... synthetic diamond, and it is used to couple the drill bit with the core barrel. Its main function is to ... old one. It also acts as a stabilizer for drill bit. We can produce reaming shells with 6", 10" ... of reaming shell is physically longer than the standard type, it is necessary to use an appropriate inner tube ... AQ, BQ, NQ, HQ, PQ (Front end & Back end Type) T Series: T36, T46, T56, T66, T76, T86 WF ...