导流底孔布置
arrangements of diversion bottom outlets
底孔直径计算
Calculation for Bottom Diameter
分压式孔底局部反循环钻具
differential pressure bore bottom locality reverse circulation tool
基桩孔底
foundation pile bottom-hole
孔底后压浆法
Cement grouting after well completion
孔底间隔装药爆破技术
spacing charging at blast hote bottom explosion technology