Odex and Symmetrix Drilling

Odex drilling and or Symmetrix drilling is often used in situations where the ground formation is relatively soft or less consolidated, such as in loose soils, clay, and sand or boulders. It is also commonly used in areas where there is a risk of collapsing boreholes or unstable formations.

Odex and Symmetrix drilling methods both include using a specialised drilling bit that connects and disengages a casing shoe that is welded to the steel casing string and drilled into the ground pulling the casing with the drilling bit. After the desired depth is reached the drill bit disengages from the casing shoe and the drilling string is removed and drilling can continue with a smaller size drilling bit.

In-situ perforation, in some cases, refers to the process of creating openings or perforations in the casing of a borehole after it is installed. This allows water to flow at a desired position in the borehole and the extraction thereof.

However, Odex or Symmetric drilling does have some limitations. It is not as effective in hard rock formations, where other drilling techniques like diamond drilling or rotary drilling may be more suitable.