초록 ▼

In continuously casting molten metal into cast product by a twin-belt machine, it is desirable to achieve dramatic increases in speed (linear feet per minute) at which cast product exits the machine, particularly in installations where steel cast product is intended to feed a downstream regular roll

In continuously casting molten metal into cast product by a twin-belt machine, it is desirable to achieve dramatic increases in speed (linear feet per minute) at which cast product exits the machine, particularly in installations where steel cast product is intended to feed a downstream regular rolling mill (as distinct from a planetary mill) operating in tandem with the twin-belt caster. Such high-speed casting produces product with a relatively thin shell and molten interior, and the shell tends to bulge outwardly due to metallostatic head pressure of the molten center. A number of cooperative features enable high-speed, twin-belt casting: (1) Each casting belt is slidably supported adjacent to the caster exit pulley for bulge control and enhanced cooling of cast product. (2) Lateral skew steering of each belt provides an effective increase in moving mold length plus a continuity of heat transfer not obtained with prior art belt steering apparatus. (3) The exiting slab is contained and supported downstream from the casting machine to prevent bulging of the shell of the cast product, and (4) spray cooling is incorporated in the exit containment apparatus for secondary cooling of cast product.

대표청구항 ▼

In a method for achieving high-speed casting in a continuous casting installation for steel wherein a twin-belt casting machine having upper and lower casting belts revolving respectively around upper and lower exit pulley rolls is producing steel cast product for feeding into a regular rolling mill

In a method for achieving high-speed casting in a continuous casting installation for steel wherein a twin-belt casting machine having upper and lower casting belts revolving respectively around upper and lower exit pulley rolls is producing steel cast product for feeding into a regular rolling mill having minimum rolling speed requirements, wherein the respective revolving casting belt travels past a final backup roller located upstream from the respective exit pulley roll between the revolving casting belts and wherein the cast steel product is issuing from an exit located between said exit pulley rolls, the method comprising the steps of: causing each casting belt to hug the product being cast in the region between said final back-up roller and the respective exit pulley roll, applying first opposed rolling contact to the cast product within less than twelve inches from said exit for supporting and containing the cast steel product, applying at least second and third opposed rolling contact to the cast product downstream from said first opposed rolling contact spaced on centers less than ten inches between successive rolling contact for further supporting and containing the cast steel product, directly impinging first water spray onto the cast steel product between said exit and said first rolling contact for cooling the cast steel product, directly impinging at least second and third spray onto the cast steel product upstream from the second and third opposed rolling contact, respectively, for further cooling the cast steel product. In a continuous casting installation for steel wherein a twin-belt casting machine having upper and lower casting belts revolving respectively around upper and lower exit pulley rolls is producing steel cast product for feeding into a regular rolling mill having minimum rolling-speed requirements, wherein the respective revolving casting belt travels past a final backup roller located upstream from the respective exit pulley roll, wherein the cast steel product is issuing from between the revolving casting belts at an exit between said exit pulley rolls and wherein said cast steel product includes a solidified shell enclosing a molten steel interior, a system for achieving high-speed casting by said twin-belt casting machine for meeting the minimum rollng-speed requirements of said regular rolling mill comprising: means for causing each casting belt to hug the product being cast in the region between said final backup roller and the respective exit pulley roll, a pair of opposed rollers in rolling contact with said solidified shell downstream from said exit, said pair of opposed rollers being positioned at a bulge-resisting-effective distance from said exit for resisting significant bulging of said solidified shell, spray nozzle means positioned above and below the cast steel product for applying cooling sprays of water to said solidified shell from above and from below in a region between said exit and said pair of opposed rollers, and said spray nozzle means being aimed toward said solidified shell in an aiming direction at an acute angle relative to said solidified shell and said aiming direction being inclined upstream toward said exit for cooling the solidified shell adjacent to said exit.