Horizontal directional drilling is a process that is split into four stages, which includes:

Horizontally drilling a pilot hole under and across the obstacle

Enlarging the borehole by pre-reaming the horizontal boring to larger diameters

Conducting pull back operations by attaching the reamer to the drill string and connecting it to a pulling head


Installing the conduit by pulling the product into a position within the confines of a pipe.

There are multiple functions that are served by drilling fluids, including, but not limited to:

  • Remove Cuttings from bore hole.
  • Formation pressure control
  • Stabilise bore hole from collapse
  • Lubricate and protecting Bits and Tooling
  • Clear cuttings away from cutting face
  • Keep Tooling and Transmitter cool and from overheating
  • Maximise tooling life

Drilling muds are also known as drilling fluids. They must be used in HDD by first being mixed in your Mixing System and Tanks then pumped down your drill string.


They are a complex part to drilling but integral to ensuring you get your job done fast and efficiently.


Never underestimate the power of a correct Mud Mix and Mud Flow when drilling on Pilot or Reaming.

Horizontal directional drilling technique for dirt/clay

  • Bore the pilot hole using a Blade.
  • Pull back using a Paddle reamer and Swivel to pull the pipe or cable through.

Horizontal directional drilling techniques drilling in soft rock

Horizontal directional drilling techniques for hard rock

  • Bore the pilot hole with either a Rock Motor and Tricone or PDC bit or an Air-Hammer. Steer via positioning the bent sub.
  • a.Pull back using a Hole Opener and Swivel. The use of this tool makes the hole larger and allows a larger pipe or cable to be pulled through the cavity.

There are three primary benefits of directional drilling:

Installing any infrastructural material is a lot easier with directional drilling as it requires only a single pilot hole

Directional drilling is highly cost effective as it is virtually trenchless and does not require a significant amount of equipment to dig a trench for replacing underground piping

There is very little disruption that comes into landscaping when it comes to directional