US 12,221,664 B2
Apparatus for manufacturing thin steel sheet and method for manufacturing thin steel sheet
Takuya Takayama, Tokyo (JP); Hiroshi Harada, Tokyo (JP); Kenji Yamada, Tokyo (JP); and Masashi Sakamoto, Tokyo (JP)
Assigned to NIPPON STEEL CORPORATION, Tokyo (JP)
Appl. No. 17/292,984
Filed by NIPPON STEEL CORPORATION, Tokyo (JP)
PCT Filed Nov. 8, 2019, PCT No. PCT/JP2019/043817
§ 371(c)(1), (2) Date May 11, 2021,
PCT Pub. No. WO2020/100729, PCT Pub. Date May 22, 2020.
Claims priority of application No. 2018-213447 (JP), filed on Nov. 14, 2018.
Prior Publication US 2022/0002829 A1, Jan. 6, 2022
Int. Cl. C21D 9/46 (2006.01); B21B 1/46 (2006.01); B22D 11/128 (2006.01); C21D 6/00 (2006.01); C21D 8/02 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/14 (2006.01)
CPC C21D 9/46 (2013.01) [B21B 1/463 (2013.01); B22D 11/1287 (2013.01); C21D 6/005 (2013.01); C21D 6/008 (2013.01); C21D 8/0205 (2013.01); C21D 8/0226 (2013.01); C22C 38/001 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/14 (2013.01)] 12 Claims
OG exemplary drawing
 
1. A method for manufacturing a thin steel sheet using an apparatus for manufacturing a thin steel sheet, the method comprising:
providing an apparatus for manufacturing a thin steel sheet, with which continuous casting, passing-through a holding furnace, and finish rolling are able to be continuously performed without cutting a slab, the apparatus comprising the followings which are arranged in order:
a continuous casting machine for a thin slab having a slab thickness of 70 mm to 120 mm at a lower end of a mold;
the holding furnace that is configured to maintain a temperature of a cast slab and/or heats the cast slab; and
a rolling stand by which finish rolling is performed,
wherein the apparatus has a reduction roll on a downstream side of a solidification completion position of the slab in the continuous casting machine, and
the slab is able to be reduced by the reduction roll;
setting a casting speed of the thin slab at the lower end of the mold to 4 to 7 m/min; and
reducing the slab at a rolling reduction of 30% or more by the reduction roll after solidification is completed and when a center temperature of the slab is 1300° C. or higher.