DTH Ring Bit Drilling Systems for Casing Advancement
Tri-Mach’s DTH ring bit drilling systems are designed for professional foundation and piling contractors who need precise and reliable casing advancement in challenging ground conditions. The systems combine advanced ring bit technology with high-performance DTH pilot bits to drill through overburden and bedrock.
Ring Bit Drilling Method
The Ring Bit Drilling Method utilizes a complete DTH system where the pilot bit, casing ring bit, and casing shoe work in unison to cut a precisely oversized hole around the steel casing, enabling smooth and controlled advancement through varied ground conditions. Operating in conjunction with a Down-The-Hole hammer, the system delivers percussive energy directly to the pilot bit, ensuring efficient penetration through both overburden and hard rock formations. Tri-Mach’s patented Radial Flush-system further enhances performance by minimizing soil disturbance and significantly extending tool life—achieving substantially higher drilling meters per pilot bit compared to conventional drilling systems.
Performance Benefits
- Drilling efficiency: High penetration speed with minimal energy loss, even in mixed overburden and bedrock formations.
- Penetration rate: Optimized impact transfer from the Down-The-Hole hammer ensures fast advance through soil and hard rock layers.
- Alignment accuracy: The pilot bit and casing ring bit maintain precise casing trajectory for secure foundation and piling work.
- TRI-MACH personnel have Contractor experience to solve multiple types of geotechnical and production issues
Specifications
Pile Wall (mm) | Ring Bit OD (mm) | Ring Bit ID (mm) | Pilot Bit OD (mm) | Ring Bit OD, PW (mm) |
---|---|---|---|---|
219 | 230 | 150 | 191 | 274 |
273 | 288 | 181 | 245 | 328 |
324 | 339 | 245 | 295.5 | 379 |
406 | 420 | 315 | 375.5 | 461 |
508 | 523 | 410 | 476.5 | 563 |
610 | 630 | 475 | 573 | 665 |
711 | 728 | 565 | 675 | 766 |
813 | 835 | 672 | 777 | 868 |
914 | 935 | 777 | 877 | 969 |
1016 | 1036 | 880 | 983 | 1071 |
1219 | 1240 | 1080 | 1185 | 1275 |
> Same pilot bit for single pile & pile wall ring bits
> Same pilot bit for solitary, integrated and heavy duty ring bit types
> Custom diameters available up to 1524 mm
DTH RING BIT SYSTEM TYPES
Tri-Mach offers two DTH ring bit system configurations to meet different project requirements: the Integrated Ring Bit System, where the ring bit is welded to the casing via a lock ring for maximum safety and underwater operation; and the Solitary (Loose) Ring Bit System, where the ring bit is connected to the pilot bit via a bayonet lock for cost-efficient drilling in dry or low-risk conditions. Both systems operate as part of a complete DTH casing advancement system, ensuring high precision, durability, and compatibility across all major shank designs.
Integrated Ring Bit System
The Integrated Ring Bit System is engineered for drilling longer steel casings through soil layers and into bedrock — particularly in projects where welded casing extensions are needed or casings are drilled in underwater conditions. In this system, the ring bit is securely attached to the drilled casing with a welded lock ring, preventing the bit from detaching if the pilot bit is lifted out from the casing. This design ensures safe and stable drilling, even in challenging environments such as marine piling or deep foundation work.

Integrated systems are typically used for end-bearing piles, harbor and underwater piling projects, and pipe walls or king piles where high structural accuracy and load-bearing performance are required. The system enables safe interruption of drilling operations — the pilot bit can be removed and reinserted later without losing alignment or risking ring bit displacement.
Key benefits include enhanced drilling safety for long casings, higher production rates, and reliable performance in variable ground conditions. Like all Tri-Mach ring bit systems, the Integrated Ring Bit System uses the same DTH pilot bit as other configurations, ensuring full compatibility and simplified equipment handling across different pile types.
Solitary Ring Bit System
The Solitary Ring Bit System, also known as the Loose Ring Bit System, is designed for drilling shorter steel casings through soil and into bedrock in dry or low-risk ground conditions. The ring bit is not welded to the casing shoe but connected directly to the pilot bit using a bayonet lock. This simple connection allows quick setup and dismantling on site, making it a practical and cost-efficient choice for shorter pile installations.

Solitary systems are widely used in projects where casing welding extensions are not required, such as building foundations, temporary or sacrificed casings, and slope stabilization. The system performs efficiently in light-to-medium overburden and stable soil, ensuring reliable drilling performance without the complexity of welded joints.
Key benefits include straightforward operation, reduced tooling cost, and compatibility with the same DTH pilot bit used across other Tri-Mach ring bit types. This cross-compatibility simplifies tool management and allows flexible use of equipment across different pile configurations, including Single Pile and Pile Wall applications.
Compatibility and Customization
With our design, all ring bit types can be drilled using the same DTH pilot bit – including Single Pile Ring Bits (Solitary and Integrated) and Pile Wall Ring Bits (Solitary and Integrated). Heavy Duty Ring Bits are also drilled with the same pilot bit design.
Together, these components form a complete DTH casing advancement system, ensuring smooth and controlled casing installation across varying ground conditions.
Custom models can be produced for projects with challenging geotechnical conditions, ensuring optimal durability and performance in every ground type.
Why Choose Our DTH Casing Bits and DTH Piling Solutions?
- Superior Quality and Durability: Our DTH drill bits are made from premium materials, ensuring they can withstand the toughest drilling conditions and offer longer service life.
- Advanced Design: Leveraging cutting-edge technology and innovative design, our DTH drill bits provide superior penetration rates, making them ideal for DTH piling and other demanding drilling applications.
- Customized Solutions: We understand that every drilling project has unique requirements. That’s why we offer customized DTH drill bit solutions tailored to your specific needs, ensuring maximum efficiency and performance.
- Expertise and Support: Our seasoned team brings deep industry experience, offering unmatched client support and guidance. Alongside our top-tier DTH drill bits and ring bit systems, we provide essential maintenance services that can extend your tools’ lifespan by up to 20-30%. This not only ensures optimal performance but also maximizes your investment’s value by reducing the need for replacements.
Tri-Mach provides the best tools for the job
Whether you are involved in construction, mining, or any other industry that requires reliable and efficient drilling through hard rock, our DTH drill bits, DTH casing advancement systems, casing drilling systems and casing ring bit systems are designed to deliver. Our commitment to quality, innovation, and customer satisfaction makes us the go-to choice for professionals seeking the best DTH piling and drilling solutions.
Explore our range of DTH drill bits and discover how our cutting-edge drilling solutions can enhance your operational efficiency and project outcomes. You can trust us to provide the tools you need to tackle the toughest drilling challenges with confidence.
FAQ: DTH Casing Ring Bits
Do you have any further questions? Please feel free to contact Matias!

Matias Niemeläinen
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