DTH Bits

DTH Bits: Premium Tungsten Carbide for Maximum Drilling Performance

MSD (Zhuzhou Jingde Machinery Co., Ltd.) is a China-based rock drilling tools manufacturer with 23+ years of experience. We produce DTH bits in diameters from 90 mm to 864 mm, featuring premium YK05 grade tungsten carbide inserts for mining, quarrying, water well, and construction applications.

How DTH Bits Work

A DTH bit is the cutting tool at the bottom of a DTH drilling system. It is inserted into the DTH hammer chuck via splines and locked by a retaining ring. It receives high-frequency impact energy from the hammer's piston — typically 1,500–3,000 blows per minute.

The tungsten carbide buttons (inserts) on the bit face crush and fracture rock with each impact. Compressed air flowing through the hammer exhausts through ports in the bit face, blowing rock cuttings up the annulus between the drill string and hole wall. Because the DTH bit operates at the bottom of the hole, it receives 100% of the hammer's impact energy regardless of depth.

Tungsten Carbide Insert Technology

YK05 Grade Carbide — MSD DTH bits feature premium YK05 grade tungsten carbide, a cobalt-bonded formulation optimized for an ideal balance of hardness and toughness.

Two-Stage Heat Treatment — Our inserts undergo a proprietary two-stage heat treatment. The first stage hardens the matrix for wear resistance, while the second stage stress-relieves the insert to prevent micro-cracking.

Deep-Seated Cold Pressing — Instead of conventional brazing, MSD utilizes advanced hydraulic cold pressing (interference fit). Each insert is pressed into precision-machined pockets, creating a massive mechanical grip.

Quality Results — This process delivers a sub-1% comprehensive failure rate: gauge button breakage below 0.5% and insert fallout below 0.05%.

Rule of Thumb: Insert quality matters more than bit price. A premium carbide bit that drills 20% more meters costs less per meter than a cheap bit that wears out quickly or loses inserts downhole.

Face Design Selection: Optimizing Energy Distribution

The bit face profile determines how impact energy is distributed and how cuttings are evacuated.

Flat Face — Even energy distribution across the entire face. Most versatile design for mixed or unknown formations. The default choice for general-purpose drilling.

Concave Face — Center-focused energy creates a pilot hole that guides action. Fastest penetration in soft to medium formations and improves flushing efficiency.

Convex Face (Dome) — Concentrates cutting at the gauge while protecting the center. Designed for hard, abrasive rock (granite, quartzite) to extend bit life.

Drop Center — A hybrid design combining aggressive center cutting with gauge protection. Popular for production drilling in variable formations.

Rule of Thumb: Soft rock (f<8) → Concave for speed. Medium rock (f=8–14) → Flat for versatility. Hard rock (f>14) → Convex for gauge protection.

Button Configuration: Spherical, Ballistic, and Conical

Spherical (Domed) Buttons — Round, blunt profile for maximum wear resistance. Preferred for extremely hard rock (f>14). They penetrate slower but last longer in abrasive conditions.

Ballistic (Parabolic) Buttons — Sharp, pointed profile for aggressive penetration. Fastest rate in soft to medium formations, but less durable in abrasive rock.

Conical Buttons — Tapered point profile that balances penetration and durability. A versatile middle ground for medium to hard formations.

Gauge Buttons — Located around the perimeter to maintain hole diameter. MSD gauge buttons are angled to create a reaming action that keeps the hole at full diameter.

Proven Field Performance

Chilean Copper Mine (Convex Face Performance): A mining contractor tested MSD 165 mm convex bits in hard granodiorite (f=16–18). MSD bits achieved 342 meters average life versus 315 meters for a premium European brand — an 8.5% improvement at 35% lower procurement cost.

Indonesian Water Well Project (Concave Face Efficiency): A Java drilling contractor deployed MSD 152 mm concave bits in limestone and sandstone. MSD bits matched the 18 m/hour penetration rate of premium brands while reducing bit cost per meter by 40%.

Why Choose MSD DTH Bits

Premium YK05 Carbide — Optimized formulation delivers superior wear resistance and impact toughness.

Cold Pressing Technology — Eliminates insert fallout issues common with conventional brazing methods.

Sub-1% Failure Rate — Rigorous manufacturing controls ensure maximum reliability across thousands of meters.

Full Shank Compatibility — Shank types matching DHD, QL, SD, MISSION, and NUMA series hammers in diameters from 90 mm to 864 mm.

ISO 9001 Certified — Full quality traceability and 100% inspection of critical dimensions and hardness.

Trusted by 500+ Contractors — MSD DTH bits are operating in 40+ countries across mining, water well, and construction projects.

Technical content reviewed by MSD Engineering Team. | About MSD: Zhuzhou Jingde Machinery Co., Ltd. — 23+ years of DTH drilling tools manufacturing expertise | ISO 9001 Certified | Serving 500+ contractors in 40+ countries