Patent ID: 7204111

Claim:
A lubricated hot rolling method that uses a lubricating oil which contains at least one of an high-basic alkaline-earth metal phenate, high-basic alkaline-earth metal carboxylate, high-basic alkaline-earth salicylate, or high-basic alkaline-earth metal sulfonate having a basicity of 40 mgKOH/g or higher, wherein the lubricating oil has a viscosity at approximately 40° C. of 800 cSt or less, the method comprising: when a material to be rolled is supplied between at least two rolls, providing the lubricating oil to the rolls using a noncombustible gas, wherein, after the lubricating oil is granulated or atomized into particulates having an average size of approximately at most 1 mm, the noncombustible gas has a flow rate for at least one lubricating nozzle of approximately at least 2000 cm 3 per minute, and a flow velocity of at least 1 m per second in at least 0.01 cm 3 and at most 20 cm 3 per 1 m 2 of a surface area of the roll.