antimist additives

are chosen as collapse-proofadditive from treating reagent of mud．Aseries of data obtained from the collapse-prooftest in laboratory is applied to the air-foam drilling with 70°inclined hole in the crushedand soft-hard interstratified layers in Nanxiang gold mine.

介绍从泥浆处理剂中选择腐植酸钾等三种试剂作防塌添加剂，经实验室防塌试验获一系列实验数据，并在南乡金矿区７０°斜孔中破碎、软硬互层复杂地层的不稳定孔段进行空气泡沫钻进应用验证，获得较好效果。