To improve grid stability in its own gas network, the grid operator SWS Netze GmbH in Stralsund is investing in a new high-pressure connecting pipeline. This connects the Stralsund West and East transfer stations and aims to ensure a more balanced utilization between both stations in the future. The contracted construction company Beermann is relying on egeplast HexelOne® SLM pipes for the approximately 6 km long high-pressure connecting pipeline, which will be largely installed trenchlessly using the HDD method.
Plastic Replaces Steel Pipes
Construction already began in 2022 (1st section). The construction company started the 2nd section on September 6, 2023, and the challenging project is expected to be completed in Q4/2023. The planning and implementation of the construction measure were particularly complex because the client had no prior experience with plastic pipe systems, as steel was always used in this segment before. egeplast is the only manufacturer to offer a DVGW-certified high-pressure polyethylene gas pipe system.
A challenge worth mentioning is that all work can only take place after the harvesting of agricultural areas. The connections in the intermediate construction pits were also complex, as the loose pipe ends faced each other. In this case, the connection was easily made using press connectors from the egeplast HexelOne® system and the corresponding special hydraulic pressing tool.
The construction company installs the pipes almost entirely using the trenchless HDD horizontal drilling method, which enables them to ensure rapid installation. The environmentally friendly and economical aspect is also not neglected here, as rapid progress is achieved with, on the one hand, large coiled pipe delivery lengths and thus relatively few pipe connections. At the same time, the contractor, Beermann Bohrtechnik, achieves maximum pipe pull-in lengths through the use of state-of-the-art technology and extensive know-how.
Smooth Project Execution
The desired equalization of problematic deviations regarding the capacity utilization of the existing transfer stations has been achieved. Another major advantage: Major conversion and maintenance work at the transfer stations can now be planned by the network operator without supply interruptions, thanks to the new interconnector. “The newly created high-pressure interconnector allows us to utilize our gas network significantly more effectively and fully fulfills its intended purpose,” states Olaf Lemke, responsible Project Manager at SWS Netze GmbH.
egeplast
HexelOne® SLM
The egeplast HexelOne® SLM pipe is a self-reinforced high-pressure pipe, a monocomposite made solely from polyethylene.
This reinforcement enables new areas of application in the “raised pressure” range, i.e., operating pressures above the applications previously covered by PE pipes.
The reason: It exhibits twice the strength compared to previous PE pipes.
Learn moreProject description
Construction of a new high-pressure gas supply pipeline to connect two transfer stations
Challenges
All work can only be carried out after agricultural areas have been harvested; connection of pipe strings in the intermediate excavation pits
Solution
Press connectors (HexelPress®), large delivery lengths in coils, thus minimizing connection work
Installation
Horizontal Directional Drilling (HDD)
Pipe system
HexelOne® SLM DA 160 (approx. 6,000 m, practical delivery form as coils); connection of the coils using “combination welding” compliant with DVS 2207; connection of the individual pipe strings pulled in by HDD method using HexelPress® connectors (V4A stainless steel)
Project participants
Client: SWS Energie GmbH, Stralsund
Commissioned Contractor: Beermann, Demmin Branch, Mecklenburg-Vorpommern
Involved Civil Engineering Specialist Dealer: Gebr. Hansen, Velgast, Mecklenburg-Vorpommern
Supervised by TÜV Nord
