... 2.Approve ICQ inspection& obtain UKAS certification PDC core bit with (include any size and oversize)China Drilling Geological ... HQ PQ T2 T6 etc. Diamond core bit, reaming shell & shoe bit (syn. and surface-set, PDC)4. ... 86, T6S-101, T6S-116, T6S-131, T6S-14612. B Series(ISO3552-1) Metric Core Bits: B36, B46, B56, ... according to customer's special requirement. PDC core bit for AQ BQ NQ NQ3 HQ HQ3 PQ PQ3 ...