HDD Used in South Africa
June 29, 2011
Rolkon, recently carried out a major road crossing beneath the N3 toll route highway, opposite PPC cement, Germiston, South Africa, using the latest horizontal directional drilling technique.
Rolkon’s previous experience with no-dig techniques has been with its ever-growing range of Grundomat soil displacement hammers. Due to Rolkon’s continued success, it decided to expand its trenchless capabilities and purchased a Grundodrill 7X plus from the TT Group product supplier Reef Pneumatics, based in Primrose, Germiston near Johannesburg.
The N3 toll route highway bore length crossing was 64 m, a pilot bore was carried out across the highway, which took 2.5 hours to complete. The ground conditions were a mixture of bolder rock and sandy clays, the bolder rock in various parts of the bore was very difficult at times and a great deal of patience was needed to negotiate through difficult areas of the bore. Once the pilot bore was completed a pre-reaming operation was carried out using a 155 back reamer at the same time drill rods were added to the special adapter on the back reamer. These were pulled into the pilot bore which ensured that the borehole was not lost during the pre-reaming operation.
Finally the bundle of PE pipes were installed to the satisfaction of the client Eskom.
This article was submitted by Tracto-Technik.