drill bit extension rod with two R38 external threads

Features of the drill bit extension rod

• The rod has a round cross-section with a diameter of 39 mm. Compared to extension rods with a hexagonal cross-section, it uses less material, is lighter in weight, and is more economical.
• Both ends are R38 external threads, which means R38 external thread.

Various manufacturing processes for the drill bit extension rod

Carburizing Process

For large diameter drill rods, carburizing is mainly used. This process hardens the entire drill rod and forms a uniform carbon layer on the outer surface, significantly improving the rod’s strength and wear resistance. Carburized drill rods are mainly used for underground operations and where water is used as the flushing medium.

High-Frequency Hardening Process

For small diameter drill rods, high-frequency hardening is mainly used. This process hardens only the threaded ends of the rod, effectively reducing the brittleness of the rod body. This technique not only extends product service life but also makes the rod suitable for various drilling conditions. Drill rods produced by this process are mainly used for surface drilling operations where air is the primary flushing medium.

Phosphating Process

Phosphating is commonly used to improve the corrosion resistance of the drill rod’s outer surface, thereby enhancing its service life and stability in harsh environments.

Technical specifications

• Length: 1220 mm, 1525 mm, and 1830 mm are available.
• Specification: R38-round 39-R38
• Weight: Ranges from 10.0 kg to 14.9 kg, with specific information provided in the table.
• Material: High-strength alloy structural steel, 23CrNi3Mo
• Manufacturing process: Fully carburized