A cold rolling method includes: a calculation step of calculating a leveling amount of a rolling mill using an out-of-plane deformation amount of a steel sheet measured on an upstream side of the rolling mill; a control step of controlling leveling of the rolling mill on a basis of the leveling amount calculated in the calculation step; and a cold rolling step of applying cold rolling to the steel sheet using the rolling mill controlled by the control step.

A cold rolling method includes: a calculation step of calculating a leveling amount of a rolling mill using an out-of-plane deformation amount of a steel sheet measured on an upstream side of the rolling mill; a control step of controlling leveling of the rolling mill on a basis of the leveling amount calculated in the calculation step; and a cold rolling step of applying cold rolling to the steel sheet using the rolling mill controlled by the control step.

A method manufacturing a steel strip, including the subsequent steps of hot rolling the strip into a hot rolled strip, cold rolling the hot rolled strip and hot dip coating the cold rolled strip with a Zn based coating by leading the strip through a bath including molten zinc and wiping the strip after the coating using a gas knife having a knife slot from which a wiping gas is projected and the steel strip is cold rolled to a final cold rolled thickness of between 0.40 mm and 1.00 mm in a multi-stand cold rolling mill, and the coated steel sheet includes a steel substrate provided with a hot dip metal coating.

A method for producing a grain-oriented electrical steel sheet is disclosed including hot rolling a steel material to obtain a hot-rolled sheet, subjecting the hot-rolled sheet to one cold-rolling step, or two or more cold-rolling steps with intermediate annealing interposed between each cold-rolling step so as to obtain a cold-rolled sheet with a final thickness, and subjecting the cold-rolled sheet to decarburization annealing which also serves as primary recrystallization annealing and then to finishing annealing, in which the decarburization annealing includes a heating step in which the steel sheet is rapidly heated at an average heating rate of 250 C./s or more from 400 C. to a temperature T( C.) of 700 to 900 C. and then held at a heating rate of of the average heating rate or less in any of temperature ranges between 500 C. and 700 C. for a time of 0.10 seconds or more but less than 1.00 seconds.

A method for producing a grain-oriented electrical steel sheet is disclosed including hot rolling a steel material to obtain a hot-rolled sheet, subjecting the hot-rolled sheet to one cold-rolling step, or two or more cold-rolling steps with intermediate annealing interposed between each cold-rolling step so as to obtain a cold-rolled sheet with a final thickness, and subjecting the cold-rolled sheet to decarburization annealing which also serves as primary recrystallization annealing and then to finishing annealing, in which the decarburization annealing includes a heating step in which the steel sheet is rapidly heated at an average heating rate of 250 C./s or more from 400 C. to a temperature T( C.) of 700 to 900 C. and then held at a heating rate of of the average heating rate or less in any of temperature ranges between 500 C. and 700 C. for a time of 0.10 seconds or more but less than 1.00 seconds.

Provided are a cold rolling method, a method of producing a steel sheet, a cold rolling line, and a steel sheet production line that can suppress the occurrence of fracture. The cold rolling method includes: a process of calculating a leveling target value for a cold mill (10) that carries out cold rolling on rolled material, the calculation being based on an index of an asymmetric component of an elongation difference rate distribution of the rolled material after cold rolling at delivery of the cold mill; and a process of executing leveling control of the cold mill. The index of the asymmetric component of the elongation difference rate distribution is calculated based on a correlation between the elongation difference rate distribution and an odd function, where the odd function is obtained by multiplying a first-order power function by an absolute value power function that is greater than zero-order.

Provided are a cold rolling method, a method of producing a steel sheet, a cold rolling line, and a steel sheet production line that can suppress the occurrence of fracture. The cold rolling method includes: a process of calculating a leveling target value for a cold mill (10) that carries out cold rolling on rolled material, the calculation being based on an index of an asymmetric component of an elongation difference rate distribution of the rolled material after cold rolling at delivery of the cold mill; and a process of executing leveling control of the cold mill. The index of the asymmetric component of the elongation difference rate distribution is calculated based on a correlation between the elongation difference rate distribution and an odd function, where the odd function is obtained by multiplying a first-order power function by an absolute value power function that is greater than zero-order.

A manufacturing method of a cold-rolled steel sheet in which the method uses a full-width heating device that heats a steel sheet over an entire area in a width direction of the steel sheet, an edge heating device that heats end portions in the width direction of the steel sheet, and a cold rolling mill that rolls the steel sheet and that is arranged on a downstream side in a rolling direction with respect to the full-width heating device and the edge heating device, the method includes: heating the steel sheet by using the full-width heating device and the edge heating device in such a manner that temperatures of the end portions in the width direction becomes higher than a temperature of a central portion in the width direction of the steel sheet on an entry side of the cold rolling mill.

A manufacturing method of a cold-rolled steel sheet in which the method uses a full-width heating device that heats a steel sheet over an entire area in a width direction of the steel sheet, an edge heating device that heats end portions in the width direction of the steel sheet, and a cold rolling mill that rolls the steel sheet and that is arranged on a downstream side in a rolling direction with respect to the full-width heating device and the edge heating device, the method includes: heating the steel sheet by using the full-width heating device and the edge heating device in such a manner that temperatures of the end portions in the width direction becomes higher than a temperature of a central portion in the width direction of the steel sheet on an entry side of the cold rolling mill.