长壁综采放顶煤采煤方法
longwall fully mechanized overhead caving coal mining
大采高综采放顶煤技术
fully mechanized high cutting and top coal caving mining technology
大倾角综采放顶煤
the steep-grade angle and top coal mining
短长壁综采放顶煤
shorter long-wall full-mechanized caving mining
放顶拉底
artifical caving and undercut
放顶煤
top coal caving
caving top coal
top-coal drawing
Top-coal Caving
top-coal caving mining
blasting down coal
caving
Sublevel caving
carry out the head coal
coal caving
caving coal
coal caving mining
longwall face with sublevel caving
放顶煤采煤法
Longwall Mining with Sublevel Caving
放顶煤综采
fully mechanized caving coal
简易放顶煤
Drawing Top-Coal with Hydraulic Props