Faster Installation with Smart Connect

Plug – weld – seal: Faster Installation with Smart Connect

With the Smart Connect system, egeplast has developed a connection technology that meets both the requirements of the respective installation technique and the technical specifications for underground cable construction. To meet all requirements for cable protection pipe systems for underground cable construction in the extra-high voltage range up to 525 kV, not only the choice of the right pipe and the associated raw material is of great importance. A pipe connection tailored to the respective installation technique is also crucial.

In underground cable projects in recent years, many customers expressed the desire for a connection system that meets the requirements of every installation technique. egeplast then developed Smart Connect. Previously, in this segment, push-fit socket systems were used for open trench installation on straight sections. In curved sections, either electro-fusion couplers were used, or the pipes were connected using the butt fusion welding method.

Practical experience:

1. Plow installation

During plowing, mainly bending loads act on the pipe and connection technology. Especially for alternative installation methods, a meandering arrangement of the welding wire was developed for the Smart Connect connection to increase strength. This connection technology was successfully tested in practice in several plowing tests at the Frank Föckersperger test site in Aurachtal.

Frank Föckersperger, (Managing Director) on this: “As part of our research project, we were able to develop a multi-plow for plowing in extra-high voltage lines. Its plow shafts treat the pipe strings very gently during the pulling-in phase and thus maintain the quality of the pipe connections. Smart Connect has proven itself in practice for plow installation due to the fast production of pipe strings without protruding sockets and without internal or external beads. The results of various tests on pulled-in Smart Connect connections confirm this.”

2. Installation with trench box method

On the Wahle-Mecklar route in Westerlinde, the Smart Connect connection in pipe dimension d 250 mm SDR 17 was successfully installed in a construction section using the trench box method. An excavator creates the pipe trench to the width of the box and pulls the box behind it in stages. Three cable protection pipe strings are guided past the excavator and led into the box via deflection rollers. In this installation method, too, mainly bending loads occur.

Mr. Stefan Kürzinger, Foreman Max Bögl, on this: “When welding prefabricated pipe strings using the butt fusion welding method, subsequent removal of the internal bead is not possible. In the area of a road crossing, Smart Connect system welded connections with smooth transitions both inside the pipe and on the outer wall of the pipes could be produced. This ensures smooth pulling-in of the pipes into the trench box, as well as the subsequent pulling-in of the power cables without obstacles. Furthermore, it is always possible to easily repair damaged areas in prefabricated strings using manufactured meter sections in the Smart Connect system.”

3. Installation using the horizontal directional drilling method

On the Ganderkesee route, the Smart Connect connection in pipe dimension d 280 SDR 17 was used in the HDD method. In this method, mainly tensile loads and some bending loads act on the pipe connection. Together with the construction companies Bohlen & Doyen, Matthäi, and Beermann, twelve pipes (a total of 432 m) were successfully installed as a road crossing using the HDD method on a 36 m section. To assess the welded connection, Smart Connect connections were attached to the front end of two strings, which were removed after pipe pulling and subjected to extensive QA testing. Smart Connect also met all requirements for this type of installation.

Philipp Oliv, Project Manager for Land Cable Construction and Drilling Technology, on this: “Under certain conditions, pipe connections via Smart Connect can significantly shorten the time for producing pipe strings for the HDD method compared to the butt fusion welding method. This leads to a noticeable reduction in construction time and holds great potential.”

4. Open trench installation

For open trench installation on straight sections without changes in direction, modified double sockets with a large insertion depth are preferably used. In curved sections, welding of the pipes is required. In the Legden-Asbeck project, Smart Connect in pipe dimension d 250 mm SDR 17 was used in the area of a road crossing. Niklas Nelsen, Construction Manager for Pipe Construction ARGE Schutzrohranlage Legden Asbeck, says: “When using Smart Connect, the connection of the pipes can be carried out significantly faster compared to welding with electro-fusion couplers, as machining of the surface is not required. This can significantly shorten the overall construction time.”