German Quarry: Customized T38 High-Strength Drill Rods Solve Breakage Problems in High-Torque Operations, Increasing Pro

1. Customer Background

The customer is a large open-pit quarry in North Rhine-Westphalia, Germany, established in 2005, specializing in basalt and granite mining. Their products supply numerous road and rail infrastructure projects across Europe. In May 2025, the customer contacted us through our website, with the core requirement of customizing T38 drill rods compatible with their heavy-duty rock drilling equipment. Their goal was to solve the problem of frequent breakage and short lifespan of their existing drill rods during high-torque drilling operations, while also ensuring operational safety and compliance.

2. Core Pain Points

The customer previously used T38 drill rods from an East Asian brand. During high-torque drilling operations in basalt (high-hardness rock formation, f=18-22), they faced three major challenges:

• High risk of breakage: Frequent breakage occurred at the drill rod joints, with an average of one drill rod damaged every three days. This not only caused operational interruptions but also posed safety hazards such as flying rock fragments and equipment jamming;
• Short service life: The average service life of a single drill rod was only 300m, requiring the purchase of more than 30 rods per month, significantly increasing operating costs;
• Limited productivity: Frequent drill rod replacements resulted in more than 10 hours of downtime per day. While the planned daily drilling target was 150m, only 90m could actually be completed, failing to meet the tight deadlines of infrastructure projects.

3. Solution

Yanggu Henglong's technical team accurately analyzed the customer's operating conditions (high torque, high impact, and hard rock formations) and, in conjunction with T38 drill pipe technical standards, developed a customized solution of "material upgrade + structural optimization + customized adaptation":

• Material Customization: High-strength 23CrNi3Mo alloy steel was selected as the raw material for the drill pipe body. This material possesses excellent fatigue resistance and impact toughness. After overall heat treatment, the body hardness is stable at HRC 32-38, and the joint is additionally carburized, increasing the hardness to HRC 42-48, enhancing wear resistance and fracture resistance;
• Structural Optimization: The drill pipe joint thread design was optimized, using fine-pitch threads + thickened tooth profile structure to improve thread engagement and reduce stress concentration during high-torque operations; at the same time, the joint length was extended to 120mm to increase the stress contact area and reduce the risk of fracture;
• Compliance Assurance: Third-party authoritative testing was completed to ensure that the product complies with German and EU occupational safety standards;
• Adaptation and After-Sales Service: Based on the customer's heavy-duty rock drilling equipment model, the taper and interface dimensions of the drill pipe are precisely matched to ensure perfect compatibility with the equipment; technical engineers can provide remote guidance on drill pipe installation and torque adjustment, regularly follow up on operating conditions, and promptly answer any questions during use.

4. Implementation Results

• Fracture risk completely eliminated: The customized T38 drill rods showed no fractures or deformation during high-torque operations, and the wear at the joints was controlled within 0.2mm, significantly improving operational safety;
• Service life extended by 167%: The average service life of a single drill rod increased from 300m to 800m, reducing monthly procurement to 10 rods, and decreasing consumable costs from €8000 to €2600, saving €64800 annually;
• Production capacity increased by 35%: The drill rod replacement frequency decreased from one rod every 3 days to one rod every 8 days, reducing daily downtime to less than 3 hours, and increasing the average daily drilling volume from 90m to 121.5m, successfully meeting the construction project schedule requirements;
• Long-term cooperation deepened: In September 2025, the client placed an additional order for 200 customized T38 drill rods, designating Yanggu Henglong as the exclusive supplier of drill rod products and signing a two-year long-term cooperation agreement.

5. Case Summary

This case successfully addressed the client's core pain points of drill rod fracture, short lifespan, and low productivity by accurately understanding the core needs of high-hardness rock formations and high-torque operations, and providing customized material upgrades and structural optimization solutions. This verifies the excellent performance of Yanggu Henglong's customized T38 drill rods under harsh working conditions. Whether you are involved in high-hardness rock mining, heavy-duty rock drilling equipment operations, or have specific specifications and compliance requirements for drill rods, Yanggu Henglong can provide a full-process customized service from material selection and structural design to production and delivery.