How to Choose the Right Button Bit for Rock Drilling

Selecting the right button bit for rock drilling is critical to maximizing penetration rate, reducing downtime, and extending tool life. Whether you're drilling in hard granite, abrasive sandstone, or fractured limestone, the button bit you choose directly impacts efficiency and cost. This guide breaks down the key factors to consider when choosing button bits for top hammer drilling, helping you match the carbide button bit to your rock type, drill rig, and project goals.

Understand Rock Hardness and Abrasiveness

Why Rock Type Matters in Button Bit Selection

Rock formation is the first and most important factor when choosing a button bit for rock drilling. Different rock drill bit types perform best in specific geological conditions.

Pro Tip: Use a hardness test (e.g., Schmidt hammer) on-site to confirm UCS before selecting your carbide button drill bit.

Matching Button Shape to Rock Conditions

• Spherical Button Bits: Best for hard, non-abrasive rock — distributes impact evenly, resists fracture.

• Ballistic Button Bits: Ideal for medium-hard, highly abrasive rock — penetrates faster, wears quicker.

• Drop Center Button Bits: Excellent for soft to medium rock — improves flushing and hole straightness.

• Retrac Button Bits: Perfect for unstable, loose, or fractured rock — retractable skirt prevents jamming.
  

Read more HERE ! What Are the Different Types of Button Rock Drill Bits?

Consider Drilling Depth and Hole Diameter

Bit Diameter vs. Drill Rig Capacity

The hole diameter must match your top hammer drill and project requirements. Common sizes:

Litian Heavy Industry offers custom button bits in 38–127 mm, ensuring perfect fit for Furukawa, Sandvik, and Atlas Copco rigs.

Depth Affects Button Layout and Gauge Protection

• Shallow holes (<5m): Standard or drop center button drill bit — focus on speed.

• Deep holes (>10m): Retrac bit or reinforced gauge buttons — prevents bit loss and deviation.

Evaluate Button Grade and Carbide Quality

Carbide Grade Determines Wear Life

Not all carbide button bits are equal. Premium grades resist wear and thermal cracking:

Button Size and Number

• Larger buttons (Ø12–16 mm): Higher impact, better in hard rock.

• More buttons (7–9): Better flushing, ideal for soft rock.

• Fewer buttons (5–6): Faster penetration in medium rock.

Optimize Flushing and Bit Design Features

Flushing Holes and Bit Face Design

Efficient rock chip removal prevents regrinding and overheating.

When to Choose Retrac vs. Standard Button Bits

Comparison Table: Button Bit Types at a Glance

Final Tips: How to Choose the Right Button Bit

1. Test in the field — run a 10-hole trial with 2–3 bit types.

2. Monitor wear patterns — uneven wear = wrong bit or pressure.

3. Partner with reliable suppliers — Litian offers custom button drill dome bits and wholesale jack button bits with full traceability.

4. Match bit to rig — check thread type (R25, R32, T38, T45).