Surface qualities of workpiece and behavior of lubricant on tin plate in temper rolling

On the temper rolling especially importance of surface quality such as tin sheet, it is considered as the tribological study to obtain the homogeneous surface quality of the strip. The aims of this study are to examine systematically the effect of tribological factors on the surface qualities in the temper rolling for tin plate and to estimate the surface quality by the analysis of inlet oil film thickness. The temper rolling experiments were carried out, changing the rolling speed, the viscosity of lubricant and the surface roughness of tin plate. The oil film thickness in the inlet zone of contact region is calculated analytically based on Reynolds equation considering the surface roughness of the roll and the tin plate. From these experiment data, the qualitative relationship is found between the calculated oil film thickness and the surface qualities such as the brightness and the roughness. But it is difficult to interpret this relationship quantitatively. However, the surface brightness and the surface roughness are expressed as a function of the oil film thickness. To obtain the high brightness after temper rolling by the roll with mirror finish, it is required that rolling is carried out under the condition of minimum thickness of the inlet oil film as possible.