R25 64mm Flat Face Button Bit Dome Tungsten Carbide 12 Buttons Hard Rock

R25 64mm Flat Face Button Bit for Rock Drilling

The R25 64mm flat face dome button bit is a top hammer rock drilling tool designed for heavy-duty underground tunnelling, drifting and small-hole bench drilling in medium to extremely hard rock formations. Built with a flat face profile and a heavy-duty 12-button arrangement, this 64mm (2.5 inch) bit delivers high drilling stability, clean hole alignment and excellent wear resistance under high-impact percussion.

Product Overview

Equipped entirely with 10mm tungsten carbide buttons (8 gauge buttons + 4 front buttons), the R25 64mm bit provides massive total surface contact to resist severe gauge wear and maintain a full 64mm hole. The dome (spherical) button geometry offers high impact toughness and fracture resistance, while the forged high-strength alloy steel body with advanced heat treatment ensures long thread fatigue life.

Main Applications

• Underground Tunnelling & Drifting: Heavy-duty drilling for mine development and tunnelling projects in hard rock.
• Bench Drilling: Small-hole benching and production drilling in open-pit or underground mining.
• Cut-Hole Opening: The 64mm diameter allows larger charge capacity per hole, ideal for cut holes in tunnel blasting.
• Reaming Operations: Large-diameter reaming with R25 drill rods in hard to very hard rock formations.

Key Features & Advantages

• Flat Face Geometry: Ensures high drilling stability and exceptional hole straightness in hard, broken or abrasive rock.
• Heavy-Duty 12-Button Layout: Eight 10mm gauge buttons slow outer diameter wear and prevent hole tapering, while four 10mm center buttons crush the rock core quickly.
• Dome / Spherical Carbide Buttons: Provides high impact toughness and fracture resistance compared to ballistic profiles in hard rock.
• High-Strength Steel Body: Premium alloy steel (42CrMo) with advanced heat treatment offers strong thread fatigue resistance and a long service life.
• Even Carbide Wear: Distributes impact loads evenly across all 12 buttons for predictable wear and extended regrind intervals.

Product Specifications

FAQ

Q1: What are the primary applications for an R25 64mm flat face threaded button bit?
A: It is primarily used for heavy underground tunnelling, drifting, bench drilling and cut-hole opening in hard to very hard rock formations. The 64mm (2.5 inch) diameter allows larger charge capacity per hole, making it ideal for cut holes in tunnel blasting or large-diameter reaming operations with R25 drill rods.

Q2: Why choose a flat face design over a drop center or concave face for a 64mm R25 bit?
A: The flat face profile offers versatility and stability across a wide range of hard and abrasive rock types without premature center wear, a sturdier bit head structure that resists cracking under heavy impact energy, and even carbide wear by distributing impact loads across all 12 buttons.

Q3: What is the advantage of the 12-button 10mm layout?
A: Eight 10mm gauge buttons slow outer diameter wear and prevent hole tapering and jamming, four 10mm center buttons ensure quick rock crushing and prevent central rock cone buildup, and the uniform large-diameter spherical buttons handle extreme impact loads without chipping or shearing.

Q4: How does a dome (spherical) button compare to a ballistic button on a 64mm bit?
A: Dome buttons are best for hard, abrasive or fractured rock, offering high fracture toughness and slow, predictable wear flat growth under high impact. Ballistic buttons give faster penetration in soft to medium-hard non-abrasive rock but are prone to shearing in heavy impact conditions. Dome buttons are recommended for a 64mm R25 bit operating under high percussive force.

Q5: How can operators prolong the service life of an R25 64mm thread button bit?
A: Regrind buttons when flat spots reach one-third of the 10mm button diameter, maintain clean air or water flushing pressure to remove cuttings instantly, and apply correct feed force to avoid thread fatigue failure or collar bounce.