JK930 Truck Mounted DTH Drilling Rig, Hard Rock and Large Diameter Work This is the same JK930 chassis set up for buyers who spend their days in rock: quarry benches, mine access roads, foundation piling in limestone, geothermal boreholes through granite. Bigger hammer, higher air pressure, wider hole range, and a dust package fitted as standard when the site is near people. If your ground is soil and clay most of the way down, order the water well configuration instead. If
