... manufacturer of drilling tool in china, and specializing in the design and manufacture of premium diamond drilling tools for ... rod: BQ, NQ , HQ, PDH, NT, HT, BTW NTW and AW, BW, NW, HW2.Core barrel: BQ,NQ,HQ,PQ ... , head assembly and assembly 3.AQ,BQ,NQ,HQ,PQ, BTW, NTW, T2, T6 etc. Diamond ... core bit, reaming shell & shoe bit (syn. and surface-set, PDC ...