Abstract:

Due to the impact of structure,the stratum in Phoenix mountain is strongly broken,loose and of poor cementation, this cause difficult for into the hole and protect wall.Through research,we find that there are multi-layers siliceous slate and feldspar quartzite of uniform thickness in the area.The layers,which have high silica content, dense hard structure weakly abrasive,are typical hard slip layers.Meanwhile,the formation of instability still exist in multi-carbonaceous slate,water loose,unstable hole wall,these cause difficult for drilling construction.Through multiple construction practice,we finally resolve the drilling problem by using casing wall,reasonably choicing and grinding diamond bit,and using the technical process of solid-free fluid PAB wall.It is worth application for similar mine.

Key words: Hard“slip”layer, Unstable ground, Casing wall, PAB solid free fluid, Phoenix mountain