Definition - What does Drill Rod mean?
Drill rods are segments of stainless steel piping, which are joined together to form a drill string. The drill string connects the drilling rig at the surface to the drilling head at the tunnel face.
It is used to provide rotational torque to the drilling head, as well as to supply drilling fluid from the surface to the cutting face.
Trenchlesspedia explains Drill Rod
Drill rods are manufactured from high-quality stainless steel or other specialized materials due to the extreme working conditions they are exposed to. Because drill rods carry the driving force of the drill rig to the drilling head, they must be extremely strong, and because they travel long distances in underground tunnels, they must be flexible too.
Drill rods are joined together by threaded connections which are also subject to significant working stresses.
Choosing high-quality drill rods and maintaining them carefully is a critical part of a horizontal directional drilling (HDD) project because a failure in the drill string can be very costly in terms of time lost, while the drill string is removed, repaired and then reinstalled.