中文摘要：

通过保国铁矿铁蛋山矿区露天转地下开采实践,顺利地解决了铁蛋山矿区露天转地下开采挂帮矿石回采,强化开采露天底部矿石,形成废石覆盖层,保证选矿生产,地下开采采矿方法的选择等问题,取得了良好的效果,实现了对矿区资源和机械设备利用的最大化,并保证了过渡时期矿石的生产能力,创造了巨大的经济效益,为我国中等规模的露天转地下开采的矿山提供了成功的样板。

英文摘要：

Based on the practice of transferring from open-pit to underground mining in Baoguo iron ore of Tiedanshan ore field,many problems are successfully solved,such as stoping of the hanging wall ore,improving the mining of bottom ores in the open-pit,forming the waste rock cap,ensuring the mineral processing and the selection of mining methods for underground mine in Tiedanshan ore field with good effects.And the maximal utilization of mining resources and mechanical equipment are realized.Also,the ore production capacity is guaranteed in the transition period with a huge economic benefit.This practice provides a successful example for transferring from open-pit to underground mine for moderate scale mines of our country.