CONTINUOUS CASTING METHOD FOR BILLET CAST PIECE

• Main Authors: MURAKATA YUJI, NISHIOKA AKIRA, IIDA SHINJI
• Format: Patent
• Language: English; Japanese
• Published: 07.05.2020
• Subjects: CASTING; CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES; PERFORMING OPERATIONS; POWDER METALLURGY; TRANSPORTING

To suppress bending which occurs at a tip while stably and reliably suppressing occurrence of center porosity, particularly when continuously casting a billet cast piece having a cross sectional area of 500 cmor less.SOLUTION: A continuous casting method for billet cast piece by which a billet cast piece, of which a surface temperature, when a tip of the billet cast piece passes an inlet of an end solidification cooling zone, is so adjusted as to fall within a prescribed temperature range, is water-cooled in the end solidification cooling zone which is located at a position separated from meniscus of molten steel in a template in a casting direction by a prescribed distance, and solidification is completed in the end solidification cooling zone. According to this method, the tip of the billet cast piece gradually increases a specific amount of cooling water in the end solidification cooling zone from a specific water amount smaller than a predetermined specific water amount in association with billet cast piece progression, and so makes the specific water amount as to be the predetermined specific water amount after having passed from the inlet of the end solidification cooling zone by a prescribed length.SELECTED DRAWING: Figure 2 【課題】特に断面積が５００cm2以下のビレット鋳片を、センターポロシティの発生を安定的かつ確実に抑制しつつ連続鋳造する場合に、先端部に発生する曲がりを抑制する。【解決手段】鋳型内における溶鋼のメニスカスから鋳造方向に所定距離隔てた位置に設置した凝固末期冷却帯で、ビレット鋳片の先端が凝固末期冷却帯の入口を通過する際の表面温度が所定の温度範囲となるように調整されたビレット鋳片を水冷し、当該凝固末期冷却帯で凝固を完了させるビレット鋳片の連続鋳造方法である。凝固末期冷却帯での冷却水の比水量を、ビレット鋳片の先端部は、予め定められた比水量よりも少ない比水量からビレット鋳片の進行に伴って徐々に増加させ、ビレット鋳片の先端部が前記凝固末期冷却帯の入口から所定長さ通過した後に前記予め定められた比水量とする。【選択図】図２