BQ/ NQ/ HQ/ PQ Q Series Core Barrel Assembly

The Q-series wireline core drilling rods are internationally recognized standard wireline core drilling tools. Available in BQ, NQ, HQ and PQ specifications, they feature core retrieval via wireline without pulling out the drill string. Suitable for geological exploration ranging from shallow holes down to 3000-meter deep holes, they are widely applied in metal mineral exploration, geological mapping and engineering investigation. 

Optimized structural design delivers superior performance and higher operational safety. Compared with conventional wireline drilling tools, this series boasts broader application scope, fewer wearing parts, simple operation and high core recovery rate.

Core drilling tool: It is a double-tube assembly, without drill bit or reamer.

Core drilling tool (head): Does not include inner and outer tubes, locking guard, locking chamber, locking spring, locking spring seat, centering ring, and seat ring.

Single rod length: 1.5m / 3m (standard)

Drill pipe material: 42MnMoB/ZT850, yield strength ≥ 950MPa

Joint material: 30CrMnSiA, CNC precision thread

Applicable depth: 0–3000m (deep hole reinforced type)

Structural composition (double pipe + retrieval system)

1. Outer pipe assembly: Transmits torque and drilling pressure, protects the borehole wall; includes diamond drill bit, reaming tool, outer pipe, spring locking chamber, seat ring.

2. Inner pipe assembly (core) : Single action + vibration reduction (does not rotate during coring, protects the core); equipped with position reporting, plug reporting; includes retrieval spear head, positioning/suspension mechanism, adjustment mechanism.

3. Retrieval device (Overshot): Quickly grabs the inner pipe with a rope, lifts it to the surface for coring, without the need to pull out the drill pipe.

4. Matching drill pipe: High-strength alloy (42MnMoB/ZT850), numerically controlled precise thread, high torsion / compression strength.

1. Without extracting the core, efficiency doubles: For deep holes, there is no need to pull out the drill pipe; simply retrieve the inner tube to obtain the core, and the efficiency is increased by 3-5 times.

2. High fidelity of core samples: Single-action of the inner tube + vibration reduction, the rate of obtaining core samples from hard rock / soft rock / fractured strata is ≥ 95%, and the geological information is complete.

3. Suitable for all scenarios: AQ-PQ covers 300-3000m, applicable to hard rock / soft rock / fractured strata.

4. High strength and durability: High-quality alloy + overall heat treatment, fewer wear parts, and lower maintenance costs.

5. Real-time status feedback: Notification upon reaching the target / blocking the pipe, reducing accidents and minimizing work time loss.

● Medium and shallow holes (300–600m): Choose BQ, with small diameter and high efficiency, suitable for routine exploration.

● Medium deep holes (600–1500m): Choose NQ, the most versatile option, balancing core quality and efficiency.

● Deep holes (1500–2000m): Choose HQ, with high strength, suitable for hard rock in deep holes.

● Ultra-deep holes (2000–3000m): Choose PQ, with large diameter and high core fidelity, the preferred choice for deep exploration.