A full hydraulic core drilling rig is a highly efficient and revenue-generating piece of core equipment in the exploration industry. It uses an advanced load-sensitive hydraulic system that enables stepless and precise control of feed pressure and rotation speed. This allows high-quality and high-recovery core samples to be obtained in various complex geological formations. Its modular design significantly improves transportation and on-site deployment efficiency. In most cases, one operator can complete the main operations, greatly reducing labor and fuel costs.
In this article, we will explain in detail the working process of a full hydraulic core drilling rig in a clear and easy-to-understand way.
Full Hydraulic Core Drilling Rig Parameter
| Model | YGX-400 | YGX-600 | YGX-800 | YGX-1000 |
| Drilling Depth(M) | 180-400-500 | 200-600-650 | 400-800-1000 | 500-1000-1100 |
| Rated pressure(MPA) | 21 | 21 | 25 | 28 |
| Rated Flow(L/min) | 168 | 192 | 260 | 300 |
| Heat Dissipation Mode | Air cooling+water cooling | |||
| Engine Brand | Yuchai | Yuchai | Yuchai | Cummins |
| Rated power/speed | 78kW/ 2400r/min | 92kW/ 2400r/min | 92kW/ 2400r/min | 154kW/2400r/min |
| Drilling Angle(°) | 0-90 | 45-90 | 45-90 | 45-90 |
| Lifting Force(T) | 12 | 16 | 24 | 30 |
| Feed Force(T) | 6 | 8 | 12 | 15 |
| Hydraulic Mud pump flow | 30-90（L/min） | 30-90（L/min） | 90-180（L/min） | 90-180（L/min） |
| Hydraulic Mud pump power | 4-7(MPA) | 4-7(MPA) | 4-7(MPA) | 4-7(MPA) |
| Dimension | 4000*1900*1800mm | 4000*2000*1800mm | 5500*2100*2000mm | 6000*2200*2400mm |
| Weight | 4.3T | 4.5/5.5T | 6.5T | 7.5T |
I. Overview: Six Key Steps of the Drilling Workflow
A complete drilling operation using a full hydraulic core drilling rig is a systematic engineering process. It consists of six major stages:
- Site preparation
- Casing installation
- Core drilling operation
- Core retrieval
- Core handling and geological logging
- Hole completion and sealing
Each stage has a specific technical purpose, and together they ensure high-quality core samples and safe operations.
II. Step-by-Step Explanation of the Process
Step 1: Preparation – The Foundation of Safe and Efficient Work
Before starting the full hydraulic core drilling rig, thorough preparation is essential to ensure safety and efficiency.
- Site leveling and rig positioning: The working area must be leveled and compacted to provide a stable foundation for the rig. This prevents sinking or tilting during drilling, which could affect borehole accuracy.
- Rig leveling and mast adjustment: The rig is precisely leveled using hydraulic support legs. Although modern crawler systems provide strong stability, fine adjustment is still required to ensure perfect balance. The drilling mast angle is then adjusted according to design requirements. This flexible mast design allows vertical or angled drilling without constructing a traditional tower, improving efficiency.
- Mud circulation system setup: Drilling mud is essential for operation. Mud pits (settling tank and circulation tank) are constructed near the rig. The mud pump system is installed and tested to ensure smooth circulation, which provides:
- Cooling of the drill bit
- Removal of rock cuttings
- Borehole wall stabilization
- System inspection: Before drilling begins, all systems are checked:
- Hydraulic pressure system
- Rotation system
- Hoisting system
- Instrument readings
Step 2: Casing Installation – Stabilizing the Borehole
Before drilling into loose surface layers (soil, sand, gravel), casing must be installed.
- Purpose: Surface layers are unstable and may collapse during drilling. Without casing, problems such as hole collapse, narrowing, or tool sticking may occur.
- Operation: A large-diameter casing is drilled and inserted down to stable bedrock. This casing acts like a protective pipe, isolating unstable formations from the borehole. After casing installation, all core drilling is carried out inside the protected zone.
Step 3: Core Drilling – The Main Operation
This is the most important stage of a hydraulic core drilling rig, where core samples are obtained.
- Drill assembly and start drilling: A double-tube core barrel (outer tube + inner tube) equipped with a diamond bit is connected to the power head. Once mud circulation starts, the hydraulic system drives the drill rotation.
- Advantages of hydraulic control: The full hydraulic system allows
- Stepless speed adjustment
- Stable and smooth drilling
- Low vibration to protect core integrity
- Real-time pressure monitoring for safety
- Drill rod extension: Standard drill rods are added one by one as drilling progresses. Each rod is connected using hydraulic make-and-break systems. The drill string maintains high rigidity, good straightness, and minimal clearance.
- Technical advantage: The thin-wall diamond bit improves penetration speed, while the double-tube system ensures the core is protected from disturbance, resulting in high-quality, intact core samples.
For more details on fully hydraulic core drilling rigs, please click Fully Hydraulic Core Drilling Rig.
Step 4: Core Retrieval
Modern full hydraulic core drilling rigs use wireline coring, which greatly improves efficiency.
- Core full detection: When the inner tube is full of rock core, drilling parameters or sensors indicate completion of a drilling cycle.
- Wireline retrieval process: Instead of pulling out the entire drill string, a wireline overshot tool is lowered through the drill rod. It locks onto the inner tube and lifts it directly to the surface using a winch system.
- Core extraction: At the surface, the inner tube is opened, and the core is removed. A new inner tube is then inserted immediately, allowing continuous drilling without pulling out drill rods. This process improves efficiency by more than 70%.
Step 5: Core Handling and Geological Logging
The extracted core is a valuable geological record and must be carefully processed.
- Core arrangement: Core samples are placed in sequence inside core boxes according to depth order.
- Cleaning and marking: The core is cleaned, measured, and marked with depth and drilling cycle information.
- Geological description: Geologists record detailed information such as:
- Rock type
- Color and structure
- Mineral composition
- Fractures and weathering
- Ore characteristics
These records form the foundation for resource evaluation and geological research.
Step 6: Completion – Hole Sealing and Site Restoration
After reaching the target depth, drilling operations are completed.
- Drill pipe removal: All drill rods, tools, and casing are safely pulled out using the rig’s powerful hydraulic lifting system.
- Borehole sealing: To prevent groundwater contamination and geological hazards, the borehole is filled with cement slurry for permanent sealing.
- Site restoration: All temporary facilities are removed, and the site is leveled and restored to its original condition, ensuring environmentally responsible drilling.
Core drilling rigs and fully hydraulic core drilling rigs work on similar principles, both used for rock exploration and core sampling. So what are the differences between them? Please click here for the differences between core drilling rigs and fully hydraulic core drilling rigs.
III. How Hydraulic Technology Improves the Entire Process
Across all stages, the hydraulic core drilling rig provides major advantages:
- Mobility and setup: Crawler chassis allows easy movement across rough terrain. Mast systems simplify installation.
- Drilling control: Hydraulic systems provide precise speed control, stable pressure regulation, and real-time monitoring
- Efficiency improvement: Wireline coring dramatically reduces non-productive time, making deep drilling economically viable.
- Safety and reliability: Overload protection and stable structure design ensure safe operations even in complex geological conditions.
Hydraulic Core Drilling Rig for Sale-Choose YG Machinery
The working process of a full hydraulic core drilling rig is a highly integrated system combining mechanical engineering, hydraulic control, geology, and modern drilling technology. It is not just a sequence of operations, but a complete scientific method for safely and efficiently obtaining underground geological information with minimal environmental impact. Whether for mineral exploration, engineering investigation, or scientific research, choosing a high-quality hydraulic core drilling rig ensures reliable performance and efficient results. From copper belts in Africa to gold mines in South America, and from nickel deposits in Southeast Asia to oil exploration in Central Asia, this technology is playing a key role worldwide.
If you are looking for a hydraulic core drilling rig for sale, please fill out the form below to contact YG.