Partial RC — Reverse Circulation Adapter
Get Started with RC Drilling at less expense
A partial RC system makes use of a Cuttings Interchange. basically a Reverse Circulation adapter, mounted above the down hole hammer, to route cuttings away from the outside of the drill pipe into the center of the drill pipe. This brings many of the benefits of a RC system. Less air is needed vs. conventional drilling and cuttings are removed faster and easier which facilitates faster drilling. There is less disturbance of the hole/borehole wall. Unlike ‘True’ RC, the cuttings don’t enter through the center of the bit at the very bottom of the hole, but travel around the hammer. The interchange results in better performance than conventional drilling, but cutting removal is not quite as fast or smooth as ‘True’ RC.
Components of a Partial RC System
The Cuttings Interchange reroutes cuttings to the center of the drill pipe and is covered with an Umbrella. The Umbrella prevents air loss around the drilling pipe. A Side Discharge may be used right under your conventional Top Head Drive to route cuttings out the side. Holte recommends using a RC Top Head Drive to route cuttings out the top of the rig for less tooling wear and max Drill Pipe length. The Cuttings Interchange can be used either with a casing driver, a down hole drive shoe, or without any casing. The Cuttings Interchange can be threaded to meet your needs, Hex joint, or serve to adapt between different sub types.