Titlebook: Geological Methods in Mineral Exploration and Mining; Roger Marjoribanks Book 2010Latest edition Springer-Verlag Berlin Heidelberg 2010 Fu

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Rotary Percussion and Auger Drilling,percussion or hammer action in conjunction with a chisel bit can be used to penetrate hard material. High-pressure air pumped to the face of the bit down the centre of the rods serves to lubricate the cutting surfaces and to remove the broken rock (cuttings) by blowing it to the surface. The cutting

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