半椭圆回转式井壁底
semiellipse rotation type
井壁竖直附加力
vertical additional force of mine shaft liner
井壁竖向可缩装置
vertical yield device of mine shaft liner
井壁失稳
borehole instability
borehole wall instability
井壁渗漏
water infiltration of shaft-wall
井壁取心仪
rotary sidewall coring tool
井壁破裂
shaft lining rupture
shaft lining rapture
fracturing of shaft lining
breach of well rim
breakage of shaft lining
breaking of well rim
shaft wall fraction
shaft wall fracture
rupture of shaft lining
井壁碰摩
bump and friction in well