R Thread Bars – R51
R25 R32 R38 R51 T30 T40 T76

Self-drilling anchor (SDA) combines drilling, insertion and grouting into one easy operation. It reduces project lead time and installation difficulty. Mayland Metallic Materials Ltd. utilizes low carbon steel in all of its anchor production. Low carbon content in steel increases its ductility, reduces its brittleness, and resists corrosion cracking and carbon embrittlement. This choice of material significantly reduces occurrences where rockbolt may snap or buckle during onsite installation.

Anchor Body Drill Bit Hex Nut Arch Plate Coupler

Test Report Link Goes Here

Anchor Body

Rock Bolt Type Outer Diameter Inner Diameter Weight Cross Section Area Yield Load Ultimate Tensile Load
R51XL* 51 mm 38 mm 5.60 kg/m 713 mm2 450 kN 550 kN
R51L 51 mm 36 mm 7.00 kg/m 776 mm2 450 kN 550 kN
R51N 51 mm 33 mm 8.40 kg/m 939 mm2 630 kN 800 kN

*Custom Order Specification

Hex Nut

Hex Nut Type Width Across Flats Length Thread Direction Weight
R51 75 mm 70 mm L 1.60 kg/pc

Drill Bit

EW Clay
Drill Bit Size Drill Bit Type Condition Outer Diameter Weight Thread Direction
R51 EX – Steel Cross Bit Mixed Soils – Soft to Medium Conditions 115 mm 3.80 kg/pc Left
R51 EXX – Carbide Cross Bit Mixed Soils – Soft to Medium Conditions 115 mm 3.80 kg/pc Left
R51 ESSF – Tungsten Carbide Button Bit Medium Soil Condition 90 mm
130 mm
1.90 kg/pc
5.00 kg/pc
R51 EW – Clay Bit Clay and Loose Soil 130 mm 1.85 kg/pc Left


Coupler Type Outer Diameter Length Thread Direction Weight
R51 63 mm 200 mm Left 1.80 kg/pc

Arch Plate

Arch Plate Type Width Length Thickness Hole Diameter Weight
R51L 200 mm 200 mm 30 mm 60 mm 8.70 kg/pc
R51N 250 mm 250 mm 40 mm 60 mm 18.70 kg/pc