The primary role of rolling oil in cold rolling is to reduce friction at the rubbing interface of the work roll and metal sheet surface. The rolling performance as well as cost effectiveness of rolled products is influenced by quality of the rolling oil. Lubricants are required to function under increasingly stressful operating conditions, so it is a challenge to evaluate the product under simulated conditions to improve the customer confidence in its performance.
A steel rolling mill customer had requested us to develop a rolling oil to roll stainless steel in a new 3-stand 18-high rolling mill and demonstrate its performance on an experimental set up. The present paper describes the methodology adopted to assess the suitability of a rolling oil for the particular rolling mill. The screening was carried out with a SRV (Schwingungs Reibungs und Verschleisstest, meaning Vibration, friction and Abrasion) tribometer and EHD (Elasto-hydrodynamic) interferometry based film thickness apparatus to assess the frictional and film forming characteristics of the oil under simulated operating conditions. In addition, simulated tests were carried out on a laboratory 2-Hi Experimental rolling mill to find out the specific roll force (rolling force per unit width of the strip being rolled) required to obtain 55–60% cumulative reduction in three passes as desired by the customer for different grades of stainless steel. Based on results obtained in the laboratory mill simulating industrial test conditions, the product was recommended and was accepted by the customer for use in their rolling mill.