Our casing tubes are all manufactured by CNC machines, and made ... hydrapower station grouting project ( wireline core drilling and double-tube core drilling)We produce a wide range of drilling tool ... 1.Drill rod: BQ, NQ , HQ, PHD, BT, NT, HT casing tube: BW, NW, HW, HWT2.Core barrel: BQ,NQ,HQ,PQ ... duty), water swivel(compact plus and standard), overshot, outer tube & inner tube wrench, foot clamp,etc.