Mastering the Production of 40- and 60-mm-Diam. Grinding Balls in Hardness Classes III and IV at the Donetsk Metal-Rolling Plant

Abstract

Information is presented on the development of a new technology for the production of small-diameter grinding balls that have class-III and class-IV hardness ratings and are made from continuous-cast carbon steel semifinished products with a small cross section. Recommendations are given on the chemical composition of the high-carbon steel, which has superior hardenability. The regimes established for the rolling and heat-treatment operations have made it possible to produce class-III and class-IV-hardnessrated 40-mm-diam. grinding balls and class-III-hardness-rated 60-mm-diam. grinding balls since the successful introduction of the ShPS 30-80 ball-rolling mill. The balls meet the requirements of the standards GOST 7524–89 and DSTU 3499–97.