... high quality alloy,3m &1.5m,with multi-heat treat,BW NW HW HW China Drilling Geological Equipment ltd., is the ... ( wireline core drilling and double-tube core drilling)We produce a wide range of drilling tool including drill rod, wireline core ... rod: BQ, NQ , HQ, PHD, BT, NT, HT casing tube: BW, NW, HW, HWT2.Core barrel: BQ,NQ,HQ,PQ , head ...