... 1,All Pneumatic DTH drilling rig2,Hydraulic DTH drilling rig3,Integrated DTH drilling rig4,Truck mounted water well DTH drilling rig5,Crawler ... hole 4,Powerful feeding and rotating system of Dayu DTH drilling rigNew type swing mechanism constituted by cycloidal ... PneumaticZhengzhou Dayu Machinery Co.,Ltd. is professional manufacturer of DTH drilling rigZhengzhou Dayu Machinery Co.,Ltd web: 2012 New ...