Cold rolling method, cold rolling equipment, and cold-rolled steel sheet manufacturing method

A cold rolling method for cold-rolling a material to be rolled by a rolling mill including a plurality of stands,

• wherein an N-th stand (N is a natural number equal to or greater than 2) arranged in an N-th position from an upstream side of the material to be rolled in a transfer direction and an (N+1)-th stand arranged in an (N+1)-th position on a downstream side of the N-th stand among the plurality of stands, include a tapered work roll having a taper formed on an end portion of a roll having a uniform diameter, and
• each of the N-th stand and the (N+1)-th stand rolls the material to be rolled with a linear load of 1.7 t/mm or more and a tapered rolling portion width WRδ which is a length, which faces the material to be rolled, of the taper formed on the tapered work roll of each of the N-th stand and the (N+1)-th stand is set as −50 mm to −5 mm.

Cold rolling equipment including a rolling mill having a plurality of stands for cold-rolling a material to be rolled,

• wherein an N-th stand (N is a natural number equal to or greater than 2) arranged in an N-th position from an upstream side of the material to be rolled in a transfer direction among the plurality of stands, includes a tapered work roll having a taper formed on an end portion of a roll having a uniform diameter, and
• a linear load of the N-th stand is set as 0.8 t/mm or more.

Cold rolling equipment including a rolling mill having a plurality of stands for rolling a material to be rolled,

• wherein each of an N-th stand (N is a natural number equal to or greater than 2) arranged in an N-th position from an upstream side of the material to be rolled in a transfer direction and an (N+1)-th stand arranged in an (N+1)-th position on a downstream side of the N-th stand among the plurality of stands, includes a tapered work roll having a taper formed on an end portion of a roll having a uniform diameter, and
• a linear load of each of the N-th stand and the (N+1)-th stand is set as 1.7 t/mm or more, and a tapered rolling portion width WRδ which is a length, which faces the material to be rolled, of the taper formed on the tapered work roll of each of the N-th stand and the (N+1)-th stand is set as −50 mm to −5 mm.