Choosing a wireline core drilling rig should never be based only on maximum drilling depth.
The selected wireline size also has a major influence on drilling equipment requirements.
BQ, NQ, HQ and PQ systems are widely used in geological and mineral exploration.
BQ provides a relatively smaller core and drill-string diameter.
Its lighter drill string can be useful in projects where smaller core samples are acceptable and deeper drilling capability is required.
NQ is one of the widely used sizes in mineral exploration because it provides a practical balance between core diameter, drill-string weight and drilling capability.
HQ produces a larger core sample, providing more geological material for observation and analysis.
However, the larger drill string also increases equipment requirements.
PQ provides an even larger core diameter and can be useful when maximum sample volume is important.
The larger rods and tooling require suitable torque, feed and lifting capacity.
As rod diameter increases:
Drill-string weight increases
Hole diameter increases
Required torque can increase
Fluid circulation requirements change
Pullback demand increases
Tool handling becomes heavier
Therefore, a rig capable of reaching a particular depth with BQ rods may have a different practical depth capability with HQ or PQ rods.
When evaluating a hydraulic drilling rig, contractors should provide:
Target depth
Required core diameter
BQ/NQ/HQ/PQ system
Hole angle
Formation
Drill rod length
Flushing method
YKDRILL supplies drilling rigs and wireline coring tools for different geological exploration requirements.
Correctly matching the rig and core rod system helps create a safer, more efficient and technically appropriate exploration setup.