Symmetric overburden drilling Bit with 3 pieces

Symmetric overburden system is a system comprised of an ingeniously simple concentric method of drilling through overburden with casing. Symmetric can drill straight holes at any angle (including horizontal) and to depths beyond 100 meters. Working together as one efficient drill bit, the components are made up of:

1.A pilot bit with large internal flushing holes and external flushing grooves.
2.Symmetrical ring bit (reamer) with internal bayonet coupling.
3. Casing shoe for driving of casing.