DTH Drilling - guide

How does it work?

DTH drilling uses a mini air or water driven hammer at the end of the drill string. With DTH hammer you can drive down casings or drill rock holes. A rotation unit is part of the drill rig. Air or water are introduced through the drill casing to the drill hammer to drive the piston that strikes the drill bit into the material.

Why DTH drilling?

DTH drilling has the advantage that the force of the percussion, the active strike on the material, hits directly on the drill bit. Which prevents energy loss through a long drill string. This enables efficient drilling regardless of depth. Which we usually describe saying the hammer doesn’t know how deep it is drilling. Using DTH drilling, you can drill a hole several kilometers down.

Water powered drilling

Water drilling, or Wassara is unlike regular drilling with air, but can be used for sensitive ground conditions. Water – as opposed to air – is incompressable and therefore cannot expand underground while you’re drilling. Water powered drill hammers are therefore used to avoid possible damage to adjacent structures, or creating settlement.

Casing driving

Currently a ring or wing system is most commonly used to drive piles or casing. Asymmetrical systems like Tubex or Odex are still used, but not as commonly as previously.