Auger Drilling Techniques | Percussion Drilling Techniques | OdexTM or TUBEX | Grout Pumps | Grout Sources
Vibratory Drilling Techniques (Crane & Mandrel) | Air Rotary or Rotary Wash | Grout Mixes | Slump Test

The second percussion method uses an inner drill string that is simultaneously advanced with an outer casing. The drill bit is set slightly ahead of the end of the drill casing. One system of this method used for difficult drilling conditions is the OdexTM system. The OdexTM system utilizes an eccentric under reamer to cut a drilled hole ahead of the bottom of the casing. The casing is then simultaneously advanced by a percussive force applied to either the top or bottom of the casing. As the hole is advanced, the drill cuttings are normally removed by air and travel up the inside of the casing in the annular space between the casing ID and the drill rod OD. The OdexTM method is highly effective in overburden soils where boulders or gravel layers are present, or when layers of rock must be penetrated. This method also subjects surficial and localized soils to some vibration.

Figure 5.  Crane & Mandrel Crane Drill