... main professional manufacturer for drilling tools Core barrel: BQ,NQ,HQ,PQ , BQU, NQU backend assembly , China ... bits (core or noncoring), casing shoes, reaming shells, overshot, hoisting plug, water swiel, wrench. These are all ... of outstanding quality and satisfied service.1.Drill rod: BQ, NQ, HQ , PQ , NT, HT, BW, NW, HW ... BW, NW, HW, HWT2.Core barrel: BQ NQ NQ2 NQ3 HQ HQ3 PQ PQ3 head assembly and ...