Drilling rod: made by CNC, and multi-heat treat, with premium alloy steel BQ,NQ, HQ, PQ ... : geotechnical exploration, Mining exploration, Oil exploration and hydrapower station grouting project ( wireline core drilling and double-tube core drilling)We produce a wide ... , water swivel, overshot, outer tube & inner tube wrench, foot clamp,etc. BQ NQ HQ PHD HWT drill rod, multi-heat treat, 5ft and 10ft