Horizontal directional drilling (HDD) machines are steerable, trenchless drilling rigs for the installation of pipes, conduits, and cables underground in a shallow arc. They are commonly used for installations below waterways and roadways to avoid disturbing the ground above.
Horizontal drilling machines are typically heavy-duty vehicles fitted with track drives, operator controls, and drilling machinery. Materials used for pipes include PVC, polyethylene, polypropylene, ductile iron, and steel.
