... machines and made of high quality alloy tube.3m &1.5m, with multi-heat treat, China Drilling Geological Equipment ... station grouting project ( wireline core drilling and double-tube core drilling)We produce a wide range of ... rod: BQ, NQ , HQ, PQ, NT, HT Casing tube: BW, NW, HW, HWT, 2.Core barrel: BQ NQ ... water swivel, overshot (standard,heavy duty), outer tube & inner tube wrench, foot clamp,etc.