- The safety system of extremely thick coal seam is built and the extremely thick coal seam with coal bumping tendency in Qianqiu coal mine is extr...
- Analysis on plastic wriggle, reduction of well diameter, bit burying, bit jamming and being difficult for casing etc. under complicated pressure system and high pressure of the extremely thick layer.
- thick and extremely thick ore -body
- steeply inclined and extremely thick coal seam
- steep-inclined and extremely thick coal seam
- My heart beat thick in the course of the interview.