... 3m &1.5m, with multi-heat treat, China Drilling Geological Equipment ltd., is the main professional ... manufacturer of drilling tool in china, and specializing in the design and manufacture ... a wide range of drilling tool including drill rod, wireline core barrel (AQ-PQ) and assemblies ... , overshot, hoisting plug, water swiel, wrench. 1.Drill rod: BQ, NQ , HQ, PQ, NT, HT Casing tube ...