Studies on ball wear in the grinding of Kudremukh hematite-magnetite ore

This paper deals with the evaluation of the mechanical and metallurgical properties of different ball materials such as cast hyper steel, high chrome cast iron and EN-31 (forged) steel procured indigenously, with respect to their relative wear resistance during the grinding of Kudremukh iron ore. Marked ball grinding tests were carried out under different experimental conditions in order to establish the possible wear mechanisms using the above three types of balls. With respect to the overall wear resistance, the different ball materials could be arranged in the following order: High chrome cast iron » EN-31 > Cast hyper steel. The role of oxygen in the mill atmosphere in contributing towards the corrosive wear of balls is analysed. Possible ball wear mechanisms are outlined. The effect of addition of an inhibitor such as sodium nitrite to the grinding mill in reducing ball wear was also studied