

In mineral exploration, geological surveys and geotechnical engineering, the reverse circulation drilling rig has become the preferred equipment for more and more professional users. It adopts a unique double-wall drill pipe design, uses compressed air to drive the DTH hammer to break rocks, and conveys cuttings to the surface continuously and stably through reverse circulation. Unlike core drilling, the reverse circulation drilling rig collects cuttings samples instead of core samples, with faster sampling speed and pure, pollution-free samples. As professional reverse circulation drilling equipment, the YG series has been widely used in many drilling projects at home and abroad.【WhatsApp/WeChat/Phone】+86 13837122632
Parameters of the YG RC Drilling Machine
| RC500 | |||
| Max drilling depth | 500 m | Drilling diameter | 115-305 mm |
| Air pressure | 1.05-3 Mpa | Air consumption | 16-42 m³/min |
| Drill pipe length | 3 m | Drill pipe diameter | 89/108/127 mm |
| Axial pressure | 7T | Lifting force | 15T |
| Fast lifting speed | 14.5 m/min | Fast feeding speed | 21 m/min |
| Max rotary torque | 5000-800 Nm | Max rotary speed | 0-120/0-150 r/min |
| auxiliary winch lifting force | 20T | Drilling efficiency | 10-25 m/h |
| Driving speed | 2.5 Km/h | Uphill angle | 21° |
| Weight | 11 T | Dimension | 6.8×2.1×2.8 m |
| Working condition | Loose layers and bedrock | Drilling methods | Top drive hydraulic rotation and feed, DTH hammer or mud drilling |
| power | Cummins 154 kW | Optional accessories | Reverse circulation device, mud pump, generator, foam pump |
Working Principle of Reverse Circulation Drilling Rig
The core of the RC drilling machine is the double-wall drill pipe, which consists of an outer pipe and an inner tube. During operation, compressed air flows down through the outer pipe and drives the pneumatic hammer to drive the tungsten carbide drill bit to break rock formations. Pressure difference creates reverse circulation, allowing cuttings to flow back to the surface steadily through the inner tube. The cuttings then pass through a hose to a cyclone separator for splitting, and finally fall into sample bags marked with depth for direct laboratory analysis. Compared with core drilling, this equipment obtains cuttings samples with the advantages of high speed, low cost and pure samples.
Advantages of the YG Reverse Circulation Drilling Rig
YG reverse circulation drilling equipment has many unique advantages in design and manufacturing, each bringing significant efficiency improvement and cost saving to actual construction:
- Strong stability: The mast can extend and contact the ground through compensating cylinders, keeping the machine stable even on uneven sites, effectively reducing hole deviation and improving drilling quality.
- Protection of drill pipe threads: The compensating slide automatically protects drill pipe threads from collision and wear during handling. This can extend drill pipe service life by more than 30% and greatly reduce consumable replacement costs.
- Safe and convenient drill pipe handling: Combined with a lifter and hydraulic wrench, drill pipe connection and disassembly are safe and fast. Work that once required multiple people can now be finished easily by one person, cutting labor intensity by more than half.
- High hole-opening accuracy: The unique drill centering device with a level ensures precise hole starting. The centering device opens and closes freely, and the combined clamp has an adjustable inner diameter to perfectly match different drill tools, avoiding waste holes caused by deviation.
- Adaptation to harsh environments: Equipped with a patented air pre-filter, it filters over 90% of dust from intake air and discharges dust automatically without manual cleaning. In high-dust environments such as mines and deserts, engine life is doubled.
- Protection of DTH hammer: A specially designed oil mist lubricator in the air system effectively lubricates the DTH hammer, reducing friction loss and extending maintenance intervals from 200 hours to over 500 hours.
- Durable slideway: The roller slideway is made of wear-resistant steel, reducing wear by 60% compared with ordinary guide rails, maintaining long-term stability even under frequent reciprocating feeding.


Supporting Equipment of the YG reverse circulation drilling machine
In addition to the main machine, a complete reverse circulation drilling system also requires the following supporting equipment:
- Air compressor unit: Provides high-pressure and high-flow compressed air to drive the DTH hammer
- Cyclone separator: Used for collection and splitting of cuttings samples
- Dust collector: Collects drilling dust for environmentally friendly operation
- Drill tool assembly: Including double-wall drill pipes, DTH hammers, tungsten carbide drill bits, etc.
- Optional accessories: Reverse circulation device, mud pump, generator, foam pump (both RC400 and RC500 can be equipped)
YG provides a complete set of reverse circulation drilling machine solutions, allowing users to flexibly select configurations based on drilling depth and formation conditions.
Application Fields of YG Reverse Circulation Drilling Equipment
With the characteristics of high efficiency, environmental protection and pure samples, the RC drilling machine plays an irreplaceable role in many industries:
- Mineral exploration: Used for grade control and ore body boundary delineation in open-pit and underground mines. Compared with traditional core drilling, the RC drilling machine achieves a drilling speed of 10–25 meters per hour, with no cross-contamination in cuttings samples, providing more accurate ore grade data. It is especially suitable for exploration and production drilling of iron, copper, gold, bauxite and other bulk minerals.
- Geological surveys: In regional geological mapping and deep geological structure detection, it quickly obtains continuous formation cuttings profiles, helping geologists accurately judge lithological boundaries and structural features and greatly speeding up mapping progress.
- Hydrogeology and geothermal wells: In arid areas, it requires no mud media, saving large amounts of water. When drilling geothermal and water wells in hard granite and basalt formations, DTH hammer efficiency is much higher than rotary drilling, shortening single-well construction period by 40%.
- Geotechnical engineering investigation: Provides preliminary geological data for highways, high-speed railways, bridges, tunnels, large dams, high-rise buildings and other projects. The RC drilling machine can penetrate complex formations such as pebble beds and fractured zones to obtain representative soil and rock samples, offering reliable support for foundation design and disaster prevention.
- Environmental geological surveys: In soil pollution surveys and groundwater monitoring well construction, it uses no mud medium, avoiding secondary pollution. Collected cuttings truly reflect pollutant distribution depth and concentration, making it an ideal tool for environmental departments in site assessment.
Whether for large-scale exploration projects or small engineering surveys, the YG reverse circulation drilling rig delivers efficient, eco-friendly and accurate drilling support.


Frequently Asked Questions About Reverse Circulation Drilling Rig
Q1: What are the main types of reverse circulation drilling equipment?
A: It mainly includes: air RC drilling rig (driven by compressed air, suitable for hard rock and arid areas), and through-type DTH hammer RC drilling rig (sample recovery rate over 95%). YG’s best-selling models are mainly air reverse circulation drilling rigs.
Q2: Why does the reverse circulation drilling machine perform better in pebble or hard rock formations?
A: It uses high-frequency impact crushing by DTH hammer to directly break pebbles and hard rock, with much higher efficiency than rotary drilling. Meanwhile, cuttings return quickly through the inner tube of double-wall drill pipe without secondary crushing, avoiding sticking and energy waste.
Q3: What should be checked if cuttings stop discharging suddenly during construction?
A: Check in order: whether air compressor pressure is sufficient, whether the inner tube of double-wall drill pipe is blocked, whether the DTH hammer works normally, and whether the cyclone separator and hoses are leaking. Properly controlling drilling speed in daily operation can effectively reduce this problem.
Q4: How to extend the service life of RC drill pipes?
A: Reasonably control drilling pressure and rotation speed, use hydraulic wrenches to protect threads, keep compressed air clean and lubricated, and inspect wear regularly. The compensating slide and roller slideway equipped on YG drilling rigs also effectively protect drill pipes.
Q5: What to do if hole collapse occurs during drilling with reverse circulation drilling machine?
A: Stop drilling immediately and maintain circulation without lifting the drill rashly. Increase mud density or switch to casing drilling (drilling while installing casing). If the drill string is buried, do not pull forcibly; clear the channel first before handling.



