Medium–Low Pressure DTH Bits

Optimized for Balanced Drilling Conditions
Medium–low pressure drilling environments are common in quarrying, water well construction, and civil engineering projects. In these applications, drilling efficiency is not defined solely by peak penetration rate, but by how consistently a drill bit can perform over long operating hours. Medium–Low Pressure DTH Bits are engineered to deliver steady impact energy that breaks rock efficiently while minimizing excessive stress on the bit body and carbide buttons.
Rather than maximizing impact force, these bits are optimized for smooth energy transfer, stable rotation, and controlled wear. This design philosophy helps reduce vibration, limit button breakage, and maintain predictable drilling behavior across different formations.

Bit Body Design and Material Selection
The bit body is manufactured from high-quality alloy steel with controlled chemical composition to ensure uniform mechanical properties. After forging, the body undergoes precision machining and multi-stage heat treatment to achieve a balance between hardness and toughness. This prevents deformation under repetitive impact while maintaining sufficient elasticity to absorb shock.
Compared with high-pressure bits, medium–low pressure DTH bits typically experience lower peak loads but longer cumulative operating hours. For this reason, fatigue resistance and wear uniformity are key design priorities.

Tungsten Carbide Button Configuration
Button selection plays a critical role in medium–low pressure drilling. Semi-ballistic or spherical carbide buttons are commonly used to balance penetration and wear resistance. The button layout is designed to distribute impact evenly, preventing localized stress concentration that can lead to premature button loss.
Gauge buttons are reinforced to maintain hole diameter over time, especially in abrasive formations such as sandstone or mixed limestone layers. Stable gauge protection helps ensure straight holes and reduces the need for reaming or corrective drilling.

Face Geometry and Flushing Efficiency
Efficient cuttings removal remains essential even under lower air pressure. Medium–Low Pressure DTH Bits are designed with optimized face profiles and flushing channels that allow rock chips to be evacuated smoothly without relying on excessive airflow.
Concave and drop-center face designs are frequently used in these applications, as they promote stable tracking and reduce hole deviation. Proper flushing reduces regrinding, lowers heat buildup, and extends both bit and hammer service life.

Medium–Low Pressure DTH Bits are widely used in:

• Quarry production drilling, where consistent hole quality and long bit life are essential for daily operations.
• Water well and borewell drilling, especially in sedimentary and mixed formations where controlled penetration is preferred.
• Construction and foundation drilling, including anchor holes and small to medium diameter piling projects.

In a Southeast Asian limestone quarry, medium–low pressure DTH bits were used with 10–14 bar compressors for 89–127 mm production holes. Field results showed stable penetration rates throughout the drilling cycle, with average bit life exceeding 18–22% compared to conventional low-cost bits. Operators also reported fewer interruptions due to button damage.

Each Medium–Low Pressure DTH Bit follows a standardized manufacturing route that includes forging, CNC machining, controlled heat treatment, and precision button insertion. Button seating tolerances are carefully controlled to ensure reliable retention during long drilling runs.

Final assembly includes visual inspection, dimensional checks, and hardness verification. Selected batches are tested under simulated drilling conditions to confirm wear behavior and flushing performance.

Quality control focuses on consistency rather than extreme performance. Incoming materials are inspected for composition and cleanliness. During production, critical dimensions such as shank interface and gauge diameter are monitored. Finished bits are checked for button alignment, surface finish, and structural integrity.

This approach ensures predictable performance across large production volumes, which is particularly important for quarry and water well contractors managing operating costs.

Compared to high-pressure DTH bits, medium–low pressure versions offer:

Lower operating stress on drill bits and hammers
More uniform wear over extended drilling periods
Better suitability for continuous production drilling

While penetration rates may be slightly lower, the overall drilling cost per meter is often reduced due to longer bit life and fewer unplanned stops.

TANK DRILLING provides selection guidance based on compressor capacity, formation type, and drilling objectives. Custom face designs, button grades, and shank types are available upon request. With stable manufacturing capacity and export experience, we support timely delivery and responsive technical service.