松软煤层 meaning in English

lum

Discussion on theory of compound soft rock roof , soft seam along goaf drivage roadway
松软煤层沿空掘巷理论探讨
The research of supporting technology of the tender coal seam workings in deep seam in nantun colliery
南屯煤矿深部松软煤层巷道支护技术研究
The construction methods and caving protection measures for punching high thick and loosen soft coal seam in luling coal mine no . 2 dark tilt well in huaibei coal mine area are introducded . they include small section enlarged after the heading caving , high negative pressure and multi - raw drilling holes and strenous drawing - off , concentrated cross drill holes , cutting while drawing - off and putting the metal frame away
介绍了淮北矿区芦岭煤矿2主暗斜井采用小断面导硐后刷大、高负压多排钻强抽，密集交叉钻孔边掘边抽及设置金属骨架施工方法和防突措施揭穿高突特厚松软煤层。