The new central breeze-well in the topsoil layer of xiaonan coal construction technique working in the sink-well

This text introduces to dig in new central breeze-well in the topsoil layer of XiaoNan coal,pass adoption shut off sand dive pump at worked drain、shut off sand with adopt the peak of the grasp rock machine grasp sneak in water digging out sand etc. synthesizes construction technique in the sink-well,Solving the hard Problem of working in the float sand layer,obtaining struction technique result working in the topsoil layer。