Our casing tubes are all manufactured by CNC machines, and ... diamond surface-set core bit, PDC bits (core or noncoring), casing shoes, reaming shells, overshot, hoisting plug, water swiel, wrench. ... .Drill rod: BQ, NQ , HQ, PHD, BT, NT, HT casing tube: BW, NW, HW, HWT2.Core barrel: BQ,NQ,HQ ... heavy duty), water swivel(compact plus and standard), overshot, outer tube & inner tube wrench, foot clamp,etc.