Extension rods are made by hollow drill steels. This hollow hole are usually named flushing hole, used for transmitting water or air during drilling.
And the threads can be used for connecting couplings, shanks, couplings or bits.
There are two shapes of extension rods, round type and hexagonal type.
Hexagon rods are more rigid, heavier and transfer energy more efficiently, while increasing flushing.
Round rods are generally lighter than hexagonal rods and are normally used in extension drilling applications.
Extension Rod(MM Rod)
Thread Sizes: R22, R25, R28, R32, R35, R38, T38, T45, T51
Rod Diameters: Round 32mm, Round 39mm, Round 46mm, Round 52mm, Hex 22mm, Hex 25mm, Hex 28mm, Hex 32mm, Hex 35mm
Effective Lengths: 600mm to 6,400mm
Male/Female (M/F) rod, Speed rod
Thread Sizes: R32, T38, T45, T51
Rod Diameters: Round 32mm, Round 39mm, Round 46mm, Round 52mm
Effective Lengths: 915mm to 6,100mm
Drifting & Tunneling Rods
Thread Sizes: R22, R25, R28, R32, R38, T38
Rod Diameters: Round 32mm, Round 39mm, Hex 25mm, Hex 28mm, Hex 32mm, Hex 35mm
Effective Lengths: 2,100mm to 6,400mm