The expansion of the green power grid in southern Emsland is entering a significant phase: With the construction of a 12 km long direct current connection from Wietmarschen to Lingen (Ems), Amprion will enable grid connection to BorWin 4 & DolWin 4 by 2028. The egeplast Power Protect PE-RT cable protection pipe system is being used, which was partially installed using the environmentally friendly HDD method.
Amprion Offshore GmbH commissioned ARGE Tief4 BD4 LA Süd, consisting of Knoll GmbH & Co. KG, Bernhard Heckmann GmbH & Co. KG, Depenbrock Bau GmbH & Co. KG and Sonntag Baugesellschaft mbH & Co. KG, to carry out the construction work starting in summer 2024. Amprion chose the cable protection pipe system from egeplast, which has increased thermal stability and is suitable for high and extra-high voltage cables up to 525 kV with various connection technologies (double sleeve, E-sleeve, Golden Seam) and adapters.
Static Calculations as a Service
Due to the nature of the soil, open trenching was used over long distances. However, individual sections could also be installed using the cost-efficient and environmentally friendly HDD method. A particularly complex section involved crossing under the Dortmund-Ems Canal, the Ems river, and a Fauna-Flora-Habitat (FFH) area, a protected area for nature and landscape conservation, in the Lingen Hanekenfähr region. The HDD drilling, with a length of approx. 1,100 m (6 strands), was converted from SDR 11 to SDR 7.4 based on tensile force calculations. A particular challenge here was primarily the pre-laying of the pipes in the difficult-to-access terrain in the forest. Extensive site clearance measures were necessary beforehand for this.
Especially with complex drilling operations like these, good communication and cooperation between the construction company and the pipe manufacturer are necessary in addition to precise planning. Sven Vaske, overall project manager ARGE Tief4 LA Süd, rates the exchange as consistently positive: “egeplast was always at our side during the work preparation with its technical expertise to enable the most effective construction process possible.” These consulting services provided by egeplast included, among other things, the static calculations for the construction and operating state, so that the completion of the southern section is planned for December 2025.
egeplast
egeFit®
Connection Technology “Golden Seam”
Seamless!
The modification of the egeFit® “Golden Seam” connection technology prevents a reduction in tensile strength. The “Golden Seam” is created through a specially developed integrated recess that automatically accommodates the inner bead. Subsequent removal of the weld bead is eliminated. This type of connection is particularly well suited for limited space conditions on the construction site, enabling the connection of longer pipe strings. The “Golden Seam” is available as a fully integrated solution for Power Protect pipe strings. As an adapter, the connector can be flexibly welded to any pipe end.
egeplast
Power Protect PE-RT
Protective pipes for high and extra-high voltage cables with a low-friction inner layer and individual marking.
UV-resistant signal color layer
Solid wall or co-extruded, optionally with stripes
Inspection-friendly inner layer: optionally highly slidable or abrasion-resistant
Project description
BorWin4/DolWin4 South Section; 12 km route length;
Direct current connections from Wietmarschen to Lingen (Ems)
Challenges
Installation of cable protection pipe systems for High-Voltage
Direct Current (HVDC) transmission
Solution
Use of egeplast Power Protect PE-RT cable protection pipe system with
increased thermal stability for high and extra-high voltage cables up to
525 kV with various connection technologies (double sleeve,
E-sleeve, Golden Seam) and adapters
Installation
Open trenching (open-cut installation) & trenchless installation (HDD)
Pipe system
6,900 m egeplast Power Protect PE-RT 280 x 38.3 mm (12 m bars)
7,800 m egeplast Power Protect PE-RT 280 x 25.4 mm (12 m bars)
36,000 m egeplast Power Protect PE-RT 250 x 14.8 mm (15 m bars)
– 200 x PE-RT heating coil welding sleeve d 250 mm
– 1,850 x double sleeves d 250 mm
– 2 x egeFit® connecting piece “Golden Seam” 280 x 25.4 mm
– 40 x adapter d 280 mm (SDR11) to d 250 mm (SDR17)
– other accessories
– Welding equipment (including 2 welding machines)
Project participants
Client: Amprion GmbH
Contractor: ARGE Tief4 BD4 LA Süd (Knoll GmbH & Co. KG, Bernhard Heckmann GmbH & Co. KG, Depenbrock Bau GmbH & Co. KG and Sonntag Baugesellschaft mbH & Co. KG)
