Products feature
Stop Borehole Collapse. Drill, Grout, and Anchor in a Single Pass.
If you are tunneling or stabilizing slopes in fractured rock, gravel, silt, or fault zones, traditional rock bolting is a contractor's nightmare:
You drill the hole.
You extract the drill steel.
The unsupported borehole collapses before you can insert the bolt.
You waste hours re-drilling or dealing with jammed casings.
Our Self-Drilling Hollow Anchor Bolt (SDA) System solves this permanently. By using the hollow anchor bar as the drill rod, you drill directly with a sacrificial bit, flush through the central bore, and immediately inject grout without pulling out the bar.
Zero borehole collapse risk. 2x to 3x faster installation cycles.
Engineered for Demanding Ground Conditions
Continuous Cold-Rolled Thread Profile:
The fully threaded surface provides superior mechanical interlocking with rock strata and cement grout. Because the thread runs the full length, bars can be cut or coupled at any location using our heavy-duty steel couplers to reach target anchor depths (up to 30m+).
Heavy-Wall Seamless Hollow Tube
Manufactured from high-strength structural alloy steel. It delivers superior torsional resistance during high-torque rotary percussive drilling, preventing rod twisting or premature fatigue snapping.
Optimal Grouting Hydraulic Flow
Large central bore diameter guarantees clean water/air flushing during drilling and smooth, low-pressure slurry flow during final pressure grouting.
Sacrificial Drill Bits for Every Geology
Cross Carbide Bits: For fissured medium-hard rock.
Spherical Button Bits: For abrasive granite and quartzite formations.
Clay & Chisel Bits: For soft soils, weathered marl, and sand layers.
Full System Accessories Available (Factory-Fitted Compatibility)
Never worry about mismatched pitches or loose fittings on the jobsite. We supply the complete load-bearing assembly
Coupling Sleeves: Internal thread stops to ensure equal load transfer between paired anchor bars.
Domed Bearing Plates: High-strength spherical compensation plates designed to accommodate installation angles up to 30 degrees.
Hexagon Domed Nuts: Precision-machined to ensure 100% capacity transfer of the bar's ultimate tensile load.
Thread Protectors: Heavy-duty caps fitted on every thread end to guarantee zero thread damage during container handling and rough underground transport.
Specification
| Parameter (参数) | R25 | R32N / R32S | R38N | R51L / R51N | T76N / T76S |
| Outer Diameter (外径) | 25 mm | 32 mm | 38 mm | 51 mm | 76 mm |
| Inner Diameter (内孔径) | 14 mm | 18.5 mm / 15 mm | 19 mm | 36 mm / 33 mm | 51 mm / 45 mm |
| Yield Load (屈服强度) | ≥ 150 kN | 210 kN / 280 kN | ≥ 400 kN | 450 kN / 630 kN | 1200 kN / 1600 kN |
| Ultimate Tensile Load (抗拉) | ≥ 200 kN | 280 kN / 360 kN | ≥ 500 kN | 550 kN / 800 kN | 1600 kN / 1900 kN |
| Thread Type (螺纹标准) | Left-hand / Right-hand standard rope thread (ISO 10208) | Trapezoidal thread (T) | |||
| Standard Length (标准长度) | 1.0m, 2.0m, 3.0m, 4.0m (Custom cut lengths available) | ||||
| Sacrificial Bits (配套钻头) | Cross bit (Carbide), Button bit, Clay/Arc bit, Chisel bit (Geology-dependent) |
application
Let's Talk Ground Engineering (Get Exact Sizing & Samples)
Not sure whether your project requires R32, R38, or T76?
Don't overspend on over-engineered steel. Send us your project data:
Rock type or RQD level
Required design pull-out load (kN)
Target drilling depth
Our engineering support team will return a complete bill of materials (Anchor bar + Sacrificial bit + Grout volume calculation) within 2 hours.
Our address
Industrial Zone, Linmingguan Town, Yongnian District, Handan, China
Phone Number
easonoflangben@langben.net
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