Granulation of raw materials is the single most important factor in controlling the permeability of the sinter bed and hence the productivity of the sinter line. Treatment of the binding water in a magnetic field reduced its surface tension enabling better binding of the small fraction size and so producing a stronger green ball generating fewer fines on feeding to the sinter bed, improving bed permeability and so enabling line speed to be increased by 11%. This paper reviews the literature and applies the findings to sinter machines at the Bokaro Steel Plant. By S Dhara, M Roy, M K Singh, S Acharya, G M Chowdhury and S K Pan*

* The authors are with the R & D Centre for Iron and Steel (RDCIS), Steel Authority of India Ltd (SAIL) e-mail: subhra@sail-rdcis.com