Where Pipe Jacking is a man-entry activity, Auger Boring is done by machine and can therefore be much smaller diameters. We are currently capable of installing a 600mm diameter steel sleeve or a 450mm concrete sleeve. Auger Boring is a much faster method but is limited to about 70m lengths and subject to the hardness of the rock encountered. As with Pipe Jacking it is also an essential pre-requisite for any potential auger bore to complete a thorough study of the prevailing geology to be made available to all interested parties at an early stage. This is the only way of ensuring a cost-effective solution to any given problem.
The Auger Boring Technique
Auger Boring is a technique for installing underground pipelines, ducts and culverts without the use of open trenches. A hydraulic drive train is used to push a steel sleeve through the ground, cutting and drilling into the ground. The soil is discarded through the sleeve pipe by steel flights from where it is spoiled on the side of the excavation. On completion the steel sleeve is usually pushed out and replaced by a concrete sleeve of the same outside diameter. Bentonite is pumped into the space between the sleeve and the ground during installation to assist with friction as well as filling any voids caused by the operation. The technique ensures a structural sound and watertight finished pipeline. The length of individual sleeves is restricted by the length of the available flights, with a maximum of about 120 meter.