DTH Hammer

DTH Hammer Drilling Diameter Range

The ideal hole diameter range for DTH hammer drilling is typically between 90 mm (3.5 inches) and 254 mm (10 inches). This range ensures effective drilling efficiency and efficient rock-cutting removal.

· Small Diameter

These holes are typically drilled using top hammer drill jumbos, which apply percussive force at the drill string’s top. Top hammer drill jumbos are suited for medium to hard rock formations.

· Large Diameter

Larger boreholes, particularly those exceeding 10 inches, are usually drilled with rotary rigs, which rely on rotational force and cutting action. 

For example, a standard 102 mm (4-inch) DTH hammer can drill a minimum hole diameter of 102 mm (4 inches), while its maximum recommended bore diameter typically falls between 127 mm and 130 mm (5 inches).

Understanding Operational Requirements

To choose the best DTH hammer, consider:

· Rock Type

Select a DTH hammer based on the hardness, strength, and abrasiveness of the rock. Harder rock formations require higher impact energy and more wear-resistant hammers.

· Hole Size

The hammer size should match the required borehole diameter. There should be adequate annular space between the hammer and borehole walls for efficient cutting removal.

· Equipment Compatibility

Ensure the hammer is compatible with your existing drilling rig. It includes connection type, air pressure requirements, and rotational speed.

Considering the Work Environment

· Site Conditions

Consider air pressure supply, borehole depth, and whether the operation requires wet or dry drilling. These factors influence hammer selection and performance.

Evaluating Hammer Performance

· Impact Energy

Higher impact energy improves drilling efficiency and expands the hammer’s adaptability to different formations.

· Frequency & Rotation Speed

Proper impact frequency and rotation speed improve penetration rates and minimize equipment wear.

· Durability

Choose hammers made from high-strength materials with wear-resistant designs to extend service life and reduce replacement costs.

Seeking Expert Advice

· Consulting Manufacturers or Industry Experts

Reach out for technical support and tailored recommendations.

· Reviewing User Feedback

Learn from industry professionals’ experiences to make informed decisions about performance and applicability.