Overburden Drilling Pipes & Acc.

    Also shortened to OD Drilling, overburden drilling is designed to handle tricky drilling and its performance is not impaired by any changes in the formation ranging from loose soil stratum to homogenous rock. The method cuts straight through stones and boulders or shoulders them aside.  The variety encounted in overburden formations, often unstable, makes overburden drilling one of the most difficult types of drilling there is.

Typical situations where OD Drilling is at its best:

• Drilling holes in civil engineering projects:
  • anchoring
  • grouting
  • pipe and cable - laying through highways and railway embankments
  • drilling blast holes without soil removal
• Mineral Prospecting:
  • pilot holes for diamond drilling
  • sampling cuttings
  • sampling soil
  • overburden thickness studies
  • water table studies
• Drilling water wells
   
  • casing from surface down to rock bed
  • casing all through unstable formations
  • exclusion of upper water layers, which are frequently polluted

How It Works

    The bit drills the bottom of the hole.  As rotation commences, the bit widens the hole and cuts a passage for the smooth descent of the casing.  Cuttings are flushed upwards inside the casing tubes.
    On completion of the drilling, the equipment is put into reverse and passes upward though the casing tubes.
    Standard drilling equipment such as rock bits are used for continued drilling through the casing tubes once the solid bed rock has been reached.
    Casing tubes can be left in position to stabilize the hole or withdrawn after the installation of cables, plastic tubes, or other equipment.