DTH hammer

Down-the-Hole hammer drilling technology for deep foundations in hard rock and extremely compact formations.

Overview

DTH (Down-the-Hole) hammer technology is designed for drilling in very hard soils and rock formations where conventional rotary drilling methods may be inefficient or impractical.

This system combines rotary motion with percussive action generated directly at the bottom of the borehole. The hammer, positioned behind the drill bit, delivers high-frequency impacts that fracture rock efficiently while rotation ensures borehole advancement.

DTH drilling is particularly suitable for:

Hard rock formations
Conglomerates and boulders
Very dense soils
Deep foundations requiring penetration into rock strata

The technology ensures high penetration rates, precise alignment and reliable performance in challenging geological conditions, making it ideal for infrastructure, energy and industrial projects.

How it works?

Machine positioning and setup

The drilling rig is positioned and equipped with a DTH hammer system and drill string.

Percussive drilling activation

Compressed air activates the hammer located at the bottom of the hole, generating rapid percussive blows.

Simultaneous rotation and penetration

The drill string rotates while the hammer fractures the rock, allowing efficient borehole advancement.

Cuttings removal

Compressed air flushes rock fragments out of the borehole, ensuring continuous drilling progress.

Completion and reinforcement (if required)

Once the design depth is reached, the hole can be equipped with casing, reinforcement or prepared for concrete casting, depending on project specifications.

Advantages

✓ Highly effective in hard rock and compact formations
✓ High penetration rates compared to conventional rotary drilling in rock
✓ Excellent verticality control
✓ Reliable performance at significant depths
✓ Suitable for deep rock-socketed foundations

Limitations

⚠ Higher vibration levels compared to CFA or displacement systems
⚠ Requires compressed air system and specific setup
⚠ Increased wear of drilling tools in abrasive formations
⚠ Not necessary in soft or cohesive soils where simpler technologies are sufficient
⚠ Higher energy consumption and operational costs due to compressed air requirements