The Horizontal Directional Drilling method enables to lay a prefabricated pipeline into the ground by the creation of a borehole in which the pipeline is pulled in. The method is used for decades. Nowadays a trend to the installation of longer pipelines and larger diameters is clearly visible. Pipelines are installed faster by the reduction of the number of reaming stages during which the borehole is reamed. This faster installation process of the longer pipelines in larger boreholes is only possible by improvement of the flow of drilling fluid. The improved flow of drilling fluid is necessary for a lower pressure gradient in between the drilling head and the entry point and also for the transport of the cut soil particles out of the borehole.

dr Henk M.G. Kruse, Deltares

Senior geotechnical consult and is working in the field of underground infrastructure. He is a specialist in geo engineering of pipelines especially in the disciplines of trench less installation techniques and the effects of installation activities on the surroundings.