What is Reverse Circulation (RC) Drilling?

What is Reverse Circulation (RC) Drilling?

Reverse Circulation (RC) Drilling-Concepts and Benefits  

Those who are looking for the best method for grade control can highly consider Reverse Circulation or RC Drilling. Grade control is actually a term that defines ore blocks and grades in the pit. For exploration programs, the quality of the samples is highly imperative for proper mine planning as well as blasting, and the samples should be reliably accurate.

What is Reverse Circulation (RC) Drilling?

This is a proven and tested drilling method that works best in particular mining circumstances. Drillers commonly use this method on large-diameter holes since this is easier and faster to clean holes. The cuttings and fluid flow up the drill pipes and then down the annulus. In terms of the softer formations, this actually causes fewer washouts and promote faster and more accurate samplings because cuttings aren’t contaminated by the sloughing formation off the hole walls. This also come up the drilling pipe ultimately faster providing a precise formation log.

Benefits of Reverse Circulation Drilling   

The RC drilling method has become widespread and popular mainly because of the many great benefits it provides. These benefits include but not limited to the following:


  • Higher Rate of Penetration


One of the most significant advantages of RC drilling is its higher rate of penetration. The penetration rate usually exceeds about 80m per shift, but this still depends on the conditions of the ground. The drilling speed can mean more significant cost savings to slower methods of drilling.


  • Good Even in Bad Ground


Reverse Circulation drilling is insensitive to the ground condition, which might be difficult or slow to penetrate utilizing other methods. The Dual-pipe RC was developed initially as a method to drill complex geological formations like glacial till, permafrost, broken rocks and more where methods of conventional drilling were ineffective and costly.

The RC drill cuttings are then transported into the surface within the centre tube of the dual-pipe. Due to this, sample recovery is commonly good with high recoveries for clays and fines alike.


  • Environmentally Sound

The Reverse Circulation Drilling has various environmental advantages. RC does not mainly require water for rock drillings. This is an excellent advantage on areas with sensitive and minimal water supply. This drilling method has a very minimal environmental impact.


  • Uncontaminated and Reliable Samples


When cuttings travel across the bit to inner tube towards the cyclone, it’s not introduced to other areas of a hole. This keeps it free from cross-contamination. This also creates the possibilities of producing larger quantities of reliable and high-quality samples. Sample cuttings are easier to keep track of and catalogue. Since samples collected have exact depth and location on which they’re found, interested parties and surveyors can locate mineral deposits in a more precise manner.

The RC Drilling is not just a cost-efficient and timely method. This is also a highly beneficial one considering the many great benefits it delivers including the ones mentioned above. Taking all these positive aspects together, Reverse Circulation or RC Drilling is now recognized as one of the excellent choices for grade control and mining exploration.