New Bit Designs

RBI-Gearhart

Roller cone bi-center design handles specialty situations

In most bi-center applications around the world, a PDC bi-center bit is utilized. However, in some cases, a PDC cutter will not stand up to all formations. With RBI-Gearhart's roller cone, bi-center situations requiring tough TCI drilling are met. In recent applications, 7-in. and 17-1/2-in. bi-centers were utilized.

In formations where PDC bi-center bits are not up to the challenge, this roller cone bi-center design handles the situation. It is easily assembled in the field.

The uniqueness of the roller cone bi-center is that it can be assembled easily in the field, and if the cutters need to be replaced, it is done simply at the drilling location. Each cutter assembly is machined to a master gauge, creating the easy assembly to the bi-center body with eight set screws. These eight set screws are what create the unique accessibility to replace the cutters in the field. There is no need to be concerned about vibrations, because the 12° taper, along with the eight set screws and wedge system, assures that there is no vibration.