... depth: 1 m -6 MDrilling diameter: 300mm-1200mmStandard driller diameter : 300mm-500mmLifting form: hydraulic hoistDrilling time : ... alloy driller Application of geological layers: layer of loess, clay, gravel, sandy containing weathered stone, frozen soil layer. rock, ... sand, building the backfill garbage, the garbage layer.. Concrete pole hole driller