Our drill rods are all manufactured by CNC machines and made of high ... the design and manufacture of premium diamond drilling tools for the world engineering: geotechnical exploration, Mining exploration, Oil exploration and hydrapower station grouting project ( wireline ... , overshot, hoisting plug, water swiel, wrench. 1.Drill rod: BQ, NQ , HQ, PQ, NT, HT Casing tube: BW, NW, HW, HWT, 2.Core ...