Abstract: In order to establish a precise mathematical model of oil film thickness in deformation zone， the lubrication in cold rolling process of SUS430 stainless steel strip was studied in the laboratory. According to the principle of statistics， the mathematical model of critical oil film thickness in deformation zone for thermal scratch was built by using the fitting and regression analytical method， and the criterion for deciding thermal scratch defect was put forward on the basis of the thickness comparison method. Storing and calling data through SQL Server 2005， a forecasting and controlling software of thermal scratch was developed in the Visual C++60 environment by MFC technique for stainless steel in tandem cold rolling， and then it was used in the practical production. Statistical results demonstrated that the hit rate of thermal scratch arrives at 8774%， the occurrence rate of thermal scratch decreases by 8381%， and the rolling speed increases by 93%. The software is of significance to the control of products quality of stainless steel strips， and the analysis and solution to the problem of thermal scratch defects in tandem cold rolling.

Key words: stainless steel, thermal scratch, tandem cold rolling, control, software development