Extension rods from Crowder Supply connect your rock drill to the bit across every common thread system: R25, R32, R51, T38, T45, T51 and H55. Rods run from 8 in. to 244 in. in male/female or male/male end configurations, on hex and round bar stock from 7/8 in. to 2 in., for extension drilling in mining, tunneling, tiebacks, geotechnical work and construction blast-hole drilling.
Extension strings are built joint by joint shank adapter to rod, rod to coupling adapter, coupling to rock drill bit and every joint wants the same thread system and bar size. Male/male rods pair with couplings; male/female rods stack directly. Crowder Supply stocks rods from Brunner & Lay, Mitsubishi, Rockmore and Sandvik, and the guide to choosing drill steel and rock drill bits covers matching steel to your drill and ground conditions.
- Thread systems: R25, R32, R51, T38, T45, T51 and H55 rope and trapezoidal profiles
- Lengths from 8 in. through 244 in. to build any practical string depth
- End configurations: male/female for direct stacking or male/male for use with couplings
- Bar stock: 7/8 in. hex, 1 in. hex, and 1 in. to 2 in. round sections
- Brands stocked: Brunner & Lay, Mitsubishi, Rockmore and Sandvik
- Applications: extension and production drilling, tiebacks, geotechnical, oil & gas and environmental drilling
- Stocked by Crowder Supply in Denver in the popular sizes
