HOT JOINING METHOD OF SHEET BAR DURING HOT CONTINUOUS FINISH ROLLING

摘要

PURPOSE:To join sheet bars in a short time even under severe hot conditions and to obtain substantial tensile strength by maintaining butt surfaces at a specific temp., pouring a molten steel having the carbon equiv. not lower than the carbon equiv. of one sheet bar between said surfaces and joining the surfaces. CONSTITUTION:The tail end of the preceding sheet bar 1 and the leading end of the succeeding sheet bar 2 are first butted at >=740 deg.C and the molten steel is poured between the butt surfaces thereof. The compsn. of the molten steel to be poured in this stage is so adjusted that the carbon equiv. thereof is made not lower than the carbon equiv. of at least one sheet bar. The strength of the joint part is thus made not smaller than the strength of the sheet bars.