... main professional manufacturer of drilling tool in china, and specializing in the design and manufacture of premium diamond drilling tools for the ... range of drilling tool including drill rod, wireline core barrel (AQ-PQ) and assemblies, synthetic diamond core bits, natural diamond surface-set ... and assemblies3. AQ,BQ,NQ,HQ,PQ, T2, T6 etc. Diamond core bit, reaming shell & shoe bit (syn. and surface- ...