Administering quality check rolling after the production mannered null annealing of the cold rolling steel sheet which

摘要

PROBLEM TO BE SOLVED: To provide a production method of cold rolled steel plate which improves a degreasing character and chemical conversion treatability without changing a coated amount of antirust oil. ;SOLUTION: When a skin pass rolling on a cold rolled steel plate with a surface roughness being below 1.5 μm in terms of Ra is performed after annealing, an organic material of skin pass rolling lubricant is deposited on a surface of steel plate after being rolled at a rate of 20-80 mg/m² by using a skin pass rolling lubricant which contains 1-15% water-soluble organic material and an antirust oil is coated. The said treatment is also applied to a cold rolled steel plate with a Ni-deposited amount ≤15 mg/m², or to a cold rolled steel plate which is annealed with a surface roughness of a hearth roll in the annealing furnace ≤8 μ in terms of Ra.;COPYRIGHT: (C)2003,JPO