© adobestock.com/Sina Ettmer
Lesedauer: Berechne...
Follow a manual added link
egeplast
egeplast
Contacts
Dr.-Ing. Thorsten Späth
+49 2575 9710 000
Dipl. Ing. Nils Best
+49 172 5879 279
The rehabilitation of a water main in Hötensleben presented major challenges for the local water utility and sewage treatment plant operator, TAV Börde. In view of the challenging route as well as confined access routes, the egeplast egeLiner®, together with close-fit lining was used, representing an efficient and environmentally friendly solution.
Ecologically compatible method
Even while performing the preliminary works required for the rehabilitation project in Hötensleben close to the former inner-German border, the contractor, Esders Pipeline Service GmbH, had to master special challenges in September 2022. For example, a package of filter gravel had become loosened from a pump system and resulted in increased deposits in the old pipe which had to be removed with the help of ultra high pressure cleaning.
The preexisting bends, reducers and various materials used for the old pipes, such as cast iron, steel, PVC and asbestos cement pipelines hampered the rehabilitation measure. Moreover, the pipe route created additional challenges since it largely led across agricultural land as well as occasionally through residential areas. Last but not least, narrow access routes and spatially very confined traffic zones in some segments of the route to be rehabilitated complicated the implementation of the project.
In selecting the rehabilitation method, the method of choice therefore was the soilconserving and ecologically compatible PErelining without annular gap (close-fit lining) in accordance with the DVGW work sheet GW 320-2. This deformation method limits trenchdigging to just a few sites, this way conserving resources such as fertile soils (e.g. the humous topsoil) and avoiding unnecessary burdens to the surrounding natural environment.
Effort and costs significantly reduced
Following exposure and removal of the relevant pipeline segments in the trenches, the existing drinking water pressure pipe was checked for any potential obstacles, deposits, contaminations or damages to the pipeline. The subsequent ultra-high pressure cleaning was followed by a calibration of the old pipeline in preparation of pulling in the new pipe, the egeLiner®, via the starting pit.
The starting and target pits as well as the exposure of the existing old pipeline were carried out by SPIE Versorgungstechnik GmbH Gommern, on behalf of TAV Börde. The pulling equipment, which usually consists in a capstan winch, pulling the folded egeLiner® from the drum via the starting pit into the host pipeline and to the end pit. This procedure demonstrates one of the huge benefits of the deformation method compared to the classical method involving the pipe string with an annular gap. After all, since the minimum bending radius of close-fit liners is significantly smaller than the bending radius involved in a regular relining with annular gap, the dimensions of the construction pits can be reduced. Consequently, this measure will also help to reduce the excavation effort and thus also significantly reduce the expenses involved as well as any other forms of impairment, also because it does not require any pipe laying and pre-welding to section length of the pipe string above ground. Instead, the required project-specific lengths are manufactured at the plant and delivered on drums.
Final operations
The successful installation was followed by two steps: a pressure test as well as disinfection or a bacteriological examination respectively. Thereafter the rehabilitated pipeline was put into operation.
The connection to the pre-existing old pipeline on the construction site in Hötensleben was carried out with commercial PE pipe OD160 SDR17 PN10 with the aid of relining electrofusion couplers DN150/160 and previously inserted support sleeves made of stainless steel, since the outer diameter of the egeLiner® is slightly smaller than the outer diameter of the standard pipe.
All in all, Firma Esders Pipeline Service ended up rehabilitating approx. 650 m of dilapidated drinking water pipes in Hötensleben.
egeplast
egeLiner®
| The pre-deformed egeLiner® is wound onto steel drums – matched to the required length of pipe to be rehabilitated. This way, the cross section can be reduced by up to 40 percent, meaning that large overall lengths can be supplied to the construction site. |
| As a matter of principle, the folded egeLiner® pipe attempts to balance the tensions which have been frozen in the pipe wall and to transform the pipe in a way which causes it to once again take on its rounded original shape, referred to as a reversion process which enables it to return to its original shape (“memory effect”). This is the property which makes the close-fit method so efficient and ensures that the egeLiner® fits tightly to the inner wall of the old pipe following successful installation and can be integrated fully into the existing pipe network. |
| Project description | Rehabilitation of a 650 m long water main DN150 |
| Challenges | Limited navigability of the route, confined space conditions, pipe bends, strong incrustations and deposits, hydraulic capacity |
| Solution | Trenchless rehabilitation by means of close-fit lining |
| Installation | Deformation process |
| Pipe system | egeLiner® DN150 SDR17 made of PE 100-RC |
| Parties involved in the project | Client: TAV Trink- und Abwasserverband Börde Planning, Installation: Esders Pipeline Service |
Dr.-Ing. Thorsten Späth
Head of Productmanagement, egeplast international GmbH
E-Mail: Thorsten.Spaeth@egeplast.de
Tel.: +49 2575 9710 266
Dipl. Ing. Nils Best
Regional Manager North & East, Esders Pipeline Service GmbH
E-Mail: nils.best@pipeline.esders.de
Tel. +49 172 5879 279
