Trenchless pipe rehabilitation of gravity piping systems
Close-fit reduction process (Swagelining/DynTec method)
The reduction process was originally developed for the rehabilitation of pressure pipelines in the wastewater, drinking water and gas sectors.
PE 100 pressure pipes SDR 17 (PN 10) and SDR 11 (PN 16) are primarily used in this process. Structurally self-supporting liner pipes SDR 21 (SN 8), SDR 26 (SN 4) and SDR 33 (SN 2) are used for liner pipes in the field of gravity piping systems.
As part of the reduction process, a PE pipe run is drawn through a die that elastically deforms the PE liner pipe under a continuous axial tensile load and briefly reduces the cross section by up to 10%. The pipe run with its reduced cross section is then drawn into the old pipe. After insertion and the elimination of tensile stress, the PE pipe returns to its original outside diameter and clings to the inside wall of the old pipe to create a "close fit".
The outcome of the rehabilitation procedure is a new, independently load-bearing liner pipe that merely reduces the original hydraulic capacity of the pipeline by the wall thickness of the PE liner.
As a system manufacturer, SIMONA offers not only pipes and electrofusion sockets but also application-specific fittings depending on the special dimensional requirements – tailored to the requirements of the reduction process.
Rehabilitation range
DN 100 – DN 1200
SDR 11 – SDR 26
Reference
Rehabilitation of gas and water pipelines by PE relining without annular space
DVGW Worksheet GW 320-2