... large rotary range. 2,piling work and drilling sampling. Small diameter piling drill,Multiple usage ... well as small diameter piling works. Features: 1, Decent gearing speed with large rotary range. 2, Low speed drilling ... tooling. 4, Hydraulic feeding, easy operation, high drilling efficiency, less human efforts. 5, Compressed structure, ... clamping ability. Technical data: water well drilling rig