... , its conductivity and oversized mesh might cause a dangerous environment for miners to work in. Fire-retardent HockGrid® is flexible, light ... -1000kN/m Tensile strength ( warp/weft )kN/m: 30/30,40/40,50/50,60/60,80/80,100/80,120/120 ... Grid,Polyester Geogrid Manufacturers. Polyester Mine Grid 1000-1000kN/m for Longwall Recovery Systems