I. What is an RC Reverse Circulation Drilling Rig?

An RC (Reverse Circulation) drilling rig is a high-efficiency drilling rig specifically designed for geological exploration and sampling. Its core technology relies on a double-walled drill pipe and compressed air to achieve reverse circulation for slag removal, emphasizing rapid, continuous, and pollution-free sampling.

II. Core Working Principle (Simplified Explanation)

• Double-walled drill pipe: High-pressure air travels through the outer pipe, rock cuttings travel through the inner pipe.

• Air descends from the outer pipe to the bottom of the borehole, driving the down-the-hole hammer to break the rock.

• Rock cuttings are blown back to the surface by the airflow from the inner pipe and collected as samples by a separator.

• Entire process: external inlet, internal outlet; no mixing with borehole wall soil, resulting in clean samples.

III. Key Advantages

• Extremely high speed: 200–300 meters per day, 3–10 times faster than conventional drilling.

• Pure samples: Rock cuttings rise directly from the bottom of the borehole, with almost no borehole wall contamination, ensuring strong representativeness.

• Continuous sampling: No need to stop drilling; sampling can be done simultaneously, resulting in high efficiency and low cost.

• Environmentally friendly: Less or no drilling mud is used, suitable for water-scarce and environmentally sensitive areas.

IV. Main Applications

• Mineral exploration (gold, non-ferrous metals, iron ore, etc.)

• Geotechnical engineering investigation, hydrogeological survey

• Open-pit mine boundary delineation and rapid grade assessment

• Drilling in loose/fractured formations (sand, gravel, fractured zones)

V. Limitations

• Only rock cuttings can be obtained; complete core samples cannot be retrieved, and stratigraphic details cannot be examined.

• Hard rock, deep boreholes, and water-bearing complex formations require the use of other techniques.

Technical Parameters 

Drilling Capacity

• Drilling depth (m): 350

• Drilling diameter (mm): 105–400

• Drill pipe diameter (mm): 76 / 89 / 102

• Drill pipe length (m): 1.5 / 2 / 3

Power Head Parameters

• Rotation torque (N·m): 8000–12000

• Rotation speed (rpm): 40–160

• Feed stroke (m): 3.4

• Lifting force (kN): 300

• Thrust force (kN): 150

• Fast lifting speed (m/min): 25

• Fast feeding speed (m/min): 45

Engine Parameters

• Engine brand: Cummins

• Rated power / speed (kW/rpm): 132 / 2200

Tool Winch

• Lifting force (kN): 25

Matching Air Compressor

• Working air pressure (MPa): 1.7–3.5

• Air consumption (m³/min): 17–42

Equipped with DTH Hammer (Reverse Circulation)

• Medium & high air pressure series

Crawler Parameters

• Travel speed (km/h): 2–3

• Gradeability (°): 25

Overall Dimensions

• Transport dimension (mm): 6000 × 2100 × 2500

• Working dimension (mm): 4200 × 3000 × 6100

Overall Weight (t): 8