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Given the difficulty in drilling the anchor holes in the roadway floor of the coal mine, the characteristics of slag movement in the process of positive and negative circulation drilling are analyzed. It is concluded that the interaction between the three zones of drilling and slag is the fundamental reason restricting the rapid drilling of the anchor cable hole in the floor, and it is proposed that the pump reverse circulation drilling can effectively prevent the formation of the three zonesdoi:10.1155/2021/8817498 fatcat:6ibxjysbx5aylm25bfrfz7ciai