2012 New type DTH drilling rig 1,Driving type:pneumatic and ... Crawler DTH drilling rig 3,CE,ISO9001 4,Warranty 2Ys 2012 New type DTH drilling rig:Zhengzhou Dayu Machinery Co.,Ltd. have ... whole equipment have small vibration and working stable. 3,New type boom of Dayu DTH drilling rigThe scope adjustable sysytem ... of DTH drilling rigZhengzhou Dayu Machinery Co.,Ltd web: 2012 New type DTH drilling rig