) These results and experimental confirmation that ``the coarsening of austenite (γ) grains during solidification and cooling occurs rapidly after becoming austenite single phase, and the higher the temperature, the more remarkable this tendency is.'' In view of the above, coagulation and
Under the same cooling conditions, a carbon steel slab being cooled will inevitably have a composition with the highest austenite single-phase temperature, which is clear from the Fe-C system equilibrium phase diagram shown in Figure 5. ”, that is, “those with a peritectic point composition (0.18 wt. (This shows the austenite grain coarsening behavior shown in the figure.) Therefore, it can be concluded that the hot cracking susceptibility increases rapidly near this area.
(dl ところで、第4図で示されるオーステナイト
(γ)粒径粗大化挙動と第3図で示される鋳片表面疵発
生頻度傾向とは必ずしも合致していない。(dl) By the way, the austenite (γ) grain size coarsening behavior shown in FIG. 4 does not necessarily match the frequency trend of occurrence of defects on the slab surface shown in FIG. 3.
しかしながら、これは、第4図が純粋なFe−C系での
実験結果であるのに対して第3図は実用鋼の場合のデー
タであると言う相違に起因するものであり、C以外の含
有元素(合金元素等)の影響によって包晶点がずれてい
るからに他ならないこと。However, this is due to the difference that Figure 4 shows the experimental results for pure Fe-C system, while Figure 3 shows the data for practical steel. This is simply because the peritectic point is shifted due to the influence of the contained elements (alloy elements, etc.).
(e)シかも、鋼中に含有されるC以外の元素の種類に
よっては、鋼の熱間割れ感受性か−N鋭敏化し、鋳片表
面疵の増大を招く恐れがあること。(e) Depending on the type of elements other than C contained in the steel, the hot cracking sensitivity of the steel may become more sensitive to -N, which may lead to an increase in flaws on the surface of the slab.
(f) 従って、鋳片の熱間割れ感受性を評価する場
合には、C含有量のみでなく、合金元素の影響をも含め
たC当量(Cp)を指標にする必要があること。(f) Therefore, when evaluating the hot cracking susceptibility of a slab, it is necessary to use not only the C content but also the C equivalent (Cp), which includes the influence of alloying elements, as an index.
fg) 状態図的な検討から鋼の包晶点に影響を及ぼ
すと考えられる元素として、C5Mn5 Ni、 Cu
及びNが挙げられ、C当量(Cp)は次式で整理される
こと(なお、以下、成分割合を表わす%は重量%とする
)。即ち、
(h) 状態図的検討によって得られた上記式は実際
と良く合致しており、これに基づいて鋳片の熱間割れ感
受性を極めて的確に評価できること。fg) From a phase diagram study, elements that are thought to affect the peritectic point of steel include C5Mn5 Ni, Cu
and N, and the C equivalent (Cp) is expressed by the following formula (hereinafter, % representing the component ratio is expressed as weight %). That is, (h) the above formula obtained by phase diagram examination agrees well with reality, and based on this, the hot cracking susceptibility of the slab can be evaluated very accurately.
第6図は、これを確認するために本発明者等が実施した
実験結果を示すものであり、第1表に示される成分組成
内の合計50種類の鋼から採取した小片をアルミするつ
ぼ中で再溶解した後、冷却速度:5℃/secで冷却し
、そのオーステナイト粒径を測定して上記式で算出され
るCp値により整理したグラフである。Figure 6 shows the results of an experiment carried out by the inventors to confirm this, in which small pieces collected from a total of 50 types of steel within the composition shown in Table 1 were made into aluminum pots. This is a graph in which the austenite grain size was measured after remelting at a cooling rate of 5° C./sec and organized by the Cp value calculated by the above formula.
この第6図からも明らかなように、オーステナイl−(
r)粒径はCp値で良く整理され、Cp値が0.18で
最大値をとることがわかる。As is clear from Fig. 6, austenite l-(
r) It can be seen that the particle size is well organized by Cp value, and takes the maximum value at Cp value of 0.18.
(1) 上記の如くにオーステナイト(γ)粒径がC
p値に左右される理由は、オーステナイト単相化温度(
TT)がCp値の変化に追随して同様傾向で変化し、該
値により決定されるからであり、例えばCp値が特定の
値(0,18、即ち包晶点)のときにオーステナイト(
γ)粒径が最大値となるのは、該Cp値のときにオース
テナイト単相化温度(TT)が最も高くなって冷却過程
でのオーステナイト(γ)粒成長期間も最長となり、粗
大化の機会が十分に与えられるからであること。(1) As mentioned above, the austenite (γ) grain size is C
The reason why it depends on the p value is the austenite single phase temperature (
This is because TT) changes with the same tendency as the Cp value changes and is determined by this value. For example, when the Cp value is a specific value (0, 18, peritectic point), austenite (
γ) The grain size reaches its maximum value because at the Cp value, the austenite single-phase temperature (TT) is the highest and the austenite (γ) grain growth period during the cooling process is also the longest, creating an opportunity for coarsening. This is because they are given enough.
このことは、先に示した第5図からも推測されることで
はあるが、次に示す第7図を参照されたい。Although this can be inferred from FIG. 5 shown above, please refer to FIG. 7 shown below.
第7図は、第1表に示される成分組成内の合計50種類
の綱から採取した小片をアルミするつぼ中で再溶解した
後、冷却速度:0.1℃/sec及び2.0℃/se<
:で冷却し、そのオーステナイト単相化温度(TT)を
測定して前記式で算出されるCp値により整理したグラ
フであるが、この第5図からも明らかな如く、冷却速度
が0.1〜2.0℃/secの範囲ではオーステナイト
単相化温度(TT)はCp値によって良く整理されて次
式のように表され、Cp値が0.18で最大値を採るこ
とが分かる。Figure 7 shows that small pieces collected from a total of 50 kinds of ropes with the component composition shown in Table 1 were remelted in an aluminum crucible, and then the cooling rate was 0.1°C/sec and 2.0°C/sec. se<
This is a graph organized by the Cp value calculated by the above formula by measuring the austenite single phase temperature (TT) after cooling at It can be seen that in the range of ~2.0° C./sec, the austenite single phase temperature (TT) is well-organized by the Cp value and expressed as the following equation, and takes the maximum value when the Cp value is 0.18.
Tγ=ACp+B
しかも、第2表に示される成分組成の鋼について“オー
ステナイト単相化温度(Tr)に及ぼす冷却速度の影響
”を調査した第8図からは、「冷却速度が2.0℃/s
ec以上であってもオーステナイト単相化温度(TT)
は殆ど変化しない」ことが確認でき、冷却速度が前記範
囲より大きい場合でも、オーステナイト単相化温度(T
’γ)は上記式により実質的にCp値にのみ依存した値
として算出されることが明瞭である。Tγ=ACp+B Furthermore, from Figure 8, which investigated the "influence of cooling rate on austenite single phase temperature (Tr)" for steels with the compositions shown in Table 2, it is clear that "the cooling rate is 2.0℃/ s
Austenite single phase temperature (TT) even if it is above ec
It was confirmed that "there is almost no change in the austenite single phase temperature (T
It is clear that 'γ) is calculated by the above formula as a value that substantially depends only on the Cp value.
0) また一方、同一組成鋼を凝固・冷却した場合の
鋳片のオーステナイト(γ)粒径は、Cp値(即ち“T
T”)に影響されることもさることながら高A領域での
冷却速度に大きく左右され、特にオーステナイト単相化
温度(Tr)から約1000℃に至るまでの温度領域に
おける冷却速度によってほぼ決定されてしまうこと。0) On the other hand, when steel of the same composition is solidified and cooled, the austenite (γ) grain size of the slab is determined by the Cp value (i.e., “T
In addition to being influenced by T"), it is also greatly influenced by the cooling rate in the high A range, and in particular, it is almost determined by the cooling rate in the temperature range from the austenite single phase temperature (Tr) to about 1000°C. To be left behind.
第9図は、各種C含有量の炭素鋼を溶解してから冷却速
度70.28℃/secで冷却するとともに、その途中
から水焼入れして組織を固定したものについて、該水焼
入れ温度とオーステナイト(γ)粒径との関係をプロ・
ノドしたグラフである。また、第10図はTT@後の組
織の一例であり、0.15%C−1,48%Mn@を0
.1℃/secで冷却した場合の顕微鏡組織を示したも
のであって、第10図(a)は1470℃(TT+5℃
)から水焼入れしたもの、そして第10図(b)は14
60℃(T r −5℃)から水焼入れしたものをそれ
ぞれ示しているが、この図はTγ直後からγ粒が急激に
粗大化し始めることが分かる。更に、第9図及び第10
図から、急冷がオーステナイト(T)粒成長に大きく影
響するのは極く高い温度域、特にオーステナイト単相化
温度(TT)から1000℃までの温度域に限られ、そ
れよりも低い温度域では急冷の影響はそれほど顕著でな
くなることが明らかである。Figure 9 shows the water quenching temperature and austenite of carbon steels with various C contents that were melted and then cooled at a cooling rate of 70.28°C/sec, and then water quenched midway through to fix the structure. (γ) The relationship with particle size is
This is a rough graph. Figure 10 is an example of the structure after TT@, and 0.15%C-1,48%Mn@
.. Figure 10(a) shows the microscopic structure when cooled at 1°C/sec at 1470°C (TT+5°C).
) and water quenched from ), and Figure 10(b) is 14
The graphs show the results of water quenching from 60°C (T r -5°C), and it can be seen that the γ grains begin to coarsen rapidly immediately after Tγ. Furthermore, Figures 9 and 10
The figure shows that quenching has a large effect on austenite (T) grain growth only in extremely high temperature ranges, especially in the temperature range from the austenite single phase temperature (TT) to 1000°C, and in lower temperature ranges. It is clear that the effect of rapid cooling becomes less pronounced.
そして、加えて第11図を参照されたい。第11図は、
第1表に示される成分組成内の合計30種の鋼について
オーステナイト単相化温度(TT)以降の冷却速度を種
々に変え、1000℃に到達後急冷してその組織を固定
したもののオーステナイト(γ)粒径を前記冷却速度で
整理して表したグラフである。この第11図からは、オ
ーステナイト単相化温度(Tr)が最も高くてオーステ
ナイト粒が粗大化し易い包晶組成(Cp =0.18)
の鋼であったとしても、オーステナイト単相化温度(T
T)以降の冷却速度を大きくしてやれば該オーステナイ
ト単相化温度(TT)よりも高い温度域での冷却速度に
かかわらずオーステナイト(γ)粒の粗大化を防止でき
ることが分かる。In addition, please refer to FIG. 11. Figure 11 shows
For a total of 30 types of steel with the composition shown in Table 1, the cooling rate after the austenite single-phase temperature (TT) was varied, and after reaching 1000°C, the structure was rapidly cooled to fix the austenite (γ ) is a graph illustrating particle diameters organized by the cooling rate. From this Figure 11, the peritectic composition (Cp = 0.18) where the austenite single phase temperature (Tr) is the highest and the austenite grains tend to become coarser is found.
Even if the steel is austenite single phase temperature (T
It can be seen that if the cooling rate after T) is increased, coarsening of austenite (γ) grains can be prevented regardless of the cooling rate in a temperature range higher than the austenite single-phase temperature (TT).
(k) ところで、連続鋳造途中の鋳片の表面割れ傾
向や、連続鋳造に引き続いて行われる熱間直送圧延又は
ホットチャージ圧延での鋼片の表面割れ傾向は、連続鋳
造鋼片表層部(表面から3mm程度、多くとも10龍)
の割れ感受性によって決まってくること。(k) By the way, the tendency of surface cracking of a slab during continuous casting, or the tendency of surface cracking of a slab during hot direct rolling or hot charge rolling that is performed subsequent to continuous casting, is determined by the surface cracking tendency of a slab during continuous casting. (about 3 mm, at most 10 dragons)
Determined by the cracking sensitivity of
(1)従って、包晶組成付近の鋳片であってもオーステ
ナイト単相化温度(Tr)以降の表層部冷却速度を大き
くすると、該表層部におけるオーステナイト粒の粗大化
が抑制されて単位体積当たりの結晶粒界面積の大きい細
結晶粒組織が得られるようになり、このため結晶粒界に
集まる析出物や偏析の密度が低くなって割れ感受性が緩
和されるとともに靭性も高くなるので、前記表面割れの
恐れが払拭されてしまうこと。(1) Therefore, even for slabs with a peritectic composition, if the cooling rate of the surface layer after the austenite single phase temperature (Tr) is increased, the coarsening of austenite grains in the surface layer is suppressed and A fine grain structure with a large grain boundary area can be obtained, which lowers the density of precipitates and segregation that gather at grain boundaries, reducing cracking susceptibility and increasing toughness. The fear of cracking is eliminated.
(m) このようなことから、連続鋳造によって製造
される鋳片の鋳造途中における表面疵(割れ)発生や、
連続鋳造鋳片を熱間圧延する際の表面疵(割れ)発生傾
向の強い鋼種を前記式(Cp値を算出する式)によって
簡単・確実に予測することが可能であり、また、これら
の鋼種についても、鋳片の表層部が特定の高温度域(実
際には“Tr”以上を目安にすれば良い)である間に急
冷処理(表層部の冷却速度:10℃/sec以上での冷
却)することにより表面疵発生を安定して抑えることが
可能であること。(m) For this reason, surface flaws (cracks) may occur during casting of slabs manufactured by continuous casting,
It is possible to easily and reliably predict steel types with a strong tendency to generate surface flaws (cracks) when continuously cast slabs are hot-rolled using the above formula (formula for calculating Cp value), and also to predict these steel types. Also, while the surface layer of the slab is in a specific high temperature range (actually, it is sufficient to aim for "Tr" or higher), rapid cooling treatment (cooling rate of the surface layer: 10℃/sec or higher) is performed. ), it is possible to stably suppress the occurrence of surface defects.
そこで、本発明者等はこれら(al〜+m)に示した知
見事項に基づいて、鋳型内に注入した溶鋼の高温域にお
ける冷却速度を速くすることで表面割れ感受性の低い鋳
片を製造しようとの試みを行ったが、鋼の連続鋳造の実
操業においては、−溶鋼メニスカス近傍では凝固シェル
と鋳型壁とが溶融パウダーを介して密着した状態で凝固
が進行するものの、それより下方になると溶鋼の凝固収
縮と鋳片の温度降下に伴う収縮とで鋳片は鋳型壁面から
離れて、鋳型の抜熱作用を損なうエアーギャップを生じ
るようになり、従って、垂直型又は湾曲型連続鋳造機で
使用される通常の鋳型(長さが700〜900flかそ
れ以上)では、その後にオーステナイト粒界破壊を起こ
して表面疵を発生し易くなる程度にまでオーステナイト
粒の粗大化をもたらすような著しい冷却遅れが生じるの
を免れることができないとの問題に突き当ったのである
。Therefore, based on the findings shown in (al~+m), the present inventors attempted to manufacture slabs with low surface crack susceptibility by increasing the cooling rate in the high temperature range of molten steel injected into the mold. However, in actual continuous steel casting operations, solidification progresses near the molten steel meniscus with the solidified shell and mold wall in close contact with each other via the molten powder, but below that point, the molten steel Due to the solidification shrinkage of the slab and the shrinkage caused by the temperature drop of the slab, the slab separates from the mold wall, creating an air gap that impairs the heat removal effect of the mold. In conventional molds (700 to 900 fl or more in length), there is a significant cooling delay that causes the austenite grains to coarsen to the extent that subsequent austenite grain boundary fracture occurs and surface defects are more likely to occur. We have run into a problem that cannot be avoided.
このため、鋳型の長さを短くして、鋳型内での溶鋼の凝
固は極く薄い鋳片表面凝固層の形成だけに止め、鋳型下
端から早めに引き抜いた鋳片に冷却媒体を吹き付けるこ
とで高温度域での冷却速度を高めることも試みたが、こ
の場合には鋳片のブレークアウトを引き起こす危険が極
めて高く、実曳業上好ましい手段ではなかった。Therefore, by shortening the length of the mold, the solidification of the molten steel in the mold is limited to the formation of an extremely thin solidified layer on the surface of the slab, and a cooling medium is sprayed onto the slab that is pulled out from the bottom of the mold early. Attempts were also made to increase the cooling rate in the high temperature range, but in this case there was an extremely high risk of causing breakout of the slab, and this was not a desirable measure in practical towing operations.
く問題点を解決するための手段〉
この発明は、以上に説明した問題点を踏まえた上で、鋼
の成分組成に影響されることなく、表面割れ感受性の小
さい連続鋳造鋳片を安定かつ生産性良く製造する手段を
提供しようとしてなされたもので、
鋼の連続鋳造用両端開放鋳型を、 第1図に示されるよ
うに、鋳型1の下部内壁面2に鋳片表層部温度測定用の
検温センサー3と冷却媒体吹き込み用ノズル孔4とを配
設し、かつ該下部内壁面2の上方に冷却媒体吸引用導通
孔6を設けることにより、下部4内壁面に達した鋳片表
層部の温度が先に述べた適正な範囲(“Tr”以上の急
冷効果が期待できる範囲)であるか否かを検温センサー
3にて検知するとともに、適正温度域にある鋳片表層部
を10℃/sec以上の冷却速度で冷却できるように検
温センサー3を通じて冷却媒体吹き込み用ノズル孔4か
らの冷却媒体吹き込み量を調節し得るようにし、かつ、
吹き込まれた冷却媒体が鋳型1の上部内壁面5と溶鋼7
のメニスカス8との間に間隙を作ってそこから上方に吹
き抜け、メニスカス8近傍の冷却を不安定化するのを冷
却媒体吸引用導通孔6からのスムーズな排出により確実
に防止できるようにするか、 或いは、第2図に示され
るように、これらに加えて鋳片表層部温度測定用の検温
センサー3と冷却媒体吹き込み用ノズル孔4とが配設さ
れた鋳型1の下部内壁面2を上部内壁面5よりも後退さ
せることで、冷却媒体による冷却効果とその均一性を更
に増すとともに(鋳片表面と下部内壁面との間でエアー
や冷却媒体が部分的に留まるのが確実に防止されるため
である)、冷却媒体吸引用導通孔6からの冷却媒体の吸
引を容易にして吸引能力を高め得るようにするかした構
造とすることによって、鋳込まれた溶鋼の高温での高い
冷却速度が容易に確保される上、鋳片ブレークアウトに
よる危険を確実に回避できるようにし、鋼種に影響され
ることなく、表面疵のない、しかも表面割れ感受性の低
い連続鋳造鋳片を安定して量産し得るようにした点、に
特徴を有するものである。Means for Solving the Problems> Based on the problems explained above, the present invention provides a method for stably producing continuously cast slabs with low surface crack susceptibility, without being affected by the chemical composition of steel. This was done in an attempt to provide a means for manufacturing with high efficiency.As shown in Fig. 1, a mold with both ends open for continuous casting of steel was equipped with a thermometer on the lower inner wall surface 2 of the mold 1 to measure the temperature of the surface layer of the slab. By arranging a sensor 3 and a nozzle hole 4 for blowing a cooling medium, and providing a passage hole 6 for sucking a cooling medium above the lower inner wall surface 2, the temperature of the surface layer of the slab that has reached the inner wall surface of the lower part 4 can be adjusted. The temperature sensor 3 detects whether or not the temperature is within the appropriate range mentioned above (the range in which a rapid cooling effect higher than "Tr" can be expected), and the surface layer of the slab in the appropriate temperature range is heated at 10°C/sec. The amount of cooling medium blown from the cooling medium injection nozzle hole 4 can be adjusted through the temperature measurement sensor 3 so that cooling can be performed at the above cooling rate, and
The coolant blown into the upper inner wall surface 5 of the mold 1 and the molten steel 7
By creating a gap between the coolant and the meniscus 8 and blowing upward from there, destabilizing the cooling in the vicinity of the meniscus 8, can be reliably prevented by smooth discharge from the coolant suction passage hole 6. Alternatively, as shown in FIG. 2, the lower inner wall surface 2 of the mold 1, which is provided with a temperature sensor 3 for measuring the temperature of the surface layer of the cast slab and a nozzle hole 4 for blowing a cooling medium, is removed from the upper surface. By setting it back from the inner wall surface 5, the cooling effect and uniformity of the cooling medium is further increased (it is reliably prevented that air or the cooling medium remains partially between the slab surface and the lower inner wall surface). The structure is designed to facilitate the suction of the cooling medium from the cooling medium suction passage hole 6 and increase the suction capacity, thereby achieving high cooling of the cast molten steel at high temperatures. Not only can the speed be easily ensured, but the danger of slab breakout can be reliably avoided, and continuous casting slabs with no surface flaws and low susceptibility to surface cracking can be stably produced without being affected by the steel type. It is characterized by the fact that it can be mass-produced.
なお、第1図及び第2図において、符号9は凝固シェル
を、符号10は冷却水通路を、そして符号11は冷却水
スプレーノズルをそれぞれ示している。In FIGS. 1 and 2, reference numeral 9 indicates a solidified shell, reference numeral 10 indicates a cooling water passage, and reference numeral 11 indicates a cooling water spray nozzle.
さて、第1図において、鋳型1中に溶@7が鋳込まれる
と、まず鋳型の上部内壁面5の抜熱作用によって極く薄
い凝固シェルが形成されるが、この上部内壁面5の長さ
を例えば500 m+s程度(メニスカス下の長さ:3
00龍程度)と極く短か(しておくと、鋳片の凝固シェ
ルが形成されたばかりの部分は直ちに下部内壁面2の位
置にまで降下されることとなり、冷却媒体吹き込み用ノ
ズル孔4から吹き込まれて冷却媒体吸引用導通孔6へと
還流する冷却媒体(例えばl(eガス等)によって効率
良く冷却されるので(先に述べた如く、第2図のように
下部内壁面2が後退した鋳型の場合には冷却効率が一層
向上する)、従来の両端開放鋳型におけるような、“凝
固や冷却による収縮のために凝固シェル面が鋳型内壁面
から離れて両面間に空気層を形成し、これによって冷却
遅れを生じる”と言う不都合を来たすことがない。しか
も、検温センサー3により急冷開始鋳片の表層部温度を
正確に確認することができる上、冷却速度の調整も容易
となり、従って鋳片表層部の高温度域における高い冷却
速度が安定に確保されるので、該表層部におけるオース
テナイト粒の粗大化を確実に防止でき、表面疵の無い、
そして表面割れ感受性の低い鋳片を効率良く製造するこ
とができる。Now, in Fig. 1, when the molten @7 is poured into the mold 1, an extremely thin solidified shell is formed by the heat removal action of the upper inner wall surface 5 of the mold. For example, about 500 m+s (length below the meniscus: 3
If this is done, the part of the slab where the solidified shell has just been formed will be immediately lowered to the position of the lower inner wall surface 2, and the cooling medium injection nozzle hole 4 will be The cooling medium (e.g., e-gas, etc.) that is blown in and flows back into the cooling medium suction passage hole 6 efficiently cools the body (as mentioned earlier, the lower inner wall surface 2 recedes as shown in FIG. 2). (The cooling efficiency is further improved in the case of molds with open ends.) Unlike conventional molds with both ends open, the solidified shell surface separates from the inner wall surface of the mold due to shrinkage due to solidification and cooling, forming an air layer between both surfaces. In addition, the temperature sensor 3 allows the temperature of the surface layer of the slab to be rapidly cooled to be accurately confirmed, and the cooling rate can be easily adjusted. Since a high cooling rate is stably maintained in the high temperature range of the surface layer of the slab, it is possible to reliably prevent coarsening of austenite grains in the surface layer, resulting in no surface flaws.
And slabs with low surface crack susceptibility can be efficiently produced.
また、このような鋳型であれば、所望厚の凝固シェルが
形成されるまでの鋳片部分を鋳型内に止。In addition, with such a mold, the slab remains in the mold until a solidified shell of the desired thickness is formed.
めでおくことができるので、ブレークアウトによる危険
が生じることもない。Since it can be safely stored, there is no risk of breakout.
冷却媒体吹き込み用ノズル孔4から吹き込む冷却媒体と
しては、Heガス等の冷却ガスのほか、これらと水との
混合ガス等を採用することもできる。As the cooling medium injected from the cooling medium injection nozzle hole 4, in addition to cooling gas such as He gas, a mixed gas of these and water can also be employed.
次に、この発明を実施例により比較例と対比しながら説
明する。Next, the present invention will be explained using examples and comparing with comparative examples.
〈実施例〉
実施例 l
第3表に示されるところの、成分的には連続鋳造鋳片に
表面疵が多発し易いAIを溶解し、第1図で示されるよ
うな本発明に係る水冷銅鋳型(形状と寸法を第4表に示
す。第2図で示される鋳型については下部内壁面が上部
内壁面よりも2龍後退しているほかは第1図と同様であ
る)と、従来の水冷銅鋳型(全長:800m+*)を取
り付けた実用の湾曲型連続鋳造機(湾曲半径:12.5
m)によって、断面寸法が250mX1200mmのス
ラブを鋳造速度: 1.2m/minにて約150m
製造した。<Example> Example 1 The water-cooled copper according to the present invention as shown in FIG. The mold (the shape and dimensions are shown in Table 4. The mold shown in Figure 2 is the same as that in Figure 1 except that the lower inner wall surface is set back two inches from the upper inner wall surface) and the conventional mold. Practical curved continuous casting machine (bending radius: 12.5
m), a slab with cross-sectional dimensions of 250 m x 1200 mm is cast at a casting speed of about 150 m at 1.2 m/min.
Manufactured.
なお、このとき使用した本発明に係る鋳型は、鋳片表層
部の温度が“Cと成分元素の添加量よりCp式を用いて
求めたCp値”から算出したTrに至ったことを検温セ
ンサーが感知すると、コンピュータにより制御されてい
る冷却媒体吹き込み第 4 表
(注)鋳込み方向位置は、モールド上端面からの距離。In addition, the mold according to the present invention used at this time uses a temperature sensor to detect when the temperature of the surface layer of the slab has reached Tr calculated from "Cp value calculated using the Cp formula from the added amount of C and component elements". Table 4 (Note) The position in the casting direction is the distance from the upper end of the mold.
ノズル孔からの冷却媒体噴出量がTTを感知した検温セ
ンサー直上以降のノズル孔についてのみ0.2A/mi
nからQ、4f/minに増加するように設定されたも
のであり、これによって温度がTrである鋳片表層部の
冷却速度を10“C/sec以上とするものであった。The amount of coolant ejected from the nozzle hole is 0.2A/mi only for the nozzle hole directly above the temperature sensor that senses TT.
The cooling rate was set to increase from n to Q, 4 f/min, thereby making the cooling rate of the surface layer of the slab whose temperature was Tr to 10"C/sec or more.
このようにして得られた鋳片の表面疵を目視評価したが
、その結果を第12図に示す。なお、第12図において
「割れ指数」とは、鋳片1d当たりに発生する表面割れ
の総数である。The surface defects of the slab thus obtained were visually evaluated, and the results are shown in FIG. In FIG. 12, the "crack index" is the total number of surface cracks occurring per 1 d of slab.
第12図からも明らかなように、本発明の鋳型を使用す
ると、表面割れ指向の強い鋼であっても表面疵が殆ど発
生しなくなり、無手入れ化が可能となることが分かる。As is clear from FIG. 12, when the mold of the present invention is used, almost no surface flaws occur even in steel that is prone to surface cracking, and maintenance can be avoided.
実施例 2
第3表に示されるところの、連続鋳造鋳片には表面疵が
発生しにくいもののその後の熱間圧延時に割れを生じ易
い成分組成であるB鋼を溶解し、第2図で示されるよう
な水冷銅鋳型(下部内壁面2が上部内壁面よりも20+
+n後退しているほかは第1回と同様のもの)を使用し
て実施例1におけると同様条件で断面寸法が25011
X1200mmのスラブを製造した。Example 2 Steel B, which is shown in Table 3 and has a composition that does not easily cause surface defects in continuously cast slabs but is likely to crack during subsequent hot rolling, was melted and water-cooled copper mold (lower inner wall surface 2 is 20+
The cross-sectional dimension was 25011 under the same conditions as in Example 1 using
A slab with a diameter of 1200 mm was manufactured.
表面温度=950℃でスラブ矯正点を通過したスラブに
ついて表面性状の観察を行ったところ、本発明に係る鋳
型を使用した場合及び従来の鋳型を使用した場合のいず
れのスラブにも表面疵は認められなかったが、前記スラ
ブ矯正点を通過したスラブを切断し、約900℃の温度
にてそのまま125fl厚にまで5バスでの圧延を実施
したところ、本発明に係る鋳型を用いたものには表面疵
の発生が全く認められなかったのに対して、従来の鋳型
によるものは割れ疵が多発することが観察された。When the surface properties of the slabs that had passed through the slab straightening point at a surface temperature of 950°C were observed, no surface flaws were observed on both slabs when the mold according to the present invention was used and when the conventional mold was used. However, when the slab that had passed through the slab straightening point was cut and rolled in 5 baths at a temperature of about 900°C to a thickness of 125 fl, it was found that using the mold according to the present invention No surface flaws were observed at all, whereas many cracks were observed in the molds made using conventional molds.
く総括的な効果〉
以上説明したように、この発明によれば、連続鋳造途中
や、これに続く熱間圧延中に割れ疵を発生し易い鋼種を
用いても、それらのトラブルを生じることなく所望製品
の製造を実施することが可能となるなど、産業上極めて
有用な効果がもたらされるのである。Overall Effects> As explained above, according to the present invention, even if a steel type that is prone to cracking is used during continuous casting or during subsequent hot rolling, these problems will not occur. This brings about extremely useful effects industrially, such as making it possible to manufacture desired products.
第1図及び第2図は、いずれも本発明の鋳型を使用した
連続鋳造の状況を示す模式図であって、第1図と第2図
はそれぞれ別形式の鋳型を使用したもののれいを示して
おり、
第3図は、C含有量と鋳片表面疵発生頻度との関係を示
すグラフ、
第4図は、Fe−C系鋼のC含有量とオーステナイト粒
径との関係を示すグラフ、
第5図は、Fe−C系平衡状態図、
第6図は、鋼のCp値とオーステナイト粒径との関係を
示すグラフ、
第7図はζ鋼のCp値とオーステナイト単相化温度(T
T)との関係を示すグラフ、
第8図は、泪の冷却速度とオーステナイト単相化温度(
Tr)との関係を示すグラフ、第9図は、冷却途中の各
種C含有量の炭素鋼を種々の温度にて水焼入れして組織
を固定した際の、水焼入れ温度とオーステナイト粒系と
の関係を示すグラフ、
第10図は、オーステナイト単相化温度(Ty)の前後
における組織変化を比較した顕微鏡写真図であり、第1
0図(a)は1470℃(T r + 5℃)から水焼
入れした状態を、そして第10図(b)は1460’C
(TT−5℃)から水焼入れした状態をそれぞれ示すも
の、
第11図は、柵のオーステナイト単相化温度以降の冷却
速度とオーステナイト粒系との関係を示すグラフ、
第12図は、通常鋳型と本発明に係る鋳型を用いたとき
の鋳片の割れ指数を比較したグラフである。
図面において、
■・・・鋳型、 2・・・下部内壁面、3・
・・検温センサー、
4・・・冷却媒体吹き込み用ノズル孔、5・・・上部内
壁面、
6・・・冷却媒体吸引用導通孔、
7・・・?容鋼、 8・・・メニスカス、
9・・・凝固シェル、 10・・・冷却水通路、−
11・・・冷却水スプレーノズル。Fig. 1 and Fig. 2 are both schematic diagrams showing the situation of continuous casting using the mold of the present invention, and Fig. 1 and Fig. 2 respectively show the progress of continuous casting using molds of different types. Fig. 3 is a graph showing the relationship between C content and the frequency of occurrence of defects on the slab surface; Fig. 4 is a graph showing the relationship between C content and austenite grain size of Fe-C steel; Figure 5 is a Fe-C system equilibrium phase diagram, Figure 6 is a graph showing the relationship between Cp value of steel and austenite grain size, and Figure 7 is a graph showing the relationship between Cp value of zeta steel and austenite single phase temperature (T
Figure 8 is a graph showing the relationship between the cooling rate of tears and the austenite single phase temperature (T).
Tr) is a graph showing the relationship between water quenching temperature and austenite grain system when carbon steels with various C contents are water quenched at various temperatures during cooling to fix the structure. The graph showing the relationship, Figure 10, is a micrograph comparing the structural changes before and after the austenite single phase temperature (Ty).
Figure 0 (a) shows the state after water quenching from 1470°C (T r + 5°C), and Figure 10 (b) shows the state after water quenching from 1460'C.
Figure 11 is a graph showing the relationship between the cooling rate and austenite grain system after the austenite single-phase temperature of the fence, and Figure 12 is a graph showing the relationship between the austenite grain system and the austenite grain system. It is a graph comparing the cracking index of the slab when using the mold according to the present invention. In the drawing, ■... Mold, 2... Lower inner wall surface, 3...
... Temperature sensor, 4... Nozzle hole for cooling medium injection, 5... Upper inner wall surface, 6... Conduction hole for cooling medium suction, 7...? Yonggang, 8...meniscus,
9... Solidified shell, 10... Cooling water passage, -
11... Cooling water spray nozzle.
Claims (2)
面に検温センサーと冷却媒体吹き込み用ノズル孔とが配
設され、かつ該鋳型下部内壁面の上方に冷却媒体吸引用
導通孔が設けられてなることを特徴とする、鋼の連続鋳
造用鋳型。(1) In a mold with both ends open for continuous casting, a temperature sensor and a nozzle hole for blowing a coolant are arranged on the inner wall surface of the lower part of the mold, and a conduction hole for sucking the coolant is provided above the inner wall surface of the lower part of the mold. A mold for continuous steel casting, which is characterized by:
壁面が後退させられるとともに、該後退内壁面に検温セ
ンサーと冷却媒体吹き込み用ノズル孔とが配設され、か
つ前記後退内壁面の上方に冷却媒体吸引用導通孔が設け
られてなることを特徴とする、鋼の連続鋳造用鋳型。(2) In a mold with both ends open for continuous casting, the inner wall surface of the lower part of the mold is retracted, and a temperature sensor and a cooling medium injection nozzle hole are arranged on the retracted inner wall surface, and above the retracted inner wall surface. A mold for continuous casting of steel, characterized in that it is provided with a through hole for sucking a cooling medium.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP61166894A JP2518618B2 (en) | 1986-07-16 | 1986-07-16 | Mold for continuous casting of steel |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP61166894A JP2518618B2 (en) | 1986-07-16 | 1986-07-16 | Mold for continuous casting of steel |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS6326239A true JPS6326239A (en) | 1988-02-03 |
JP2518618B2 JP2518618B2 (en) | 1996-07-24 |
Family
ID=15839597
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP61166894A Expired - Lifetime JP2518618B2 (en) | 1986-07-16 | 1986-07-16 | Mold for continuous casting of steel |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2518618B2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01202234A (en) * | 1988-02-05 | 1989-08-15 | Katayama Chem Works Co Ltd | Quality improving agent for starchy food |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS544224A (en) * | 1977-06-11 | 1979-01-12 | Nippon Steel Corp | Improving method for toughness of steel material |
JPH0324297A (en) * | 1989-06-22 | 1991-02-01 | Nkk Corp | Composite plating film having superior releasability |
-
1986
- 1986-07-16 JP JP61166894A patent/JP2518618B2/en not_active Expired - Lifetime
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS544224A (en) * | 1977-06-11 | 1979-01-12 | Nippon Steel Corp | Improving method for toughness of steel material |
JPH0324297A (en) * | 1989-06-22 | 1991-02-01 | Nkk Corp | Composite plating film having superior releasability |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH01202234A (en) * | 1988-02-05 | 1989-08-15 | Katayama Chem Works Co Ltd | Quality improving agent for starchy food |
Also Published As
Publication number | Publication date |
---|---|
JP2518618B2 (en) | 1996-07-24 |
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