Definition - What does Conductor Barrel mean?
A conductor barrel is the outermost casing string that is first put into the borehole. Pipe ramming is used to install conductor barrels in directional drilling operations where unknown soil conditions pose a risk of borehole collapse.
In unconsolidated shallow formations, the conductor barrel is set immediately after drilling has commenced preventing the formations from caving in or washing out.
Trenchlesspedia explains Conductor Barrel
In unknown soil conditions where soil easily slips and where dewatering is not practical, pipe ramming can be used to install conductor barrels. This is especially useful under embankments and highways to conduct uninterrupted operations while keeping the surface undisturbed. The conductor pipe holds back the unconsolidated formations and prevents surrounding soil from falling into the borehole.
The conductor barrel acts as support casing for equipment as well as for product pipe. In some cases where there is loose surface soil, the conductor pipe is first driven into the soil after which drilling is commenced.