Reaming shell is set with natural or synthetic diamond,and it is used to couple the drill bit with the core barrel. Its main function is to ream the hole to the correct constant specific diameter which ensures adequate clearance for the core barrel and sufficient  clearance for the new bit which replaces an old one. It also acts as a stabilizer for drill bit.

We also can produce long reaming shells .They are suitable to use in all formation conditions ranging from broken and abrasive to consolidated and non-abrasive. As this kind of reaming shell is physically longer than the standard type, it is necessary to use an appropriate inner tube extension in order to compensate for the difference in overall reaming shell length.