The drillings are located parallel to each other with a distance of 3.5 m each and are crossing under the river Isar. To increase the lateral distance the drillings are carried out in different depths of 18.5 and 20.5 m. A minimum distance of 25 m to the main road B20 (which runs directly next to the construction site) has to be guaranteed. Two HDPE pipes DA 250 SDR 7.4 are laid per drilling. The different soil types (gravel, sand, clay) and the proximity to the river Isar have been very challenging for the employees on site. Also the season with temperatures under zero degrees is complicated, because the wetted lines as well as the recycling plants and pumps freeze quickly. However, the downtime within the drilling process is kept as low as possible and the construction site is operated within 24-h-shifts.
Despite these demanding conditions the powerful, fully electric driven horizontal drilling rig HDD45-E can successfully play off its advantages like e.g. reduced CO2 and noise emissions. Moreover, the fully electric driven mud pump HPP400-E is on duty. Due to their fully electric drive both machines in combination contribute to a holistic future-focused and sustainable site concept. Both the HDD45-E and the HPP400-E were developed by STREICHER itself and are used in practice here for the first time.
These activities are part of an extensive energy project. In this region Bayernwerk replaces severel kilometers of overhead power lines by underground lines and provides a higher network capacity.