In geological exploration and mining projects, choosing the right core drilling rig directly determines operational efficiency, cost control, and data accuracy. BQ, NQ, and HQ are the three mainstream core drilling rig specifications on the market, leaving many exploration professionals confused: what are the differences between them? How should one choose for different projects? This blog post will break down the differences in applicable scenarios for each rig, compare core parameters, and even provide a dedicated selection formula to help you quickly find the most suitable equipment and avoid selection pitfalls!
First, let’s clarify a core understanding: the classification of BQ, NQ, and HQ specifications is primarily based on the core diameter and drilling capacity, which corresponds to different equipment sizes, power requirements, and applicable rock formations. YG, as a brand specializing in core drilling rig R&D, produces BQ, NQ, and HQ core drilling rigs, all of which utilize fully hydraulic drive technology, enabling efficient and accurate core drilling in their respective applicable scenarios. The following analysis will focus on actual operational needs.
Key Parameter Comparison: Understanding the Differences Between BQ/NQ/HQ
| Specifications | Parameter: Core Diameter | Parameter: Maximum Drilling Depth | Applicable Rock Strata | YG’s Corresponding Equipment Advantages |
| BQ Core Drilling Rig | 47-53mm (standard core diameter 47.6mm) | Standard depth: 500-800 meters; YG enhanced version up to 1000 meters | Suitable for soft rock formations (clay, sand), medium-hard rock formations (shale, sandstone), and light exploration in fractured rock formations. | Lightweight design, weighing only 3.8 tons; tracked chassis provides excellent mobility, suitable for small-scale, fine-scale exploration in mountainous areas. |
| NQ Core Drilling Rig | 68-75mm (standard core diameter 75mm) | Standard depth: 200-500 meters; YG fully hydraulic version up to 600 meters | Suitable for medium-hard rock formations (sandstone, limestone) and hard rock formations (granite), suitable for most metallic and non-metallic mineral exploration. | Fully hydraulic intelligent drive, supports stepless speed regulation from 125-1000rpm, core sample integrity rate exceeding 95%, strong adaptability to multiple scenarios. |
| HQ Core Drilling Rig | 89-96mm (standard core diameter 95mm) | Standard drilling depth 100-300 meters, YG heavy-duty version up to 400 meters | Suitable for hard rock formations (granite, basalt) and ultra-hard rock formations (quartzite), ideal for the precise exploration of deep, thick mineral deposits | High-torque top-drive rotary head, maximum lifting force 85kN, paired with wear-resistant drill bits, increases hard rock drilling efficiency by 30% |
In-depth Analysis of Applicable Scenarios: How to Choose a BQ/NQ/HQ Core Drilling Rig for Different Projects?
1. BQ Core Drilling Rig: The First Choice for Shallow and Precise Exploration
The core advantages of the BQ specification are “shallow drilling depth, high precision, and lightweight,” making it suitable for precision exploration projects that do not require high core diameter but need to penetrate deep into shallow strata. For example: shallow geological exploration in the early stages of urban infrastructure construction (such as road and bridge foundation surveys), which requires operation in densely populated urban areas, where the advantages of small size and low noise are obvious; shallow exploration of small non-metallic minerals (such as clay and shale mines), where large-diameter core sampling is not required, and BQ drilling rigs can meet data acquisition needs; and small-scale exploration in mountainous and forested areas with inconvenient transportation, where the lightweight design of the YG BQ core drilling rig facilitates disassembly and transportation, and the tracked chassis can easily handle rugged terrain.
2. NQ Core Drilling Rig: The Mainstay of General-Purpose Exploration
The NQ specification is the most versatile of the three types, a true “all-rounder.” Its core diameter and drilling depth cover most exploration needs, making it the mainstay equipment for mining development and geological surveys. For example, in medium-to-deep exploration of small to medium-sized metal mines (such as copper and iron mines), where both core integrity and operational efficiency are crucial, the NQ rig’s 75mm core diameter meets the requirements for ore layer thickness and grade analysis, and its 200-500 meter drilling depth covers the exploration range of most small to medium-sized mines. In regional geological survey projects requiring multi-point exploration over large areas, the YG NQ core drilling rig‘s rapid deployment design (equipment lifting completed within 30 minutes) significantly improves operational efficiency. Furthermore, for conventional environmental exploration in temperate and subtropical regions, the equipment’s fully hydraulic drive system can handle most terrain and climatic conditions.
3. HQ Core Drilling Rig: A Powerful Tool for Deep Hard Rock Exploration
The core advantages of the HQ specification are its “large diameter, high torque, and high pressure resistance,” specifically designed for deep hard rock exploration. It is suitable for large-scale projects requiring a high core diameter and dealing with hard rock formations. For example, in deep exploration of large metal and precious metal mines (such as gold and silver mines), larger diameter core samples are needed to analyze ore layer distribution and grade variations; the 95mm core diameter of the HQ rig provides richer geological information. In deep infrastructure exploration (such as tunnels and large hydropower station foundations), penetrating ultra-hard rock layers is required to understand deep geological structures; the high torque design of the YG HQ core drilling rig easily handles ultra-hard rock layers such as basalt and quartzite. Furthermore, in shallow deep-sea exploration (such as shallow drilling sampling in the early stages of near-shore oil and gas exploration), the equipment’s high-pressure sealing design adapts to special environmental requirements.
Customized Selection Formula: 3 Steps to Precisely Match Core Drilling Rig Equipment
1. Step One: Determine Core Requirements
First, clarify three key data points:
① Maximum drilling depth required for the project (H);
② Minimum core diameter required (D);
③ Target rock formation hardness (Y, unit: MPa, reference: soft rock Y<30MPa, medium-hard rock 30≤Y≤60MPa, hard rock Y>60MPa).
2. Step Two: Substitute into the Selection Formula for Judgment
① If H≥500m, D≤53mm, Y≤60MPa → Select BQ core drilling rig;
② If 200m≤H≤500m, 53mm<D≤75mm, 30MPa≤Y≤80MPa → Select NQ core drilling rig;
③ If H≤400m, D>75mm, Y≥60MPa → Select HQ core drilling rig.
3. Third Step: Fine-tuning based on the working environment
- If the working environment is in a mountainous or forested area with inconvenient transportation → prioritize lightweight BQ or NQ drilling rigs;
- If it is a harsh environment, such as high temperature or extreme cold → prioritize YG series fully hydraulic drilling rigs (with high and low temperature adaptation optimization);
- If a quick switch of specifications is required → consider the YG NQ core drilling rig (supports BQ/HQ specification compatibility, switchover completed in 10 minutes).
