The ultra-short mast drill rig is a version of our machines with “reversed” kinematics, allowing the contractor to drill under 20ft of over headroom to a depth of 60ft, with a 10ft tool in front of the mast. A unique machine that can't be matched in the market.
[pdf] Try to turn the compressor by hand. It should be possible to turn it around. It should turn around smoothly, without any 'hickups' (be sure to completely shut down the air compressor!). Check the isolation of the motor windings.
[pdf] DTH technique was used in well drilling exclusively to dig, accurate, vertical bores, and rotary drilling was used to turn the hole. The Directional DTH system, patented by Atlas Copco, was first used.
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