... .polyester mine grid 400-400kN/m for long-wall recovery system roof support,hock mining geogrid,Shandong Hock MiningMine Grid Introduction:Geogrid ... be carried out together with the coal-splitting, pushing and support advance, therefore, the working speed steps up. 5.Fast laying ... ,Biaxial Geogrid. mine grid 400-400kN/m for longwall recovery system,rib and roof support