... professional manufacturer for drilling tools Core barrel: BQ,NQ,HQ,PQ , BQU, NQU backend assembly , China Drilling Geological Equipment ltd., is ... of drilling tool including drill rod, wireline core barrel (AQ-PQ) and assemblies, synthetic diamond core bits, natural diamond surface-set ... quality and satisfied service.1.Drill rod: BQ, NQ, HQ , PQ , NT, HT, BW, NW, HW Casing tube: BW, NW, HW ...