초록 ▼

Disclosed is a method for manufacturing hot rolled steel sheets. The method includes the steps of passing molten steel through a continuous caster (11) having a mold after having been passed through a ladle (91) and a tundish (92) to manufacture a slab; cutting the slab to predetermined lengths usin

Disclosed is a method for manufacturing hot rolled steel sheets. The method includes the steps of passing molten steel through a continuous caster (11) having a mold after having been passed through a ladle (91) and a tundish (92) to manufacture a slab; cutting the slab to predetermined lengths using a cutter (14a) to form a plurality of cut slabs; heating the cut slabs to a predetermined temperature in a first heating furnace (15a) descaling the cut slabs heated in the first heating furnace; rolling the slabs in a reduction unit (13) to a predetermined thickness to form a plurality of flat bars; heating the flat bars to a predetermined temperature in a second heating furnace (15b); coiling the flat bars by a coiling station (16a) while the flat bars are maintained in a heated state; uncoiling the flat bars by an uncoiler (16b); and rolling the flat bars to a predetermined thickness in a finishing mill.

대표청구항 ▼

1. A method for manufacturing hot rolled steel sheets comprising the steps of:passing molten steel through a continuous caster having a mold after having been poured into a ladle and a tundish to manufacture a slab;cutting the slab to predetermined lengths using a cutter to form a plurality of cut s

1. A method for manufacturing hot rolled steel sheets comprising the steps of:passing molten steel through a continuous caster having a mold after having been poured into a ladle and a tundish to manufacture a slab;cutting the slab to predetermined lengths using a cutter to form a plurality of cut slabs;heating the cut slabs to 1000° C. or above to form MnS precipitation on the cut slabs in a first heating furnace;width rolling the cut slabs by using a width roller;descaling the cut slabs heated in the first heating furnace;rolling the slabs in a reduction unit to a predetermined thickness to form a plurality of flat bars;heating the flat bars to a predetermined temperature in a second heating furnace;coiling the flat bars by a coiling station while the flat bars are maintained in a heated state;uncoiling the flat bars by an uncoiler; androlling the flat bars to a predetermined thickness in a finishing mill.2. The method of claim 1 wherein the slabs are heated to a temperature between 1000 and 1200° C. for 5?6 minutes by the first heating furnace.3. The method of claims 1 or 2 wherein the slabs being rolled in the reduction unit are maintained to a temperature between 800 and 1000° C. at an output of the reduction unit.4. The method of claim 3 wherein the slabs casted in the continuous caster undergo liquid core reduction.5. The method of claim 4 wherein a thickness of the slabs casted in the continuous caster is 100 mm, and the slabs undergo liquid core reduction to a thickness of 80 mm.6. The method of claims 1 or 2 wherein the slabs casted in the continuous caster undergo liquid core reduction.7. The method of claim 6 wherein a thickness of the slabs casted in the continuous caster is 100 mm, and the slabs undergo liquid core reduction to a thickness of 80 mm.8. The method of claim 1 wherein the slabs being rolled in the reduction unit are maintained to a temperature between 800 and 1000° C. at an output of the reduction unit.9. The method of claim 8 wherein the slabs casted in the continuous caster undergo liquid core reduction.10. The method of claim 9 wherein a thickness of the slabs casted in the continuous caster is 100 mm, and the slabs undergo liquid core reduction to a thickness of 80 mm.