Cooling apparatus of steel sheet, and manufacturing apparatus and manufacturing method of hot-rolled steel sheet

A cooling apparatus of a steel sheet which is disposed on a lower process side of a final stand in a row of hot finish rolling mills and which comprises a plurality of cooling nozzles arranged in a manner capable of cooling a steel sheet being transported on transporting rolls,

• wherein the cooling nozzles are arranged on an upper surface side and a lower surface side of an area in which the steel sheet passes, so as to spray cooling water over the area;
• the cooling apparatus is provided with at least one of an upper surface guide arranged on the upper surface side and a lower surface guide arranged on the lower surface side;
• the upper surface guide and the lower surface guide respectively comprise:
• inlet holes through which the cooling water sprayed from the cooling nozzles passes;
• and outlet holes through which the cooling water passes to be discharged;
• only the inlet holes or the outlet holes are arranged in a width direction of the steel sheet, forming rows of inlet holes and rows of outlet holes, respectively;
• the row of outlet holes is arranged between the rows of inlet holes in a transporting direction of the steel sheet;
• and
• the row of outlet holes is provided with devices for preventing entering of a steel sheet, which are members to prevent the steel sheet from entering the row of outlet holes.