With an increased demand for gas in Poland, two new gas pipelines have been installed in 29 days using the Herrenknecht Direct Pipe technology through challenging geology. As an alternative to open trench construction, the pipeline bore is excavated and the prefabricated pipe is installed as a single operation.
The new lines of 700m and 464m long and 1,047m diameter, are part of the Czeszów to Wierzchowice 14km gas pipeline project and run alongside existing gas lines.
To install the new pipelines, contractor PPI Chrobok selected to use the Herrenknecht Direct Pipe system for the first time in Poland.
The gyrocompass navigation system enabled exact steering of the system’s TBM, which was important as the new pipelines were being installed along existing gas lines. Crews were able to install the two 1,047mm diameter pipelines in 16 and 13 drilling days for the 700m and 464m long drives respectively.
Before this project, horizontal directional drilling (HDD) technology was used for pipeline crossings. The method however is technically and economically limited in heterogeneous, non-stable ground conditions such as the sandy, sticky clay in the Czeszów and Wierzchowice regions of the project. The Direct Pipe method also crossed safely under an ecologically sensitive lake with sufficient power provided by the pipe thruster in the launch shaft to complete the long demanding drive.
“As a combination of HDD and microtunnelling, Direct Pipe overcomes the respective limitations of each," said Roland Kośka, Planning and Monitoring Manager for client GAZ-SYSTEM. “As a result, and to a large extent, there are no longer obstacles to pipeline construction. This will allow us to pursue new projects and complete them quickly, economically and with minimal impact on the local infrastructure and environment.”