Steel Balls for Ball mill can save usage 40-50% than low chrome casting ball(chrome percent: 5%), improve outlet 10% at least than low chrome casting ball. Steel Balls for Ball mill can save usage 20-25% than medium chrome casting ball(chrome percent: 5% ~ 10%), improve outlet 10% than medium chrome casting ball. Steel Balls for Ball mill can save usage 10% than high chrome casting ball(chrome percent: 5% ~ 10%), improve outlet 10% than high chrome casting ball.