Product Description
RockHound T38-H32-R32 Drifter Rods are purpose-engineered for high-frequency, high-impact underground drifting and development drilling. Manufactured from ZK22CrNi3Mo (Cr-Ni-Mo alloy steel), the rods deliver an optimal balance of core toughness and surface hardness through a full carburization + quench-temper heat treatment process.
The H32 (32mm / 1 1/4″ A/F hexagonal) cross-section provides superior rotational rigidity and facilitates fast, reliable uncoupling in production cycles. The male T38 thread (shank end) and female R32 thread (bit end) are CNC precision-machined to guarantee zero-tolerance fit with standard T38 shank adapters and R32 drill bits, minimizing energy reflection loss during percussion.
The optimized internal flushing channel ensures consistent debris evacuation and bit cooling, directly extending consumable service life in hard and abrasive rock formations.
Key Features
- ZK22CrNi3Mo Alloy Steel: High Cr-Ni-Mo specification provides exceptional impact fatigue strength — the critical property for drifter rod longevity under hydraulic top-hammer loads
- Full Carburization Heat Treatment: Hardened case depth ensures resistance to thread galling, surface pitting, and bending fatigue
- Precision CNC T38 & R32 Threading: Machined to ISO/SIS thread standards; ensures full shoulder contact and efficient percussive energy transfer
- H32 Hexagonal Body (32mm / 1 1/4″ A/F): Hex profile prevents rotation slippage in the feed chuck and simplifies rod handling and uncoupling
- Optimized Flushing Bore: Smooth, consistently-sized internal hole maintains high flushing velocity for effective cuttings removal
- Compatible with Major OEM Drills: Atlas Copco (Epiroc), Sandvik, Furukawa, Montabert and equivalent hydraulic drifters
Specifications
| Drifter Rod Type | L (mm) | L (foot / inch) | H (mm) | H (inch) | Product Code | Weight (kg) |
|---|---|---|---|---|---|---|
| R38-H32-R32 – Male R38 / Female R32 × Male R32 | ||||||
| R38-H32-R32 | 3700 | 12′ 1 1/2″ | 32 | 1 1/4″ | 276-3237-5654 | 23.6 |
| 4305 | 14′ 1 31/64″ | 276-3243-5654 | 27.5 | |||
| 4915 | 16′ 1 1/2″ | 276-3249-5654 | 31.4 | |||
| T38-H32-R32 – Male T38 / Female R32 × Male R32 | ||||||
| T38-H32-R32 | 3700 | 12′ 1 1/2″ | 32 | 1 1/4″ | 276-3237-7654 | 23.6 |
| 4305 | 14′ 1 31/64″ | 276-3243-7654 | 27.5 | |||
Applications
The T38-H32-R32 Drifter Rod is the preferred choice for:
- Underground Hard Rock Mining: Development drifting, cross-cutting, and ore production drilling
- Tunnel Construction: High-speed face drilling with drill jumbos (single or twin-boom)
- Civil Engineering & Infrastructure: Shaft sinking, raise drilling, and rock bolt hole drilling
- Quarrying: Bench drilling and secondary breaking where R32 bit compatibility is required
Rock Hardness Range: Best suited for medium to extremely hard rock (UCS 80–300 MPa), where ZK22CrNi3Mo impact fatigue strength is critical.
Maintenance Guidelines
- Thread Lubrication: Apply approved thread grease (anti-seize compound) to T38 and R32 threads before every connection to prevent galling and seizing
- Full Shoulder Make-Up: Ensure threads are tightened to full shoulder contact — partial engagement is the primary cause of thread fatigue fracture
- Pre-Shift Inspection: Check all thread profiles for chipping, flaking, or deformation; inspect the rod body for transverse cracks or excessive bending (straightness tolerance: ≤1mm/m)
- Rotation Protocol: Observe correct drill rotation direction and avoid reverse rotation under percussion load, which accelerates thread wear
- Storage: Store horizontally on rod racks, away from moisture; apply rust-preventive oil for storage periods exceeding 30 days
How to Select the Right Drifter Rod
| Selection Factor | Guidance |
|---|---|
| Shank Adapter Thread | Must match T38 — verify your jumbo drill’s adapter specification before ordering to ensure perfect compatibility and energy transfer. |
| Drill Bit Thread | This rod accepts R32 button bits or cross bits on the bit end — ideal for most drifting and tunneling applications. |
| Feed Length | Select 3700mm for shorter feeds / tighter headings; choose 4305mm for standard development jumbos and deeper rounds. |
| Rock Type | ZK22CrNi3Mo is recommended for abrasive and hard rock formations (UCS > 150 MPa); standard Cr-Mo grades suit softer or less abrasive conditions. |
| Body Profile | H32 hex is the industry standard for drifting — provides superior chuck grip, reduced slippage, and better torque transmission compared to round (R32) body rods. |
Related Products
- R32 Coupling Sleeve
FAQ
These rods are manufactured from ZK22CrNi3Mo, a high-specification Chromium-Nickel-Molybdenum alloy steel. This material grade is specifically selected for drifter rod applications because:
- Cr (Chromium) improves surface hardness and corrosion resistance
- Ni (Nickel) enhances core toughness and resistance to impact fracture
- Mo (Molybdenum) increases fatigue strength under repeated high-frequency percussion loads
Combined with a full carburization + quench-temper heat treatment, the result is a rod with a hard, wear-resistant surface and a tough, crack-resistant core — the ideal combination for hydraulic top-hammer drilling in hard rock.
Standard stocked lengths for the T38-H32-R32 are:
| Length | Product Code | Best For |
|---|---|---|
| 3700mm (12' 1 1/2") | 276-3237-7654 | Shorter feed beams, confined headings |
| 4305mm (14' 1 31/64") | 276-3243-7654 | Standard development jumbos |
| Custom (e.g. 4915mm) | On request | Special feed length requirements |
Selection tip: Match the rod length to your drill jumbo's feed beam stroke. The rod should be 100–150mm shorter than the maximum feed travel to allow proper make-up at both thread ends.
The 4915mm length is a standard stocked size for the R38-H32-R32 variant (Product Code: 276-3249-5654), not the T38-H32-R32. For T38-H32-R32 at 4915mm or other non-standard lengths, custom orders are accepted. Please contact us with your required length, quantity, and drilling application details for a lead time and pricing quote.
The T38-H32-R32 Drifter Rod is compatible with all major hydraulic top-hammer drill jumbos that use a T38 shank adapter, including but not limited to:
- Epiroc (Atlas Copco): Boomer series (E1, E2, M2, XE3, 282)
- Sandvik: DD series (DD210, DD310, DD420, DD422i)
- Furukawa / FRD: HCR series
- Montabert: HC series
Always verify your specific machine's shank adapter thread specification before ordering. If your shank adapter is R38 (rather than T38), you will need the R38-H32-R32 variant instead.
Both T38 and R38 are 38mm nominal diameter threads, but they differ in thread profile geometry:
- T38 — Trapezoidal thread form; offers high fatigue resistance and is the more widely adopted standard on modern hydraulic jumbos
- R38 — Rope (semi-round) thread form; an older standard still common on certain drill models and markets
The two thread types are not interchangeable. Always match your drifter rod shank thread to your machine's shank adapter. If unsure, check your shank adapter's part number or measure the thread pitch and profile.
The H32 hexagonal body offers several practical advantages over round-body rods in drifting applications:
- Chuck Grip: The hex profile engages positively in the drill's rotation chuck, preventing rod slip under high torque
- Uncoupling: Flat faces allow a wrench to be applied directly to the rod body for easier mechanical uncoupling, especially when joints have seized
- Structural Rigidity: The hex section has a higher second moment of area than a round section of the same weight, offering better bending stiffness in long hole applications
Yes — thread lubrication is non-negotiable. Dry coupling under percussion leads to fretting, galling, and premature thread failure, which is the single most common and avoidable cause of drifter rod rejection.
Use an approved anti-seize thread grease specifically formulated for percussive drill steels (e.g., Atlas Copco Rock Drill Oil, Sandvik Thread Grease, or equivalent EP (Extreme Pressure) anti-seize compound). Apply a light, even coating to all male threads before every connection. Do not apply grease to the flushing hole or rod bore.
Retire a rod immediately if any of the following are observed:
- Thread damage: Chipped, flattened, or cracked thread crests that prevent full shoulder make-up
- Transverse cracks: Any crack perpendicular to the rod axis is a precursor to catastrophic fatigue fracture
- Excessive bending: Visible curvature or runout exceeding 1mm per meter of rod length
- Shoulder face erosion: Significant washing or erosion of the thread shoulder face, indicating improper make-up or flushing leakage
- Surface pitting or corrosion: Deep pitting acts as a stress concentration point and will initiate fatigue cracks under percussion
Continuing to use damaged rods risks drill damage, stuck steel, and safety incidents underground.
Yes. The R32 female thread on the bit end of this rod accepts any standard R32-threaded bit, including:
- R32 spherical (dome) button bits
- R32 flat face button bits
- R32 drop center button bits
- R32 cross bits (chisel bits)
Bit selection should be based on rock type and formation structure, not the rod. Contact our technical team if you need bit selection guidance for your specific geology.
Yes. We supply drifter rods to OEM specifications and private-label branding for distributors and drill tool integrators worldwide. Custom options include non-standard lengths, alternative thread combinations, special heat treatment specifications, and branded packaging. Minimum order quantities apply — please inquire directly for OEM terms.