Study on the Performance of Oil-in-Water Emulsions during Cold Rolling of Steel Strip

Abstract

Lean oil-in-water (O/W) emulsions with oil concentrations of 2 to 5% are in general use in industrial rolling mills. The oil formulators and technologists aim to develop more efficient and cost effective O/W emulsions using hybrid emulsifiers and other chemicals. Different researchers have expressed different views on film forming and lubrication characteristics of O/W emulsions. The present authors have carried out a study to assess the film-forming characteristics and tribological performance of three commercially available O/W emulsions of different chemical compositions. Results of the present study indicate that the chemistry of the O/W emulsions plays an important role in their film-forming and tribological characteristics. Rolling emulsions of relatively low stability, high droplet size, and high saponification value are found to provide better lubrication and lower coefficient of friction. There is good correlation between the results of the present experiments and actual observations in industry.